Fuel cell fuel cells so efficiencies vary, but most are between 40% and 60% energy efficient. However, when the fuel cell's waste heat is used to heat a building in a cogeneration system this efficiency can increase to 85%. This is significantly more efficient than traditional coal power plants, which are only about one third energy efficient. Assuming production at scale, fuel cells could save 20–40% on energy costs when used in cogeneration systems. Fuel cells are also much cleaner than traditional power generation; a fuel cell power plant using natural gas as a hydrogen source would create less than one ounce
Home fuel cell plants and transmission lines. Putting a home fuel cell system into homes has the potential to get people off-the-grid, play a significant role in energy efficiency, and reduce US dependence on foreign energy imports. Home fuel cell A home fuel cell or a residential fuel cell is a scaled down version of industrial stationary fuel cell for primary or backup power generation. These fuel cells are usually based on combined heat and power-CHP or micro combined heat and power MicroCHP technology, generating both power and heated water or air. A commercially working cell is called Ene-Farm in Japan and is