by Patrick Appel
Farhad Manjoo is pumped about a soon-to-be-released LED lightbulb that gives off "light that looks exactly like what we're used to." They retail for $20 a pop but supposedly last 20 years:
On average, an incandescent bulb lasts about 1,000 hours—that's about a year, if you keep it on for about three hours a day. Electricity in America also costs about 11 cents per kilowatt hour (that's the average; it varies widely by region). In other words, a 50-cent, 60-watt incandescent bulb will use about $6.60 in electricity every year. Switch's 60-watt-equivalent LED, meanwhile, uses only 13 watts of power, so it will cost only $1.43 per year. The Switch bulb also has an average lifespan of 20,000 hours—20 years. If you count the price of replacing the incandescent bulb every year, the Switch bulb will have saved you money by its fourth year. Over 20 years, you'll have spent a total of about $142 for the incandescent bulbs (for electricity and replacement bulbs) and less than $50 for Switch's 60-watt bulb.