lets say u wanna turn lights off to save power. is it worth the bother?
let's estimate it takes 15 seconds, and you save the light being on for 1 hour on average
100 watt bulb, 10 cents per kilowatt hour. that means 15 seconds is worth 1 cent.
multiply a bit. a min is 4 cents. an hour is 240 cents.
so, who wants $2.40, and who wants an extra hour of sleep?
or an extra hour of work, which will generate more than $2.40
and this neglects the human costs of people having to devote thought to remembering to turn the lights off, and such. which actually dwarf both the time and money amounts in question.
i suppose i should concede that for someone who obsessively turns lights off, trying not to will probably be costly. however, getting into such a state is bad.
oh here's a source on prices. looks like it's less than 10 cents.