Each 13-watt CFL, over the expected 10,000 hour life of the bulbs will save 470 kilowatt-hours (kwh) of electricity, as compared to 60-watt bulbs. This translates to a global-warming-fighting reduction of over 730 pounds of carbon dioxide. It also means a reduction of 1.6 pounds of nitrogen oxides (which contribute to ozone reduction, and acid rain) and 4.3 pounds of sulfur dioxide (which contributes to haze and acid rain), and makes significant reductions in other impacts of coal-produced power such as mercury pollution and destruction of forest and stream habitats in mining areas. Only 10% of the energy used by these standard bulbs contributes to light—the remaining 90% is heat.

LED (Light Emitting Diode) is a bulb that produces Light by using Narrow Band Wavelengths.  LED last 25,000-35,000 hours and a 7w LED = 14 w CF light distribution.  Visit https://www.energy.gov/energysaver/save-electricity-and-fuel/lighting-choices-save-you-money/led-lighting.  By 2027, widespread use of LEDs could save about 348 TWh (compared to no LED use) of electricity: This is the equivalent annual electrical output of 44 large electric power plants (1000 megawatts each), and a total savings of more than $30 billion at today’s electricity prices. Lights for a holiday tree can last 40 years.  As an additional benefit, LED bulbs do not have toxic mercury.

Comparison of costs based on 25,000 hours of light:

Watts used60147
Average cost per bulb123
Expected lifespan (hours)1200800025000
Bulbs to reach 25,000 hours2131
Total cost of bulbs over 20 years$21.00$6.00$3.00
Cost of electricity (25,000 hours at $0.12 per kWh)$135.20$41.60$24.00
Total estimated cost over 20 years$156.20$47.60$27.00

Lifetime cost savings by using a CFL – $46.89!

Average household uses 20-30 light bulbs

25 bulbs @ $46.89 savings each = $1,172.25