sources

http://www.iecycle.org/blog/index.php/2010/02/pros-and-cons-of-renewable-and-nonrenewable-energy-sources/

http://www.dlist.org/burning-issues/energy-sources-what-are-the-pros-and-cons

http://www.conserve-energy-future.com/

costs
http://en.wikipedia.org/wiki/Cost_of_electricity_by_source

environmental impacts
http://en.wikipedia.org/wiki/Environmental_impact_of_electricity_generation