If you have 20 65W can lights/downlights in your house on 8 hours a day, then per year that is: 20*65*8*365/1000 = 3796 KWh
Recall that 1 gallon of gas is 36.6 KWh
And if we recall that it takes approximately 3 times more fossil fuel to deliver 1 unit of energy at your house (power plants are inefficient), then the cans actually use 11388 KWh of “primary”/”source” energy.
That’s the same as using 311.15 gallons of gas. Visual 300 gallons of a gas for a second. Yikes!!!
Might be a good idea to switch to these LED versions ($25 at home depot–1 year cost payoff) using 10.5W instead of 65W. They would gulp the energy 6 times slower! And no mercury and instant on. (Our CFL can lights take a moment to warm up…)
– Visualize Energy