Reducing Hot Water Use
One of the easiest and most sensible ways to cut your water heating costs is to simply reduce the amount of hot water being used. In most cases, this can be done with little or no initial cost and only minor changes in lifestyle. Some common-sense tips for reducing hot water use include:
- Use the lowest temperature wash and rinse settings on clothes washers. An average load of laundry uses about 121 litres (27 gallons) of water. Switching from hot to cold water will not only save the energy used to heat the water, but can also reduce fading and shrinkage of clothes.
- Front loading washing machines cut water use by nearly 40 per cent. A typical top-loading washer uses about 150 litres of water for each full load. In contrast, a full-size horizontal axis clothes washer uses only 75 to 100 litres. By purchasing a horizontal axis model, you could save as much as 26,000 litres of water per year.
- Install low-flow showerheads and faucet aerators. These devices regulate water flow and can save substantial amounts of both energy and water. Low-flow showerheads can reduce flow rates from around 23 litres per minute (5 gpm) (gallons per minute) to 9 litres per minute (2 gpm) or less, and are inexpensive to install. Hot water use for an average shower can be reduced from around 227 litres (50 gallons) to 100 litres (20 gallons) or less. There are a wide variety of low-flow showerheads available, including the popular pulsating or "massage" type. Some of these showerheads incorporate a valve or pushbutton that interrupts the water flow while "soaping up", saving even more.
- Take showers instead of baths. With a low-flow showerhead installed, showering may use only one-third the hot water of a bath.
- Operate clothes washers and dishwashers only when full. An automatic dishwasher typically uses about 30 to 53 litres (6 to 11 gallons) per cycle. Consider using the "light wash" cycle for lightly soiled dishes - it can save about 11 litres (2.5 gallons) per cycle. For smaller loads of laundry, use the lowest available water level setting.
- Fix any leaks in pipes or faucets. A leaky faucet can waste 11, 350 litres (2,500 gallons) or more every year. If the leak is in a hot water pipe or faucet, the energy savings should easily pay for fixing the leak.
- Don't leave hot water running while washing or shaving - this wastes both energy and water.
Reducing water use in general can also result in lower water and sewer costs, and can extend the life of plumbing equipment. Operating clothes washers and dishwashers only when full will also extend the life of these appliances, because they will ultimately be used fewer times.
Examples of Savings
If you heat your water with natural gas, it takes an average of about .09 GJ of gas to heat 379 litres (83 gallons) of water 50° C (90° F) (typical difference between incoming water temperature and water heater setting). That leaky faucet, wasting 11, 350 litres (2,500 gallons) a year, may only cost a few dollars to repair, but if the leaking water is hot it can cost you as much as $39 a year in fuel costs (assuming $11.50/GJ).
If your water is heated electrically, it takes about 22 kWh to heat 379 litres (83 gallons) of water 50° C (90° F). If you wash two loads of clothes per week, and can switch from hot to cold water, you could save as much as $42 or more per year (at $.07/kWh).
