One of the easiest ways to keep your home cooler in the hot months is to be smart about your lighting choices. Super energy-efficient lightbulbs that are either CFL or LED create significantly less heat -- or none at all -- than old-fashioned incandescent bulbs. But according to the Environmental Protection Agency, only 10 to 15 percent of the electricity incandescent bulbs uses is to generate light; the remaining 85 to 90 percent creates heat. Keeping those light fixtures on heats up the house. Reducing heat sources in your home will help your home feel cooler and use less electricity in the long run.