Nobody has to tell you that central air conditioning is the superstar of consuming loads of energy and racking up the cost of your energy bills during the summer. But built-in swimming pools have developed a nice little energy-hog niche on their own.

According to Opower, homes with swimming pools use 49% more electricity per year, and 19% more natural gas, than their non-pool neighbors. Furthermore, it’s said that the 5.4 million swimming pools in the United States use somewhere between 9 to 14 billion kilowatt hours of electricity per year – more than is used by 11 individual states and Washington, D.C.!

So if you have a pool, make sure the filter and heater are only running when necessary. And if you don’t have a pool – well, we suggest you go swim at the neighbor’s.