Energy Adviser: Low-flow shower heads can reduce costs



What do I need to know about energy-saving low-flow shower heads? Do they really save money? What are the trade-offs?

Heating water for bathing and washing clothes is a major home energy cost, representing about 17 percent of the total power bill for the average three-bedroom, two-bath, one-level Clark County home. The cost of heating water to 120 degrees ranges from about $27 to $38 a month for an average family of four.

Using less hot water — and less energy to heat water — is a good way to reduce your monthly power bill.

That might include installing low-flow shower heads that can cut your hot water usage from as much as eight gallons a minute to a low-flow standard of 2.6 to 1.5 gallons per minute.

There are trade-offs in terms of comfort, so it is important for consumers to consider options before buying a low-flow device for the shower. Manufacturers have responded to some of the concerns with new products that allow you to temporarily shut off the water flow and to adjust water pressure and volume. Some shower heads aerate the water flow, creating more water pressure.

Gallons per minute

When shopping for a low-flow shower head, first compare the gallons per minute rating, called the “gpm,” recommends DuWayne Dunham, an energy counselor for Clark Public Utilities.

“Also, check for a valve that allows you to temporarily shut off the flow of water,” he said. “This is a nice feature that allows a person to save even more water and is usually used when shampooing your hair, or in between rinsing.”

Pat Gornowicz, assistant store manager at Grover’s Electric & Plumbing Supply in Vancouver, said water volume is the main issue for consumers when looking into low-flow shower heads.

“They want to know the trade-offs,” he said. “At 1.5 gallons per minute, you get less than half the water volume you may be used to. So, if you have long bushy hair, it may take longer to rinse out the shampoo. The idea is to not stay in the shower longer to make up for low-flow.”

Grovers sells a line of low-flow shower heads that range in price from $4.25 to $16.16. Some low-flow devices marketed online and through big-box retailers claim that they allow you to conserve water without sacrificing comfort. Those shower heads are more pricey, ranging from $38 to $60 and up.

The good news, says Gornowicz, is that consumers appear to be doing their homework before buying a low-flow shower head. “They understand that there are some sacrifices in going green and saving energy,” he said.

How to compare

You may want to find out what your current shower head flow is so that you can compare it to a low-flow device. To do that, the U.S. Department of Energy suggests placing a bucket marked in gallon increments under your shower head. Then turn on the shower at the normal water pressure you use. Time how many seconds it takes to fill the bucket to the one-gallon mark. If it fills up in 15 seconds, your flow-rate is about four gallons per minute. If it fills in 10 seconds, the flow rate is about six gpm.

People whose shower heads take less than 20 seconds to get to the one-gallon mark could benefit from a low-flow shower head, according to the Department of Energy’s website, which says “A low-flow head should take 24 seconds or more to fill.”

Federal regulations mandate that new shower heads can’t exceed more than 2.5 gallons per minute. New faucet flow rates can’t exceed 2.2-2.5 gpm, depending on pressure of the water.

Energy Adviser is written by Clark Public Utilities. Send questions to or to Energy Adviser, c/o Clark Public Utilities, P.O. Box 8900, Vancouver, WA 98668.