Water heaters tend to be one of the top energy users in most homes. Installing a solar heater can cut hot water costs in half, according to the U.S. Department of Energy. Or you can use other technology to heat your water more effectively: A recirculation system moves hot water to fixtures quickly. That’s an important benefit, since much of the water we use for showering goes down the drain as we wait for it to heat up.

Investment: Solar water heater costs range from $1,000 to $5,000, depending on the size and style; you can buy a recirculation system for under $400.

With app-controlled systems, you can adjust lights and set thermostats remotely, making it easy to turn off anything not in use.

Investment: Smart lighting starter kits sell for under $100; smart thermostats cost less than $200.

Leak detection systems signal when your pipes malfunction—or, in some cases, if a tap is left running. Upon noticing any irregularity, the system will shut off the water, potentially preventing a flood and saving you thousands of dollars in home repairs.

Investment: Leak detection systems range in price from $200 to $2,000.

Low-emissivity (low-e) windows capture the sun’s warmth and then emit low levels of radiant thermal energy that help you heat your home—and reduce energy loss by up to 33 percent on average, according to the U.S. Department of Energy.

Investment: Expect your windows to cost about 10 to 15 percent more for low-e glass.

You can cut your energy bills by switching from traditional sources of energy to solar power—you could save as much as 50 percent, depending on your location and electricity rates. Installing solar panels can be pricey, though costs have dropped in recent years because of technology advancements and tax incentives.

Investment: Solar panels range from $3,000 to $30,000, depending on the size of your home, and the type and model you choose. Be sure to shop around for the best value for your needs.

Leaving a computer on 24/7 can cost you close to $80 a year in energy costs, while leaving a TV on half the day may cost even more. Energy monitors pinpoint how much energy you use and which devices drain the most power.

Investment: Systems vary in price and sophistication: You can monitor one appliance, or you can install a system in your main breaker to check the entire house.

Consider smart appliances. Smart refrigerators, for example, have a built-in computer that keeps track of what’s inside, helping you to avoid food waste and making your grocery runs more efficient. Or go for a smart dishwasher that can sense the level of dirtiness and load to provide a more efficient clean—saving water and energy.

Investment: Expect to pay upwards of $3,500 for a smart fridge and around $1,000 or so for a smart dishwasher.

If you’re considering an electric vehicle, know that you’ll most likely do most of your charging at home. While a regular home outlet will work, a charging station is considered faster and more efficient. When you install a charging station, your monthly electric bill will go up by $30 to $50, but it could make your home more appealing to a new generation of eco-conscious buyers.

Investment: In-home charging stations range from $1,000 to $4,500, depending on how your home is wired and the type of charging station you choose.