Renewable and Non-renewable Energies

Prepared by: Ms. Llupo

Non-Renewable vs. Renewable

• Non-renewable – resources that cannot regenerate quickly, takes thousands or millions of years.

• Renewable – resources that regenerate quickly within decades.

Energy Efficiency and Energy ConservationEnergy efficiency – the amount of useful energy produced compared to

the amount wasted as heat (2nd Law of Thermodynamics); built into the device or system, unavoidable waste

Examples of levels of energy efficiency:human body:

20-25%incandescent light bulb:

5%internal combustion engine:

20-25%steam turbine:

45%

Energy conservation – the effort to reduce the amount of energy used, some waste can be avoided

Energy Efficiency and Energy Conservation Map

Energy conservation and energy efficiency are presently the most powerful tools in transition to a clean energy future. As shown in the Energy Pyramid, renewable energy is an important piece of our future energy, but the largest opportunities are currently in energy conservation and efficiency.

Where does the electricity come from?

Renewables

•Wind •Solar•Hydropower•Geothermal •Tidal•Biomass

•Wave

Non- renewables • Fossil fuels Coal Natural gas Oil • Nuclear reaction

Wind Power

Advantages •No fossil fuels are generated•Take up less space than the average power station. Windmills only have to occupy a few square meters for the base, this allows the land around the turbine to be used for many purposes, for example agriculture.•Extraction of wind energy is much more efficient. The wind is free•Represents a great energy source when combined with solar panels•45%–55% efficiency

Disadvantages: • Less electricity than the average fossil fuels• Construction can be very expensive and costly too

Rotating blades are a danger to birds• Wind turbines can spoil the view and the rotating blades

are noisy• It is unreliable, since wind speed can change at any time

Solar Power Disadvantages: •Electricity cannot be produced when the Sun is not shining•Solar cells are only about 33 percent efficient.

Solar Power The four technologies employed to make use of solar energy are:•Daylighting•Passive Solar Heating•Active Solar Heating•Concentrating Solar Thermal•Photovoltaic(PV)

Solar Technologies• Daylighting• Passive Solar Heating

• Active Solar Heating

• Concentrating Solar Thermal

• Photovoltaics (PV)

Daylighting: the use of natural sunlight to brighten the building’s interior.

Passive Solar Heating: takes advantage of Sun’s warmth and materials that absorb that warmth during the day/release it at night when heat is needed.

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Flat Plate Collector

Evacuated Tube Collector

Active Solar Heating: solar collectors concentrate the sun’s power on dark color plates that absorb heat. Air or liquid flows through tubes and warmed by the plates.

Concentrating Solar Thermal: mirrors direct sunlight on one point. Water is turned into steam with this heat. The steam turns a turbine to create electricity.

Photovoltaic(PV): converts sunlight directly to electricity.

Hydro Power Advantages •There are no combustion emissions

•Operating costs are low and it is about 90% efficient

•95% efficiency

Disadvantages: •Flooding - large areas of land are flooded to create dams and reservoirs.

•Consequent impacts on people, animals and vegetation. When submerged vegetation decays, it produces methane and releases mercury.

•Impact stream flow

•Traps sediments and nutrients

•Decreases dissolved oxygen in water

Geothermal Power Advantages

•Less costs •Consumes less electricity •More efficiency than gas and oil furnaces •A highly acceptable solution as greenhouse gases and air pollutants levels are less •Cools and operates quietly•15%–20% efficiency

Disadvantages •High installation costs •Requires lots of space•Needs a bedrock base •Installation is tricky

Tidal Power Tidal energy is hydropower which converts the energy of tides into electricity or other forms of power. Tides are more predictable than wind energy and solar power.

Advantages • More predictable than wind energy and solar

power• Doesn’t depend on whether• No pollution • Requires no fuel• Not expensive to maintain • 95% efficiency

Disadvantages• A barrage is expensive to build and affects a wide

area • Environment is being affected • Provide power for only 10 hours a day• Cannot be installed everywhere

Biomass Power Advantages: •Using plant matter before it decomposes prevents•the release of methane gas•5% efficiency

Disadvantages: • Burning plant matter adds carbon dioxide to the

atmosphere• A large supply of biomass

fuels is not readily available

Fossil Fuels: Oil, Natural Gas, Coal• Fossil fuels originated from the decay of living

organisms millions of years ago

• 40% efficiency

Advantage: Oil is used in many areas such as

Advantages • Ample supply for 35-84 years • Low cost • High net energy yield • Easily transported within and between countries

Disadvantages • Artificially low price encourages waste and

discourages search for alternatives • Air pollution, releases CO2 when burned

• Moderate water pollution

Natural Gas – another fossil fuel

Mixture of gases•50–90% Methane (CH4)

•Ethane (C2H6)

•Propane (C3H8)

•Butane (C4H10)

•Hydrogen sulfide (H2S)

The use of Natural Gas• Produce electricity

• Heat homes - inside homes, water heater

• Industry - heat for warmth and producing things

• Vehicles

• Cooking

Advantages• High net energy yield • Low cost • Less air pollution than other fossil fuels • Lower CO2 emission than other fossil fuels

• Moderate environmental impact • Good fuel for fuel cells and gas turbines

Disadvantages • Releases CO2 when burned

• Leaks of methane – GHG • Shipped across ocean as highly explosive • Sometimes burned off and wasted at low price• Fractioning can cause groundwater contamination and earthquakes

Fossil Fuel Power - Coal

Advantage: Coal is inexpensive

Coal Power Disadvantages: •High GHG Emissions - it produces carbon dioxide and other gases that contribute to acid rain.•Harmful extraction process •High water demand •Thermal discharge - the process is only 30 percent efficient. That is, about 70 percent of the energy produced is lost as heat before it reaches the consumer•Waste created

Acid Mine Drainage

Acid mine drainage comes mainly from abandoned coal mines and active mining.

Nuclear Power - Uranium

Advantages•There are no greenhouse gas emissions.•A small amount of nuclear fuel will produce a great amount of energy•20%–50% efficiency

Nuclear power meets more than 50 per cent of Ontario's electricity needs.

Energy Output by 2008

Ontario Power Generation owns and operates the Pickering and Darlington Nuclear Power Stations. The two stations have a combined generating capacity of about 6,600 megawatts.

Pickering Nuclear Power Stations is one of the world's largest nuclear generating facilities. Capacity: 3,100 MW

Darlington Nuclear Power Stations sits on the shores of Lake Ontario, roughly 60-kilometres east of Toronto.Capacity: 3,500 MW

Disadvantages • Thermal Discharge - when cooling water is

discharged into the lake, the temperature of water rises.

• Radioactive Waste - power plants are very expensive and radioactive waste must be properly stored.

Three Mile IslandThree Mile Island• March 29, 1979, a reactor near Harrisburg, plant in Pennsylvania,

lost coolant water because of mechanical and human errors and suffered a partial meltdown

• 50,000 people evacuated & another 50,000 fled area

• Unknown amounts of radioactive materials released

• Partial cleanup & damages cost $1.2 billion

• Released radiation increased cancer rates.

ChernobylChernobyl

• April 26, 1986, reactor explosion, Ukraine flung radioactive debris into atmosphere

• Health ministry reported 3,576 deaths

• Green Peace estimates 32,000 deaths

• About 400,000 people were forced to leave their homes

• ~160,000 Km2 contaminated

• > Half million people exposed to dangerous levels of radioactivity, causing cancer, tumors, eye cataract, and genetic mutations

• Cost of incident > $358 billion

Effects of Chernobyl nuclear disaster

Fukushima disaster – Japan, March 2011Fukushima disaster – Japan, March 2011

Earthquake, followed by tsunami – subsequent loss of power to cool reactors, plus fire at plant

beforebefore

Dec 14 Classroom Electricity Audit

- 5 appliances - plug in a Wattmeter to measure the amount of energy it uses