Technological advances bring improvement in water heaters

When most people think of  hot water heaters, they think of big, grey tanks sitting in garages. For decades this type of water heater, known as a storage water heater, has dominated residential water heating in North America.

Storage water heaters have three basic parts – a tank, a heat source, and a switch. The tank holds a given amount of water while the heat source brings it up to a given temperature. In New Mexico, natural gas burners are the most common heat source for water heaters, although electric heating elements are also used in cases where gas is unavailable or impractical. When the water in the tank gets gets to the proper temperature, which is normally around 120°, the switch throws and turns off the heat source.

However, storage water heaters have a couple of inherent drawbacks. First, they have limited capacity. Once the hot water in the tank is depleted, the burner needs time to bring up a new tank-full of water to temperature.

The second major drawback of storage water heaters is what is known as standby loss. As soon as a storage heater finishes coming up to temperature, it immediately begins losing heat to the surrounding environment. Eventually, it loses enough heat that the temperature of the water significantly drops, and the heater has to kick back on to bring it back up again. Modern, high efficiency water heater manufacturers combat this by lining the tank with the best possible insulation, but no matter how good the insulation is, the problem will never be eliminated.

an illustration of a tankless water heater

With new technology comes increased efficiency in water heaters

Advances in water heater design and materials have led to a few major innovations in hot water. For instance, tankless hot water systems eliminate both main drawbacks of storage water heaters. In a tankless water heater, the water is heated as it passes through the water heater, then immediately delivered where it’s needed. Since there’s no tank, there’s no supply to run out of, and there’s no standby loss. However, tankless water heaters still require electricity or gas to warm up the water, both of which cost money.

Check back soon for Technology and efficiency – the future of water heater design, part 2!