Have all the hot water you want and never run out. That’s the appeal of a tankless water heater. Unlike a traditional hot water heater, a tankless unit doesn’t store any water. It heats on demand.

    On the one hand, Consumer Reports pitted two tankless heaters against three standard water tank heaters. The tankless models were more efficient — they used 22 percent less gas — but, they editors say, they’re not necessarily economical. These units cost a lot more to buy and they cost a lot more to install.

    On the other hand, normal household water heaters hold the water in a tank and continuously heat it, even when you’re not using any water. The temperature must stay warm while you’re sleeping, while you’re at work, and even while you’re on vacation if you don’t turn down the thermostat before leaving. A tankless hot water heater is “on demand heating”, meaning that the water is only heated as you need it in real-time - thus saving you anywhere from 10% to 50% on your water heating costs. Therefore, as for a long time plan, it seems more economical than normal household water heater.

    But no matter how high the price is, some day soon, we will have to adopt this type of technology out of necessity, before we have completely squandered the natural resources of future generations.