Saving Electricity&Water with High Efficiency Showerheads

Using high efficiency showerheads in the bathroom can save much household energy and water to the advantage of the householder, the environment and, under energy and water shortage circumstances, to the supplier.

Dr Amory Lovins, of the Rocky Mountains Institute, Denver, USA, (see www.rmi.com) says: “All studies on ‘pay-back periods’ of devices used in household conservation programmes conclude that the devices with the quickest pay-back periods are those that use hot water efficiently: High-efficiency showerheads and tap water aerators. These products are the ‘best buys’ for achieving savings and these are the products that should top the list of any efficiency programme.

“In a recent Eskom press release Eskom spokesperson, Andrew Etzinger, said that: “. . . there is a critical energy shortage in South Africa and citizens have an obligation to find more energy-efficient ways of living and working. Living in a semi-arid country where water is a scare and a precious resource, we should be doing more to conserve it. Switching from bathing to showering and using energy and water saving shower heads are the two simplest, most viable, affordable and effective ways for consumers to save water and electricity at home.”

“An energy and water saving shower head typically has a flow rate of less than 10 litres per minute, compared with a conventional shower head which has a flow rate of 15 litres per minute (lpm). By virtue of their much lower flow rate, energy and water saving shower heads effectively use less water. Because less hot water is used shower for shower, the geyser also consumes less electricity. This represents an opportunity for consumers to cut back on electricity and water consumption costs while conserving precious natural resources at the same time”, he said. “For the average South African household, water heating is the biggest monthly electricity expense, accounting for around 39% of the monthly electricity bill. Basically, the more hot water you use the more it costs you”, he said. “In a household that averages three 7-minute showers a day, using an energy and water saving shower head can save around 38 000 litres of water a year. “This translates into a saving of around R540 on an annual electricity bill and about R200 on annual water account,” said Etzinger.

But Etzinger’s statement that traditional showerheads deliver 15 litres per minute (lpm) may be an underestimation. SABS tests conducted in 1995 indicate that a traditional showerhead delivering water from a system with a pressure of 500 kPa delivers 48.4 lpm. (Source: SABS Report No.835/80476/M226 dated 23 Oct 1995.)

Test the flow rate of your currently fitted showerhead by opening the shower taps fully. Then insert a container under the stream for exactly 15 seconds and measure the contents collected in the container. Multiply this figure by four and you will know the flow rate of your traditional showerhead.
An energy and water efficient showerhead is not merely a low flow, (hot) water saving showerhead. Modern laminar-flow technology now allows for major savings in energy and water while enhancing the quality of the shower enjoyed by the user.

Best efficiency of showerheads is achieved through incorporating the optimum combination of the following criteria:

  • Determining how much water would be sufficient to achieve the objective. This is the (hot) water saving factor. It is usually achieved by the flow reducing design of the body or the spray face of the showerhead, limiting the maximum output of the showerhead at any pressure.
  • The maximum flow rate of an efficient showerhead should not be more than 9.5 litres per minute. Increasing the speed of the water delivered by the showerhead. The greater the speed at which the water arrives at its objective, the greater its rinsing efficiency.
  • Reducing the size of the droplets provided by the showerhead. Small droplets have a relatively larger total surface area than larger drops, thereby increasing the wetting capacity of the available water. Focussing the water onto the user’s body.
  • Traditional free flow showerheads tend to spray 50% and more of shower water wide of the user’s body, where it is wasted. High efficiency showerheads are designed to focus all available water on the user’s body, where it is needed.