Pub. date: 2011 | Online Pub. Date: May 04, 2010 | DOI: 10.4135/9781412973816 | Print ISBN: 9781412996822 | Online ISBN: 9781412973816| Publisher:SAGE Publications, Inc.About this encyclopedia
Gavin D. J. Harper
Green energy is power that is derived from natural energy flows, such as solar radiation, whereby there are no harmful, toxic, or other emissions that are deleterious to the environment. Green energy sources are ultimately more sustainable than fossil fuel–based power generation, as they are harnessing “ambient” energy and, as such, cannot “run out.” It must be noted that although green energy technologies represent an improvement on the technologies they supersede, no source of power is free of environmental impact. Although green energy is usually used in the context of electricity generation, “green energy” can in some contexts of application be used to provide mechanical drive directly and, in some cases, thermal energy. The term green energy may also be used to refer to technologies such as cogeneration and combined he at and power, which, although still producing some emissions and undesirable environmental effects, represent a substantial improvement in Green ...