LED bulbs are by far the most environmentally friendly. They use the least amount of electricity, they last the longest and they do not contain hazardous materials. If you’re willing to sacrifice on light quality and spend more upfront, choose this bulb.
 

Incandescent bulbs use the most electricity and fill up the landfills more quickly than the LED and CFL bulbs. If you’re going to use these, make sure to turn off your lights when you’re not using them or try to make use of natural light. And don't forget to recycle them.

CFL bulbs each contain about 5mg of mercury. You should use CFL bulbs only if you plan to recycle them. When these bulbs break in your home or in a garbage bin, mercury (which is very toxic to the environment and your health) is released.

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