All electric resistance heating puts out an equivalent amount of heat. If it uses a quarter of the power, then it puts out a quarter of the heat. A 500 watt light bulb will put out about the same amount of heat. It is not "greener". The nice thing is that this product is the 24 lbs of mass, so the heat should be radiated more evenly over space and time than a 500 watt light bulb that turns on and off on a thermostat. The mass will even out the temperature differences between the thermostat's "on" and "off".