Fans, air conditioners, sitting in the shade – there are lots of ways to stay cool on hot days. Many options for cooling, like air conditioning, require energy. Two-thirds of US homes have air conditioners, and six percent of our average annual household energy use goes to keeping cool — with a national energy bill totaling $11 billion per year. Let’s take a closer look at air conditioning, its efficiency and a few alternative cooling options.
A Brief History of Air Conditioning
First up: air conditioners. Modern air conditioning technology was developed in 1902 by Willis Carrier in Buffalo, New York. Using the processes of evaporation and condensation, Carrier figured out a way to reverse heating systems. The air conditioner not only provided cool air, but also dehumidified the area being cooled, resulting in increased comfort. Not surprisingly, air conditioners became quite popular and allowed many people to migrate to warmer climates like the Sun Belt in the US. They also helped people in the tropics live more comfortably. The founder of Singapore, Lee Kuan Yew, was once asked to pick the most influential invention of the millennium; he chose not the electrical grid, not the Internet – but the air conditioner.
Reduce Energy and Stay Cool
As we’ve noted before, air conditioners can suck up a lot of energy. But there are a number of things you can do to help reduce the energy needed to keep you feeling comfortable (and will also help you save on your summer electric bill when electricity rates are often the highest).
Here are some of our top energy-reducing picks:
- If you are looking to buy new, look for ENERGY STAR appliances that are available in both room and central units.
- Make sure your home is properly insulated and sealed to keep the cool in.
- Install energy efficient window coverings, like awnings, drapes and special films, to block out solar heat.
- Use a programmable thermostat to help save up to 10 percent per year on heating and cooling costs (set it at 78 degrees when you are home and let the temperature rise while you are away).
- Use the grill instead of cooking in the kitchen to reduce indoor heat.
- In temperate climates, landscape with leafy trees to block the sun in the summer but let the light through in the winter.
- Make sure your air conditioning units or systems are properly maintained to keep them running as efficiently as possible.
Alternatives to AC
Another cooling technology for those in warm, dry climates is evaporative cooling (also known as ‘swamp coolers,’ since they make the air a bit swampy). These coolers use a steady stream of outside air to evaporate water contained in the unit, thus cooling the air. You can leave your windows open with this technology because the cool, steady stream of air coming in the house will help push the warmer air out. They are more energy efficient than traditional air conditioners, provided you are in a low humidity environment. Swamp coolers do continuously use water, so if you are concerned about increasing your water footprint, you may want to rethink this technology.
You can also rely on an energy sipping electric fan as an efficient cooling option. Fans work by moving air around and do not themselves change the temperature. When you sit in front of a fan (or below, if it’s a ceiling fan) you get cooled off by the wind chill effect and by enhancing the sweat evaporating from your body. Fans can also help blow warmer air out of your home to improve ventilation, but this works best if you are blowing hot air out of your kitchen or if it’s helping the ‘chimney effect.’ The fan will assist the chimney effect’s inclination to pull the warm air up and out of your house and allow cooler air to seep in below. A fan blowing in an unoccupied room — and not being used to help ventilate — is just moving warm air around. It's best to turn it off.
Finally, there are options if you are sweltering on a hot day without an electric fan, air conditioning or a swamp cooler. Take in a movie or head to a local shop to piggyback off of their air systems, but bring a sweater. Or find a shady spot with a breeze in your town’s park. And last, but not least, check out these reader suggestions that got them through the summer without AC — many involve creative uses of ice, like stuffing French braids full of ice cubes. Enjoy your summer and stay cool!