Water Heating
According to the Dept of Energy. Water heating can account for 14%–25% of the energy consumed in your home. You can reduce your monthly water heating bills by selecting the appropriate water heater for your home or pool and by using some energy-efficient water heating strategies.
Wash only full loads of dishes and clothes.
Take short showers instead of baths.
Lower the thermostat on your hot water heater to 120° F.
You might qualify for tax credits or rebates for buying a solar water heater. Visit the Database of State Incentives for Renewable Energy Web site and see.
Heat pump water heaters are very economical in some areas.
Consider natural-gas on-demand or tankless water heaters. Researchers have found savings can be up to 30% compared with a standard natural-gas storage tank water heater.
Consider installing a drain water waste heat recovery system. A recent DOE study showed energy savings of 25% to about 30% for water heating using such a system.
Buy a new energy-efficient water heater. While it may cost more initially than a standard water heater, the energy savings will continue during the lifetime of the appliance. Look for the EnergyGuide label.
Although most water heaters last 10-15 years, it's best to start shopping for a new one if yours is more than 7 years old. Doing some research before your heater fails will enable you to select one that most appropriately meets your needs.
Drain a quart of water from your water tank every 3 months to remove sediment that impedes heat transfer and lowers the efficiency of your heater. The type of water tank you have determines the steps to take, so follow the manufacturer's advice.
Install heat traps on the hot and cold pipes at the water heater to prevent heat loss. Some new water heaters have built-in heat traps.
If you are in the market for a new dishwasher or clothes washer, consider buying an efficient, water-saving ENERGY STAR model to reduce hot water use.
Insulate the first 6 feet of the hot and cold water pipes connected to the water heater.
Insulate your natural gas or oil hot-water storage tank, but be careful not to cover the water heater's top, bottom, thermostat, or burner compartment. Follow the manufacturer's recommendations; when in doubt, get professional help.
Insulate your electric hot-water storage tank, but be careful not to cover the thermostat. Follow the manufacturer's recommendations.
Take more showers than baths. Bathing uses the most hot water in the average household.
Lower the thermostat on your water heater; water heaters sometimes come from the factory with high temperature settings, but a setting of 120°F provides comfortable hot water for most uses.
Repair leaky faucets promptly; a leaky faucet wastes gallons of water in a short period of time.
Install aerating, low-flow faucets and showerheads.
Select a shower head with a flow rate of less than 2.5 gpm (gallons per minute) for maximum water efficiency. Before 1992, some showerheads had flow rates of 5.5 gpm, so you might want to replace them if you're not sure of their flow rates.
Insulate your hot water pipes, which will reduce heat loss and can raise water temperature 2ºF–4ºF hotter than uninsulated pipes. This allows for a lower water temperature setting.
Lowering the thermostat on your water heater by 10ºF can save you between 3%–5% in energy costs. Most households only require a water heater thermostat setting of 120ºF, or even 115ºF.
Did you know that 85-90% of the energy from hot water is wasted when it goes down the drain? Install a drain-water heat recovery system to pre-heat new water using the heat from drained water.
If heating a swimming pool, consider a swimming pool cover. Evaporation is by far the largest source of energy loss in swimming pools.

Hot Water