This is a longlife bulb. There were six of them in the recessed light fixtures in my office. Each of these turns 200 watts of electrical power into light and heat every hour. So for six of them, that's 1.2 kwh. On an average day these lights were on for five hours - that adds up to 6lbs of coal. Somebody please tell me my math is wrong!Today I got the tall ladder from the basement and replaced all six with six CFLs. Same lumen output, i.e. the room is just as bright as before. Each of these bulbs turns 18 watts of electrical power into light and a whole lot less heat. Same formula: 6x18x5=540 - that's the equivalent of .54lbs of coal.
That's a nice pile of coal that won't get burned this year.
That's a nice pile of coal that won't get burned this year.