Agway energy Services % of each Energy source used to produce electricity

I am being asked to receive my electric from a secondary company, Agway Energy Services. They have informed me that their bill will be bundled together with my primary electric company’s bill. They have received a higher rating from the BBB than my primary company. However, being environmentally consciouses, I would still like to know what sources of energy they use to provide electricity and by what percent on average is each source used.