Lingering in a hot shower is one of life’s pleasures, but heating water is a household’s second highest utility cost, accounting for 18% of the typical home’s energy use. Much of this energy is a standby loss because we heat water even when we are not using it.
Because replacing a water heater is often an emergency-driven decision, made without time to research, shop around, or order an appliance, the EPA recommends proactively replacing a water heater when symptoms of failure first appear or when it is over 10 years old. It makes sense to do the research on high-efficiency technologies in advance. The Dept of Energy’s “Selecting a New Water Heater” can help you assess the relative merits of conventional storage tanks, tankless, heat pump water heaters, and other types of appliances.
Electric heat pump water heaters (HPWH) are attracting attention today because of their exceptional ability to reduce energy bills and a homeowner’s carbon footprint. Depending on the size of the home and other variables, a typical family of four can save $550 a year or $5,600 over the life of the unit. While the upfront cost of an HPWH is higher, estimated between $1500- 3000 plus installation costs, the federal government provides a tax credit of 30% of the project cost up to $2000. Initial investment will typically be recouped in about three years, after which you’ll save hundreds of dollars a year for hot water. Energy Star’s guidance on tax credits and rebates can be found here.
A HPWH works like a refrigerator, but backwards. Instead of pulling heat out of the fridge and sending warm air into the surrounding room, the compressor draws heat from the surrounding room and concentrates it in your water tank. In order to work effectively, therefore, the heater needs to be in an environment with a 40-90 degree temperature range and 750-1000 cubic feet of air space. Hybrid models include an immersion heater to provide backup in periods of peak demand or if you have a houseful of guests.
One consideration of this technology is that it will make your basement (or other surrounding space) cooler, which might cause the furnace to kick on more frequently. The hybrid immersion models offset this during the coldest months. A knowledgeable contractor can tell you if your water heater space will work for a HPWH and assess the other relevant factors, including your electrical system. This is definitely a job for a professional, so be sure to seek out estimates and advice from several companies.
HPWHs are not suitable for all homes, and the initial investment is high. An alternative possibility is replacing a conventional storage heater with a tankless or on-demand heater. If you do need to purchase a conventional water heater, be sure to look for the ENERGY STAR label for the best fuel efficiency.
Water Saving Tips
Those of us on metered water are not only paying to heat it but also for the quantity we use, so it makes double sense to conserve. Fortunately, many strategies exist to save water and reduce those bills. As the EPA says, drops mean Watts!
In the Bathroom
Over 50% of water use takes place in the bathroom. Effective actions here include installing low volume shower heads, replacing old toilets with up-to-date, water-efficient models, and repairing leaky components. Look for the Water Sense label when purchasing new fixtures. Changing wasteful habits, such as showering instead of taking a bath, limiting time in the shower, and turning off the faucets while shaving or brushing teeth helps too.
In the Kitchen
The basic strategy here is to run the faucets as little as possible. Counterintuitive as it might seem, a modern dishwasher uses water more economically than washing by hand, so load those large items and let the machine do the work. When you do wash by hand, use a sink plug or a dishpan and turn on the faucet only when rinsing an item. Avoid leaving water running throughout. Using a compost pail rather than a garbage disposal also saves water. Finally, keeping drinking water in the refrigerator eliminates the need to run the faucet until the water is cold.
In the Laundry Room
Make sure you only run the washer with a full load or adjust the water level setting accordingly. While you may want to use a hot or warm wash for some heavily soiled or white items, most loads need only a cold cycle. In fact, using cold water not only reduces utility costs, but is also easier on your clothes.
Finally, most households should set their water heater temperature to 120 degrees, both to avoid scalding and save energy. Click on these links for more info about hot water temperatures and other tips on reducing water consumption.
Read the entire Good Energy Newsletter Fall 2023