I should wait for all my incandescent bulbs to burn out before replacing them with low-energy fluorescents. Reality:
You'd be wasting a lot of money and energy.
Scientists Jeff Tsao and Mike Coltrin of Sandia National Laboratories calculate that you'd save money by tossing a new 60-watt incandescent and replacing it with a fluorescent.
Why? The money you'd save on your electric bill with the CFL would more than make up for the cost of both bulbs.
Over the CFL's 12,000-hour lifetime, you would save some $51. But what about the energy it took to make that incandescent bulb? It amounts to less than 1% of the total. "It's so small that you don't have to worry about it," says Tsao. -- E.F. NEXT: Products: O Christmas tree