Certified emission reduction (CER)

Whatever is generated by human activity.

Changes that are directly or indirectly attributed to human activity and alter the composition of the world's atmosphere and that is added to that caused by the natural climatic variability observed over comparable periods.

It is the energy derived from sources that do not use exhaustible fuels (for example, water – hydroelectric power, wind – wind energy, Sun – solar energy, tides, and geothermal sources). Some combustible materials, such as biomass, can also be considered renewable....