Heat waves are no longer confined to the hottest summer months. This year, we started experiencing dangerous hot weather in some parts of the U.S. as early as June. And, as trends persist, it looks like they will continue well into fall.
Trends also show there are more heat waves, they last longer, and they bring more extreme day – and night – temperatures. The news is filled with stories about health effects, especially for vulnerable populations, including the very old and the very young. All this comes from climate change, and it is something we can address head on.
In the summer, electrical usage in much of the U.S. and Canada peaks from the use of air conditioning, a primary tool for keeping ourselves comfortable. We need to keep our families safe. But heat waves also lead, increasingly often, to power outages as high demand challenges the grid. We need to conserve energy even as we rely on it to keep us safe. So, air conditioning can’t be the only tactic to employ against extreme heat.
What are heat waves?
Heat waves are weather events where unusually high temperatures are recorded for consecutive days–but also nights, when a body should cool off to recover from the heat of the day.
In the U.S., the EPA starts with the temperature of the nine hottest days in July and August, the two hottest months. They factor in humidity, then define a heatwave as two or more consecutive days that exceed the 85th percentile of those high temperatures. Humidity must be included in these calculations, as humidity makes us feel hotter and makes it more difficult for our bodies to cool by sweating. This “apparent temperature” where you live is often discussed as the heat index or the “feels like” temperature.
Heat waves are of particular concern in urban areas due to the oven-like effect of urban infrastructure like roads, pavements and buildings that close off land and retain heat. In the past 50-60 years, the frequency and duration of heat waves has increased in urban areas across the United States and Canada, endangering health and resulting in spikes in energy use that challenge the grids and increasingly cause brown-outs or even power failures.
By 1961 in the U.S., most cities had started measuring temperatures consistently (often at airports), so that year is often used as a baseline to look at increases. According to NOAA, heat waves averaged just over two per season in 1961, and that number has increased to six since the 2010s (46 out of 50 cities). Average heat waves lasted three days, but in recent years they’ve endured for four days (and more) in 28 out of 50 cities. The average heat wave season is now 46 days longer than in the 1960s. They occur earlier in the year and endure later in 46 out of 50 cities, and these periods of unusual heat in late spring or early fall are more likely to catch people off guard, leading to more health risks. Finally, heat waves have become even more intense: In the 1960s, the temperatures of heat waves were 2°F above the local threshold, and now in 20 cities the average temperatures are 2.5°F above even as average thresholds are also rising.
How to save energy during a heat wave?
We need to preserve our own health and energy. All choices must keep this in mind, but there are a lot of options. Following are some reminders to help us all reconsider – and amend – daily habits for summer, generally, and heat waves in particular.
Staying healthy during extreme heat
Even small increases in extreme heat can contribute to increased heat-related illnesses and deaths, so extreme events are good times to rethink some of our habits to ensure we avoid ill effects.
Try to avoid going outside, especially for exercise or labor during the hottest hours of 3pm to 7pm. If you do go out, make sure you wear a hat or other head covering and keep a hydration kit handy that includes bottled water and electrolyte drinks, hand towels, a hand fan.
Use water to stay hydrated and also to cool your body. Avoid hot foods and focus on foods that help hydrate, such as raw fruits and vegetables.
Some of the biggest effects of a heat wave come from high night time temperatures, so your energy choices for night should make sure that your home allows you to cool off. Instead of cranking up the air conditioning, consider cool or lukewarm showers before bed and increased use of fans. Fans, especially ceiling fans, may not cool a room but they can make a person feel cooler as they circulate air around the body.
For Heat Wave Safety Information from the American Red Cross, check out this Red Cross Safety Checklist.
Saving energy throughout your home
We are all interested in conserving energy and saving money, but of course this becomes more difficult during an extreme weather event. Here are some ways you can save. You can rely on your Sense Home app to keep track of your energy and look for inefficiencies. And the Compare reports also let you see how well your home is doing against similar homes.
Start by keeping your home cool in ways that don’t rely solely on air conditioning. Keep sun, heat and humidity out of your home by closing curtains and blinds, and keeping windows closed when it’s hot. Did you know that brightly colored curtains and blinds reflect heat most effectively? This avoids the AC working harder to keep the space cool. Keeping AC filters clear is another way to reduce AC workload. Most filters are ready for cleaning every month or so. Turn up the AC temp and open windows when temperatures are cooler, during morning and later evening hours, and use fans to bring in that cooler air – or to expel hot air later in the day.
Cook wisely to reduce energy usage. Try reducing the use of the oven and stove top to help keep the kitchen cool. This may mean cooking outdoors, using smaller appliances (toaster oven), or planning more uncooked dishes. The Meter and Devices reports in your Sense Home app will confirm the differences here. Keep refrigerator temps to 36F to 38F degrees and the freezer at 15 degrees. You can even organize the items in your refrigerator to put things used most often nearer to the front, and reduce the time the door is open.
Reduce the temperature on your hot water heater, and overall avoid using hot water as much as possible. Heating water can account for up to 30% of a home’s energy use. Wash clothes only in cold water, during morning or late evening hours, and try to wash only full loads. And remember that cool or lukewarm showers can help keep you cooler.
Turn off lights (especially if they aren’t LED), computers, televisions, printers, monitors and other appliances when they are not in use. You may also want to simply unplug appliances you’re not using. Many of these will be included in your Other and Always On bubbles in the Sense Home app, so this is a good way to reduce the size of those bubbles. You can turn off the drying feature in your dishwasher and let dishes dry by themselves, and limit your use of the dishwasher and clothes dryer.
Did you know that your TV might be using more energy than necessary? The “Quick Start” may save a few seconds at startup, but it is always consuming power. You might also adjust the picture brightness to better match the light in the room, especially if you watch mostly in the evenings. And to stream movies, avoid using a game console, which uses up to 30x more energy; instead, use an internet-ready TV or an add-on device like Roku that uses very little power.
Reductions like these are especially important between 5pm and 9pm each day, when electricity demand is highest overall. And as always, you can adjust your thermostats as much as health and comfort permit. For each degree you lower your thermostat, you can use 3% less energy.