Make Your Water Heater
More Efficient

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Quick Facts Affordability Cost Savings CO2 Reduction		Second only to space heating, water heating is a big energy user in the average home. Improve your water heater's efficiency by insulating the pipes, using an insulating blanket, lowering the water heater temperature to 60ºC or installing a high-efficiency water heater. For even bigger energy savings, install solar hot water heating. Affordability Improving your water heater's efficiency can be as easy as turning down your water heater thermostat (no lower than 55ºC and no higher than 60ºC) and insulating your pipes. If you have an old inefficient heater, replacing it with a more efficient unit will bring you the most long-term savings. Cost savings Replacing your traditional water storage heater with a solar water heater can add up to significant long-term savings. Environmental considerations Because water heating uses so much energy, it's an opportunity for big energy savings. Decreasing energy use can help reduce energy peak loads, thereby postponing or preventing the need for additional energy generation and distribution infrastructure, such as: dams, coal-fired power generation stations, and underwater electrical cables. Solar water heating saves even more electric or gas energy.

What you need to know

Conserve water
Insulate your pipes
Put a blanket on your tank
Efficient water heater temperature
Maintenance
High efficiency water heaters
Solar hot water
Tankless (on-demand) water heaters

Conserve water

• Your biggest opportunity for savings is to use less hot water.

Insulate your pipes

• Insulate your electric hot water tank and pipes to minimize heat loss. Improving the insulation on your electric hot water tank and pipes is an easy way to save energy.
• Insulate your hot water pipes. Insulating your hot water pipes will reduce heat loss and may even allow you to slightly reduce the temperature setting on your hot water tank.

Put an insulating blanket on your tank

An insulating blanket is affordable and relatively easy to install.

• The easiest way to find out if your tank could use extra insulation is to place your hand on the outside of it. If the tank is warm to the touch, it is losing heat (for storage water tanks, this is referred to as standby heat loss). If the tank is cool to the touch, you likely wouldn't benefit by adding extra insulation to your tank. If you have a newer hot water tank, you probably don't need to wrap it because they are usually well insulated.
• A gas-fired hot water tank should be wrapped by a heating professional. An insulating blanket can be effective on a gas-fired hot water tank, but it must be carefully installed. The top, bottom and burner compartment of the tank must all be kept clear. If the blanket slips, it could create a health hazard.

Lower your water heater temperature to between 55°C and 60°C

• Keeping your water heater thermostat no higher than 140°F (60°C) can also help to reduce hot water costs. Reducing your water temperature to 140ºF also slows mineral buildup and corrosion in your water heater and pipes. This helps your water heater last longer and operate at its maximum efficiency.
• Consult your water heater owner's manual for instructions on how to operate the thermostat. You can find a thermostat dial for a gas storage water heater near the bottom of the tank on the gas valve. Electric water heaters, on the other hand, may have thermostats positioned behind screw-on plates or panels. As a safety precaution, shut off the electricity to the water heater before removing/opening the panels. Keep in mind that an electric water heater may have two thermostats – one each for the upper and lower heating elements.
• Mark the beginning temperature and the adjusted temperature on the thermostat dial for future reference. After turning it down, check the water temperature with a thermometer at the tap farthest from the water heater. Thermostat dials are often inaccurate; so several adjustments may be necessary before you get the right temperature.
• If you plan to be away from home for three or more days, turn the thermostat down to the lowest setting or completely turn off the water heater. Note that after an extended period at a low temperature, it's advisable to empty and refill the tank to eliminate bacteria, and to run water to empty the pipes. To turn off an electric water heater, switch off the circuit breaker to it. For a gas water heater, make sure you know how to safely relight the pilot light before turning it off.
• Do not lower your water heater temperature below 55ºC to avoid the risk of developing harmful bacteria in your water system. The B.C. Building Code mandates that direct hot water equipment that is capable of heating to at least 45°C but not above 60°C shall be installed.

Water heater maintenance tip

• After consulting your hot water tank owner's manual, drain off a dishpan full of water from the clean-out valve at the bottom of your hot water tank to control sediment and maintain efficiency.

Taking it further

Purchasing an increased efficiency water heater

• If your hot water tank is warm to the touch, it's leaking heat. Investing in a new, increased efficiency hot water heater or another water heating option is likely a good option.
• Condensing hot water heaters are the most energy-efficient tank-style water heater and thus cost less to operate. In simplest terms, a condensing hot water heater recaptures the heat of the flue gases that normally get vented out, so less heat is lost out of the tank.

Install a solar water heater

• Consider installing a solar water heater. Solar hot water technology has the potential to be widely used in homes and businesses across B.C. A solar hot water system can meet approximately 50% of total hot water needs. Domestic solar hot water systems reduce the peak loads on electricity or gas heaters and can reduce the demands on utility infrastructure.
• Domestic solar hot water systems are designed to last 20 to 40 years, minimize environmental impacts and promote community economic development through the building of a sustainable economy.
• SolarBC offers some valuable incentives for the installation of a solar hot water system for your home.

  How do solar hot water systems work?

  • The supply of solar energy comes from radiation generated by the sun rather than just visible sunlight, so even cloudy days provide enough energy for a solar hot water system to be effective. In B.C., some seasonal heating loads can be met by solar alone. During winter months and on cloudy days, a solar heating system typically operates as a pre-heater in conjunction with a conventional hot water system.
  • Solar hot water systems convert sunlight into heat through solar collectors mounted on the roof. Water, or a water/antifreeze solution, carries heat from the collectors and pumps it through a heat exchanger to a tank for storage and subsequent use. A typical system requires up to six square metres of roof space for collectors. A sloped, south-facing orientation is ideal for the collector, with minimal shading from nearby trees or buildings.

Use a tankless, or on-demand, water heater

• The advantage of on-demand water heaters, or tankless gas heaters, is that you heat your water as you use it rather than paying to have it constantly heated in a tank, thereby saving on the standby energy losses associated with conventional storage water heaters. Savings on a natural gas on-demand water heater can be up to 30% compared with a natural-gas storage tank water heater.
• Note that the draw currently required by electric on-demand heaters exceeds the Electric Tariff; so tankless electric systems cannot be used by BC Hydro customers until the technology improves.
• An on-demand water heater, heats cold water using a heating element (heat exchanger) that is turned on by a flow-activated switch.
• Consider your overall water usage when deciding about an on-demand water heating system. Some smaller tankless water heaters cannot supply enough hot water for simultaneous, multiple uses in large households. For example, taking a shower and running the dishwasher at the same time can stretch a small tankless heater to the limit. To overcome this problem, you can install a "whole house" type tankless water heater, or install two or more tankless water heaters connected in parallel for simultaneous demands of hot water.
• You can also install separate tankless water heaters for appliances, such as a clothes washer or dishwasher that use a lot of hot water in your home, but there comes a point where it's just as efficient to use a well-insulated conventional electric water tank.
• Note that some tankless water heaters require a minimum flow before any heating occurs, which means that for short draws the water may not be hot. This can result in water waste as users run water to meet the minimum flow.

FAQ

What are the most important things to consider when selecting a water heater?
Consider the following to determine the right type and model of water heater for your home:

• Fuel type. The fuel type or energy source you use for water heating will not only affect the water heater's annual operation costs, but also its size and energy efficiency.
• Size. To provide your household with enough hot water and to maximize efficiency, you need an appropriately sized water heating system.
• Energy efficiency. To maximize your energy and cost savings, you want to know how energy-efficient a water heater is before you purchase it.
• Costs. It's also a good idea to estimate its annual operating costs and compare those costs with other energy-efficient models.

With all of the rain we get in B.C., is a solar hot water system a good choice?
Solar hot water is a growing industry around the world and not just in sunny, tropical climates. Japan and Germany are currently world leaders in solar markets, yet our B.C. climate shows greater solar potential than both Tokyo and Berlin. In fact, the solar potential in Vancouver is only slightly less than that of Miami, Florida. Miami has greater consistency of solar potential from month to month, however taken across a whole year; Vancouver's annual daily average solar energy production is only 8% less.