Heating and air conditioning likely account for a large percentage of your home's electricity usage. In fact, heating and air conditioning account for about half of the average home's utility bill. There are some things you can do to make sure you are not wasting money on heating and air conditioning.

The right unit: Make sure you have the right size air conditioning and heating unit for your home. Having an air conditioner that is too large will cool your home too quickly, which will cause it to start and stop frequently. A unit that is too small will run too often. Consulting a professional to help you select the right heating and air conditioning units for your home will save you energy (and money) in the long run.

Maintain your heating and air conditioning systems: No matter what kind of heating and air conditioning system you have, it will work better and use less energy if it is maintained properly. Change the filters as recommended, and have your heating and air conditioning systems examined by a professional annually.

Use natural solutions: You can use nature to heat and cool your home. Open windows to let air circulate throughout the house. Keep sunlight out in the hot months by using blinds, shutters, or blackout curtains. During the cooler months, you can warm your house by letting sunlight in. The savings in electricity will be worth the inconvenience of opening and closing windows.

Weatherproof your windows: One third of your home's total heat loss occurs through windows and doors. Consider replacing your windows if they are single-pane windows or are more than 15 years old. If you do not have the money to replace your windows, however, there are still things you can do to keep heated or cooled air from escaping. You can install weatherstripping to the cracks around the edges of your doors and windows. You may also want to consider installing low-e window film on the window panes, which will allow light to come in while keeping UV rays and heat out.

Install a programmable thermostat: Having a programmable thermostat can prevent energy waste. A programmable thermostat turns the heat or cooling to a more energy-efficient setting when you are out of the house, and turns the heating and cooling systems when you get home. If you don't have money for a programmable thermostat, you can achieve the same effect by changing the thermostat when you leave the house.

By making these adjustments, you can save money on your heating and air conditioning bill.