There are currently two types of non-incandescent bulbs sold commercially: compact fluorescent (CFL) bulbs and light-emitting diode (LED) bulbs.

CFLs are the most popular because they are extremely efficient and also inexpensive. According to the Energy Star website (www.energystar.gov), if every American home replaced just one regular light bulb with an ENERGY STAR compact fluorescent light (CFL), we would save enough energy to light more than 2.5 million homes for a year and prevent greenhouse gases equivalent to the emissions of nearly 800,000 cars. CFLs have greatly improved over the past few years, and they now come in all shapes, sizes and wattages. However, the small amount of mercury (a potent neurotoxin) contained in CFL bulbs remains a problem for disposal and if breakage occurs.

For this and other reasons, many communities are turning to LED bulbs. Their light is in the same spectrum as daylight (and they are also available in many colors as well); they use only 2-10 watts of electricity; and they last up to 60,000 hours (that’s about 41 years if you use them four hours a day).  They generate almost no heat, turn on instantly, and focus light right where you need it.  Yes, they’re expensive ($30 to $60 each) but the savings in energy and replacement costs are significant.

Resources:

The Environmental Defense Fund has an online bulb locator where you can specify the type of fixture you have, the shape, brightness and color you want, and the program will find the perfect energy efficient bulb for you.