Dept. of Energy News- DOE Releases New Report on Benefits of Recovery Act for Small Businesses in Clean Energy, Environmental Management Sectors March 17, 2010
- Secretary Chu Op-Ed on Energy Efficiency from the World Economic Forum March 16, 2010
- Department of Energy Issues Requests for Applications for Nuclear-Related Science and Engineering Scholarships and Fellowships March 12, 2010
- Treasury, Energy Announce Guidance for Tax Treatment of Smart Grid Investment Grants March 10, 2010
- NREL News
- Tool That Tracks Solar Installations is Open to All March 12, 2010
- High-Speed Pipeline Revs Up Biomass Analysis March 8, 2010
- Light Inspires Energy Efficient Building Design March 1, 2010
- Making Wind Turbines Builds Career Interest February 22, 2010
Current and future renewable energy topics explained and discussed.
Solar Electrical Power
Solar electrical power works by the conversion of light into other forms of energy. When you think of solar power the first thing that comes to mind is probably solar panels being used to generate electricity. This is known as photovoltaics. However, solar power is used for a lot more than just generating electricity.
Solar power has been used throughout human history for a variety of things:
* Heat engines: Concentrating light to generate heat to drive an engine.
* Space heating: Converting light to heat and trapping it inside buildings.
* Water distillation: Purification of water using evaporation.
* Water heating: Converting light to heat for warming water.
* Photovoltaics: Conversion of light to electricity for a variety of uses.
Light hits the solar panel and is absorbed by a semiconducting material like silicon. Some of the light is reflected back and lost but a special layer designed to reflect light back at the cell recovers some. Electrons (negative charged) come loose from their atoms (photoelectric effect) allowing them to flow through the material.
Solar panels have a special composition that only allows these electrons to move in a single direction. Now that this negatively charged electron has come loose in its place is a positive charged “electron hole” which flows in the opposite direction. The electron and “electron hole” move in their respective directions until reaching metal plates which are connected. This action creates direct current electricity.
The amount of knowledge that goes into understanding all the details of how solar power works could fill a book and many books exist that cover them more extensively. Check out the environmental impact of solar power as well. However, the above information covers all the basics of know about how photovolatic panels work. If you want to learn more about how solar panels work wikipedia has an excellent detailed explaination that goes very far into the science of each individual part.
I hope you’ve found my explaination helpful and have learned something here today. If you’re interested in other forms of photovoltaic energy you should look up concentrating photovoltaics (CPV) or fresnel lens sterling engines.