The ordinary incandescent light bulb remains the most popular form of home lighting because it is so affordable.  But it is also very inefficient, with 95 percent of the electric current  being converted into heat, not light.  

A 20-watt compact fluorescent light (CFL) provides as much light as a 100-watt incandescent bulb and lasts about 8 times longer.  Though a CFL will cost approximately 10 times more to buy than an incandescent bulb, over its average life of about 5 years it will use roughly a quarter of the power and save more than 1,400 pounds in greenhouse gases. 

Lighting in the average American home consumes 20 percent of the average household’s electricity bill.  A lighting store can generally advise on the best product for your needs, with a better-quality CFL lasting up to five times longer than an inexpensive one.  Using new lighting technologies can save between half to three quarters of your home lighting energy use – and if every home in America changed just one incandescent bulb to a CFL, we’d save enough energy to light seven million homes and prevent greenhouse gas emissions equal to that of one million cars.