Tankless heaters not only save several square feet of storage space—there’s also no stand-by energy losses and no sitting water. Typical tankless water heaters can be about 35 percent more energy efficient than traditional storage tank water heaters for a home that uses about 40 gallons of hot water a day.
Depending on the extent of their use, tankless heaters can yield energy savings of up to 50 percent if they are installed in a strategic and advantageous manner. Since approximately 15 percent of the total energy expenditure of typical households goes to heating water, the benefits can be far-reaching.
This is the logic behind the "tankless" or "instant" water heater, which provides on-demand and instantaneous hot water at an efficient and less costly rate. And though the intangible savings of fossil fuel pollution and water waste are not immediately apparent, the fact that energy and water are such indelible aspects of a home’s eco-footprint means that the water heater is an ideal target for those aiming to conserve.