We use energy star qualified CFL's - compact fluorescent light bulb. Not only do they save money but they use 75 percent less energy and lasts about 10 times longer than an incandescent bulb.
Lighting is responsible for one-fourth of all energy consumption worldwide - mostly non-beneficial night time lighting.The United States is the largest energy consumer in terms of total use and the per-captia consumption in the US has been pretty much consistent since the 70's. It is also referred to as light clutter, light trespass, over illumination, and light pollution. Yikes.