Use authoritative resources for your papers. Use online databases, for example, that include the full text of academic, trade and news journals.
Examples for the first paper: Use web sites from the Department of Energy or other credible sites.
Search for keywords such as: ELECTRICITY PRODUCTION or ELECTRICITY and GENERATION or ALTERNATIVE AND ELECTRICITY.
Also look up keywords SOLAR ENERGY, WIND POWER, etc. These are just a few suggested terms; try others that may be of interest.