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			          Renewable & Non-Renewable Resources: Definition & Differences - Study.com
			           
			          We use a variety of Earth's resources, but not all of them will be around forever.
			            http://study.com/academy/lesson/renewable-non-renewable-resources-definition-differences.html
			         
			       
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			          Definition & Examples of Renewable Resources - SF Gate
			           
			          Renewable resources are an important aspect of sustainability. According to the U.S. Energy Information Administration, the most frequently used renewable resources are biomass, water, and geothermal.
			            http://homeguides.sfgate.com/definition-examples-renewable-resources-79625.html
			         
			       
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			          Top 10 Renewable Energy Sources
			           
			          There are many sources of energy that are renewable and considered to be environmentally friendly and harness natural processes.
			            http://listverse.com/2009/05/01/top-10-renewable-energy-sources/
			         
			       
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			          What is Renewable Energy, Types of Renewable Energy Sources - NRDC
			           
			          NRDC provides an interactive U.S. map highlighting the benefits of renewable energy resources in America. Get detailed county-specific information on renewable energy sources.
			            https://www.nrdc.org/issues/increase-renewable-energy
			         
			       
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			          Renewable Energy - Department of Energy
			           
			          Learn how the Energy Department's investments in clean, renewable energy technologies -- including wind, solar and geothermal sources -- are helping strengthen the American economy.
			            http://energy.gov/science-innovation/energy-sources/renewable-energy
			         
			       
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			          Wind, Solar, Hydro And Other Alternate Energy Sources For Home Power
			           
			          AltEnergy.org is helping public awareness of the coming energy crunch while working on creative solutions to ease the inevitable transition.
			            http://www.altenergy.org
			         
			       
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			          6 Things You Really Need To Know About Renewable Energy
			           
			          Clean Technica - 6 things you really need to know about renewable energy
			            http://cleantechnica.com/2012/03/30/renewable-energy-facts/
			         
			       
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			          How Much U.S. Electricity Is Generated From Renewable Energy?
			           
			          Energy Information Administration - EIA - Official Energy Statistics from the U.S. Government
			            http://www.eia.gov/energy_in_brief/article/renewable_electricity.cfm
			         
			       
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			          What Renewable Energy Source Has the Most Promise?
			           
			          What renewable energy source, if any, has the most promise for becoming a major energy source?
			            http://www.wsj.com/articles/SB10001424127887324485004578424624254723536
			         
			       
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			          Renewable Energy - Wikipedia, the free encyclopedia
			           
			          Renewable energy is generally defined as energy that is collected from resources which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat.
			            https://en.wikipedia.org/wiki/Renewable_energy