1. Red Rocks Community College ENY 130 Grid-tied PV Fall 2009 Module 1

2. The Sun is our Primary Energy Source – not an Alternative !!

3. What is a Watt? 1 watt = 1 amp x 1 volt

4. Energy vs. Power? “Watt” is Power “Watt Hour” is Energy Energy = Power x Time A Microwave uses 1000 watts while running, this is the Power it uses If this microwave runs for 1 hour, it uses 1000 watt hours of Energy = 1kWh

5. Watts up with Photovoltaics A PV array is sized at 1000 watts (1kW), this is the Power of the array If this array produces energy for 5 hours it produces 5000 Whr of Energy = 5kWh

6. Energy Terms 1 kWh/m² = 3.412 BTU/ft² = 3.6 Mega Joules/m² = 3600 kJ/m² 1 Langley x 0.0116 1 Peak Sun Hour Solar Constant is at outer atmosphere at 1367 W/m²

7. kW/m2 Surface Density of Radiant Energy

8. Electrical Vocabulary Voltage Amperage Resistance Watts Watt Hours

9. Photovoltaic Electric Principles Terminology: Electricity-Flow of electrons through a circuit Volt (V)- The unit of force (electrical pressure) that causes electrons to flow. Ampere or Amp (I)- Unit of electrical current flowing through a wire. 1 amp for one hour is 1Ah Watt – Unit of electrical power equal to a current of 1 ampere under the pressure of 1 volt.

10. Electricity is the flow of electrons: using a water analogy…. Copper wire can be thought of as a pipe Voltage can be thought of as the water Pressure Amperage can be thought of as volume or gallons per minute (gpm)

11. Terms expanded… Watt-hour: the electrical unit of Energy Kilowatt hour-refers to 1000 watt-hours and abbreviated as 1 kWh This could be 1 watt produced over 1000 hours or 1000 watts produced (or used) over 1 hour 1000 kW (Power) = 1megawatt = 1mW =778 households 1000 mW = 1 gigawatt = 1gW = City of San Francisco Or 750,000 homes (but you need the area of 2400 football fields) It takes 1.21 gigawatts to go Back to the Future.

12. Solar History

13. Everything begins with the sun

14. - Evidence of solar architecture goes back 2500 years to ancient Greek and Roman Architecture - 214 B.C. Archimedes is written to have used bronze mirrors to focus sunlight on ships to set them on fire. In 1973 the US navy is to have recreated this experiment and set fire to a wooden boat 50 meters away. Some History

15. Burning Mirrors Source: Renewable Energy Fair

16. Myth Busters/MIT experiment Source: MIT

17. Anasazi Cliff Dwellings 600 A.D. – note solar orientation (summer)

18. 1839 - Edmond Becquerel discovers photovoltaic effect, at the age of 19, but the discovery was not useful to anyone

19. 1873 Willoughby Smith Discovered the effects of sunlight on selenium rods while working with telegraph cable

20. History continued…. 1914: The existence of a barrier layer in a PV device was observed 1918: Czochrolsky developed a way to grow single-crystal silicon 1923: Albert Einstein won Nobel Peace Prize for describing theories of Photoelectric effect in 1904

21. Photovoltaic – The process of turning light into electricity

22. Solar irradiance 1927: measuring sunlight to determine level of pollution. New York atmosphere was blocking almost ½ of the sunlight

23. (1931) Thomas Edison in conversation with Henry Ford and Harvey Firestone “We are like tenant farmers chopping down the fence around our house for fuel when we should be using Natures inexhaustible sources of energy — sun, wind and tide. … I’d put my money on the sun and solar energy. What a source of power! I hope we don’t have to wait until oil and coal run out before we tackle that.”

24. 40’s - Bell Labs PV technology Source: Bell Labs

25. 50’s – Bell labs continued Battery systems Source: Bell Labs

26. Into the 60’s Solar Cells make advancements in space technologies

27. The 70’s 1975: U.S. began Earthbound PV and research and development 1977: Solar Energy Research Institute (SERI) later named National Renewable Energy Laboratory (NREL) opened in Golden Colorado.

28. 1970’s – 1 st Solar Concentrator power plant

29. 70’s continued space development

30. 70’ – 80’s Popular opinion attributes PV system use predominantly in the Emerald Triangle region of Northern California. These residents were engaged in agricultural pursuits that spurred PV innovation while maintaining their independence from the grid.

31. Late 1970’s – Federal Tax incentives give boost to solar thermal Mid 1980’s (Reagan) end of Federal tax incentives. This greatly slows solar thermal progress as a heat source Because of the incentives many flash-in-the-pan companies installed systems of poor quality giving solar a poor reputation

32. 1980’s – Concentrator Solar (thermal) power plants Kramer Junction, CA

33. 80’s to 2000’s Inverter technology progresses Square Wave inverter Modified square Wave True Sine Wave

34. 1990’s: the grid tied inverter…. Converts Direct Current produced by PV to usable Alternating Current

35. 2000’s – Photovoltaic (PV) Technology becomes more available and affordable

36. And then Building Integrated systems

37. 2004 – Colorado Voters approve Amendment 37 to have Energy providers offer rebates for installation of PV systems Habitat for Humanity house in Wheat Ridge: 1200 sf $147,000 plus donated items 4kW PV 96 sf of collectors w/ 200 ga storage tank Designed heat load: 4.4 kWh Annual Energy Savings : 96 MBTU (128,130 kWh)

38. 2007 – Nevada Solar 1 concentrator power plant comes online 64 megawatts capacity 300 acres 134 million kWh/year Cost 266 million

39. Fossil Fuel Elect. Generation Plants Are only 30-35% efficient Which does not include the mining and transport of fuel And does not include dealing with the toxic wastes Solar, though seemingly expensive, is delivered freely, abundantly, has no waste byproducts AND is up to 20% Efficient

40. The Future?? PV efficiencies of 20% now, can we get to 50% or even 100%? Silicon cells have a 29% theoretical maximum. Storage of electricity…better batteries, Spinning storage? Energy Saving lifestyles – Living Light ! Buildings that produce energy instead of using energy.

41. Solar Electrolysis for Hydrogen Fuel Cells

42. Application of Solar Energy Technology

43. Uses for Solar Energy Heating Air Conditioning Electricity Water Pumping Remote Power/Heat Grid Power/Heat Desalination Transportation Food cooking/Processing Space Applications All Earth Applications

44. Power and heat for homes

45. Transportation

46. Street Lighting

47. Hybrid Solar Lighting Sunlight direct

48. Security Cameras

49. Battery Charging

50. Remote Power

51. Very Remote Power

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