Our energy is mostly produced from non-polluting, renewable sources such as solar, wind, geothermal, hydroelectric, and bioenergy. The projects that produce our electricity are located in California, Oregon, and Washington State. The exact proportion of each varies with time, based on demand and availability. For example, MCE may use a higher proportion of hydroelectric energy during the spring and summer months when winter run-off generates more power at affordable prices. More information on power sources.