Solar Gardens and Solar Energy

Kalamazoo Valley Museum ‐ Sunday Series: 11 March 2018Dr. Bradley J. Bazuin, 

Chair and Associate Professor,Electrical and Computer Engineering

Abstract• Solar energy collection and conversion to useful output power takes on 

many forms. All such systems are becoming less costly, easier to purchase and construct, and more visible in the community. The presentation will discuss: solar cells, panels and arrays; solar energy conversion from cell phone chargers to home solar arrays and solar gardens; and small‐scale classroom demonstration components that can be used for middle or high school hands‐on education. 

• Key Points– solar energy– solar cells, panels and arrays– solar energy system elements– small‐scale classroom demonstration components 

for middle or high school hands‐on education

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Support for the generation of this material was provided by a grant from Consumers Energy.

DisclaimerThis is a technical report generated by the author as a record of personal research and activity. Western Michigan University makes no representation that the material contained in this report is correct, error free or complete in any or all respects. Thus, Western Michigan University, it’s faculty, it’s administration, or students make no recommendation for the use of said material and take no responsibility for such usage. Therefore, persons or organizations who choose to use this material do so at their own risk.

Consumers Energy Solar Garden Projects web site,https://www.consumersenergy.com/residential/renewable-energy/solar-gardens

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Energy From the Sun• Solar Spectrum Irradiance

– Various models exist to describe available spectral energy. 

– The AM 1.5model is often used. – It represents an overall yearly 

average for mid‐latitudes solar collection and has been selected as a reference standard.

• Total Solar Power AM 1.5– A simple estimate of available 

power is … 

1000 W/m2 or  93 W/ft2 https://en.wikipedia.org/wiki/Solar_irradiance/

Wikipedia: Solar Irradiance

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US Irradiance

http://www.nrel.gov/gis/images/map_pv_national_hi-res_200.jpg

https://nsrdb.nrel.gov/ 5

Irradiation in Michigan• Annual average daily solar energy 

in watt‐hours per square meter per day– Kalamazoo ~ 3.9 kWh/m2/day

• Average MI Home Electricity Use: ~22.2 kWh/day– US avg. range: 17.5‐41.5 kWh/day– http://www.electricitylocal.com/states/michigan/

• Commercial PV Collection is currently from 5‐20% efficient– @ 20% ~ 0.78 kWh/m2/day

Photo credit: National Renewable Energy Laboratory and MSU Land Policy Institute, http://msue.anr.msu.edu/news/planning_and_zoning_for_solar_energy_readiness_a_hot_proposition_part_1 6

Sunlight Available• Projection effect

– The intensity of the sun directly overhead versus at an angle differs. Distance matters.

– Latitude, day of year, and time of day all matter.

• Atmospheric Losses– Energy is being absorbed and scattered the longer it is in earths 

atmosphere.– Distance light passes through atmosphere.

• Local weather – Cloud cover and moisture. More variations in absorption and 

scattering. 

http://www.pveducation.org/pvcdrom/properties-of-sunlight/solar-radiation-at-earths-surface

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Nominal 5 kW Array @ WMU

0.0001.0002.0003.0004.0005.0006.0007.0008.000

0100200300400500600700800

2017 Energy ProductionSuniva‐Solar Edge Array

Monthly kWh Cum MWh

0200400600800

010203040

January 2018Suniva‐Solar Edge Array

Daily kWh Month kWh

0200400600800

010203040

July 2017Suniva‐Solar Edge Array

Daily kWh Month kWh

Nearly 6 Mega-Watt Hours in 2017Maximum: 36 kWh in a dayAverage: 24-25 kWh in June & July

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Nominal 2.7 kW Array @ WMU

Over 3.3 Mega-Watt Hours in 2017Maximum: 20.8 kWh in a dayAverage: 12-15 kWh in June & July

0100200300400500

05

10152025

January 2018SMA‐Shingle Array

Daily kWh Monthly kWh

0100200300400500

05

10152025

7/1/20

177/3/20

177/5/20

177/7/20

177/9/20

177/11

/201

77/13

/201

77/15

/201

77/17

/201

77/19

/201

77/21

/201

77/23

/201

77/25

/201

77/27

/201

77/29

/201

77/31

/201

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July 2017SMA‐Shingle Array

Daily kWh Monthly kWh

0.0000.5001.0001.5002.0002.5003.0003.5004.0004.500

0.050.0

100.0150.0200.0250.0300.0350.0400.0450.0

2017 Energy ProductionSMA‐Shingle Array

Monthly kWh Cum MWh

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Reasons to Install PV• Offset energy bill

– return‐on‐investment must be justified• Off Grid Power

– access to utilities limited or not existent• Green Energy

– reduced carbon footprint, renewable energy, energy conservation, a life style choice

• Hobbyist or Experimenter– something different and interesting with potential benefits

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U.S. Solar Photovoltaic Cost

U.S. Solar Photovoltaic System Cost Benchmark: Q1 201, Ran Fu, David Feldman, Robert Margolis, Mike Woodhouse, and Kristen Ardani, National Renewable Energy Laboratory, Technical Report NREL/TP-6A20-68925 September 2017.

https://www.nrel.gov/docs/fy17osti/68925.pdf 11

Estimated Costs of Installation

Photovoltaic System Pricing Trends: Historical, Recent, and Near-Term Projections 2014 Edition, SunShot, US Department of Energy, D. Feldman, G. Narbose, et al., http://www.nrel.gov/docs/fy14osti/62558.pdf . 12

Solar Cells to PV‐System

By Rfassbind - Own work., Public Domain, https://commons.wikimedia.org/w/index.php?curid=34961018

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Collecting Solar Energy• Photovoltaic Cells (from Greek light‐volt)

– Made from semiconductor materials.

• Solar Cell Efficiency– Not all of the energy is collected by a PV device. – Based on the material types and wavelengths absorbed.– Different material combinations and designs have different efficiency.

• Silicon, Gallium‐Arsenide (GaAs), Copper Indium Gallium Diselenide(CIGS), and Organic and Polymer PV (OPV). 

• Performance of commercial and research PV tracked.– US National Renewable Energy Laboratory (NREL)

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PV Cell Types and Efficiency

National Renewable Energy Laboratory - National Center for Photovoltaicshttps://www.nrel.gov/pv/ 15

Conventional PV Curve• A maximum output power can be 

defined from the I‐V curve.– the point of maximum output 

power (MPP)– the power and MPP change as 

light levels change

• Impotent PV Cell Values– Voltage – open circuit (Voc)– Current – short circuit (Isc)– Voltage – MPP (Vmpp)– Current – MPP (Impp)

Cur

rent

Cur

rent

/Pow

er

Calculated Power

I-V vs. Light Intensity

Isc

Voc

Vmpp & Impp

PV Behavior

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Suniva Solar Cell Data Sheet

Suniva ARTisun® Select Data Sheets, SAMD_0044, Sept. 17 2013, Rev. 1 & April 25, 2013 17

Suniva Solar Panel

72 Series Connected Solar CellsVmpp 37.5-37.9 V, Impp 8.67-8.99 A

Suniva OPTIMUS® Solar Modules Data Sheets, SAMD_0051, Aug. 19, 2015, Rev. 6.

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“AC” Output Solar SystemGrid‐Tied or Net‐Metering

DC Voltage0 to 500 Vdc

AC Voltage @ 60 Hz110 Vac 2-phase or

208/240 Vac 3-phaseEfficient Energy Conversion is

Critical in a Solar Energy System

Protection and Conversion

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“DC” Storage Solar SystemOff‐Grid

DC Voltage0 to 500 Vdc

AC Voltage @ 60 Hz110 Vac 2-phase

Efficient Energy Conversion is Critical in all Solar Energy Systems

Protection, Conversion, and Energy Storage

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Individual Solar Systems• Solar systems can be grid‐tied or off‐grid

– Off‐grid systems act as a stand‐alone power system for a location. No external electric power grid is usually available or expected. 

– Grid‐tied systems would be connected to the house/company power grid and the local utility power grid. The power may be restricted to never source energy to the utility grid or it could be sourced/sold to the utility grid .

• Net metering involves a grid‐tied system that provides “surplus power” to the utility grid and the customer is compensated at a negotiated rate with the electric utility. 

• Net metering policies vary significantly from state to state and may even vary from year to year in a state.– MI LARA Net Metering Program web site

http://www.michigan.gov/mpsc/0,4639,7‐159‐16393_48212_58124‐‐‐,00.html

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Public‐Private or Utility Systems• Consumers Energy Solar Garden Subscription Program

– GVSU (3 MW) and WMU (1 MW) solar gardens– A monthly fee based on “solar blocks”.– https://www.consumersenergy.com/residential/renewable‐energy/solar‐gardens

• Community Solar Power Purchase Agreements (PPA)– A model for public‐private funding of larger solar installations– Investors fund and own the power generation, while a public entity 

enters a long‐term purchase agreement for the energy. – https://wmich.edu/sustainability/events/power‐purchase‐agreement

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WMU Educational Solar Garden

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Site Planning

SunEarthTools.com map view of proposedWMU Educational Solar Garden location 24

Two Residential Scale Systems• Solar Panel Array – 4950 Watt Rating– 18 Suniva (Saginaw, Mi) Solar Panels– 275 Watts per panel– Solar Energy to AC Power Inverter 

from Solar Edge (3‐phase)– Ground Area approx.

24 feet x 10.5 feet.

• Solar Shingle Array – 2700 Watt Rating– 45 Solar shingles from Luma

Resources (Rochester Hills, Mi) – 60 Watts per shingle– Solar Energy to AC Power Inverter 

from SMA America (3‐phase)– Ground Area approx.

32.5 feet x 9 feet

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Inverters Shutoff Switches

Solar Edge Inverter with DC Shutoff

SMA Inverter with DC Shutoff

AC Shutoff Switches and Enclosure

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Seminars and Education Opportunities

• If you are interested in seminars, training session, or tours on solar gardens and solar energy systems, Consumers Energy has provided funding to support this work.

• Please contact Dr. Brad Bazuin for details– brad.bazuin@wmich.edu

• For more information, visit:http://homepages.wmich.edu/~bazuinb/SolarGardenWebSite/MainPage.html

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Solar Energy Generation and Demonstration Systems

• This project has provided educational materials and hands‐on laboratory stations for solar energy and solar energy powered electronics. With a focus on high school education and community demonstrations.– Senior Design Spring 2017: Bradley Beerman, Jonathan Kellogg, and Caleb Martin

– Senior Design Fall 2017: Dustin Thomas Bremer, Andrew James Cabush, and Kyle Michael Christianson

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Voltage, Current & Power• An energy source provides voltage and current.– Voltage describes a potential that can do work.

– Current is a flow of electrons that do work.

– Power is the amount of work being done.

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Measuring Current and Voltage• We can measure them with Digital Multi‐Meters (DMM)

• Voltage is across the source or load

• Current passes through the load and meter

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Solar Energy and Solar Cells

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Power & Energy Conversion• Power from energy sources are almost always converted to more useful voltage levels and types!

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DC to DC Converter• SUNKEE DC‐DC Converter 

Module Step up and down – Input 3.5‐28V – Output 1.25‐26V Adjustable

• USB Cell Phone Charger– Basic ‐ 5V USB Boost @ 1000mA from 1.8V+

https://www.amazon.com/SUNKEE-Converter-3-5-28V-1-25-26V-Adjustable/dp/B008ATU2X8

https://www.adafruit.com/product/2030

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• The Raspberry Pi 3 is a small computer.

– A 1.2GHz 64‐bit quad‐core ARMv8 CPU, 1GB RAM, 4 USB ports, HDMI port, Ethernet port

• Sense Hat – 8×8 RGB LED matrix, a five‐

button joystick and includes a Gyroscope, Accelerometer, Magnetometer, Temperature, Barometric pressure, and Humidity https://www.raspberrypi.org/products/sense-hat/

https://www.raspberrypi.org/products/raspberry-pi-3-model-b/

Raspberry Pi “Computer”and Sense Hat Plug in Board

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Hot Wheels Battery Power Track• Hot Wheels Battery‐Operated 

Slot Track:– Battery pack modified to take 

solar inputs. Multiple solar panels provide additional power needs.

– Hot Wheels slot track accommodates 2 competitors includes 2 vehicles with 2 controllers.

– Track comes in lovely, hot orange color

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Thank you for your attendance!Solar Gardens and Solar EnergyKalamazoo Valley Museum ‐ Sunday Series: 11 March 2018

https://www.kalamazoomuseum.org/

Any Question?Please come see the demonstration material.

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Dr. Bradley J. Bazuin, Chair and Associate Professor, 

Electrical and Computer Engineeringbrad.bazuin@wmich.edu

http://homepages.wmich.edu/~bazuinb/(269) 276‐3141

ADDITIONAL MATERIAL

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PV Safety for FirefightersYou Tube Video on  Solar Photovoltaic System Firefighter Safety• Training video by Capt. Matt Paiss, of the San Jose, Calif., Fire Department, 

offering further understanding of the how solar electric systems work and tips on how to stay safe. March 1, 2011.

– Note: California codes and regulations differ from Michigan.– Useful visual references and precautions when encountered.

• Residential System Example– Part 1: https://www.youtube.com/watch?v=X1GXF8iQnyY , 8:06 min.

• Roof Mounted Commercial System Example, Summary and more examples.– Part 2: https://www.youtube.com/watch?v=cJsvkZj0scQ , 8:22 min.

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Additional Web Resources• UL Free on‐line course, “Firefighter Safety and PV Course”

– http://lms.ulknowledgeservices.com/catalog/display.resource.aspx?resourceid=352901

• You Tube Video: “Solar Photovoltaic Systems & Firefighter Safety”– A n expansion on previous videos from Captain Matt Paiss of the San Jose Fire 

Department. May 18, 2012– https://www.youtube.com/watch?v=K2EWQUPiXKc , 17:23 min.

• You Tube Video: “Solar Panel Safety for First Responders‐ Part 1 & 2”– Another set of videos from Captain Matt Paiss of the San Jose Fire Department. Nov. 28, 

2012.– Part 1: https://www.youtube.com/watch?v=ldzJIf4j8do , 22:39 min.– Part 2: https://www.youtube.com/watch?v=EaPadE2SIcI , 5:10 min.

• You Tube Video: “NFPA's Safety Information for Photovoltaic Panels”– https://www.youtube.com/watch?v=b_3TtswrUkw , 3:37 min.

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US Government Solar Information• Solar | Department of Energy

– https://energy.gov/science‐innovation/energy‐sources/renewable‐energy/solar

• National Renewable Energy Laboratory– http://www.nrel.gov/

• National Renewable Energy Laboratory ‐ Solar– https://www.nrel.gov/solar/

• US DOE SunShot Initiative– https://energy.gov/eere/sunshot/sunshot‐initiative

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PVEducation.org

• There are a number of on‐line resources with excellent graphical representations of how devices operate. See the following:

– 4.1 Light Generated Current– 4.2 IV Curve– 4.2 Open Circuit Voltage (Voc) & Short Circuit Current (Isc)– 4.4 Impact of Both Series and Shunt Resistance– 4.4 Effect of Light Intensity

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SunPower Solar Cell Data Sheet

SunPower Corporation, Document #001-66352 Rev** A4_en 42

SunPower Solar Panel

96 Series Connected Solar CellsVmpp 54.7 V, Impp 5.86-5.98 A

SunPower E-Series Residential Solar Panels | E20-327, Data Sheet, SunPower Corp., March 2016. 43

SunseekerWestern Michigan University’s

Solar Car Racing Team