Water Heaters

Water heating is the second-highest home energy cost for most households in Wisconsin.

Looking for ways to save? Try these tips.

No Cost

  • Use cold water to wash clothes.
  • Reduce loads. Wash a full load of dishes in the dishwasher. Wash a full load of clothes in the clothes washer.
  • Use short showers instead of baths.
  • Set water heater at 120˚F at your sink.
  • Turn gas water heater control down to vacation or pilot setting when gone for two or more days. Turn off electric water heater at breaker.

Low Cost

  • Replace showerheads made before 1994. Look for a style that uses 2.0 gallons per minute (GPM) or less.
  • Fix leaky faucets. Use faucet aerators to reduce water flow to 1.5 gallons per minute or less.
  • Insulate the first 5 feet of cold water pipes and all hot water pipes. Start 3 inches above the flue vent opening.
Higher Cost, Bigger Savings
  • Switch from electric to natural gas water heater. 
  • Look for an ENERGY STAR® water heater when it’s time to replace your current equipment.

Tankless water heaters

(Also known as on-demand or instantaneous water heaters.)

A tankless water heater with an Energy Factor (EF) of 0.83 can save about 25% on natural gas costs for water heating compared to a tank-style heater with an EF of 0.62. For the average Wisconsin home, savings are about $30 to $60 per year.

Potential advantages of on-demand heaters:

  • Save energy.
  • Never run out of hot water (within flow limits).
  • Should last longer.
  • Free up floor space.
  • Failed components can be replaced. When a tank leaks on a regular water heater, the whole water heater must be replaced.

Potential disadvantages of on-demand water heaters:

  • Cost more to buy and install.
  • Hot water often takes longer to arrive.
  • Can't provide a slow trickle or a splash of hot water.
  • May require bigger gas and water pipes or a larger gas meter.
  • Many plumbers do not install them.


Conventional water heaters

Most water heaters use natural gas or electricity to heat water stored in an insulated tank. Natural gas heaters generally heat water faster and cost approximately half as much to operate.

Water-heater efficiency is rated by an Energy Factor (EF). The higher an EF, the more efficient the heater.

Recommended Water Heater Efficiency  
Natural gas, 30 to 50 gallons: ENERGY STAR®-qualified
Electric, all sizes: ENERGY STAR®-qualified


Solar water heaters

Water heating is the most cost-effective way to capture and use solar thermal energy in the Wisconsin climate. Unlike solar home heating systems, solar water heaters make use of the long days and direct sun of summer.

Federal tax credits are available for qualifying renewable energy systems.


Heat-pump water heaters