High Efficiency Water Heater

A high efficiency water heater is an appliance that uses a reduced amount of energy to heat water for indoor occupant use.

According to ENERGY STAR, a hot water heater accounts for 15% of home energy use. High efficiency hot water heaters, such as those with the ENERGY STAR label, can reduce energy use by 10-50%.

It is important to note that hot water heaters are measured for efficiency, and contain an EnergyGuide label. The higher the Energy Factor (EF), the more efficient the water heater.

There are several high efficiency water heater technologies available.

Tank Water Heaters

Tank hot water heaters store between 20 and 80 gallons of hot water. While a large supply of hot water is available at all times, it uses excess energy to keep the water hot, even when no water is being used. These have the lowest upfront cost, though an energy efficient tank hot water heater produces the fewest energy savings over time, because the storage tanks are by nature inefficient. According to ENERGY STAR, a high efficiency tank water heater could save $500 over the lifetime (8-10 years) of the equipment, since it is 10-20% more efficient than the baseline.

Tankless Water Heaters

Unlike a conventional tank-type hot water heater, tankless water heaters do not store water. They contain large coils capable of heating water "on-demand" and continuously as needed. This reduces the amount of energy used, because the water does not need to be kept hot at all times. However, there are limits to how much hot water the heater can supply at once.

According to ENERGY STAR, a high efficiency tankless water heater could save $1800 over the 20 year lifetime of the equipment, since it is 45-60% more efficient than the baseline.

Hybrid Water Heaters

Hybrid hot water heaters use technology from both tank and tankless hot water heaters, making them more energy efficient, but also able to provide consistent hot water with even pressure. They use a small storage tank to treat cold water, and then the “tankless” part of the water heater only needs to raise the temperature from warm to hot, instead of cold to hot, saving energy.

These three hybrid hot water heaters are available on the market:

1. GE GeoSpring

The GeoSpring, General Electric’s hybrid hot water, is reportedly the most efficient hot water heater on the market. GE reports that it is up to 62% more efficient than a standard hot water heater.
The GeoSpring works by using an evaporator to draw ambient heat into the hot water heater, so it produces the same amount of heated water heater as a standard hot water heater but uses much less energy. It has several settings, including vacation, hybrid, and high demand to reduce energy use at times of low need and deliver the needed water at times of high need.

GE's GeoSpring provides the same amount of hot water as a standard water heater, but uses hybrid technology to reduce its energy consumption. Essentially, an evaporator draws ambient heat into the hot water heater, saving energy.

The retail price for the GeoSpring is about $1,399 and is estimated to save $320 per year in utilities, so it will pay for itself in about three years. It may be even less thanks to rebates from state and utilities. Check out General Electric’s savings tool to find out how long the payback period for your hot water heater would be based on the cost of electricity and eligible rebates.s.

2. A.O. Smith NEXT

The NEXT Hybrid Gas water heater is manufactured by A.O. Smith, one of the world's leading producers of water heating equipment. A.O. Smith calls the NEXT "the new milestone in water heating—built for the way people ACTUALLY live and use hot water". It has 90% thermal efficiency and sells for about $1500.

According to the company, "The NEXT Hybrid water heater features a patented heat transfer process that utilizes a secondary heat exchanger to capture the heated flue gas from the tankless unit and route it back through a buffer tank to extract additional heat. The combined effort of the two technologies creates a superior, more energy-efficient performance."

The NEXT lessens standby losses while also eradicating "cold water sandwiches", which are bursts of cold water from using "made to order" hot water heaters.

3. Premier

State Water Heaters manufactures over 500 water heater products for both residential and commercial use. Its Premier Hybrid Electric model, which is designed for residences, uses electricity to pull heat from the air and inject it into the water, giving it double the efficiency of a conventional electric hot water heater. It is available as a 60 gallon and 80 gallon water heater. The 60-gallon retails for around $1800, while the 80-gallon version is about $2700.

The Premier is ENERGY STAR qualified, meaning it meets strict requirements for quality and energy savings. ENERGY STAR qualified heat pump models can save almost $300 annually on home electric bills.

Solar Thermal Water Heaters

Solar thermal systems use the sun’s energy to heat liquid, which can then be used to heat domestic hot water. Depending on how a building currently heats its hot water, it can replace some or all natural gas, oil or electricity use.

According to ENERGY STAR, a solar thermal water heater could save $2000 over the 20 year lifetime of the equipment, since it uses 70-90% less energy than the baseline (since it replaces the energy source with solar thermal energy).

Heat Pump Water Heaters

Heat pump water heaters use electricity to move heat from the surrounding air to the water in the storage tank instead of heating the water directly. According to ENERGY STAR, a solar thermal water heater could save $900 over the 10 year lifetime of the equipment, since it uses 65% less energy than electric resistance water heaters.

Installing or Repairing Your Water Heater

If you are looking to install or repair your hot water heater, you will need to hire a water heater professional - it is not a do it yourself job.

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