Green electricityenvironmentalists to describe what they deem to be environmentally friendly sources of power. In particular green energy must be renewable and non-polluting. Green energy is generally considered to include:
For green energy to be truly "ecological electricity" it must not include medium or large-scale hydroelectric power (which could produce waste water) or sources of air pollution such as burning biomatter or petroleum.
In several countries, current electricity retailing arrangements make it possible for consumers to buy green electricity, either by purchasing their electricity from a generating company that uses only renewable technologies, or by buying from a general supplier who undertakes to buy at least as much power from renewable sources as their "green" customers purchase. Generally green electricity commands a price premium compared with standard supplies. Obviously this option is only available where common carrier arrangements have been put in place to allow competitive supply of power.
No power source is impact-free. For instance, concerns are raised over bird kills and in some cases noise pollution by windmills and over heavy metal use and associated mining damage by solar cells.