Green Certificates allow electricity customers to purchase the renewable attributes of a specific quantity of renewable energy. Green Certificates (sometimes called green tags or renewable energy certificates) are created when a facility generates electricity from renewable sources. Each unique certificate represents the environmental benefits of renewable generation and can be sold separately from the electricity. One Green Certificate represents the renewable attributes associated with one-megawatt hour of green power. The purchase of Green Certificates means power from renewable sources is added to the electricity grid, displacing conventional fuels, such as coal, nuclear or gas from the electricity system. Green Certificates can be purchased for locations throughout the United States. Green Certificates support the production of renewable energy sources and contribute to an improved, more sustainable environment - for the good of today and for the benefit of future generations.