CFL BULBS GE100 CFL 11w

Compared to general service incandescent lamps giving the same amount of visible light, CFLs generally use less power, have a longer rated life, but a higher purchase price. In the United States, a CFL can save over US $30 in electricity costs over the lamp's life time compared to an incandescent lamp and save 2000 times its own weight in greenhouse gases.[1] Like all fluorescent lamps, CFLs contain mercury, which complicates their disposal.

 compact fluorescent lamp (CFL), also known as a compact fluorescent light or energy saving light  is a type of fluorescent lamp. Many CFLs are designed to replace an incandescent lamp and can fit into existing light fixtures formerly used for incandescents.