Let’s face it showers wash a lot of heat energy and water down the drain and there are an awful lot of them out there. Therefore making showers more efficient could really make a big difference to world energy and water use and that is just what might happen.
According to Yarra Valley Water (a water distributor in Melbourne's East) around 30% of household water use is sprayed from our showerheads and then is washed down the sinkhole. In units and flats, which don't have gardens, it's more like 36%. Then there's hot water use, hot water requires energy and the most common way to heat water is via a conventional electric hot water service with a resistive element or a gas hot water service. The water and power consumed by showers adds up over the nation’s 9 million odd homes.
Around half of all showerheads are low flow, since 2006 showers have had to be WELS rated for installation in new buildings under building codes, combined with council, state government and water authority exchange programs around half of showerheads are in the 9Litres/minute (L/min) ballpark with the other half still gushing water at a torrential 20L/min.
Enter the Methven Kiri Satinjet Ultra Low Flow which uses 4.5 L/min and is the lowest flow showerhead on the Australian market. But is it about to be usurped by a Kickstarter project that is the brainchild of some well-to-do Mexicans.
The Nebia has achieved over USD $2 million in funding to produce a showerhead that only requires 2.7L/minute - or so they claim. Started by a guy who owned a chain of fitness centers and his friend an engineer - (whose father just happened to be the former head of IBM Latin America). They set about looking at water distribution from the perspective of industrial applications and associated tooling, inkjet technology, some other technology from industry, you name it.
The Nebia Showerhead
The result is that they now have claimed to have shipped a number of units to their early backers, which happens to include Apple CEO Tim Cook. Not cheap though, with a price tag of USD$269 (AUD $365), compared to the 4.5L/min Methven which sells at $135; however the showerheads could be revolutionary and if they come to fruition we definitely want to offer them at Pure Electric.
To illustrate how efficient this new showerhead it’s worth ranking its performance against a representative sample of currently available showerheads in Australia.
|Shower heat Litres/Min||Water Use (7 min shower) (Litres)||Hot Water Use (Litres)||Energy used (kWh)||Annual(kWh)||Annual (kWh) with Sanden Heat pump||Annual(Litres)|
Energy and Water Usage table
The Nebia gives nearly an order of magnitude water saving (86%) and an energy saving of (73%) compared to a traditional (20L/min) showerhead. So basically you could imagine a hot water service that is half the size to account for the massive saving in the need for shower water.
So if Nebia’s claims stack up, then we can save 44,000 litres of water and 1MWh of energy (over a year). Therefore it might make sense to wait for it, and a proactive government program to replace all heads out there. In Victoria if an ordinary 7.5 litre per minute showerhead gets 2 Victorian energy efficiency certificates worth potentially $50, then a showerhead like this should get 3 VEECS.
If you can’t wait for the Nebia you can still buy the much cheaper Methven Kiri Satinjet Ultra Low flow – which based on my family’s experience (involving 7 showerheads so far) I can assure you isn’t like some kind of torture by needles of water, nor some weak dribble, like the low flow showheads of old.
And of course you can go a lot further - many of our clients buy a Sanden CO2 hot water heat pump which reduces hot water energy demand by 75% in itself compared to buying an electric or gas hot water heater. Indeed if you bundle a Methven Kiri Satinjet Ultra Low Flow showerhead with the Sanden it halves energy consumption again and as a bonus prolongs the life of the heat pump (which should already last around 15 years) as it makes the unit run half the time it would otherwise run.
Conclusion - If you have the money, can wear the risk and wait then get yourself a Nebia by joining the kickstarter – and tell us how it goes. Otherwise consider a Methven kiri satinjet ultra low flow which, depending on your existing water heater and shower use, can provide a 3 month to 2 year payback.
Matthew Wright has a Masters of Engineering (Sustainable Energy) and is a PhD Candidate at the University of Melbourne - Australian German Climate and Energy Centre. He is Executive Director of Pure Electric Total Home Conversions and Executive Director of Climate and Energy Research organisation Zero Emissions Australia
James Hutchison is Technical Director Pure Electric – The Power to be Free