The energy sources the companies use vary. All of them include some wind and hydro power. Other sources include solar and biomass, a category that includes landfill gas and other plants that create energy from organic sources. All of the electricity either comes from New England or from neighboring states, in which case it must be delivered into the New England electric grid to be part of this program.

Some of the products are Green-e certified, indicating that they have undergone an independent certification process through the non-profit Center for Resource Solutions. The Green-e process ensures that the companies and products meet consumer protection and environmental standards. For more information, see www.green-e.org or call 1-888-63-GREEN.