Looking for the most energy-efficient light bulb? Not sure whether to go CFL or LED? Still using incandescent bulbs? Thomas Edison will forgive your move to energy efficiency.
UM Go Green has the light bulb breakdown.
Compact fluorescent lights (CFLs), and light emitting diodes (LEDs) use about 25 to 80 percent less energy and last three to 25 times longer than the typical incandescent bulb (U.S. Department of Energy). To create the same amount of light, an incandescent bulb emits 60 watts of energy compared to 15 watts for CFLs and 12.5 watts for LEDs.
Cost Comparison*
|
|
LED |
CFL |
Incandescent |
|
Projected lifespan |
50,000 hours |
10,000 hours |
1,200 hours |
|
Watts per bulb |
10 |
14 |
60 |
|
Cost per bulb |
$35.95 |
$3.95 |
$1.25 |
|
Kilowatts (KWh) of electricity used over 50,000 hours |
300-500 |
700 |
3,000 |
|
Bulbs needed for 50,000 hours of use |
1 |
5 |
42 |
|
Cost of electricity (at 0.10 per KWh) |
$50 |
$70 |
$300 |
|
Total cost for 50,000 hours |
$85.75 |
$89.95 |
$352.50 |
*Costs may vary. Source: Eartheasy Solutions for Sustainable Living
Benefit Comparison
|
|
LED |
CFL |
Incandescent |
|
Long-lasting |
x |
x |
|
|
High quality light |
x |
x |
|
|
Cool temperature |
x |
|
|
|
Mercury-free |
x |
|
|
|
Efficient |
x |
x |
|
|
Cost-effective |
x |
x |
|
|
Environmental impact* |
Low |
Medium |
High |
*Replacing a single incandescent bulb with a CFL will keep a half-ton of carbon dioxide out of the atmosphere over the life of the bulb.
CFLs or LEDs?
While CFLs pay for themselves in less than six months (for LEDs, less than two years) and may be more cost-effective than LEDs, here are some of the limitations of this cheaper option:
- Sensitive to frequent on/off cycling, which wears down durability
- Must be covered or shaded from outdoor elements
- Contain small amounts of mercury, a toxic metal harmful to the environment and your health
