Hot water is a wonderful thing. It’s also surprisingly expensive.In fact, it’s the second-largest energy expense in most US homes: It accounts for nearly 20% of the overall energy use in the average home, according to the US Department of Energy.A heat pump water heater can help reduce those costs by up to 75%.Of course, you might not be in the market for a new water heater. Your old one may be working just fine. You probably haven’t even thought about it.Most people don’t spend their free time contemplating how their shower gets all nice and steamy in the morning—not until that water unexpectedly runs cold, as it did for me on that horrible Sunday morning right before Christmas when the water tank gave out and flooded the house.That’s just one reason why it’s generally recommended to start thinking about a new water heater before the old one fails on you.After researching this topic extensively, we’ve found a lot of scenarios where a heat pump water heater may be the best option for most homes.