The fuel used for now is certainly (diesel), but it can not be denied that now many are making diesel engines with new energy. New energy is the use of solar energy, which requires a heat absorbent plate from the sun. However, this new power is still less developed because it is still difficult to manage gas and make a suitable machine.
Generator sets are electrical devices that use kinetic energy. Photographs on generators or power plants installed in community service offices. Genset function is as a backup of incoming electrical currents and can be adjusted as needed.
I'm sure there are larger experts and understand the electrical world and its development as discussed above. thanks. By @emrija.