package for alternative energy sources-250803

Indonesia Australia Partnership for Skills Development

Batam Institutional Development Project

Paket Pembelajaran dan Penilaian

Kode Unit : XXXX

ALTERNATIVE ENERGY SOURCES

(August 2003 )

Daftar IsiBAB 1 PENGANTAR..........................................................................................................1

Selamat Berjumpa di Buku Pedoman ini !...................................................................1

Persyaratan Minimal Kemampuan Membaca, Menulis & Berhitung............................1

Definisi.........................................................................................................................1

Berapa Lama Mencapai Kompetensi ?........................................................................2

Simbol..........................................................................................................................2

Terminologi..................................................................................................................2

BAB 2 ARAHAN BAGI PELATIH.......................................................................................5

Peran Pelatih................................................................................................................5

Strategi Penyajian........................................................................................................5

Alat Bantu yang Dibutuhkan untuk Menyajikan Kompetensi Ini...................................5

Peraturan.....................................................................................................................6

Sumber-sumber untuk Mendapatkan Informasi Tambahan.........................................6

BAB 3 STANDAR KOMPETENSI.......................................................................................7

Judul Unit.....................................................................................................................7

Deskripsi Unit...............................................................................................................7

Kemampuan Awal........................................................................................................7

Elemen Kompetensi dan Kriteria Unjuk Kerja..............................................................7

Variabel........................................................................................................................8

Pengetahuan dan Keterampilan Pokok.......................................................................8

Konteks Penilaian........................................................................................................9

Aspek Penting Penilaian..............................................................................................9

Keterkaitan dengan Unit Lain.....................................................................................10

Kompetensi Kunci yang akan Didemonstrasikan dalam Unit Ini................................10

Tingkat Kemampuan yang Harus Ditunjukkan dalam Menguasai Kompetensi ini.....10

BAB 4 STRATEGI PENYAJIAN.......................................................................................11

A Rencana Materi..................................................................................................11

B Cara Mengajarkan Standar Kompetensi............................................................13

C Materi Pendukung untuk Pelatih........................................................................21

Environmental Concerns............................................................................................60

Conclusions................................................................................................................60

BAB 5 CARA MENILAI UNIT INI.......................................................................................84

Apa yang Dimaksud dengan Penilaian ?...................................................................84

Apa yang Dimaksud dengan Kompeten?..................................................................84

Pengakuan Kompetensi yang Dimiliki........................................................................84

Kualifikasi Penilai.......................................................................................................84

Ujian yang Disarankan...............................................................................................85

Checklist yang Disarankan Bagi Penilai....................................................................91

Lembar Penilaian.......................................................................................................92

Indonesia Australia Partnership for Skills Development Batam Institutional Development Projectdocument.doc

Bab 1 Pengantar

BAB 1 PENGANTAR

Selamat Berjumpa di Buku Pedoman ini !

Buku Paket Pembelajaran dan Penilaian ini menggunakan sistem pelatihan berdasarkan kompetensi untuk mengajarkan keterampilan ditempat kerja, yakni suatu cara yang secara nasional sudah disepakati untuk penyampaian keterampilan, sikap dan pengetahuan yang dibutuhkan dalam suatu proses pembelajaran. Penekanan utamanya adalah tentang apa yang dapat dilakukan seseorang setelah mengikuti pelatihan. Salah satu karakteristik yang paling penting dari pelatihan yang berdasarkan kompetensi adalah penguasaan individu secara aktual di tempat kerja.

Pelatih harus menyusun sesi-sesi kegiatannya sesuai dengan :

kebutuhan peserta pelatihan

persyaratan-persyaratan organisasi

waktu yang tersedia untuk pelatihan

situasi pelatihan.

Strategi penyampaian dan perencanaan sudah dipersiapkan oleh pelatih untuk peserta pelatihan. Masalah yang disarankan akan memberikan suatu indikasi tentang apa yang harus dicantumkan dalam program tersebut untuk memenuhi/mencapai standar kompetensi.

Strategi pembelajaran dan penilaian yang dipersiapkan dalam unit ini tidaklah bersifat wajib namun digunakan sebagai pedoman. Peserta pelatihan didorong untuk memanfaatkan pengetahuan dan pengalaman industri mereka. Contoh-contoh produk industri lokal atau hasil pengembangan sumber-sumber yang mereka miliki, dapat membantu dalam menyesuaikan materi dan memastikan relevansi pelatihan.

Persyaratan Minimal Kemampuan Membaca, Menulis & Berhitung

Untuk melaksanakan pelatihan secara efektif dan agar dapat mencapai standar kompetensi diperlukan tingkat kemampuan minimal dalam membaca, menulis dan menghitung berikut:

Kemampuan membaca dan menulis

Kemampuan baca, interpretasi dan membuat teks.

Kemampuan menggabungkan informasi untuk dapat menafsirkan suatu pengertian

Kemampuan menghitung

Kemampuan minimal untuk menggunakan matematika dan simbol teknik, diagram dan terminologi dalam konteks umum dan yang dapat diprediksi serta dimungkinkan untuk mengkomunikasikan keduanya yaitu antara matematik dan teknik.

Definisi

Seseorang yang berkeinginan untuk memperoleh kompetensi seharusnya berkenan menamakan dirinya sebagai peserta latih. Dalam situasi pelatihan, anda dapat ditempatkan sebagai siswa, pelajar atau sebagai peserta, sehingga seorang pengajar kompetensi ini adalah sebagai pelatih. Sebaliknya, dalam situasi pelatihan anda juga dapat ditempatkan sebagai guru, mentor, fasilitator atau sebagai supervisor.

Indonesia Australia Partnership for Skills Development Page 1Batam Institutional Development Projectdocument.doc

Bab 1 Pengantar

Berapa Lama Mencapai Kompetensi ?

Dalam sistem pelatihan berdasarkan kompetensi, fokusnya harus tertuju kepada pencapaian suatu kompeterisi/keahlian, bukan pencapaian pada pemenuhan waktu tertentu; dengan demikian dimungkinkan peserta pelatihan yang berbeda memerlukan waktu yang berbeda pula untuk mencapai suatu kompetensi tertentu.

Simbol

Dalam keseluruhan paket pelatihan akan kita lihat beberapa simbol. Berikut penjelasan tentang simbol :

Simbol Keterangan

HO Handout ( Pegangan Peserta )

OHTOverhead Transparansi yang dapat digunakan dalam penyampaian materi pelatihan

Penilaian Penilaian kompetensi yang harus dikuasai

Tugas Tugas / kegiatan atau aktivitas yang harus diselesaikan.

Terminologi

Akses dan Keadilan

Mengacu kepada fakta bahwa pelatihan harus dapat diakses oleh setiap orang tanpa memandang umur, jenis kelamin, sosial, kultur, agama atau latar belakang pendidikan.

Penilaian

Proses formal yang memastikan pelatihan memenuhi standar-standar yang dibutuhkan oleh industri. Proses ini dilaksanakan oleh seorang penilai yang memenuhi syarat (cakap dan berkualitas) dalam kerangka kerja yang sudah disetujui secara Nasional.

Penilai

Seseorang yang telah diakui/ditunjuk oleh industri untuk menilai/menguji para tenaga kerja di suatu area tertentu.

Kompeten

Mampu melakukan pekerjaan dan memiliki keterampilan, pengetahuan dan sikap yang diperlukan untuk melaksanakan pekerjaan secara efektif ditempat kerja serta sesuai dengan standar yang sudah ditetapkan.

Pelatihan Berdasarkan Kompetensi

Pelatihan yang berkaitan dengan kemampuan seseorang dalam menguasai suatu kompetensi/ keahlian secara terukur dan mengacu pada standar yang sudah ditetapkan.

Aspek Penting Penilaian


Bab 1 Pengantar

Menerangkan fokus penilaian dan poin-poin utama yang mendasari suatu penilaian.

Konteks Penilaian

Menetapkan dimana, bagaimana dan dengan metode apa penilaian akan dilaksanakan.

Elemen Kompetensi

Elemen atau Sub-Kompetensi adalah keterampilan-keterampilan yang membangun suatu unit kompetensi.

Acuan Penilaian

Acuan penilaian adalah garis pedoman tentang bagaimana sebuah unit kompetensi harus dinilai.

Adil

Tidak merugikan para peserta tertentu.

Fleksibel

Tidak ada pendekatan tunggal terhadap penyampaian dan penilaian unjuk kerja dalam sistem pelatihan berdasarkan kompetensi.

Penilaian Formatif

Kegiatan penilaian berskala kecil yang dilakukan selama pelatihan, yaitu untuk membantu dalam memastikan bahwa pelajaran dilaksanakan secara baik dan adanya umpan balik kepada peserta tentang kemajuan yang mereka capai.

Kompetensi Kunci

Kompetensi yang menopang seluruh unjuk kerja dalam suatu pekerjaan. Ini meliputi: mengumpulkan, menganalisis, mengorganisasikan dan mengkomunikasikan ide-ide dan informasi, merencanakan dan mengorganisasikan aktifitas, bekerja dengan orang lain dalam sebuah tim, memecahkan masalah penggunaan teknologi, menggunakan ide-ide teknik-matematis .

Kompetensi-kompetensi ini digolongkan ke dalam tingkat yang berbeda sebagai berikut:

Strategi Penyajian

Strategi penyajian adalah dengan menyediakan informasi yang diperlukan tentang bagaimana melaksanakan pelatihan berdasarkan program yang dilaksanakan di tempat kerja dan/atau di tempat pelatihan/ organisasi yang bersangkutan.

Keterkaitan dengan Unit Lain


Tingkat kemampuan yang harus ditunjukkan dalam menguasai kompetensi ini

Tingkat Karakteristik

1 Tugas-tugas rutin dalam prosedur sudah tercapai dan secara periodik kemajuannya diperiksa oleh supervisor.

2 Tugas-tugas yang Iebih luas dan lebih kompleks dengan peningkatan kemampuan diri untuk menangani pekerjaan secara otonomi. Supervisor melakukan pemeriksaan atas penyelesaian pekerjaan.

3 Bertanggung jawab atas aktifitas-aktifitas yang kompleks dan non-rutin yang diarahkan dan bertanggung jawab atas pekerjaan orang lain.

Bab 1 Pengantar

Menerangkan peran suatu unit dan tempatnya dalam susunan kompetensi yang ditetapkan oleh industri. Hal ini juga memberikan pedoman tentang unit lain yang dapat dinilai bersama.

Standar Kompetensi Nasional

Kompetensi-kompetensi yang sudah disepakati secara nasional dan standar-standar penampilan kerja yang dijadikan acuan oleh segala pihak dalam melakukan suatu pekerjaan.

Kriteria Unjuk kerja

Kriteria-kriteria atau patokan yang digunakan untuk menilai apakah seseorang sudah mencapai suatu kompetensi dalam suatu unit kompetensi.

Variabel

Penjelasan tentang rincian tempat pelatihan dengan perbedaan konteks yang mungkin dapat diterapkan pada suatu unit kompetensi tertentu.

Reliabel

Menggunakan metode-rnetode dan prosedur-prosedur yang menguatkan terhadap standar kompetensi dan tingkatannya diinterpretasikan serta diterapkan secara konsisten kepada seluruh konteks dan seluruh peserta pelatihan.

Valid

Penilàian terhadap fakta-fakta dan kriteria unjuk kerja yang sama akan menghasilkan hasil akhir penilaian yang sama dari penilai yang berbeda.

Pengakuan Kemampuan yang Dimiliki (RCC- Recognition of Current Competence)

Pengakuan akan keterampilan, pengetahuan dan kemampuan sesseorang yang telah dicapainya. (lihat RPL)

Pengakuan Terhadap Pengalaman Belajar (RPL- Recognition of Prior Learning)

Pengakuan terhadap hasil belajar sebelum mempelajari suatu unit kompetensi untuk mendukung pencapaian unit kompetensi tersebut. Hal tersebut biasanya adalah kompetensi yang berkaitan dengan standar kompetensi industi dan juga berkaitan dengan pembelajaran dan pelatihan sebelumnya. (lihat RCC)

Penilaian Sumatif

Penilaian ini dilakukan setetah pelatihan unit kompetensi selesai, yakni untuk memastikan bahwa peserta pelatihan sudah mencapai kriteria unjuk kerja.

Peserta

Orang yang menerima / mengikuti pelatihan.

Pelatih

Orang yang memberikan pelatihan.

Pengetahuan dan Keterampilan Pokok

Definisi atau uraian tentang keterampilan dan pengetahuan yang dibutuhkan untuk mencapai suatu keahlian/keterampilan pada tingkat yang telah ditetapkan

Deskripsi Unit

Gambaran umum tentang program pembelajaran/ kompetensi yang hendak dicapai.


Bab 2 Arahan Bagi Pelatih

BAB 2 ARAHAN BAGI PELATIH

Peran PelatihSalah satu peran anda sebagai pelatih atau guru adalah memastikan standar pelayanan yang tinggi melalui pelatihan yang efektif. Untuk memastikan bahwa anda siap bekerja pada kompetensi ini dengan peserta pelatihan, pertimbangkanlah pertanyaan-pertanyaan berikut ini:

Seberapa yakin anda tentang pengetahuan dan ketrampilah anda sendiri yang dibutuhkan untuk menyampaikan setiap elemen?

Apakah ada informasi atau peraturan baru yang mungkin anda butuhkan untuk diakses sebelum anda memulai pelatihan?

Apakah anda merasa yakin untuk mendemonstrasikan tugas-tugas praktik?

Apakah anda akan sanggup menerangkan secara jelas tentang pengetahuan pendukung yang dibutuhkan oleh peserta pelatihan untuk melakukan pekerjaan mereka secara tepat?

Apakah anda menyadari situasi ruang Iingkup industri dimana kompetensi ini mungkin diterapkan?

Apakah anda menyadari tentang bahasa, kemampuan membaca dan menulis serta keterampilan memahami dan menggunakan matematika peserta pelatihan yang dibutuhkan untuk mendemonstrasikan kompetensi dalam standar kompetensi ini ?

Apakah anda menyadari tentang kemampuan membaca gambar peserta pelatihan yang dibutuhkan untuk mendemonstrasikan kompetensi dalam standar kompetensi ini ?

Sudahkah anda pertimbangkan isu-isu yang wajar dan dapat diterima dalam merencanakan penyampaian program pelatihan ini?

Strategi Penyajian

Variasi kegiatan pelatihan yang disarankan untuk penyampaian kompetensi ini meliputi :

pengajaran ( tatap muka )

tugas-tugas praktik

tugas-tugas proyek

studi kasus

melalui media (video, referensi, dll )

kerja kelompok

bermain peran dan simulasi.

kunjungan/ kerja industri

Pelatih harus memilih strategi pelatihan yang Iayak untuk kompetensi yang sedang diberikan, baik situasi maupun kebutuhan pesertanya. Contohnya, jika praktik industri atau magang tidak memungkinkan, beragam simulasi, demonstrasi dan penggunaan multi media mungkin cukup memadai.

Alat Bantu yang Dibutuhkan untuk Menyajikan Kompetensi Ini

Ruang kelas atau ruang belajar memenuhi syarat minimum untuk penyampaian teori kepada peserta pelatihan, papan tulis, OHP dan perlengkapannya, flip chart dan perlengkapannya, dan alat-alat lain yang diperlukan.


Bab 2 Arahan Bagi Pelatih

Peraturan

Perhatikan peraturan-peraturan atau hukum yang relevan serta panduan yang dapat mempengaruhi kegiatan anda, dan yakinkan bahwa peserta pelatihan anda mengikutinya.

Sumber-sumber untuk Mendapatkan Informasi Tambahan

Sumber-sumber informasi meliputi beberapa kategori berikut ini :

Sumber bacaan yang dapat digunakan :

Judul:

Pengarang:

Penerbit:

Tahun Terbit:

Judul:

Pengarang:

Penerbit:

Tahun Terbit:

Judul:

Pengarang:

Penerbit:

Tahun Terbit:

Judul:

Pengarang:

Penerbit:

Tahun Terbit


Bab 3 Standar Kompetensi

BAB 3 STANDAR KOMPETENSI

Dalam sistem pelatihan, Standar Kompetensi diharapkan dapat menjadi panduan bagi peserta pelatihan atau siswa untuk dapat :

mengidentifikasikan apa yang harus dikerjakan peserta pelatihan

mengidentifikasikan apa yang telah dikerjakan peserta pelatihan

memeriksa kemajuan peserta pelatihan

meyakinkan bahwa semua elemen ( Sub-Kompetensi ) dan kriteria unjuk kerja telah dimasukkan dalam pelatihan dan penilaian.

Judul Unit

Alternative Energy Sources

Deskripsi Unit

This unit describes the various types of alternative energy available. It also examines the reasons why alternative energy systems should be introduced.

Kemampuan Awal

Peserta pelatihan harus telah memiliki kemampuan awal berikut :

Nil

Elemen Kompetensi dan Kriteria Unjuk Kerja

Sub Kompetensi / Elemen Kriteria Unjuk Kerja

1.0 Explain the Need for Alternative Energy Sources.

1.1 Exponential Growth and the Need for Energy Conservation is explained.

1.2 Pollution by coal powered is described.

1.3 The various types of renewable alternative energy sources are described.

2.0 Describe Solar Energy Sytems..

2.1 Solar thermal power energy is described.

2.2 Photovoltaic systems are described.

2.3 Solar chimneys are described.

2.4 Solar ponds are described.

3.0 Describe Wind Energy Systems.

3.1 The basics of wind energy are explained.

3.2 Current wind energy technology is described.

4.0 Desctibe Hydroelectric Energy Systems

4.1 The basics of hydroelectric energy is explained.

4.2 Current hydroelectric energy technology is described.

5.0 Describe Ocean energy Systems

5.1 Ocean thermal energy is described.

5.2 Ocean mechanical energy (Tides) is described.

6.0 Describe Geothermal Energy Systems

6.1 Geothermal electricity production is explained.

6.2 Geothermal direct use is explained.

6.3 Geothermal heat pumps are described.

7.0 Biomass Energy Systems

7.1 Biofuels are explaind.

7.2 Biopower are explaind.


http://zebu.uoregon.edu/2001/ph162/l2.html



Sub Kompetensi / Elemen Kriteria Unjuk Kerja

7.3 Bioproducts are explaind.

8,0 DescribeHydrogen Energy Systems

8.1 Hydrogen as a Source of Energy is explaind.

8.2 Fuel cells are explained.

9.0 Describe Nuclear Energy Systems

9.1. The basics of nuclear energy is explained.

9.2 Nuclear energy technology is described.

10.0 Describe the Various Energy Storage Technologies.

10.1 Pumped Hydroelectric Energy Storag is explaind.

10.2 Flywheels as a Store for Energy are explained.

10.3 Compressed Air Energy Storage (CAES) is explained

10.4 Various types of batteries for energy storage are described.

Variabel

This learning package applies to all sectors of the manufacturing and service industries.

Delivery strategy: Delivery strategies selected must be suitable for both theoretical and/or practical learning outcomes and must reflect the availability of equipment and the needs of the client.

It is recommended that learning and assessment be facilitated in a holistic manner, which may require a learning outcome sequence other than that indicated in the body of this module.

Resource requirements: Useful references include:

Internet sites.

Science magazines.

Audio-Visual materials.

Pengetahuan dan Keterampilan Pokok

Pokok-pokok pengetahuan dan keterampilan yang harus dinilai penguasaan dan penampilannya adalah sebagai berikut :

Need for Alternative Energy Sources

Exponential Growth and the Need for Energy Conservation

Pollution

Types of Renewable Alternative Energy

Solar Energy.

Solar Thermal Power

Photovoltaic Systems

Solar Chimneys

Solar Ponds

Wind Energy

Wind Energy Basics

Wind Energy Technology

Hydroelectric Energy




Hydroelectric Energy Basics

Hydroelectric Energy Technology

Ocean energy

Ocean Thermal Energy

Ocean Mechanical Energy (Tides)

Geothermal Energy

Geothermal Electricity Production

Geothermal Direct Use

Geothermal Heat Pumps

Bio-mass Energy

Bio-fuels

Bio-power

Bio-products

Hydrogen Energy

Hydrogen as a Source of Energy

Fuel cells

Nuclear Energy

Nuclear Energy Basics

Nuclear Energy Technology

Energy Storage Technologies.

Pumped Hydroelectric Energy Storage:

Flywheels as a Store for Energy

Compressed Air Energy Storage (CAES)

Batteries

Konteks Penilaian

Unit ini dapat dilakukan penilaiannya oleh lembaga pelatihan, asosiasi atau industri tempat bekerja. Penilaian seharusnya meliputi penilaian kemampuan praktik/unjuk kerja dan penilaian pokok-pokok pengetahuan dengan beberapa metoda penilaian.

Aspek Penting Penilaian

Fokus penilaian unit ini akan tergantung pada kebutuhan sektor industri yang mencakup dalam program pelatihan, yaitu :

Adanya integrasi antara teori-praktik. Penekanan pelatihan adalah prosedur-prosedur dan teknik-teknik yang

benar disamping hasilnya. Metode-metode penilain sebaiknya terdiri dari proses dan hasil. Aplikasi seharusnya berhubungan dengan kegiatan manufaktur dan

perawatan.

Keterkaitan dengan Unit Lain

Unit ini merupakan unit lanjutan yang membekali pengetahuan dan keterampilan untuk proses las busur manual yang akan dipelajari pada tingkat berikutnya.

Perlu hati-hati dalam pengembangan pelatihan untuk memenuhi persyaratan pelatihan unit ini. Untuk pra-pelatihan kejuruan secara umum, lembaga pelatihan harus menyediakan



program pelatihan yang dapat mencakup semua industri agar tidak terjadi prasangka hanya untuk satu sektor industri saja. Kondisi unjuk bekerja akan membantu memenuhi maksud ini. Sedangkan untuk penyelenggaraan pelatihan bagi industri yang khusus, perlu diupayakan pelatihan khusus juga agar apa yang dibutuhkan industri tersebut dapat dipenuhi.

Kompetensi Kunci yang akan Didemonstrasikan dalam Unit Ini

Kompetensi Umum dalam Unit Ini Tingkat Kompetensi Umum dalam Unit Ini Tingkat

Mengumpulkan, Mengelola dan Menganalisa Informasi

1 Menggunakan Ide-ide dan Teknik Matematika

1

Mengkomunikasikan Ide-ide dan Informasi

1 Memecahkan Masalah 1

Merencanakan dan Mengorganisir Aktifitas-aktifitas

1 Menggunakan Teknologi 1

Bekerja dengan Orang Lain dan Kelompok

1

Tingkat Kemampuan yang Harus Ditunjukkan dalam Menguasai Kompetensi ini

Tingkat Karakteristik

1 Melakukan tugas-tugas rutin berdasarkan prosedur yang baku dan tunduk pada pemeriksaan kemajuannya oleh supervisor.

2 Melakukan tugas-tugas yang Iebih luas dan lebih kompleks dengan peningkatan kemampuan untuk pekerjaan yang dilakukan secara otonom. Supervisor melakukan pemeriksaan atas penyelesaian pekerjaan.

3 Melakukan aktifitas-aktifitas yang kompleks dan non-rutin, yang diatur sendiri dan bertanggung jawab atas pekerjaan orang lain.


Bab 4 Strategi Penyajian A Rencana Materi

BAB 4 STRATEGI PENYAJIAN

A Rencana Materi

Catatan: 1. Penyajian bahan, pengajar, peserta dan penilai harus yakin dapat memenuhi seluruh rincian yang tertuang dalam standar kompetensi.

2. Isi perencanaan merupakan kaitan antara kriteria unjuk kerja dengan pokok-pokok keterampilan dan pengetahuan .

Elemen Jenis Variabel Topik Pelatihan Kegiatan Tampilan

1.0 Mengidentifikasi undang-undang dan peraturan tentang keselamatan dan kesehatan kerja (K3).

1.1 Isi undang-undang No. 1 tahun 1970 tentang keselamatan kerja dijelaskan.

1.2 Peraturan Menteri Tenaga Kerja RI No. Per.03/MEN/1998 tentang tata cara pelaporan dan pemeriksaan kecelakaan dijelaskan.

1.3 Peraturan Menteri Tenaga Kerja RI No. Per.05/MEN/1996 tentang Sistem Manajemen Keselamatan dan Kesehatan Kerja dijelaskan

Undang-undang dan peraturan tentang Keselamatan dan Kesehatan Kerja (K3) :

- Syarat-syarat keselamatan kerja

- Pengawasan dan Pembinaan keselamatan dan kesehatan kerja

- Hak dan kewajiban tenaga kerja dan pengurus.

-Tata cara pelaporan kecelakaan

-Pemeriksaan kecelakaan

-Tujuan, sasaran dan penerapan sistem manajemen K3

- Audit sistem manajemen K3 dan mekanisme pelaksanaan audit

Penyajian

Tanya-jawab

Diskusi

Latihan

Handout

OHT

Tugas

2.0 Mengidentifikasi bahaya di tempat kerja.

2.1 Potensi bahaya di tempat diidentifkasi.

2.2 Beberapa cara untuk mengontrol dan mencegah bahaya diuraikan

Bahaya di Tempat Kerja :

- Jenis-jenis bahaya

- Pencegahan dan pengontrolan bahaya

Penyajian

Tanya jawab

Diskusi

Latihan

Handout

OH

Tugas

3.0 Menjelaskan tata laksana industri.

3.1 Cara tata laksana industri yang baik dapat mengurangi bahaya dijelaskan.

Tata Laksana Industri :

- Tata laksana yang baik

- Penyimpanan bahan

Penyajian

Tanya jawab

Diskusi

Handout

OHT

Tugas


Bab 4 Strategi Penyajian A Rencana Materi

Elemen Jenis Variabel Topik Pelatihan Kegiatan Tampilan

3.2 Maksud gambar simbol keselamatan kerja dijelaskan.

- Gambar simbol keselamatan kerja Latihan

4.0 Menjelaskan polusi pada industri.

4.1 Sumber polusi pada suatu lingkungan industri dijelaskan.

4.2 Tindakan pencegahan dan pengontrolan polusi diuraikan.

Polusi pada Industri :

-Polusi serat dan debu serta pencegahan

- Polusi bahan kimia serta pencegahan.

- Polusi kebisingan serta pencegahan

Penyajian

Tanya jawab

Diskusi

Latihan

Handout

OHT

Tugas

5.0 Menjelaskan keselamatan pribadi.

5.1 Penyebab cedera pribadi dan sikap kerja yang aman diuraikan.

5.2 Prosedur pencegahan dengan perlengkapan pelindung yang tepat diuraikan.

5.3 Tindakan keselamatan dan perlindungan kebakaran dijelaskan

5.4 Prosedur pengungsian dan tindakan pertolongan pertama diterangkan.

Keselamatan Pribadi :

- Tindakan keamanan kerja

- Perlengkapan dan pakaian pelindung serta program ditempat kerja

- Keselamatan dan perlindungan kebakaran

- Prosedur pengungsian darurat

- Pertolongan pertama pada kecelakaan

Penyajian

Tanya jawab

Diskusi

Latihan

Handout

OHT

Tugas


Bab 4 Strategi Penyajian B Cara Mengajarkan Standar Kompetensi

B Cara Mengajarkan Standar Kompetensi

Sesi ini menunjukkan hand-out, tugas / praktik dan transparansi yang cocok/sesuai dengan standar kompetensi.

Keterampilan, pengetahuan dan sikap seperti apakah yang saya inginkan untuk dimiliki siswa.?

Bagaimana saya akan menyampaikan pengetahuan, keterampilan dan sikap kepada siswa?


Instruktur menjelaskan dan memberi tugas tentang maksud dan tujuan undang-undang keselamatan kerja, pasal demi pasal.

Tugas dapat diberikan dalam bentuk latihan dan diskusi

HO 2 s.d. 9

OHT 1 & 2

Tugas 1 s.d. 4


Instruktur menjelaskan dan memberi tugas tentang maksud dan tujuan peraturan tata cara pelaporan dan pemeriksaan kecelakaan, pasal demi pasal.


HO 9 s.d. 13

OHT 3

Tugas 5






Instruktur menjelaskan dan memberi tugas tentang maksud dan tujuan sistem manajemen keselamatan dan kesehatan kerja, pasal demi pasal.


HO 14 s.d. 19

OHT 4

Tugas 6

2.1 Potensi bahaya di tempat diidentifkasi. Instruktur menerangkan dan memberi tugas tentang jenis-jenis bahaya, dan dapat juga memberikan contoh.

Tugas dapat diberikan dalam bentuk latihan, berkunjung dan diskusi

HO 20

OHT 5 & 6

Tugas 7

2.2 Beberapa cara untuk mengontrol dan mencegah bahaya diuraikan.

Instruktur menjelaskan dan memberi tugas tentang pengontrolan dan pencegahan bahaya.






HO 21 s.d. 26

OHT 7

Tugas 8 s.d. 10


Instruktur menjelaskan dan memberikan tugas tentang manfaat tata laksana industri yang baik, juga cara penyimpanan bahan.


HO 27 s.d. 29

OHT 8 & 9

Tugas 11 & 12


Instruktur menerangkan dan memberikan tugas tentang arti gambar simbol keselamatan kerja.


HO 29 & 30

OHT 10





Tugas 13


Instruktur menjelaskan tentang istilah pada polusi dan sumber polusi serta memberi tugas yang relevan.


HO 31 s.d. 34

OHT 11 & 12

Tugas 14 s.d. 16


Instruktur memberikan penjelasan dan memberikan tugas tentang tindakan pencegahan dan pengontrolan polusi.


HO 31 s.d. 34

OHT 12

Tugas 14 s.d. 16


Instruktur menjelaskan istilah tentang keselamatan dan cara kerja yang meyebabkan cedera pribadi. Juga memberikan tugas yang relevan.






HO 35 & 36

OHT 13 s.d. 15

Tugas 17


Instruktur menjelaskan dan memberi tugas tentang jenis-jenis dan fungsi perlengkapan pelindung diri dan persyaratan perlengkapan pada tempat kerja.


HO 36 & 37

OHT 16

Tugas 18


Instruktur memberikan penjelasan tentang tindakan keselamatan dan perlindungan dari kebakaran yang meliputi : jenis alat pemadam, fungsi dan perawatannya, juga kesiapan menghadapi kebakaran. Berikan tugas yang relevan.


HO 37 s.d. 41





OHT 17 & 18

Tugas 19


Instruktur menjelaskan prosedur pengungsian darurat dan tindakan pertolongan pertama, memberikan tugas tentang pengungsian darurat dan pertolongan pertama pada kecelakaan .


HO 41 & 42

OHT 19

Tugas 20 & 21


Bab 4 Strategi Penyajian C Materi Pendukung untuk Pelatih

C Materi Pendukung untuk Pelatih

Materi pendukung bagi guru dibagi dalam tiga hal, yaitu:

1. Lembar Informasi (Handout) : Merupakan pegangan peserta pelatihan yang berisi materi/teori penunjang dan informasi yang sesuai dengan kriteria unjuk kerja yang melingkupinya.

2. Tugas : Merupakan latihan keterampilan praktik yang harus dicapai berkenaan dengan kemampuan yang sesuai dengan rincian kompetensi pada deskripsi unit.

3. Transparansi (Overhead Transparancy /OHT) : Isinya melingkupi setiap kriteria unjuk kerja yang dilengkapi dengan pokok-pokok sajian dan/ atau gambar-gambar yang diperlukan untuk penyampaian materi.


Bab 4 Strategi Penyajian Lembar Informasi

Lembar Informasi

THE NEED FOR ALTERNATIVE ENERGY HO 1

THE NEED FOR ALTERNATIVE ENERGY

The basic concept of alternative energy sources relates to issues of sustainability, renewability and pollution reduction.

In reality, Alternative Energy means any thing other than deriving energy via Fossil Fuel combustion. The basic barrier to all forms of alternative energy lies in initial costs!

Currently we have no significant production line alternative energy source operating anywhere in Indonesia.

The simple problem is that there are simply not enough fossil fuels left to sustain its usage as the foundation of our energy production. Forget about global warming for the moment, the issue is more basic than that.

As the following table shows we have about 50 more years of production from known reserves , after that we will either have to discover more reserves are shift away from our fossil fuel based energy economy.

Table 1: Reserves of Fossil Fuels


http://zebu.uoregon.edu/enhs

http://zebu.uoregon.edu/enhs

http://www.sciam.com/1998/0398issue/0398quicksummary.html


THE NEED FOR ALTERNATIVE ENERGY - Lanjutan HO 2

Exponential Growth

The basic reason that we have a problem is due to exponential growth which creates a strongly non-equilibrium use of our resources.

Its not to great of simplification to state that the failure to understand the concept of exponential growth by planners and/or legislators, is the single biggest problem in all of Environmental Studies and/or Management.

The Two Principle Problems with Energy Management:

Failure for policy makers to understand the concept of exponential growth.

Failure for legislation to be formulated and passed to give us a long term energy strategy

Exponential growth drives resource usage for a very simple reason:

Human population increases exponentially:

Accurate trend extrapolation is the most important part of future planning. However, failure to assume exponential growth will always lead to a disaster so always assume exponential growth when planning anything!

No matter what the growth rate is, exponential growth stars out being in a period of slow growth and then quickly changes over to rapid growth with a characteristic doubling time of:

70/n years; n = % growth rate

Its important to recognize that even in the slow growth period, the use of the resource is exponential. If you fail to realize that, you will run out of the resource pretty fast:

Exhaustion Rate and Timescale of Materials

Material Rate Exhaustion Timescale

Aluminium 6.4% 2007 -- 2023

Coal 4.1% 2092 -- 2106

Copper 4.6% 2001 -- 2020

Petroleum 3.9% 1997 -- 2017

Silver 2.7% 1989 -- 1997

Note: The above estimates include recycling.




POLLUTION CONTROL In Indonesia 89% of our total Energy Budget is Fossil Fuel Based

Fossil Fuel combustion represents a global environmental problem

Most alternative energy sources have little polluting side effects

Clearly, environmental pollution is unavoidable so informed decisions must be made.

Forms of Pollution: Atmosphere - Global: Greenhouse gases

Atmosphere - Global: Acid Rain

Atmosphere - Local: Smog

Groundwater - Local: Nuclear Waste

Surface Water - Local: Oil spills

Thermal Pollution - Local and Global: Waste Heat

Local Land Use: NIMBY - Not in My Back Yard: build that thang over thar

Global Impact of Sources of Energy Generation: Fossil Fuels totally disrupts the Carbon Cycle and is non-equilibrium. Eventually,

enough Carbon Dioxide will be in the atmosphere to effect things seriously. We may, in fact be there already

Solar Energy Intensive use of Land Area due to low efficiency. Significant thermal pollution. For instance, a 1000 MW solar facility would dump 10,000 Megawatts of heat into the local atmosphere.

Hydro The world or Indonesia’s potential has not been fully tapped. No pollution for this but serious alteration of free flowing waterways.

Windpower structural/virtual pollution but not much else

Air Pollution:

Normally the carbon content of fuels (which is high) oxidizes during the combustion process to form CO2 (carbon dioxide). Incomplete combustion leads to the formation of CO:

2C + O2 --> 2CO


http://zebu.uoregon.edu/2001/ph162/images/car2.jpg

http://www.wcmc.org.uk/emergency/

http://zebu.uoregon.edu/2001/ph162/images/sulf.jpg

http://zebu.uoregon.edu/1998/es202/l14.html



Sources of CO pollution: (million tons per year)Source of CO pollution Million tons per year

Motor Vehicles 54

Aircraft 2

Coal 0.7

Fuel Oil 0.1

Industrial Wood Processing 8.8

Forest Fires 6.5

Automobiles dominate because the combustion of gasoline under conditions of high pressure is quite incomplete

The greenhouse effect

Greenhouse gases are a natural part of the atmosphere. They trap the sun's warmth, and maintain the earth's surface temperature at a level necessary to support life.

The problem we now face is that human actions, particularly the burning of fossil fuels (coal, oil and natural gas) and land clearing, are increasing the concentrations of these gases, creating the prospect of global climate change. This is the enhanced greenhouse

Illustration 1

The earth is covered by a blanket of gases which allow light energy from the sun to reach the earth's surface, where it is converted to heat energy. Most of the heat escapes our atmosphere, but some is trapped. This natural effect keeps the earth warm enough to sustain life.

Illustration 2

Human activity such as burning fossil fuels (coal, oil and natural gas) and land clearing is creating more greenhouse gases. This traps more heat, so the earth becomes hotter.




FORMS OF ALTERNATIVE ENERGY:

Solar:

Advantages: Always there; no pollution

Disadvantages: Low efficiency (5-15%); Very high initial costs; lack of adequate storage materials (batteries); High cost to the consumer

Hydro:

Advantages: No pollution; Very high efficiency (80%); little waste heat; low cost per KWH; can adjust KWH output to peak loads; recreation dollars

Disadvantages: Fish are endangered species; Sediment build-up and dam failure; changes watershed characteristics; alters hydrological cycle

Wind:

Advantages: none on large scale; supplemental power in windy areas; best alternative for individual homeowner

Disadvantages: Highly variable source; relatively low efficiency (30%); more power than is needed is produced when the wind blows; efficient energy storage is thus required

Geothermal:

Advantages: very high efficiency; low initial costs since you already got steam

Disadvantages: non-renewable (more is taken out than can be put in by nature); highly local resource

Ocean Thermal Energy Conversion:

Advantages: enormous energy flows; steady flow for decades; can be used on large scale; exploits natural temperature gradients in the ocean

Disadvantages: Enormous engineering effort; Extremely high cost; Damage to coastal environments?

Tidal Energy:

Advantages: Steady source; energy extracted from the potential and kinetic energy of the earth-sun-moon system; can exploit bore tides for maximum efficiency

Disadvantages: low duty cycle due to intermittent tidal flow; huge modification of coastal environment; very high costs for low duty cycle source


http://zebu.uoregon.edu/2001/ph162/images2/ocean.mpg

http://zebu.uoregon.edu/2001/ph162/images/wind.jpg


Forms of Alternative Energy: (lanjutan) HO 6

Hydrogen Burning:

Advantages: No waste products; very high energy density; good for space heating

Disadvantages: No naturally occurring sources of Hydrogen; needs to be separated from water via electrolysis which takes a lot of energy; Hydrogen needs to be liquefied for transport - takes more energy. Is there any net gain?

Biomass Burning:

Advantages: Biomass waste (wood products, sewage, paper, etc) are natural by products of our society; reuse as an energy source would be good. Definite co-generation possibilities. Maybe practical for individual landowner.

Disadvantages: Particulate pollution from biomass burners; transport not possible due to moisture content; unclear if growing biomass just for burning use is energy efficient. Large scale facilities are likely impractical.

Nuclear Fusion:

Forget it, we aren't smart enough yet.

But suppose we become smart enough in a few hundred years. Can adoption of sustainable energy technology get us to this point?



SOLAR ENERGY HO 7

BASICS OF SOLAR ENERGY

The Sun --> Always there; lots of Energy

What Makes the Sun Shine?

Nuclear Fusion; something we may learn how to do later on the Earth and thus solve our Energy Problem.

Question: How many photons (energy) reach the surface of the Earth on Average?

Answer: The energy balance in the atmosphere is shown here:


http://zebu.uoregon.edu/textbook/energygen.html

http://zebu.uoregon.edu/2001/ph162/images/green35.jpg


SOLAR ENERGY - Lanjutan HO 8

The main components in this diagram are the following:

Short wavelength (optical wavelengths) radiation from the Sun reaches the top of the atmosphere.

Clouds reflect 17% back into space. If the earth gets more cloudy, as some climate models predict, more radiation will be reflected back and less will reach the surface

8% is scattered backwards by air molecules:

6% is actually directly reflected off the surface back into space

So the total reflectivity of the earth is 31%. This is technically known as an Albedo . Note that during Ice Ages, the Albedo of the earth increases as more of its surface is reflective. This, of course, exacerbates the problem.

What Happens to the 69% of the incoming radiation that doesn't get reflected back:

19% gets absorbed directly by dust, ozone and water vapour in the upper atmosphere. This region is called the stratosphere and its heated by this absorbed radiation. Loss of stratospheric ozone is causing the stratosphere to cool with time.

4% gets absorbed by clouds located in the troposphere. This is the lower part of the earth's atmosphere where weather happens.

The remaining 47% of the sunlight that is incident on top of the earth's atmosphere reaches the surface. This is not a real significant energy loss.

Note that we measure energy in units of Watt-hours. A watt is not a unit of energy; it is a measure of power.

ENERGY = POWER x TIME

1 Kilowatt Hour = 1KWH = 1000 watts used in one hour = 10 x 100 watt light bulbs left on for an hour

Incident Solar Energy on the ground:

Average over the entire earth = 164 Watts per square meter over a 24 hour day

So the entire planet receives 84 Terrawatts of Power

Our current worldwide consumption is about 10 Terrawatts

Note: 1 Terrawatt = 1,000,000 Mega Watts (check this out)


http://zebu.uoregon.edu/2001/es202/scatter.html



So is this a solution?

There is a large amount of infrastructure (e.g. cost) required to convert from potential to deliverable energy.

8 hour summer day, 40 degree latitude - 600 Watts per sq. meter

So over this 8 hour day one receives:

8 hours x 600 watts per sq. m = 4800 watt-hours per sq. m which equals 4.8 kilowatt hours per sq. m

This is equivalent to 0.13 gallons of gasoline

For 1000 square feet of horizontal area (typical roof area) this is equivalent to 12 gallons of gas or about 450 KWH

But to go from energy received to energy generated requires conversion of solar energy into other forms (heat, electricity) at some reduced level of efficiency.

We will talk more about Photovoltaic cells in detail later. For now the only point to retain is that they are quite low in efficieny!

How Solar Energy is Used:

Two Choices:

Heat Water into Steam

Turn photons into electrons




SOLAR THERMAL POWER.

Fixing of atmospheric Carbon into the biomass photosynthesis is a form of solar collection and energy storage.

The Key to efficient use of solar energy lies in efficient modes of heat transfer. There are three possible modes:

Conduction Transfer of energy via the vibration of atoms in some medium. The best conductors are silver and copper.

Convection Transfer of energy via the bulk motion of a medium (e.g. air, water).

Thermal Radiation Cooling of a material to thermal equilibrium via radiation losses. Stored energy re-emitted (Power per unit Area).

Thermal Conduction:

Heat energy flows from regions of high temperature to low temperature

Wide variation among different materials depends on the density of free electrons in the material

Thermal Conductivity of some Materials in relative Units

MetalsThermal

ConductivityNon-Metals

Thermal Conductivity

Silver 1.0 Concrete 0.004

Copper 0.93 Brick 0.002

Gold 0.70 Wood 0.0002

Aluminum 0.48 Air 0.00005

Steel 0.12

So Clearly metals are required for efficient heat transfer.


http://zebu.uoregon.edu/2001/ph162/images/car2.jpg



Thermal Convection:

Liquids and gases transfer heat this way. The motion of the medium between regions of different temperatures.

Fireplaces produce natural convection warm air rises and is replaced by cold air

Most space heating systems operate via convective heat transfer (forced air)

Thermal Radiation:

Material absorbs sunlight and heats up and then re-radiates that as long wavelength infrared radiation (heat radiation).

Sandstone dwellings and walls would absorb much sunlight during the day and then re-radiate that as heat at night.

In general, recovering incident solar radiation via subsequent thermal radiation of materials is not practical and large amounts of thermal mass are required. This can be a) expensive and b) space intensive.

Thermal Mass:

Efficiency depends upon specific heat of material and its thermal conductivity

Specific Heat is the measure of how much energy a substance can store. This is measured on a scale of 0 to 1. Water has a specific heat of 1.

Thermal conductivity is the measure of efficiency of heat transfer (i.e. getting it back when you want it)

Values for typical materials:

MaterialSpecific

HeatThermal

ConductivityMaterial

Specific Heat

Thermal Conductivity

Water 1.0 4.2 Wood 0.6 1.4

Iron 0.1 320 Brick 0.2 4.6

Glass 0.2 4.0 Concrete 0.15 12

Stone 0.2 3.0

Sand 0.2 2.3

Water is the clear winner followed by concrete. So thermal mass is most effectively used in the form of large tanks of water or several tons of concrete in an insulated container.




Collection of Solar Energy

Amount of captured solar energy depends critically on orientation of collector with respect to the angle of the Sun.

Under optimum conditions, one can achieve fluxes as high as 1000 Watts per sq. meter

In the Winter, for a location at 40 degrees latitude, the sun is lower in the sky and the average flux received is about 300 Watts per sq. meter

A typical household Winter energy use is around 3000 KWHs per month or roughly 100 KWH per day.

Assume our roof top area is 100 square meters (about 1100 square feet).

In the winter on a sunny day at this latitude (40o) the roof will receive about 6 hours of illumination.

So energy generated over this 6 hour period is:

300 watts per square meter x 100 square meters x 6 hours

= 180 KWH (per day) - more than you need.

But remember the efficiency problem:

5% efficiency - 9 KWH per day



At best, this represents 1/3 of the typical daily winter energy usage and it assumes the sun shines on the rooftop for 6 hours that day.

With sensible energy conservation and insulation and south facing windows, its possible to lower your daily use of energy by about a factor of 2. In this case, if solar shingles become 20% efficient, then they can provide 50-75 % of your energy needs

Another example calculation for Solar Energy, which shows that relative inefficiency, can be compensated for with collecting area.

A site in Eastern Oregon receives 600 watts per square meter of solar radiation in July. Assume that the solar panels are 10% efficient and that the are illuminated for 8 hours.

How many square meters would be required to generate 5000 KWH of electricity?

each square meter gives you 600 x.1 = 60 watts

in 8 hours you would get 8x60 = 480 watt-hours or about .5 KWH per square meter

you want 5000 KWH

you therefore need 5000/0.5 = 10,000 square meters of collecting area




PHOTOVOLTAIC SYSTEMS

Charge Generation - Photoelectric Effect

When photons strike a metal, their energy is used to liberate loosely bound electrons and therefore induce a current.

Efficiency of this process depends upon the material

This is the principle behind many digital cameras, otherwise known as CCD cameras . These kinds of cameras are used in astronomy to take digital pictures . Incoming photons are converted into units of electric charge and stored at individual pixel locations. Different amounts of charge represent different intensity levels. This encoded information is a digital image.

To make use of the photoelectric effect, we need material that is a good conductor of electricity and which can be manufactured in bulk at reasonable cost.

This conditions strongly constrain the available choices. For most practical aspects, Silicon is the material of choice.

Silicon:

is abundant on the earth and readily found in the crust. It is a direct product of fusion inside stars. It can be easily recovered from the crust and mass-produced. Computers are cheap because silicon works well for circuit boards and is an easily recoverable material from the earth's crust. The result is a world-wide economy centred around semi-conductor technology.

Has four outer (valence) electrons to bond silicon atoms together in a crystal

Under normal circumstances, there are no free electrons available in silicon to conduct electricity. All the electrons are used to bind the atoms in place to form the crystal.

The conduction band is empty and therefore no current can be carried by the material.


http://zebu.uoregon.edu/2001/ph162/images/m83blue.gif

http://zebu.uoregon.edu/ccd.html

http://zebu.uoregon.edu/ccd.html



Schematic structure of energy bands in Silicon:

Hence, if a silicon atom receives at least 1.11 Electron Volts from some source, a valence electron will move to the conduction band. Once an electron is in the conduction band, the material can carry a current and the material is now a conductor.

So much energy is 1.11 Electron Volts?

1.11 eV corresponds to the energy that a photon of wavelength 1.12 microns has.

77% of the energy from the sun is carried in photons with wavelength less than this and therefore can move a valence electron in silicon into the conducting band

This does not mean that the efficiency of silicon in converting solar photons to electrons is 77%!

Energy Losses:

Photons with energy greater than 1.11 eV heat the crystal

43% of average absorbed photon energy goes into heating

Some photons are reflected by the exposed surface of the crystal

There is some internal resistance in the crystal that inhibits the flow of electrons. This internal resistance increases as the crystal is heated.




Energy Losses (lanjutan)

The efficiency is strongly temperature dependent. As the temperature is raised, the internal resistance of the material increases and the electrical conductivity decreases.

At 0 degrees C silicon has efficiency of 24%

At room temperature the efficiency is 12%

Highest efficiency is achieved (at 0 degrees) in CdTe (Mercate-Telluride) but this is only 28%

The fundamental physical limitation in production photovoltaic cells is then this decrease in efficiency as the temperature of the cell increases. Because of this, for a material like silicon, the operating efficiency of a photovolatic array will probably never be higher than 20% and will most likely be between 5 and 15%.

This doesn't mean that production is not possible. It does mean that relatively large collection areas must be obtained which means high capital costs. If those costs cannot be subsidised, then PV arrays can never be competitive in the commercial energy market place.

To have a production photovoltaic cell, one must mix impurities into silicon (like boron). This will create an internal electric field which will allow the liberated electrons to move down the material.

Over the last 40 years, the effort has gone into increasing the efficiency of PV cells and bringing down the manufacturing costs.

$100 per kilogram of pure silicon. Then the crystals have to be grown in a carefully controlled environment from the molten silicon. Impurities lower overall conductance and reduce the efficiency

Present Costs of solar cells is about $5,000 per Kilowatt compared to $1,000 per Kilowatt from a coal-fired plant.

Typically solar PV cell grids have enough components to produce 20-25 Volts per grid

In California, there are some Production line PV facilities. 350 Megawatts are generated in PV arrays, which are about 11% efficient.

Current Economics:

Consumer cost for energy from newly constructed coal-fired plant in the US ranges from 8-20 cents per KWH

PV power generation would cost the consumer 25-50 cents per KWH.

Costs might be equivalent when pollution from coal is also considered but still, the structure is not here for the consumer to pay the true cost of energy


http://www.energy.ca.gov/development/solar/index.html



Photovoltaic Enbergy System

A typical system might look like this:

The key is to connect facilities to the power grid and sell power to the consumer at a competitive rate:

Current costs are about 25-50 cents per KWH for Solar Generated Electricity

Average price for the country from coal, hydro, nuclear, etc., is about 13 cents per KWH




SOLAR CHIMNEY

Principle

The solar chimney basically operates like a hydroelectric power plant, but instead of water it uses hot air

Beneath a large glass roof air is heated. It enters a vertical tube placed at the center of the roof and creates an updraught there. Inside the tube Kaplan-type wind turbines with electrical generators are producing electricity. Contrary to the power plants with reflecting mirrors, the glass roof collector of a solar chimney also operates with overcast sky, resp. diffuse light - a decisive advantage!

Principle of the solar chimney: glass roof collector, chimney tube, wind turbines.

Continuous 24 hours-operation is guaranteed by placing tight water-filled tubes under the roof. The water heats up during the daytime and emits its heat at night. These tubes are filled only once, no further water is needed.

Principle of heat storage underneath the roof using water-filled black tubes.


Day:Night:

http://www.sbp.de/de/html/projects/solar/aufwind/pages_auf/ak.htm





The Technology

Solar chimneys are large-scale power plants with an output of 5 to 200 MW each. For that the glass roof has to be several kilometres in diameter and the tube has to be as high as possible to achieve a large annual output. A 100 MW plant will produce about 750 GWh/year at 2.300 kWh/m2 global horizontal radiation.

For the chimney we thoroughly compared various types of construction and materials and discovered that for all desert -countries in question reinforced concrete tubes promise the longest life-span at least costs. Technologically speaking they are nothing but cylindrical natural draught cooling towers. For a 100 or 200 MW plant a suitable height would be 1.000 m with a diameter of 130 m. In this case the wall thickness decreases from 99 cm to 25 cm, and stiffening spoked wheels are placed on the inside.

The glass roof is constructed simply of square suspended roof segments say 9m x 9m. A prototype of this type was successfully tested in Spain for several years.

The shrouded turbines are basically more closely related to the pressure-staged hydroelectric turbines than to the speed-stepped wind turbines. Either a large number of small turbines with horizontal axes may be arranged around the base of the chimney, or to be more cost-efficient, one large, say a 100 MW turbine with a vertical axis is placed in the chimney’s cross-section.

Energy production Costs

The cost of a solar chimney is in the glass panels and the turbines. Once operational the costs are quite minimal. The major cost is in the interest bill in building the plant. The building of the plant could take up to four years and wouldn accrue high levels of interest to be paid back in this period.

In contrast to this, in fossil fuel power plants, the variable fuel costs are the deciding factor.

If the money to build the solar chimney can be borrowed at interst rates below 8% then solar chimneys can be competitive to coal firwd plants.




SOLAR PONDS

Principle

A solar pond is a body of water that collects and stores solar energy. Solar energy will warm a body of water (that is exposed to the sun), but the water loses its heat unless some method is used to trap it.

Water warmed by the sun expands and rises as it becomes less dense. Once it reaches the surface, the water loses its heat to the air through convection, or evaporates, taking heat with it.

The colder water, which is heavier, moves down to replace the warm water, creating a natural convective circulation that mixes the water and dissipates the heat.

The design of solar ponds reduces either convection or evaporation in order to store the heat collected by the pond. They can operate in almost any climate.

Types of Solar Ponds

There are two main categories of solar ponds:

Non-convecting ponds, which reduce heat loss by preventing convection from occurring within the pond.

Convecting ponds, which reduce heat loss by hindering evaporation with a cover over the surface of the pond.

Non-convecting Ponds

There are two main types of non-convecting ponds:

Salt Gradient Ponds

A salt gradient pond has three distinct layers of brine (a mixture of salt and water) of varying concentrations. Because the density of the brine increases with salt concentration, the most concentrated layer forms at the bottom. The least concentrated layer is at the surface. The salts commonly used are sodium chloride and magnesium chloride.

A dark-colored material—usually butyl rubber—lines the pond. The dark lining enhances absorption of the sun’s radiation and prevents the salt from contaminating the surrounding soil and groundwater.

As sunlight enters the pond, the water and the lining absorb the solar radiation. As a result, the water near the bottom of the pond becomes warm—up to 200o F (93.3oC).




Although all of the layers store some heat, the bottom layer stores the most. Even when it becomes warm, the bottom layer remains denser than the upper layers, thus inhibiting convection. Pumping the brine through an external heat exchanger or an evaporator removes the heat from this bottom layer. Another method of heat removal is to extract heat with a heat transfer fluid as it is pumped through a heat exchanger placed on the bottom of the pond.

Membrane Ponds.

The membrane pond, inhibits convection by physically separating the layers with thin transparent membranes. As with salt gradient ponds, heat is removed from the bottom layer.

Convecting Pond

Shallow Solar Pond

This pond consists of pure water enclosed in a large bag that allows convection but hinders evaporation. The bag has a blackened bottom, has foam insulation below, and two types of glazing (sheets of plastic or glass) on top.

The sun heats the water in the bag during the day. At night the hot water is pumped into a large heat storage tank to minimize heat loss.

Excessive heat loss when pumping the hot water to the storage tank has limited the development of shallow solar ponds.

Deep, Saltless Pond

This convecting pond differs from shallow solar ponds only in that the water need not be pumped in and out of storage.

Double-glazing covers deep saltless ponds. At night, or when solar energy is not available, placing insulation on top of the glazing reduces heat loss.

Applications

Israel is the elader in this technology and stems have been installed in Australia and the USA.

Applications for solar ponds include:

Community, residential and commercial heating.

Low-temperature industrial and agricultural process heat.

Preheating for higher-temperature industrial process applications.

Electricity generation. – usuualy by use of a Rankine Cycle heat engine (see below).

Heat extracted from ponds can also run absorption chillers.




Rankine Cycle heat engine

Rankine cycle is a heat engine with vapour power cycle. The common working fluid is water. The cycle consists of four processes:

1 to 2: Isentropic expansion (Steam turbine)

2 to 3: Isobaric heat rejection (Condenser)

3 to 4: Isentropic compression (Pump)

4 to 1: Isobaric heat supply (Boiler)

Feasibility

Solar ponds can only be economically constructed if there is an abundance of inexpensive salt, flat land, and easy access to water. Environmental factors are also important. An example is preventing soil contamination from the brine in a solar pond. For these reasons, and because of the current availability of cheap fossil fuels, solar pond development has been limited in Indonesia. The greatest potential market for solar ponds in Inonesia could be in the industrial process heat sectors.


http://www.taftan.com/thermodynamics/ISOBARPR.HTM

http://www.taftan.com/thermodynamics/ISENPROC.HTM

http://www.taftan.com/thermodynamics/WFLUID.HTM

http://www.taftan.com/thermodynamics/HENGINE.HTM


WIND ENERGY HO 22

General

We have been harnessing the wind's energy for hundreds of years. Windmills have been used for pumping water or grinding grain.

Today, the windmill's modern equivalent— a wind turbine— can use the wind's energy to generate electricity.

Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind.

Turbines catch the wind's energy with their propeller-like blades. Usually, two or three blades are mounted on a shaft to form a rotor.

A blade acts much like an airplane wing. When the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift.

The force of the lift is actually much stronger than the wind's force against the front side of the blade, which is called drag. The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity.

Wind turbines can be used as stand-alone applications, or they can be connected to a utility power grid or even combined with a photovoltaic (solar cell) system. For utility-scale sources of wind energy, a large number of wind turbines are usually built close together to form a wind plant. Several electricity providers today use wind plants to supply power to their customers.

Stand-alone wind turbines are typically used for water pumping or communications. However, homeowners, farmers in windy areas can also use wind turbines as a way to cut their electric bills.

Small wind systems also have potential as distributed energy resources. Distributed energy resources refer to a variety of small, modular power-generating technologies that can be combined to improve the operation of the electricity delivery system.

Basics of Wind Energy:

Kinetic Energy of wind is: 1/2 * mass * velocity2

Amount of air moving past a given point (e.g. the wind turbine) per unit time depends on the velocity.

Power per unit area = KE * velocity MV2 x V

So Power that can be extracted from the wind goes as velocity cubed (V3)

Note: The density of air at sea level is approximately 1/800th the density of water, that is approximately 1.25 kg/m3



WIND ENERGY - Lanjutan HO 23

The power on the windmill is proportional to the kinetic energy transfer per unit time as well as the density of the air (which is represented by the mass of the air above).

Power proportional to v3 is very important. 27 times more power is in a wind blowing at 60 kph than one blowing at 20 kph

For average atmospheric conditions of density and moisture content:

Power per sq. meter = 0.0006 V3

Where:

Velocity is measured in metres per second

Power is measured in Kilowatts

Note: 1 metre per second is 3.6 kph

How much energy is there in a 35 kph wind?

35 kph wind = 9.7 m/s x 0006 * 103 = 0.0006 * 9.73 = 0.55 Kilo watts per square meter

= 550 watts per square meter

Windmill Efficiency

Windmills cannot operate at 100% efficiency because the structure itself impedes the flow of the wind. The structure also exerts back-pressure on the turbine blades as they act like an air foil (a wing on an airplane).

In most all cases, the efficiency of the wind turbine depends on the actual wind speed. For the three-blade design the efficiency curve looks like this:


0 5 10 15 20 25

Windspeed (m/s)

44%

Windspeed (m/s) Vs Efficiency (%)

Efficiency


WIND ENERGY - Lanjutan HO 24

The maximum efficiency of 44% is reached in a 9 m/s wind (30 kph) and falls sharply at higher wind speeds. For a reasonable range of winds, the average effiency is around 20%,

Because the power goes as v3, there is no real need to optimize design for highest efficiency at highest windspeed because the power capacity in the wind will greatly exceed that which can be obtained by the generator.

Theoretical maximum efficiency is 59%

Picaresque Dutch Windmill (4=arms) = 16%

Rotary, multiblade = 30%

High speed propeller (vertical) = 42%

Two blade horizontal = 45%

Rotary type windmills have high torque and are useful for pumping water. High torque means efficient operation at low wind speeds.

High speed propeller types have low torque and are most efficient at high rotational velocities useful for generation of electricity

Example calculation:

Windmill efficiency = 42%

Average wind speed = 10 m/s (36 kph)

Power = 0.0006 x 0.42 x 1000 = 250 Watts per square meter

Electricity generated is then .25 KWH per sq. meter

If wind blows 24 hours per day then annual electricity generated would be about 2200 KWH per sq. meter

But, on average, the wind velocity is only this high about 10% of the time

Typical annual yield is therefore 200-250 KWH per sq. meter

To Generate 10,000 KWH annual then from a 35 kph wind that blows 10% of the time

Windmill area = 10,000 KWH/220 KHW per sq. meter = 45 sq meters

This is a circular disk of diameter about 8 meters

This is not completely out of the question for some homes

Even a small windmill (2 meters) can be effective:

35 kph 10% of the time 2500 KWH annually



Therefore 4 small windmills (2 metres) operating at 35 kph 10% of the time produce 10000 KWH annually



HYDROELECTRIC ENERGY HO 25

Introduction to Hydroelectric Energy

Flowing water creates energy that can be captured and turned into electricity. This is called hydroelectric power or hydropower.

The most common type of hydroelectric power plant uses a dam on a river to store water in a reservoir. Water released from the reservoir flows through a turbine, spinning it, which in turn activates a generator to produce electricity. But hydroelectric power doesn't necessarily require a large dam. Some hydroelectric power plants just use a small canal to channel the river water through a turbine.

Another type of hydroelectric power plant— called a pumped storage plant— can store power. The power is sent from a power grid into the electric generators. The generators then spin the turbines backward, which causes the turbines to pump water from a river or lower reservoir to an upper reservoir, where the power is stored. To use the power, the water is released from the upper reservoir back down into the river or lower reservoir. This spins the turbines forward, activating the generators to produce electricity.

A small or micro-hydroelectric power system can produce enough electricity for a home, farm, or ranch.

Hydrologic Cycle

Hydropower plants take advantage of a naturally occurring, continuous process -- the process that causes rain to fall and rivers to rise. Every day, our planet loses a small amount of water through the atmosphere as ultraviolet rays break water molecules apart. But at the same time, new water is emitted from the inner part of the Earth through volcanic activity. The amount of water created and the amount of water lost is about the same.

At any one time, the world's total volume of water is in many different forms. It can be liquid, as in oceans, rivers and rain; solid, as in glaciers; or gaseous, as in the invisible water vapor in the air. Water changes states as it is moved around the planet by wind currents. Wind currents are generated by the heating activity of the sun. Air-current cycles are created by the sun shining more on the equator than on other areas of the planet.

Air-current cycles drive the Earth's water supply through a cycle of its own, called the hydrologic cycle. As the sun heats liquid water, the water evaporates into vapor in the air. The sun heats the air, causing the air to rise in the atmosphere. The air is colder higher up, so as the

water vapor rises, it cools, condensing into droplets. When enough droplets accumulate in one area, the droplets may become heavy enough to fall back to Earth as precipitation.


http://people.howstuffworks.com/sun.htm

http://people.howstuffworks.com/volcano.htm


HYDROELECTRIC ENERGY - Lanjutan HO 26

The hydrologic cycle

The hydrologic cycle is important to hydropower plants because they depend on water flow. If there is a lack of rain near the plant, water won't collect upstream. With no water collecting up stream, less water flows through the hydropower plant and less electricity is generated.

Why is Hydro so attractive?

BECAUSE ITS CHEAP! for the consumer average price in the PNW is 450 Rp. per KWH this is at least 50% of the national average!

Low cost to the consumer. This reflects the relatively low operating costs of the Hydro Facility. Most of the cost is in building the dam

Operating costs about 55 Rp. per KWH

Coal Plant averages around 200 Rp. per KWH, which reflects costs of mining, transport and distribution.




Energy density in stored elevated water is high:

One litre of water per second,from 90 metres, on a turbine generates 720 watts of power. If this power can be continuously generated for 24 hours per day for one month then the total number of KWH per month is then:

720 watts x 24 hours/day x 30 days/month = 518 KWH/month.

Power generating capacity is directly proportional to the height the water falls (Potential energy = mgh). For a fall of say only 3 m, 30 times less electricity would be generated (e.g. 17 KWH/month) - but this is just for a miniscule flow rate of 1 kg/sec.

Basic Components of a Conventional Hydropower Plant

Dam - Most hydropower plants rely on a dam that holds back water, creating a large reservoir. Often, this reservoir is used as a recreational lake.

Intake - Gates on the dam open and gravity pulls the water through the penstock, a pipeline that leads to the turbine. Water builds up pressure as it flows through this pipe.

Turbine - The water strikes and turns the large blades of a turbine, which is attached to a generator above it by way of a shaft. The most common type of turbine for hydropower plants is the Francis Turbine, which looks like a big disc with curved blades. A turbine can weigh as much as 172 tons and turn at a rate of 90 revolutions per minute (rpm), according to the Foundation for Water & Energy Education (FWEE).

Generators - As the turbine blades turn, so do a series of magnets inside the generator. Giant magnets rotate past copper coils, producing alternating current (AC) by moving electrons. (You'll learn more about how the generator works later.)


http://people.howstuffworks.com/framed.htm?parent=hydropower-plant.htm&url=http://www.fwee.org/gen.html

http://people.howstuffworks.com/framed.htm?parent=hydropower-plant.htm&url=http://www.atals.com/newtic/hyd_tbfr.htm

http://people.howstuffworks.com/question232.htm



Transformer - The transformer inside the powerhouse takes the AC and converts it to higher-voltage current.

Power lines - Out of every power plant come four wires: the three phases of power being produced simultaneously plus a neutral or ground common to all three. (Read How Power Distribution Grids Work to learn more about power line transmission.)

Outflow - Used water is carried through pipelines, called tailraces, and re-enters the river downstream.

The water in the reservoir is considered stored energy. When the gates open, the water flowing through the penstock becomes kinetic energy because it's in motion. The amount of electricity that is generated is determined by several factors. Two of those factors are the volume of water flow and the amount of hydraulic head. The head refers to the distance between the water surface and the turbines. As the head and flow increase, so does the electricity generated. The head is usually dependent upon the amount of water in the reservoir.

Inside the Generator

The heart of the hydroelectric power plant is the generator. Most hydropower plants have several of these generators.

The generator, as you might have guessed, generates the electricity. The basic process of generating electricity in this manner is to rotate a series of magnets inside coils of wire. This process moves electrons, which produces electrical current.


http://people.howstuffworks.com/power.htm

http://people.howstuffworks.com/power.htm



Each generator is made of certain basic parts:

Shaft

Excitor

Rotor

Stator

As the turbine turns, the excitor sends an electrical current to the rotor. The rotor is a series of large electromagnets that spins inside a tightly-wound coil of copper wire, called the stator. The magnetic field between the coil and the magnets creates an electric current.

In a typical large dam e.g. Hoover Dam, a current of 16,500 volts moves from the generator to the transformer, where the current ramps up to 230,000 volts before being transmitted.

Hydrologic Cycle

Hydropower plants take advantage of a naturally occurring, continuous process -- the process that causes rain to fall and rivers to rise. Every day, our planet loses a small amount of water through the atmosphere as ultraviolet rays break water molecules apart. But at the same time, new water is emitted from the inner part of the Earth through volcanic activity. The amount of water created and the amount of water lost is about the same.

At any one time, the world's total volume of water is in many different forms. It can be liquid, as in oceans, rivers and rain; solid, as in glaciers; or gaseous, as in the invisible water vapor in the air. Water changes states as it is moved around the planet by wind currents. Wind currents are generated by the heating activity of the sun. Air-current cycles are created by the sun shining more on the equator than on other areas of the planet.

Air-current cycles drive the Earth's water supply through a cycle of its own, called the hydrologic cycle. As the sun heats liquid water, the water evaporates into vapor in the air. The sun heats the air, causing the air to rise in the atmosphere. The air is colder higher up, so as the water vapor rises, it cools, condensing into droplets. When enough droplets accumulate in one area, the droplets may become heavy enough to fall back to Earth as precipitation.


http://people.howstuffworks.com/sun.htm

http://people.howstuffworks.com/volcano.htm

http://people.howstuffworks.com/electromagnet.htm


*

OCEAN ENERGY HO 30

Introduction to ocean energy

The ocean can produce two types of energy:

Thermal energy from the sun's heat, and

Mechanical energy from the tides and waves.

Oceans cover more than 70% of Earth's surface, making them the world's largest solar collectors. The sun's heat warms the surface water a lot more than the deep ocean water, and this temperature difference creates thermal energy. Just a small portion of the heat trapped in the ocean could power the world.

Ocean thermal energy

Ocean thermal energy is used for many applications, including electricity generation. There are three types of electricity conversion systems:

Closed-cycle systems use the ocean's warm surface water to vaporize a working fluid, which has a low-boiling point, such as ammonia. The vapor expands and turns a turbine. The turbine then activates a generator to produce electricity.

Open-cycle systems actually boil the seawater by operating at low pressures. This produces steam that passes through a turbine/generator.

Hybrid systems combine both closed-cycle and open-cycle systems.

More promising technology is OTEC (Ocean Thermal Energy Generation). This takes advantage of the fact that the ocean is an enormous heat engine.

Physics of Heat Engines:

Efficiency = work done/energy input

It can be shown that this is equivalent to

efficiency (in %) = 1 - T1/T2 ; T1 < T2

T is measured in Kelvins

So, in principle any two reservoirs with different temperatures T1 and T2 can produce energy. There will be a demonstration of this principle in class today.

Boiling water T = 373oK

Ice Water T = 273oK

Liquid Nitrogen T = 77oK

Efficiency of Boiling water and Ice water: 1 - (273/373) = 27%

Efficienty of Ice water and LN2: 1 - (77/273) = 72%

What is efficiency of Boiling water and LN2?


http://zebu.uoregon.edu/2001/ph162/kelvin.txt


OCEAN ENERGY - Lanjutan HO 31

Thermodynamic Constraints:

Systems are in equilibrium when they are at the same temperature

Energy is conserved within a closed system

It is not possible to extract heat energy from a reservoir and perform work without transferring heat to a reservoir of lower temperature. In other words, all thermodynamic systems must tend towards equilibrium. Some energy goes towards performing work and some is lost as waste heat.

To get the highest efficiency one wants to maximize the difference between T1 and T2 but then their are material problems (containers melt, freeze, etc)

Typical Case:

Coal-fired burner: T = 825oK

Cooling tower: T = 300oK

Efficiency = 1 – 300/825 = 64%

How this all works:

Exhaust steam is condensed back into liquid thereby decreasing its total volume by a factor of 1000

Therefore the work done by the pump is down by a factor of 1000 compared to if it had to pump steam directly back into the system




Heat Energy from the Ocean

Basic principle is that heat difference is used to condense a steam into a liquid then return it to be reheated.

Since heat differences in the ocean will be smaller, and then one must substitute ammonia for water as the working fluid.

Example Calculations:

Surface Ocean temperature is 25 degrees C (298K)

At 1000 meters depth the temperature is 5 degrees C (278K)

Efficiency = 1 - 278/298 = 0.067 (6.7%)

Power in cooling 1000 gallons of water per second by 2 degrees C is 32 MegaWatts (because water has such high heat capacity/storage)

Using 6.7% efficiency would then yield 2 Megawatts (1/500 typical coal-fired plant)

But this is only for 1000 measly little gallons per second




OTEC (Ocean Thermal Energy Conversion) Potential Sites:

Florida, Puerto Rico, and Hawaii

Indian Ocean

Northeast Australia, Indonesia and Mexico

Above sites typically have thermal gradients higher then 22 degrees C

Energy extracted comes from the cooling of the warmer water this is transferred to the ammonia that does the actual work of turning the turbine (as ammonia steam)

Energy extracted proportional to the volume of water and the temperature it drops.

Principal energy loss is when the warmer water meets the cooler water in the condenser.

Review of OTEC

Thermal gradients of greater than 22 C can be exploited and used as a heat engine

Energy is derived from cooling warm surface water to the temperature of the water at approximately 500-1000 feet depth.

The maximum surface temperature of ocean water is 25 C and its minimum value is of course 0 C

Efficiency is then 1 -(273+0)/(273+25) = 1 - 273/298 = 7%

Energy is derived from the cooling water via transfer to a working fluid such as ammonia which when mixed with warm water vaporizes to steam and powers a turbine

Ammonia returns (condenses) to liquid when mixed with cooler water at depth and then the cycle repeats itself

Since the volume of water in the oceans is huge, the capacity in just the seas of Indonesia alone is several 10's of Giga


http://mano.icsd.hawaii.gov/dbedt/ert/otec_hi.html



Ocean mechanical energy

Ocean Power also comes in 2 other forms:

Tidal Energy

Current Flow Energy

Tidal energy

The ocean is a huge reservoir for storing the energy of the sun that is incident on the earth. How huge is huge?

Incident flux on ocean surface area is 1017 Watts or 0.1 Billion Billion Watts (its a large number)

The oceans are a huge heat engine. Temperature differences, caused by differences in insolation both in latitude and in depth.

Equatorial waters warmer than higher latitude waters

surface layers warmer than deeper layers

This sets up an enormous circulationps network

Major currents are shaped by:

Temperature differences (driven mostly by tilt of earth's axis)

Prevailing wind patterns interacting with the surface waters (again driven mostly by tilt of earth's axis)

the rotation of the earth the Coriolis Force

shorelines of continental masses

Tapping the Current for Energy:


http://zebu.uoregon.edu/2001/ph162/wmaps/ocean.mpg

http://www.bluenergy.com/



Tidal Energy from the Ocean

Extracts energy from the kinetic energy of the earth-moon-sun system.

Variations in water level along coastlines can be used to drive turbines technology is the same as low-head hydro power

Vertical tides on US coast range from 2 feet in Florida to more than 18 feet in Maine

To enhance efficiency of turbines driven by tidal currents, it is desirable to build a dam-like structure across the mouth of a tidal basin in order to direct the flow to a turbine

Turbines designed for work at both high and low tide (inflow or outflow)

Intermittent tidal flow is major problem. Tidal facility produces about 1/3 the electrical energy of a hydro facility of the same peak capacity

Two tidal plants in the world:

1 MW facility on the White Sea in Russia (1969)

240-MW on the Rance River, St. Malo France (1967) has 750-meter long dike to impound tides that can be as high as 13 meters (!)



GEOTHERMAL ENERGY HO 36

GEOTHERMAL ENERGY

Geothermal energy is energy recovered from the heat of the earth's core. In nature, geothermal heat shows up in the form of volcanoes, hot springs and geysers.

For thousands of years, humans have used naturally occurring hot springs for bathing. More recently, geothermal energy has been used to generate electricity, and to provide heat for homes and industries.

Geothermal energy is a versatile and reliable source of heat and electricity which generally produces none of the greenhouse gases associated with the combustion of fossil fuels.

The high temperatures in the earth's core are a result of heat trapped during the formation of the earth approximately 4.7 billion years ago, as well as the decay of naturally occurring radioactive elements.

The rate of heat flow out of the earth is about 5,000 times smaller than the rate of solar energy reaching the earth's surface. Solar radiation therefore controls the surface temperature of the planet; but a few meters below the earth's surface, temperatures are governed by the internal heat of the earth.

Geothermal energy is often considered a renewable source of energy. This is not strictly true, because human uses of geothermal generally remove the heat from a location faster than it is replaced.

The magnitude of the geothermal resource is so large, however, that on a human time scale it may be considered as a renewable energy source.

The Geothermal Resource

The temperature of the earth's crust rises as the depth from the surface increases, all over the world. In some places the rate of this increase in temperature, the "geothermal gradient", is higher than in others.

These areas tend to be located in regions that are geologically active, where sections of the earth's crust are either colliding or moving apart (Figure 1). Due to this fact, the most promising geothermal resources are located in areas of volcanic activity.

The higher the geothermal gradient, the less expensive it is to extract heat from the earth, due to drilling and pumping costs. In the ultimate case, the gradient may be so high that naturally occurring surface waters have been heated to a useful temperature. This is the case with hot springs and geysers.



GEOTHERMAL ENERGY - Lanjutan HO 37

Geothermal energy can be usefully extracted from four different types of geologic formations. These include hydrothermal, geopressurized, hot dry rock and magma. Each of these different reservoirs of geothermal energy can potentially be tapped and used for heating or electricity generation.

Different extraction and processing techniques are required for the different sources of geothermal heat. In addition to the above, heat pumps can be used to extract low temperature heat from shallow depths. Such heat pumps are similar to the air-to-air heat pumps commonly used to heat homes, and will not be examined in detail.

Hydrothermal reservoirs Hydrothermal reservoirs contain hot water and/or steam trapped in fractured or

porous rock formations by a layer of impermeable rock on top.

Hydrothermal reservoirs have been the most common source of geothermal energy production worldwide.

Geopressurized resources are from formations where moderately high temperature brines are trapped in a permeable layer of rock under high pressures.

These brines often contain dissolved methane which can potentially be extracted for use as a fuel.

Hot dry rock Hot dry rock is another potential geothermal resource. Hot dry rock reservoirs are

generally hot impermeable rocks at depths shallow enough to be accessible (<3,000 m). To extract heat from such formations, the rock must be fractured and a fluid circulation system developed.

Although hot dry rock resources are virtually unlimited in magnitude around the world, only those at shallow depths are currently economical. The final source of geothermal energy is magma, which is partially molten rock at very high temperatures (>600°C).

The theoretical potential of the world's geothermal energy resource is enormous. There is enough heat in the earth's core to provide all of the world's energy needs for thousands of years. Unfortunately, most of this heat is at such great depths below the surface that it is extremely expensive or impossible to extract. Accessible geothermal energy is also not evenly distributed around the globe.

The result of the above facts is that geothermal energy is currently being exploited only in those regions where heat is available near the surface, such as "The Geysers" in California where 1,866 million watts (MW) of electricity are generated. Other locations with extensive use of geothermal energy include Reykjavikand Rotorua in Iceland where shallow reservoirs of subterranean steam are tapped to provide heating and hot water for many buildings. In all cases, individual reservoirs from which heat is extracted will eventually cool to the extent that they are no longer useful. This forces new or deeper wells to be drilled, increasing the costs of geothermal energy.




Geothermal Energy Technologies

Geothermal energy can either be used directly as heat for a district heating system or industrial process, or, if the temperature is high enough, converted into electricity. Unlike other renewable sources of electricity, geothermal power is not intermittent. It provides a reliable source of electricity 24 hours a day. The technology required to extract geothermal energy depends upon the type of the geothermal reservoir and the end use. Technologies for producing electricity from the four types of geothermal resources outlined above, will be looked at in detail. Using geothermal energy directly for heating involves the same heat extraction stages, but eliminates the need for a turbine and generator.

Hydrothermal reservoirs containing high temperature steam are the simplest source of geothermal electricity. Two holes or wells are drilled into the formation containing the steam. The steam is drawn out of one of the wells (the "production well") and allowed to pass through a standard turbine such as those used at thermal electricity generating stations (Figure 2). After passing through the turbine and thus turning a generator, the steam is condensed and returned to the rock formation through the second, "injection well". Returning the condensed liquid into the ground maintains a supply of geothermal fluids in the reservoir.

FIGURE 2: Schematic of a Geothermal Electricity Generating System for Vapor-Dominated Hydrothermal Resources (59K).

Hydrothermal and geopressurized reservoirs containing very hot water rather than steam are exploited in a similar fashion; but the hot water must first be "flashed" into steam as its pressure is reduced above the ground. Pumps are required to extract the water from hydrothermal reservoirs, while geopressurized systems often do not require a pump. Variations on the above technology include systems where steam is passed through two successive turbines, called a "double flash". The more expensive double flash systems capture more of the energy of the geothermal fluid and are therefore 10 to 20 percent more efficient than single flash plants.

Electricity production from lower temperature (<190°C) hydrothermal and geopressurized sources is generally accomplished through the use of "binary cycle technology". Binary cycle geothermal power plants pass lower temperature geothermal fluids through a heat exchanger to heat a working fluid such as iso-butane. Iso-butane has a lower boiling temperature and quickly vaporizes to power a turbine. Although this type of system is less efficient and more expensive than the single and double flash technologies, lower temperature geothermal resources can be exploited and the geothermal fluids are never released into the atmosphere. Methane can also be extracted from some geopressurized brines and used to generate additional power.


http://www.iclei.org/EFACTS/geofig2.gif




Hot dry rock (HDR) geothermal reservoirs are tapped by drilling two long boreholes and then fracturing the rock at whatever depth it is hot enough to provide useful amounts of energy. Water is pumped down one hole and comes up the other at an elevated temperature (Figure 3). Most HDR resources provide water at moderate temperatures (200°C), suitable for heating or use in a binary cycle power plant. Magma, or molten rock geothermal resources are very high temperature sources of geothermal energy. Although there is currently no existing technology for recovering heat from magma, it is a source of large amounts of energy when the magma is at reasonable depths.

FIGURE 3: As Hot Dry Rock (HDR) Geothermal Systems Concept for Low-Permeable Formations (90K).

Environmental Concerns

Although geothermal energy generally results in negligible greenhouse gas emissions, it is not without environmental impacts. The main environmental concern with geothermal energy is the result of natural contaminants dissolved in the water or brine extracted from the ground. Silica, sulfates, sulfides, carbonates, silicates and halides present in geothermal fluids present problems for both equipment and the environment. Hydrothermal and geopressurized water and brines are often very corrosive. This complicates the choice of materials for pipes, pumps and turbines. Dissolved compounds also tend to precipitate out of solution when these fluids are flashed into steam, clogging up the system.

Most geothermal power plants attempt to keep the working geothermal fluids within a closed system that returns them to the original reservoir after useful energy has been extracted. Despite this, many geothermal power plants release small amounts of these fluids into the surface environment. This is a result of having to vent steam that has reached excessive pressures, or mechanical breakdowns such as broken pipes. The major gaseous discharge from geothermal plants is hydrogen sulfide (H2S), which smells like rotten eggs and can be toxic or fatal at high concentrations. The release of acidic geothermal fluids into surface water is also a concern, as it can damage aquatic ecosystems or contaminate drinking water supplies. Finally, locations with potential geothermal resources have often become tourist destinations due to attractions like hot springs and geysers. Producing energy from these resources can eliminate these naturally occurring features, hurting tourism and altering natural processes.

Conclusions

Geothermal energy represents a potentially huge source of reliable heat and electricity. The technology exists to exploit this resource in an environmentally acceptable manner, although only a few sites are cost effective at the present time. The best geothermal resources are not evenly distributed around the world; but more costly sources of geothermal energy such as HDR are widely available. The amount of geothermal energy utilized in the future will depend upon the cost and environmental concerns associated with traditional sources of energy, rather than the limits of the geothermal resource. As supplies of fossil fuels dwindle, or the impacts of global warming and acid rain become more severe, geothermal energy will become an attractive option for supplying heat and electricity in the future.





BIOMASS ENERGY - Lanjutan HO 40

Introduction to biopowerBiopower, or biomass power, is the use of biomass to generate electricity. There are six major types of biopower systems:

(i) direct-fired (iv) anaerobic digestion

(ii) Co-firing (v) pyrolysis

(iii) gasification (vi) small, modular

Direct-fired Systems

Most of the biopower plants in the world use direct-fired systems. They burn bioenergy feedstocks directly to produce steam. This steam is usually captured by a turbine, and a generator then converts it into electricity.

In some industries, the steam from the power plant is also used for manufacturing processes or to heat buildings. These are known as combined heat and power facilities. For instance, wood waste is often used to produce both electricity and steam at paper mills.

Co-firing Systems

Many coal-fired power plants can use co-firing systems to significantly reduce emissions, especially sulfur dioxide emissions. Co-firing involves using bioenergy feedstocks as a supplementary energy source in high efficiency boilers.

Gasification Systems

Gasification systems use high temperatures and an oxygen-starved environment to convert biomass into a gas (a mixture of hydrogen, carbon monoxide, and methane).

The gas fuels what's called a gas turbine, which is very much like a jet engine, only it turns an electric generator instead of propelling a jet.

The decay of biomass produces a gas— methane— that can be used as an energy source. In landfills, wells can be drilled to release the methane from the decaying organic matter. Then pipes from each well carry the gas to a central point where it is filtered and cleaned before burning.

Anaerobic digestion.

Methane also can be produced from biomass through a process called anaerobic digestion. Anaerobic digestion involves using bacteria to decompose organic matter in the absence of oxygen.



BIOMASS ENERGY - Lanjutan HO 41

Methane can be used as an energy source in many ways. Most facilities burn it in a boiler to produce steam for electricity generation or for industrial processes.

Two new ways include the use of microturbines and fuel cells. Microturbines have outputs of 25 to 500 kilowatts. About the size of a refrigerator, they can be used where there are space limitations for power production. Methane can also be used as the "fuel" in a fuel cell. Fuel cells work much like batteries but never need recharging, producing electricity as long as there's fuel.

Pyrolysis

In addition to gas, liquid fuels can be produced from biomass through a process called pyrolysis. Pyrolysis occurs when biomass is heated in the absence of oxygen. The biomass then turns into a liquid called pyrolysis oil, which can be burned like petroleum to generate electricity. A biopower system that uses pyrolysis oil is being commercialized.

Small, Modular Systems

Several biopower technologies can be used in small, modular systems.

A small, modular system generates electricity at a capacity of 5 megawatts or less. This system is designed for use at the small town level or even at the consumer level.

For example, some farmers use the waste from their livestock to provide their farms with electricity. Not only do these systems provide renewable energy, they also help farmers and ranchers meet environmental regulations.

Small, modular systems also have potential as distributed energy resources. Distributed energy resources refer to a variety of small, modular power-generating technologies that can be combined to improve the operation of the electricity delivery system.



HYDROGEN ENERGY HO 42

Energy Density of Some Materials (KHW/kg)

Material Energy Density (KHW/kg)

Gasoline 14

Lead Acid Batteries 0.04

Hydro-storage 0.3 (per meter3)

Flywheel, Steel 0.05

Flywheel, Carbon Fibre 0.2

Flywheel, Fused Silica 0.9

Hydrogen 38

Compressed Air 2 (per meter3)

So potentially, Hydrogen wins big but the main problem is that there are no naturally occurring sources of hydrogen so it must be made and that has an energy cost associated with it.

Hydrogen as a Secondary Fuel:

While hydrogen is the most abundant element in the Universe on the Earth it is mostly found as water.

Hydrogen can be easily separated from Oxygen in water via Electrolysis. This process is about 67% efficient

Burning hydrogen combines with oxygen to form water --> no other combustion products (except for small amounts of nitrogen oxides formed around high temperature combustion zone)

For use as a secondary fuel, Hydrogen needs to be stored as a liquid. (20 K; -253 C).

As a liquid its energy density per unit volume is 1000 times higher.

For a given stored energy requirment, a cryogenic hydrogen facility is much less expensive than a pumped hydro facility

But overall efficiency is 25% cryogenic storage is energy intensive

But, one can make a hydgrogen-oxygen fuel cell Using a catalyst, hydrogen combines with oxygen to make water plus electricity. In the lab, such cells can acheive 85% efficiency but large scale value is unknown and untested although there have been some recent breakthroughs:


http://zebu.uoregon.edu/2001/ph162/images/earth3.gif

http://zebu.uoregon.edu/2001/ph162/images/15.jpg

http://solstice.crest.org/


HYDROGEN ENERGY - Lanjutan HO 43

Hydrogen Fuel Cells

Notes:

To produce power in large amounts, many of these cells are combined into a fuel cell stack.

There will be some electron loss depending on the work done so the process is not 100% efficient as the animation shows.

Until recently, a fuel cell stack was difficult and expensive to build.

Basic Chemistry of a Fuel Cell:

Anode: 2H2 --> 4H+ + 4e-

Cathode: 4e- + 4H+ + O2 --> 2H2O

Overall: 2H2 + O2 --> 2H2O




What about fuel cell yield? This information is hard to find, but General Motore (USA) announced in October 2001 the following specifications:

Rated Output: 1.75 KWH per Litre of Hydrogen (this would cost about 25 cents at current KWH prices)

Fuel Cell Stack weighs 180 pounds and gives continuous output of 100 KW to scale things, your home requires about 2KW of power or therefore 4.5 pounds of Hydrogen full cell stack.

Production of Hydrogen

Hydrogen is already produced mainly to form ammonia to be used in fertilizer. Hydrogen is extracted from methane and steam to make Carbon Dioxide.

Ammonia = NH3

Methane = CH4

Carbon Dioxide = CO2

Water = H20

Problems with the use of Hydrogen:

For 10% of our national energy budget, 400 1000 Megawatt power plants operating at 24 hours per day would be required to produce hydrogen via electrolysis. This is twice the current national demand.

Hydrogen is very explosive when mixed with oxygen. In its pure state, it poses no explosive threat so is perfectly safe to ship in pipelines. Can explode when mixed with air at concentrations of 4-75%. The ignition energy for this mixture is also very small and easily generated from a spark of static electricity (Hindenburg Disaster).

Transport of Hydrogen Gas:

Use existing natural gas pipelines

For a given energy requirement, 3 times as much hydrogen is needed as natural gas

But hydrogen has lower density and can be pumped at 3 times the flow rate of natural gas.

Pipeline systems are very efficient compared to transmission losses over long electrical grids




Costs/Problems:

Because of the inefficiency in producing it, hydrogen will always be more expensive than the electricity that produced it, if you do the price comparison at the production site

But, for situations where customers are 1000 miles away from the production site - it is cheaper to deliver hydrogen through a pipeline system than electricity through the power grid.

For example, a possible strategy is to build large, sturdy windmills in the Aleutian Island Chain (one of the windiest places on the Earth), for the purposes of producing electricity to make hydrogen from Sea Water. The hydrogen would then be shipped over the pipeline network to customers thousands of miles away.

The use of liquid hydrogen as a fuel source has potential (particularly on jet airplanes) but technical problems associated with storage and delivery have not yet been overcome

Best hope Hydrogen fuel cell technology will continue to improve and soon (3-5 years) individual vehicles will use this as a main fuel source.

However, it is quite unlikely that we will ever see electric production from hydrogen as the economics of the efficiency cycle is against this.



NUCLEAR ENERGY HO 46

Nuclear Power

Most power plants produce electricity by first boiling water to produce steam. The steam is used to spin a turbine. The shaft of the turbine spins the generator (a large coil of wire) between two magnets. The spinning coil of wire generates electricity. The main difference between a nuclear power plant and other kinds of power plants lies in the way the water is heated to steam. In a nuclear power plant, heat is produced by splitting atoms, rather than, for example, the combustion of oil, gas, or coal in a, respectively, oil-, gas-, or coal-fired plant.

How Nuclear Power Works

Nuclear power plants provide about 17 percent of the world's electricity. Some countries depend more on nuclear power for electricity than others. In France, for instance, about 75 percent of the electricity is generated from nuclear power, according to the International Atomic Energy Agency. In the United States, nuclear power supplies about 15 percent of the electricity overall, but some states get more power from nuclear plants than others. There are more than 400 nuclear power plants around the world, with more than 100 in the United States.


http://science.howstuffworks.com/framed.htm?parent=nuclear-power.htm&url=http://www.iaea.org/worldatom

http://science.howstuffworks.com/framed.htm?parent=nuclear-power.htm&url=http://www.iaea.org/worldatom


NUCLEAR ENERGY - Lanjutan HO 47

Nuclear Fission

Uranium is a fairly common element on Earth, incorporated into the planet during the planet's formation. Uranium is originally formed in stars. Old stars exploded, and the dust from these shattered stars aggregated together to form our planet. Uranium-238 (U-238) has an extremely long half-life> (4.5 billion years), and therefore is still present in fairly large quantities. U-238 makes up 99 percent of the uranium on the planet. U-235 makes up about 0.7 percent of the remaining uranium found naturally, while U-234 is even rarer and is formed by the decay of U-238. (Uranium-238 goes through many stages or alpha and beta decay to form a stable isotope of lead, and U-234 is one link in that chain.)

Uranium-235 has an interesting property that makes it useful for both nuclear power production and for nuclear bomb production. U-235 decays naturally, just as U-238 does, by alpha radiation. U-235 also undergoes spontaneous fission a small percentage of the time. However, U-235 is one of the few materials that can undergo induced fission. If a free neutron runs into a U-235 nucleus, the nucleus will absorb the neutron without hesitation, become unstable and split immediately. See How Nuclear Radiation Works for complete details.

The animation above shows a uranium-235 nucleus with a neutron approaching from the top. As soon as the nucleus captures the neutron, it splits into two lighter atoms and throws off two or three new neutrons (the number of ejected neutrons depends on how the U-235 atom happens to split). The two new atoms then emit gamma radiation as they settle into their new states. There are three things about this induced fission process that make it especially interesting:

The probability of a U-235 atom capturing a neutron as it passes by is fairly high. In a reactor working properly (known as the critical state), one neutron ejected from each fission causes another fission to occur. The process of capturing the neutron and splitting happens very quickly, on the order of picoseconds (1x10-12 seconds).

An incredible amount of energy is released, in the form of heat and gamma radiation, when a single atom splits. The two atoms that result from the fission later release beta radiation and gamma radiation of their own as well. The energy released by a single fission comes from the fact that the fission products and the neutrons, together, weigh less than the original U-235 atom. The difference in weight is converted directly to energy at a rate governed by the equation E = mc2.


http://science.howstuffworks.com/atom.htm

http://science.howstuffworks.com/nuclear.htm

http://science.howstuffworks.com/nuclear-bomb.htm

http://science.howstuffworks.com/framed.htm?parent=nuclear-power.htm&url=http://dictionary.reference.com/search?q=%20isotope

http://science.howstuffworks.com/nuclear2.htm

http://science.howstuffworks.com/nuclear2.htm

http://science.howstuffworks.com/star.htm



Something on the order of 200 MeV (million electron volts) is released by the decay of one U-235 atom (if you would like to convert that into something useful, consider that 1 eV is equal to 1.602 x 10-12 ergs, 1 x 107 ergs is equal to 1 joule, 1 joule equals 1 watt-second, and 1 BTU equals 1,055 joules). That may not seem like much, but there are a lot of uranium atoms in a pound of uranium. So many, in fact, that a pound of highly enriched uranium as used to power a nuclear submarine or nuclear aircraft carrier is equal to something on the order of a million gallons of gasoline. When you consider that a pound of uranium is smaller than a baseball, and a million gallons of gasoline would fill a cube 15 metres per side (15 metres is as tall as a five-story building), you can get an idea of the amount of energy available in just a little bit of U-235.

In order for these properties of U-235 to work, a sample of uranium must be enriched so that it contains 2 percent to 3 percent or more of uranium-235. Three-percent enrichment is sufficient for use in a civilian nuclear reactor used for power generation. Weapons-grade uranium is composed of 90-percent or more U-235.

Inside a Nuclear Power Plant

To build a nuclear reactor, what you need is some mildly enriched uranium. Typically, the uranium is formed into pellets with approximately the same diameter as a dime and a length of an inch or so. The pellets are arranged into long rods, and the rods are collected together into bundles. The bundles are then typically submerged in water inside a pressure vessel. The water acts as a coolant. In order for the reactor to work, the bundle, submerged in water, must be slightly supercritical. That means that left to its own devices, the uranium would eventually overheat and melt.

To prevent this, control rods made of a material that absorbs neutrons are inserted into the bundle using a mechanism that can raise or lower the control rods. Raising and lowering the control rods allow operators to control the rate of the nuclear reaction. When an operator wants the uranium core to produce more heat, the rods are raised out of the uranium bundle. To create less heat, the rods are lowered into the uranium bundle. The rods can also be lowered completely into the uranium bundle to shut the reactor down in the case of an accident or to change the fuel.

The uranium bundle acts as an extremely high-energy source of heat. It heats the water and turns it to steam. The steam drives a steam turbine, which spins a generator to produce power. In some reactors, the steam from the reactor goes through a secondary, intermediate heat exchanger to convert another loop of water to steam, which drives the turbine. The advantage to this design is that the radioactive water/steam never contacts the turbine. Also, in some reactors, the coolant fluid in contact with the reactor core is gas (carbon dioxide) or liquid metal (sodium, potassium); these types of reactors allow the core to be operated at higher temperatures. Once you get past the reactor itself, there is very little difference between a nuclear power plant and a coal-fired or oil-fired power plant except for the source of the heat used to create steam.


http://science.howstuffworks.com/gasoline.htm

http://science.howstuffworks.com/aircraft-carrier.htm

http://science.howstuffworks.com/submarine.htm

http://science.howstuffworks.com/question501.htm



The reactor's pressure vessel is typically housed inside a concrete liner that acts as a radiation shield. That liner is housed within a much larger steel containment vessel. This vessel contains the reactor core as well the hardware (cranes, etc.) that allows workers at the plant to refuel and maintain the reactor. The steel containment vessel is intended to prevent leakage of any radioactive gases or fluids from the plant.

Finally, the containment vessel is protected by an outer concrete building that is strong enough to survive such things as crashing jet airliners. These secondary containment structures are necessary to prevent the escape of radiation/radioactive steam in the event of an accident like the one at Three Mile Island. The absence of secondary containment structures in Russian nuclear power plants allowed radioactive material to escape in an accident at Chernobyl.

Uranium-235 is not the only possible fuel for a power plant. Another fissionable material is plutonium-239. Plutonium-239 can be created easily by bombarding U-238 with neutrons -- something that happens all the time in a nuclear reactor.

Subcriticality, Criticality and Supercriticality

When a U-235 atom splits, it gives off two or three neutrons (depending on the way the atom splits). If there are no other U-235 atoms in the area, then those free neutrons fly off into space as neutron rays. If the U-235 atom is part of a mass of uranium -- so there are other U-235 atoms nearby -- then one of three things happens:

If, on average, exactly one of the free neutrons from each fission hits another U-235 nucleus and causes it to split, then the mass of uranium is said to be critical. The mass will exist at a stable temperature. A nuclear reactor must be maintained in a critical state.

If, on average, less than one of the free neutrons hits another U-235 atom, then the mass is subcritical. Eventually, induced fission will end in the mass.

If, on average, more than one of the free neutrons hits another U-235 atom, then the mass is supercritical. It will heat up.

For a nuclear bomb, the bomb's designer wants the mass of uranium to be very supercritical so that all of the U-235 atoms in the mass split in a microsecond. In a nuclear reactor, the reactor core needs to be slightly supercritical so that plant operators can raise and lower the temperature of the reactor. The control rods give the operators a way to absorb free neutrons so the reactor can be maintained at a critical level.

The amount of uranium-235 in the mass (the level of enrichment) and the shape of the mass control the criticality of the sample. You can imagine that if the shape of the mass is a very thin sheet, most of the free neutrons will fly off into space rather than hitting other U-235 atoms. A sphere is the optimal shape. The amount of uranium-235 that you must collect together in a sphere to get a critical reaction is about 2 pounds (0.9 kg). This amount is therefore referred to as the critical mass. For plutonium-239, the critical mass is about 10 ounces (283 grams).


http://science.howstuffworks.com/nuclear-bomb.htm

http://science.howstuffworks.com/framed.htm?parent=nuclear-power.htm&url=http://www.chernobyl.co.uk/

http://science.howstuffworks.com/framed.htm?parent=nuclear-power.htm&url=http://www.pbs.org/wgbh/amex/three/

http://science.howstuffworks.com/nuclear.htm



What Can Go Wrong

Well-constructed nuclear power plants have an important advantage when it comes to electrical power generation -- they are extremely clean. Compared with a coal-fired power plant, nuclear power plants are a dream come true from an environmental standpoint. A coal-fired power plant actually releases more radioactivity into the atmosphere than a properly functioning nuclear power plant. Coal-fired plants also release tons of carbon, sulfur and other elements into the atmosphere (see this page for details).

Unfortunately, there are significant problems with nuclear power plants:

Mining and purifying uranium has not, historically, been a very clean process.

Improperly functioning nuclear power plants can create big problems. The Chernobyl disaster is a good recent example. Chernobyl was poorly designed and improperly operated, but it dramatically shows the worst-case scenario. Chernobyl scattered tons of radioactive dust into the atmosphere.

Spent fuel from nuclear power plants is toxic for centuries, and, as yet, there is no safe, permanent storage facility for it.

Transporting nuclear fuel to and from plants poses some risk, although to date, the safety record in the United States has been good.

These problems have largely derailed the creation of new nuclear power plants in the those countries which use nuclear power. Society seems to have decided that the risks outweigh the rewards.


http://science.howstuffworks.com/framed.htm?parent=nuclear-power.htm&url=http://www.chernobyl.co.uk/

http://science.howstuffworks.com/question481.htm

Bab 4 Strategi Penyajian Tugas

Tugas

Tugas 1

The Light Bulb Intelligence Test

Saving the Earth via choice of light bulb

A 15-Watt fluorescent fixture produces as much light as a 75-Watt incandescent bulb.

The fluorescent bulb lasts for 10,000 hours

The incandescent bulb lasts for 1000 hours

The fluorescent bulb costs 50,000 Rp. (which is why no one buys them)

The incandescent bulb costs 5,000 Rp. (which is why everyone buys them)

Now lets calculate the total cost over the lifetime of the fluorescent bulb assuming a cost rate of 500 Rp per KWH.

Fluorescent bulb = 10,000 hours * 15 Watts = 150 KWH * 500 Rp. per KWH = 75,000 Rp. + the cost of the bulb. Therefore total cost = 125,000Rp.

Incandescent bulb = 1,000 hours * 75 Watts = 75 KWH * 500 Rp. per KWH = 32,500 Rp. + the cost of the bulb. Therefore total cost = 37,500 Rp.

Now multiply this by 10 = 375,000 Rp.

So, over a 10,000 hour period, the fluorescent bulb has a total cost of 125,000 and the incandescents have a total cost of 375,000 Rp.

You just saved 250,000 Rp. as well as 600 KWH of energy.

Clearly always use fluorescent bulbs if you are interested in saving energy and money.

However, this requires thinking on the long term!

Tugas 2

Solar Powered Lamps

1. Require Circuit

2. Materials

Tugas 3

Example Wind Problem:

In your back yard the average wind speed is 10 mph which yields 100 watts per square meter. If the wind blows 40 mph, how much power does a wind mill of 2 square meters generate?


http://zebu.uoregon.edu/2000/es202/lightbulb.html


1. 40/10 = 4 wind blows 4 times harder

2. 43 = 64 if a 10 mph wind gives you 100 watts per square meter then a 40 mph wind gives you 64 times more power per square meter 6400 watts per square meter

3. total power = 6400 watts per square meter * 2 square meters = 12800 watts = 12.8 Kilowatts this is a lot!

The above calculation is known as a scaling calculation; you simply need to scale the original

conditions to the final conditions. You only need to know the v3 to do this.

1. Siapa saja yang melakukan pengawasan terhadap undang-undang keselamatan kerja dan sejauh mana kewenangan masing-masing. Diskusikan tentang susunan dan tugas Panitia Banding.

2. Apa saja kewajiban pembinaan pengurus terhadap tenaga kerja baru. Diskusikan tugas

pembinaan lainnya dari pengurus.

3. Sebutkan fungsi Panitia K3, dan diskusikan susunan kepanitiaan K3 yang sebaiknya.

Tugas 4

Kewajiban dan Hak Tenaga Kerja serta Pengurus

Petunjuk :

1. Diskusikan kewajiban dan hak tenaga kerja menurut undang-undang Keselamatan Kerja.

2. Sebutkan kewajiban pengurus terhadap dokumen undang-undang Keselamatan Kerja dan

peraturan pelaksanaannya, terhadap gambar keselamatan kerja dan alat perlindungan diri

untuk tenaga kerja.

Tugas 5

Tata cara Pelaporan dan Pemeriksaan Kecelakaan

Petunjuk :

1. Jelaskan tata cara pelaporan suatu kecelakaan kerja. Diskusikan dengan grup belajar anda

tentang format laporan dan pengisiannya.

2. Sebutkan prosedur pemeriksaan kecelakaan dan jenis pemeriksaan yang dilakukan.

Diskusikan juga format-format laporan pemeriksaan.



Tugas 6

Penerapan dan Audit Sistem Manajemen K3

Petunjuk :

3. Jelaskan ketentuan-ketentuan yang wajib dilakukan oleh perusahaan dalam penerapan

Sistem Manajemen K3. Diskusikan dengan grup belajar anda.

4. Sebutkan unsur-unsur audit Sistem Manajemen K3 dan diskusikan mekanisme

pelaksanaan audit.


Bab 4 Strategi Penyajian Transparansi

OHT 1

Transparansi


Bab 4 Strategi Penyajian Transparansi

OHT 2


Bab 5 Cara Menilai Unit Ini

BAB 5 CARA MENILAI UNIT INI

Apa yang Dimaksud dengan Penilaian ?

Penilaian adalah proses pengumpulan bukti-bukti hasil ujian/pekerjaan dan pemberian nilai atas kemajuan peserta pelatihan dalam mencapai kriteria unjuk kerja seperti yang dimaksud dalam Standar Kompetensi. Bila pada nilai yang ditetapkan telah tercapai ( sesuai dengan kriteria ), maka dinyatakan bahwa kompetensi sudah dicapai . Penilaian lebih untuk mengidentifikasi pencapaian dan penguasaan kompetensi peserta pelatihan dari pada hanya untuk membandingkan prestasi peserta terhadap peserta lain.

Apa yang Dimaksud dengan Kompeten?

Tanyakan pada diri Anda sendiri : “Kemampuan kerja apa yang benar-benar dibutuhkan oleh peserta pelatihan”?

Jawaban terhadap pertanyaan ini akan mengatakan kepada Anda tentang apa yang kita maksud dengan kata “kompeten”. Untuk menjadi kompeten dalam suatu pekerjaan yang berkaitan dengan keterampilan berarti bahwa orang tersebut harus mampu untuk :

menampilkan keterampilan pada level (tingkat) yang dapat diterima

mengorganisasikan tugas-tugas yang dibutuhkan.

merespon dan bereaksi secara layak bila sesuatu salah

memenuhi suatu peranan dalam sesuatu rangkaian tugas-tugas pada pekerjaan

mentransfer/mengimplementasikan keterampilan dan pengetahuan pada situasi baru.

Bila Anda menilai kompetensi ini Anda harus mempertimbangkan seluruh issue di atas untuk mencerminkan sifat kerja yang nyata .

Pengakuan Kompetensi yang Dimiliki

Prinsip penilaian terpadu memberikan pengakuan terhadap kompetensi yang ada tanpa memandang dari mana kompetensi tersebut diperoleh. Penilai mengakui bahwa individu-individu dapat mencapai kompetensi dalam berbagai cara:

kualifikasi terdahulu

belajar secara informal.

Pengakuan terhadap kompetensi yang ada dengan mengumpulkan bukti-bukti kemampuan untuk dinilai apakah seseorang telah memenuhi standar kompetensi, baik memenuhi standar kompetensi untuk suatu pekerjaan maupun untuk kualifikasi formal.

Kualifikasi Penilai

Dalam kondisi Iingkungan kerja, seorang peniIai industri yang diakui akan menentukan apakah seorang pekerja mampu melakukan tugas yang terdapat dalam unit kompetensi ini . Untuk menilai unit ini mungkin Anda akan memilih metode yang ditawarkan dalam pedoman ini, atau mengembangkan metode Anda sendiri untuk melakukan penilaian. Para penilai harus memperhatikan petunjuk penilaian dalam standar kompetensi sebelum memutuskan metode penilaian yang akan dipakai.



Ujian yang Disarankan

Umum

Unit Kompetensi ini, secara umum mengikuti format berikut:

(a) Menampilkan pokok keterampilan dan pengetahuan untuk setiap sub-kompetensi/kriteria unjuk kerja.

(b) Berhubungan dengan sesi praktik atau tugas untuk memperkuat teori atau mempersiapkan praktik dalam suatu keterampilan.

Hal ini penting sekali, di mana peserta dinilai (penilaian formatif) pada setiap elemen kompetensi. Mereka tidak boleh melanjutkan unit berikutnya sebelum mereka benar-benar menguasai (kompeten) pada materi yang sedang dilatihkan .

Sebagai patokan disini seharusnya paling sedikit satu penilaian tugas untuk pengetahuan pokok pada setiap elemen kompetensi. Setiap sesi praktik atau tugas seharusnya dinilai secara individu untuk tiap Sub-Kompetensi. Sesi praktik seharusnya diulang sampai tingkat penguasaan yang disyaratkan dari sub kompetansi dicapai.

Tes pengetahuan pokok biasanya digunakan tes obyektif. Sebagai contoh, pilihan ganda, komparasi, mengisi/melengkapi kalimat. Tes essay dapat juga digunakan dengan soal-soal atau pertanyaan yang relevan dengan unit ini.

Penilaian untuk unit ini, berdasar pada dua hal yaitu:

pengetahuan dan keterampilan pokok

hubungan dengan keterampilan praktik.

Untuk penilaian unit “Keselamatan dan Kesehatan Kerja “ disarankan hal-hal sebagai berikut:

Penilaian Pengetahuan Pokok

Penilaian Teori

Sub-Kompetensi/Elemen 1 : Peraturan Kerja

Tes berdasarkan pada soal-soal berikut :

Jawablah pertanyaan-pertanyaan berikut berdasarkan pilhan yang tepat !

Pertanyaan 1 sampai 5, lingkari salah satu BETUL atau SALAH

1. Pengertian tempat kerja dalam undang-undang keselamatan kerja adalah tiap ruangan atau lapangan, tertutup atau terbuka, bergerak atau tetap, dimana tenaga kerja melakukan pekerjaan.

BETUL SALAH

2. Ruang lingkup yang dicakup oleh undang-undang no 1 tahun 1970 tentang keselamatan kerja adalah mengatur pekerja Indonesia, walaupun bekerja di negara lain.

BETUL SALAH



3. Kewajiban melaporkan tiap kecelakaan yang terjadi di tempat kerja oleh pengurus atau pengusaha meliputi yang telah dan yang belum mengikutsertakan pekerjaannya ke dalam program jaminan sosial tenaga kerja.

BETUL SALAH

4. Pemeriksaan dan pengkajian kecelakaan dilakukan oleh pegawai pengawas setelah

Kepala Kantor Departemen Tenaga Kerja menerima laporan kecelakaan dari pengurus

atau pengusaha.

BETUL SALAH

5. Sistem Manajemen K3 wajib diterapkan oleh perusahaan yang proses atau bahan

produksinya mengandung potensi bahaya peledakan, kebakaran, pencemaran dan

penyakit akibat kerja, walaupun tenaga kerjanya dibawah batas ketentuan (kurang dari

serratus orang).

BETUL SALAH

Berikan tanda cek ( V ) pada kotak dekat jawaban yang terbaik.

6. Untuk pembuktian penerapan Sistem Manajemen K3, perusahaan dapat melakukan audit melalui Badan Audit yang ditunjuk oleh :

(a) Pengusaha.

(b) Pengawas.

(c) Menteri

Sub-Kompetensi/Elemen 2 : Bahaya di tempat kerja



Pertanyaan 1 sampai 5, lingkari salah satu BETUL atau SALAH.

1. Pekerja seharusnya menyadari bahaya ditempat kerja.

BETUL SALAH

2. Bahaya dapat mengarah pada kecelakaan, cedera atau sakit

BETUL SALAH

3. Semua bahaya tempat kerja dapat dihilangkan.

BETUL SALAH



4. Pekerja yang telah minum alkohol atau sedang melakukan pengobatan dapat mencederai

diri sendiri atau orang lain.

BETUL SALAH

5. Berlebihan panas atau dingin, kesengat listrik dan ketinggian juga berbahaya.

BETUL SALAH

Sub-Kompetensi/Elemen 3 : Tata Laksana Indusri




1. Bahan yang mudah terbakar mudah dimakan api

BETUL SALAH

2. Jalan masuk seharusnya dengan jelas ditandai dengan garis hijau.

BETUL SALAH

3. Simbol keselamatan segi-tiga 'tengkorak dan tulang bersilang' digambar diatas latar

belakang kuning, peringatan bahaya biologi.

BETUL SALAH

4. Lingkaran biru indikasi simbol keselamatan dimana peralatan pelindung harus dipakai.

BETUL SALAH

5. Tata laksana industri adalah tanggung jawab dari staf kebersihan.

BETUL SALAH


6. Saluran tenaga listrik seharusnya tidak terhampar melintang dipermukaan lembab/basah

sebab :

(a) Bisa tersengat listrik.

(b) Sekering/pengaman bisa putus.

(c) Menambah beban listrik yang digunakan.



Sub-Kompetensi/Elemen 4 : Polusi pada Indusri




1. Dengan debu dan serat di udara cukup aman bekerja.

BETUL SALAH

2. Semua bahaya bahan kimia dengan mudah identifikasi.

BETUL SALAH

3. Ketika membuang sisa/sampah bahan kimia, harus dikontrol sebagaimana mestinya.

BETUL SALAH

4. Kebisingan keras yang terus menerus dapat menyebabkan kehilangan pendengaran.

BETUL SALAH

5. Polusi di pabrik kita dapat dikontrol atau dicegah.

BETUL SALAH

Sub-Kompetensi/Elemen 5 : Keselamatan Pribadi




1. Anda seharusnya selalu memikirkan tentang apa yang dapat terjadi sebelum anda melakukan sesuatu.

BETUL SALAH

2. Pekerja seharusnya dengan benar dilatih menggunakan dan merawat pakaian dan perlengkapan keselamatan.

BETUL SALAH

3. Kenyamanan pekerja menggunakan pakaian dan perlengkapan keselamatan tidak penting.

BETUL SALAH

4. Pemadam kebakaran karbon dioksida cocok untuk kebakaran kelistrikan.

BETUL SALAH



5. Sesuatu yang pertama dilakukan dalam kasus kebakaran adalah memberitahu pasukan pemadam kebakaran.

BETUL SALAH


6. Kaca-mata dan kaca pelindung keselamatan lainnya mungkin disediakan untuk melindungi dari :

(a) Pecahan beterbangan.

(b) Bahaya bahan kimia.

(c) Cahaya yang hebat/tajam (yaitu dalam pengelasan).

(d) Semua hal diatas.



Ringkasan Penilaian Pengetahuan dan Keterampilan

Gunakan tugas-tugas ini untuk menetapkan apakah peserta pelatihan telah menguasai pokok-pokok pengetahuan dan keterampilan yang diperlukan.

Pokok-pokok Pengetahuan dan

Keterampilan

Tugas-tugas PenilaianYa Tidak

Perlu Latihan

Lanjutan

1.0 Mengidentifikasi undang-undang dan peratuan tentang keselamatan dan kesehatan kerja (K3).




2.0 Mengidentifikasi bahaya di tempat kerja.

2.1 Potensi bahaya di tempat diidentifkasi.

2.2 Beberapa cara untuk mengontrol dan mencegah bahaya diuraikan.

3.0 Menjelaskan tata laksana industri.



4.0 Menjelaskan polusi pada industri.



5.0 Menjelaskan keselamatan pribadi.







Checklist yang Disarankan Bagi Penilai

Modul : Keselamatan dan Kesehatan Kerja.

Nama Peserta : Nama Penilai :

Apakah telah memberikan bukti-bukti yang cukup yang menunjukkan bahwa peserta dapat : Catatan

Menjelaskan isi Undang-undang dan peraturan tentang Keselamatan dan Kesehatan Kerja (K3) meliputi :

- Syarat-syarat keselamatan kerja

- Pengawasan dan Pembinaan keselamatan dan kesehatan kerja

- Hak dan kewajian tenaga kerja dan pengurus.

- Tata cara pelaporan kecelakaan

- Pemeriksaan kecelakaan

- Tujuan, sasaran dan penerapan sistem manajemen K3

- Audit sistem manajemen K3 dan mekanisme pelaksanaan audit

….

….

….

….

….

….

….

Mengidentifikasi potensi dan mengatasi bahaya di tempat kerja :

- Jenis-jenis bahaya

- Pencegahan dan pengontrolan bahaya.

….

….

Menjelaskan cara tata laksana industri, diantaranya :

- Tata laksana yang baik

- Penyimpanan bahan

- Gambar simbol keselamatan kerja.

….

….

….

Menjelaskan sumber dan pengontrolan polusi pada industri :

- Polusi serat dan debu serta pencegahan

- Polusi bahan kimia serta pencegahan.

- Polusi kebisingan serta pencegahan

….

….

….

Menjelaskan penyebab cedera dan prosedur keselamatan pribadi yakni :

- Tindakan keamanan kerja

- Perlengkapan dan pakaian pelindung serta program ditempat kerja

- Keselamatan dan perlindungan kebakaran

- Prosedur pengungsian darurat

- Pertolongan pertama pada kecelakaan.

….

….

….

….

….



Lembar Penilaian

Unit : Alternative Energy Sources

Nama Peserta Pelatihan : ……………………………………

Nama Penilai : ………….………………..……….

Peserta yang Dinilai : Kompeten

Kompetensi yang Dicapai

Umpan balik untuk Peserta:

Tanda tangan

Peserta sudah diberitahu tentang hasil penilaian dan alasan-ala

san mengambil keputusan

Tanda tangan Penilai:

Tanggal:

Saya sudah diberitahu tentang hasil penilaian dan alasan mengambil keputusan tersebut.

Tanda tangan Peserta Pelatihan:

Tanggal:


package for alternative energy sources-250803

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