Several weeks ago, many of us learned the pain of living without air conditioning for the first time. But living with air conditioning can be a costly venture. The Department of Energy estimates that air conditioners use 5 percent of the electricity produced in the United States. It also estimates that air conditioning costs American home­owners more than $11 billion a year.

But whether you’re using window units or central air conditioning, there are always ways to conserve energy and keep costs down. “Taking a combination of steps, beginning when you first install your air conditioner, can help you save and use energy more efficiently,” said Karl Neddenien, spokesman for Dominion Virginia Power.

The Energy Department and Dominion Power have some valuable tips for keeping costs down during hot summer days. Read on for how you can tame high energy bills this summer.

Replace vintage air conditioners

Vintage may be hip in the design world, but when it comes to air conditioners, you should always update. According to the Association of Home Appliance Manufacturers, if you’re still using a 1970’s-vintage window unit air conditioner, you’re losing money. A room air conditioner carries an energy efficiency ratio (EER), or the ratio of the cooling capacity to the power. If you have old air conditioners with an EER energy efficiency of 5, you can cut costs in half buy replacing it with a new one with an EER of 10. So do a simple calculation: If your average annual bill is $260, your bill would become $130. Depending on the size of the unit and room (window units range from $100 to $500), your annual savings will pay for the unit in just a few years.

The programmable thermostat

Most people do not live their lives at home. There are large periods of time each day when you are out, not using your air conditioning. Then why is it running at full blast? According to the Environmental Protection Agency, you can save more than $150 annually on air conditioning by setting a programmable thermostat if you have central air conditioning. Some offer preprogrammed settings to regulate your home’s temperature, with the goal of decreasing use when you’re not at home or asleep. The same goes with vacations — choose a thermostat that allows you to use this function regularly.

The same logic can be used with window units.

Window units

“If you’re buying a window air conditioner, check the label to see how many square feet it is supposed to cool,” Neddenien said. Since air conditioners have to remove humidity while also cooling the air, it’s vital that you get the right size unit for the square footage of your room. That means measuring your room before you buy. Also, choose a window unit that has an energy-saving mode. This mode should be used at night, since you’re less concerned with the temperature once you’ve fallen asleep.

Don’t sweat: The little things

Energy experts remind us to close the blinds to windows to keep heat out. Also, closing doors to empty rooms helps contain cool air in the parts you need it. Electrical appliances, too, such as light bulbs and even computers will heat a room. If you’re leaving the house, make sure to close doors and turn off all electronics to contain cool air and keep temperatures low. Neddenien also recommends doing laundry or dishes at night or in the early morning when it’s cooler. “If cooking, try using the microwave. It uses energy but will heat food more quickly,” he said. Cold meals in summer are also a great option.

Home improvements

If you’re remodeling any parts of your home, the Energy Department recommends investing in LED light bulbs (which emit less heat) and also installing ceiling fans. The agency reminds us that fans are the least expensive way to cool buildings and can be coupled with room or central air conditioning. Also, older homes should be checked for air leaks routinely, and always at the beginning of summer. Visit the Energy Department’s www.energysavers.gov for information on how to check for air leaks and air sealing options.

Outside your home

If you’re planning on doing any home improvements, experts recommend planting shrubbery and trees around your house to prevent heat from coming in. The Department of Energy says trees “can be planted to the south of your home to provide maximum summertime roof shading.”

Air conditioning doesn’t have to be a splurge. Whether you have window units or central air conditioning, cut costs by ensuring that your house is insulated. A combination of preventing air leaks, keeping rooms dark and timing your air conditioning usage will help you avoid expensive utility bills.