How long does it take for your shower to heat up to a temperature of your liking? Personally, I always wait a few seconds (depending on the shower, sometimes a few minutes) before jumping into the shower--who really likes icy water first thing in the morning? Unfortunately, with traditional water heaters, this is a very inefficient way to start the day.

It is wasteful when just considering the water coming out of the showerhead. But when taking into consideration the rest of the water that must be heated in a traditional water heater, it's clear that those few seconds are worth a lot. Because traditional water heaters heat an entire storage tank full of water before any of it can come out of your showerhead, they typically heat much more water than is needed at a given time.

Essentially, conventional water heaters offer a ready reservoir of hot water (generally between 20 to 80 gallons). They operate by releasing hot water from the top of the tank when you turn your hot water tap on. Then, as water is depleted from the tank, cold water enters the bottom of the tank to ensure that the tank is always full. This water is heated inside of the tank by a heat exchanger as it is filled. Heater fuel sources for conventional storage water heaters include natural gas, propane, fuel oil, and electricity.

According to the U.S. Department of Energy, "because water is constantly heated in the tank, energy can be wasted even when a hot water tap isn't running." This is called standby heat loss. In other words, your traditional water heater is working overtime to heat water that you don't need to be warmed. Its surplus of heated water isn't used, and therefore energy used to heat the water is wasted. To put it even more simply: you are paying to heat extra water. Only tankless water heaters avoid standby heat losses.

Tankless Water Heaters, also known as "Instantaneous" or "Demand" Water Heaters, provide hot water to your shower or faucet only as it is needed. According to the Tankless Water Heater Guide, in a tankless water heater when a hot water tap is turned on, cold water travels through a pipe into the unit. There, either an electric element or a gas burner heats the water. As "a result, Tankless Water Heaters deliver a constant supply of hot water"--you don't need to wait for an entire tank to fill up and heat first.

So, if you are looking for a way to conserve energy (and water) in your home, you might want to consider replacing your conventional water heater for a tankless one. Here are the main things to consider before making the change:

Energy efficiency: Tankless water heaters use much less energy to heat the water you need to shower, bathe, and wash dishes and clothes. By only heating exactly the amount of water you need at a given time, standby heat loss is minimized and you never waste the water that would normally run down the drain while you wait for it to heat up.

 

Cost: While you do cut down energy (and therefore money) waste, tankless water heaters cost more than conventional ones, and their installation can be expensive. According to ConsumerReports.org, tankless water heaters are 22% more efficient than traditional ones, which can save you up to $80 per year for an average household. However, when taking initial costs and installation fees into consideration, you end up paying a pretty penny. Tankless heaters typically cost around $1,000, while traditional ones typically cost half that.

For help evaluating the cost of different water heaters and their installation, check out the U.S. Department of Energy's page on different water heater costs here.

Tankless water heaters are a great way to make your home more eco-friendly. If energy conservation is your priority, and you can afford the investment, I highly recommend making the switch! 

Check out Home Depot's

On Demand 7.4 GPM LP Gas Indoor Tankless Water Heater