The heat made by old fashion light bulbs adds to the work your air conditioner needs to do to keep you home cool. If you have not switched to fluorescent lighting for your home, you are wasting money two ways. You are paying more than you should for light and paying more than you should for air conditioning.
The light bulb that Thomas Edison invented is a good heater.
It changes about 90% of the electrical energy that it uses into heat. The little bit of energy that is left gets changed into light. We all know that if you touch one of these bulbs when it is on you will get burned.
If we lived in a very cold climate and electricity was cheep light bulbs would be a good way to heat your house. But, it is not cold here in the summertime and electricity is expensive.
In low ceiling areas, like our homes, fluorescent lamps are a good choice. Plus, they don’t get as hot. Fluorescent lamps only change about 30% of the electricity that they use into heat. A bigger share of the power they use is changed into light. The result is you get the light you need at a lower cost and reduce the internal heat load in your home.
That makes them a good choice for lighting your house. They cost more to buy than standard light bulbs but they save money because they use less electricity and last much longer.
Changing to compact fluorescent lamps (CFL) when your light bulbs burn out is one way to lower your energy bill. A better way is to replace the good bulbs in the lamps that are turned on the most with compact fluorescent lamps. Kitchen and living room lights are a good place to start. Keep replacing lamps until they are all changed over.
A light that is turned off when not needed makes no heat and adds nothing to your home the electric bill.
It works the same way at work too.