The more cool air you lose, the harder your air conditioning unit works and the higher your electricity bill will be. Install blinds, hang curtains or get storm windows made to keep cool air from seeping out. Even mesh screens, on the outside of your home, will help deflect solar radiation. You might even consider replacing old windows that leak cold air and let in heat.
Of course, choosing a new electricity supplier or natural gas supplier does not mean you are replacing your utility. Your utility will still deliver whatever energy supply you choose, safely and reliably. Since your utility company depends on where you live, you don't have to worry about choosing a utility company. In general, utilities are responsible for maintaining the energy infrastructure. If you experience a power outage or see a downed power line, call your utility company. These are listed in the Utility Companies column below.