Dear friends,

Considering the detrimental effect of pollution on our environment due to electricity production from fossil fuels, as well as the limited supply of fresh water, a device which reduces electricity consumption and water use is an attractive prospect.

Water-saving shower and tap fixtures are not a new concept, but for various reasons they have not made a significant appearance in the mainstream despite the proven benefits. An average household uses approximately 40% of their entire electricity consumption to heat water, and therefore reducing this would have significant cost implications.

A water-saving shower head works by limiting the output of water from your shower to between 6 and 9 litre/min, depending on the model used. Therefore, the potential to save is only really relevant should your water supply/ shower produce water at a rate of more than 10 litres/ minute. So to evaluate whether or not fitting one would result in savings, you should determine the flow rate in your own home.

This is easily done by measuring how much water comes out your shower per minute. To do this, get either a container with a known volume, like a two litre oil container or jug, and calculate how long it takes to fill up while under the shower head. Be sure so set the shower exactly at the pressure and temperature you normally shower at. If the 2 litre container fills in less than 12 seconds, you are using more water and electricity than you could be so you, and the environment, would benefit from a more efficient shower head.

There is a vast selection of water saving shower heads to suit any style and pocket, and they are readily available at most mainstream building supply stores, as well as on line. It is an easy and relatively cheap way to make a positive difference to the environment and your pocket.  They typically cost between R100 and R400 depending on what it is made of, obviously the better the material, the more you will pay. However with the potential savings, it will pay itself off in no time. Most standard showers have a female BSP pipe fitting screwed onto the standpipe. Therefore removing your existing shower head and replacing it with the new one should be straight forward exercise for anyone with even basic DIY skills and tools.

Now the question remains, will it affect the quality of your showering experience? We have experienced the frustration of a shower which does not produce enough pressure.  I have not personally tested one, but I have now bought my own and will be testing it this month, so standby for an update.

Calculating the water flow rate in your home
I carried this test out in my own house, and calculated my flow rate at 15 litres/minute, which is about average.  Eternally solar website (www.eternallysolar.com) provides a very nice, simple calculator to calculate the savings one could enjoy with the installation of a more efficient shower head.

Entering my 15 litres/minute flow rate in the online calculator, and selecting  the entry level R195 shower head, I could save almost R1900 a year with the default electricity and water prices the calculator recommends. Now be careful, this is based on the default values which the online calculator has recommended.  I used my own calculations to determine electricity savings, and the online calculator was pretty much spot on, however, the default values for water and waste water are somewhat overestimated. I would suggest consulting your actual rates account supplied by the council to work out the average price per kilolitre you pay for water, since this is based on how much water you use.

In my case, a two bedroom house with a small garden and only two people showering, my water and waste water account is significantly lower than the default calculator. If I insert my own calculated prices,  this amount is reduced to  about R1500 (my water price is about three times lower than the default). However this number is slightly misleading since the wastewater they refer to is sewerage, which is made up of all waste leaving the house. That said, the electricity savings alone in my household would be in the region R800, which means the showerhead would pay for itself in 4 months.

It should be noted the greater the saving in hot water, i.e. the higher the current flow rate, the greater the electricity saving would be. In my case, the shower would reduce the water I needed heated in half, therefore my savings are particularly high.

Other than the peculiar choice in default water prices, the calculator seems valid and would therefore give you a good idea on potential savings.

Download this article here.

©Gary Fahy, July 2009