Sorry to have to burst your bubble NTL, but you'll still only end up with 1500 watts of heat. From thermodynamics, when you use the steam to perform work, you change its enthalpy (internal energy plus pressure times volume energy), during the process, and you end up with less thermal energy in the steam in the process. All known processes involving using steam to convert thermal or pv energy to work still obey the laws of thermodynamics, one of which is the conservation of energy. It was a good try however, but there is no free lunch there. Now if you could bring the water into your house, and then perform some process on it and kick it out of the house as cold ice with a lower internal energy, and keep all the electical power consumed as heat in your home in the process, then you would end up with more than the 1500 watts of heat in your home, but we are back to using a heat pump or something else to pull it off. Rich Hagen