General:
http://www.conserve-energy-future.com/pros-and-cons-of-renewable-energy.php
http://alternativeenergy.procon.org/view.resource.php?resourceID=001792
http://www.dlist.org/burning-issues/energy-sources-what-are-the-pros-and-cons
Solar Energy :
http://www.conserve-energy-future.com/category/solar-energy
Wind energy:
http://www.conserve-energy-future.com/category/wind-energy
http://www.altenergy.org/renewables/wind.html
Geothermal Energy :
http://www.conserve-energy-future.com/category/geothermal-energy
http://energyinformative.org/geothermal-energy-pros-and-cons/
Biomass
http://www.conserve-energy-future.com/pros-and-cons-of-biomass-energy.php
http://energyinformative.org/biomass-energy-pros-and-cons/
Tidal:
http://energyinformative.org/tidal-energy-pros-and-cons/
http://www.renewablegreenenergypower.com/tidal-energy-tidal-power-pros-and-cons/