Can anyone out there help me out?
Fact checking our upcoming book, I was looking for some data on the total power consumed by lighting in the US. But at risk of looking like a dim bulb, I have to confess—I couldn’t figure it out!!
The Green Home Guide says that lighting uses 5 to 10 percent of household electricity. That lines up pretty closely with figures from the US Energy Information Administration (part of the US Department of Energy) which reports that, as of 2001, electric lighting represented almost 9 percent of total household power consumption.
But another branch of the Department of Energy says that lighting accounted for over 16 percent of electricity use in households, and 24 percent in offices and stores. Based on these figures, and after I add in industrial electricity consumption, it looks to me as if lighting represents about 17 percent of total electricity consumption in the country.
So that’s getting close to the 20 percent figure we used in our 1999 book, Seven Wonders. That book also noted that electricity consumption from lighting would be even higher, if you include the extra air conditioning that’s required by all those hot bulbs in your house in summertime. And, in fact, this New York Times story from earlier in the year cites figures that lighting consumes close to 22 percent of the nation’s electricity.
But that’s not the end of it: the Worldwatch Institute report says that lighting consumes 15 percent of household electricity, but up to 34 percent of the nation’s electricity overall!
Hmmm. So light bulbs represent somewhere between 5 percent of home electricity consumption, and 34 percent of total, economy-wide consumption. That last figure is a real outlier, so I’m inclined to discount it. Still, it’s quite a spread, and all from reputable sources.
Which leaves me baffled and, er, in the dark. So if anyone else can shed some light on the subject, feel free to illuminate me.
And how much energy is consumed in manufacturing those bulbs? (It would seem to me that a fluorescent bulb takes a lot more energy to manufacture (take both kinds apart and you will see that an incandescent is relatively simple compared to an incandescent.) An incandescent can easily be made to last for years (thicken up to filament just a little).