PhilBiker wrote:Hey I have changed out most if the light bulbs in my house from incandescent to fluorescent.
Maybe in the winter incandescants are more efficient?
True, flourescents convert a much higher fraction of input power to light and thus require less power to generate the same amount of light as an incandescent bulb. However, ultimately all the power input to both types of fixture ends up as heat in your house (assuming your windows are shaded). There is no "double-duty"as you put it, light is just another form of energy that gets converted to heat when it's absorbed by the walls, floor, ceiling and furnishings of your house.
The thing is, that to get 1 Watt-hr of heat from electricity at your house takes 3 to 4 Watt-hours of energy at the power plant that generates it. Most likely, that energy comes from natural gas or coal. Meanwhile, your gas furnace puts 80-90% of the heat it generates into your house. Taken as a complete system, it's much more efficient to create the heat you need by burning it at your house than by burning it at the power plant .