How to Save Energy During a Heat Wave

According to the National Weather Service, a heat wave is officially defined as unusually high temperatures lasting more than two days. Extreme heat waves and warmer temperatures have become a more frequent issue in the last few years. In fact, June 2025 was one of the top three hottest Junes on record, coming in just below 2023 and 2024.

During a heat wave, it’s common for energy demand to spike as residents rely on their air conditioning to remain cool. Increased energy usage can not only create more expensive electricity bills, but it can also overwhelm the grid and lead to rolling blackouts. It’s important to properly manage your energy usage during a heat wave in order to stay safe and avoid unexpectedly high electric bills.

Heat waves can cause life-threatening risks to your health and safety. Extreme heat is most dangerous for young children, the elderly, and people with health conditions, but it can affect everyone, according to the Red Cross. Use the following tips to help keep yourself and your loved ones safe during a heat wave.

1. Limit outdoor activities

If there is a heat wave in your area, it’s best to avoid outdoor activities to limit the risk of overheating. Delay yard work, sports games, and other outdoor activities until the heat wave has passed. If you do have to go outside, dress in lightweight and loose-fitting clothes and keep yourself hydrated. Plan to stay in cool, air conditioned spaces. If you don’t have air conditioning in your home, consider spending time in a public space that will be cool, like your local library, shopping mall, or museum.

2. Prepare for emergencies

It’s best to prepare for the worst and hope for the best during a heat wave. Gathering emergency supplies in advance can make it easier to manage during a heat wave, especially if a power outage or rolling blackout occurs. Our Choose Energy experts recommend putting together an emergency kit with essential supplies including clean drinking water, non-perishable food, medications, and a first aid kit. Our power outage guide breaks down how to build an emergency kit in more detail.

3. Stay hydrated

According to the Red Cross, the average person should drink three quarters of a gallon of water daily to stay properly hydrated. During a heat wave, it’s important to drink enough water to keep your body hydrated and cool, especially if you have to go outside. Avoid drinking alcoholic or caffeinated drinks, as they can dehydrate your body faster.

4. Check before you lock

If you need to drive anywhere during a heat wave, be sure to check your car for children, pets, or passengers before exiting your vehicle. Taking the extra few seconds to check will give you peace of mind and ensure you avoid a tragic mistake.

While your health and safety are the number one concern during a heat wave, you also may be concerned with how the temperatures will affect your electricity bill. During a heat wave, you should continue to cool your home to keep yourself and your loved ones safe. However, it’s possible to manage the impact your AC has on your electricity bill.

It’s important to know that electricity rates often increase during extreme temperatures, so your energy bill could go up following a heat wave. If you live in an area with a deregulated energy market, you could lower your electric bill using the free Choose Energy marketplace or by following these energy saving tips.

1. Use ceiling fans

While ceiling fans won’t replace air conditioning, they can keep air circulating in your home and take some of the strain off of your HVAC unit. Using your ceiling fans may allow you to raise the temperature on your thermostat a few degrees, which can significantly lower your energy usage during a heat wave.

2. Seal doors and windows

Check your home’s window seals and weather strips around exterior doors to make sure there aren’t any gaps. This will prevent hot air from coming into your home and make sure the cool air doesn’t leak outside.

3. Schedule HVAC maintenance

Routine maintenance on your home’s HVAC unit will help to keep it running efficiently. Our experts recommend scheduling maintenance visits twice a year, in spring and fall. You can also contact an HVAC professional in your area for an inspection before a heat wave, if possible.

Another routine maintenance step is to replace your home’s air filters regularly. You can do this yourself without the help of a professional. Clean air filters can lower your HVAC’s energy usage by up to 15%, according to the Department of Energy, allowing your system to work more efficiently and you to potentially pay less on your monthly bill.

4. Run appliances overnight

You can lower your energy usage and limit strain on the grid by running appliances overnight. Peak hours of energy usage are normally from 7 a.m. until 11 p.m. during weekdays. Electric rates are often higher during peak hours of the day, but drop during off-peak hours. You could help to lower your utility bill by running appliances like your dishwasher or washing machine overnight or during off-peak hours.

5. Sign up for a cheaper energy plan

If you live in a deregulated energy market, you could lower your electricity bills by switching to a plan with a cheaper electric rate. Choose Energy offers a free marketplace where you can easily compare electricity rates and plans from providers in your area. Enter your ZIP code on this page to compare current electric prices near you.

What qualifies as a heat wave?

A heat wave is a period of time where the weather is abnormally hot, lasting two or more days. Heat waves are relative to the climate. For example, an abnormally hot day in Texas will likely be warmer compared to an abnormally hot day in Colorado. Be sure to check weather reports for your area to stay informed about upcoming heat waves.

What should I set my thermostat to during a heat wave?

The Department of Energy recommends setting your thermostat between 75 and 78 degrees during the day. Raising the temperature on your AC unit even a few degrees can help to lower your energy usage and limit the strain on the grid. But don’t sacrifice comfort in favor of savings; it’s important to stay cool and safe during a heat wave.

Why is my electricity bill so much higher in the summer?

In the summer months, residents often use more electricity as they rely more on air conditioning to cool their homes. The more energy you use in a billing period, the higher your bill will be. Managing and maintaining your AC unit regularly can help to keep your monthly bills in check.

How can I cool my home without lowering the AC?

Cooling your home is important during a heat wave, but it can also quickly drive up your electric bill. If you’d like to avoid lowering your thermostat, you can keep cool by turning on indoor fans, closing blinds and curtains, and wearing lightweight clothing.