The term for buildings that do not consume energy from conventional power plants and that produce zero carbon emissions. A zero energy building does not rely on supply from the energy grid because it uses its own means to harvest energy on site, usually through solar, wind or hydro power. Some buildings that use very little electricity from the grid can be called near-zero energy buildings or ultra-low energy homes. The zero energy approach to modern buildings is meant to reduce carbon emissions and dependence of fossil fuels.