In fact, according to the Department of Energy, using energy efficient window treatments like “window awnings can reduce solar heat gain in the summer by up to 65 percent on south-facing windows and 77 percent on west-facing windows.”

Solar heat gain is basically the amount of heat your home takes in from the sun. If you reduce the amount of solar heat gain in your building, you can cut down your energy costs and keep your building cool without cranking up the air conditioner.

- Blinds: when used in the interior of the building, blinds can reduce solar heat gain by up to 45 percent.
- Awnings: as noted earlier, awnings on windows can reduce solar heat gain up to 77 percent on west-facing windows.
- Drop Screens/Shades: simple and easy to use, this shade product is considered one of the most effective window treatments for saving energy. For the greatest efficiency, use dual shades so that you can use them for cooling and heating purposes.
- Mesh Window Screens: these can “diffuse solar radiation, reducing heat gain in the summer,” according to the Department of Energy’s article on Energy Efficient Window Treatments.

The window treatments listed above are just a few of the options you have. You can also use things like shutters, storm panels, drapes, and overhangs. These treatments are great for office buildings and even restaurants with large windows.