Saturday, February 13, 2010

Some advice on the Nordic Eco showerhead

I bought a Nordic Eco showerhead from The Cultivate Centre in Dublin on a money-back basis. I got that promise beforehand because at 50 euro, I didn't really fancy trying it and being stuck with something that doesn't work. I'm glad I did. This gadget may well be great but it is completely pointless for my shower.

In the brochure that comes with it, it says it will cut your shower from 22 litres/min down to 9 litres/min but it will still feel like a great shower. Sounds great. What I didn't realise is that my shower does only 4.5 litres/min! With the new shower head attached, nothing much changed and in fact the old shower head was better for that rate of flow.

The moral of the story is, if you're thinking about one of these, get a bucket or a jug or whatever and figure out how many litres/min your shower does before buying anything.

In hindsight I could have worked this out in advance, even without a bucket. It's a 10.5KWh shower. It takes 4000J to heat 1 litre of water by 1 deg C. I need to heat my water to about 40C and let's pretend it's starting at 0C (it's close enough in the winter). So it takes 40C*4000J/C = 160000J to heat 1 litre of my cold water to 40C. A shower that does that once per minute is using 160000J/60s = 2666W. So a 10500W can do that about 4 times per minute, i.e. about 4L/min.

5 comments:

Anonymous said...

I just figured out the same. Sales pitch of Nordoc Eco sounds great but I just measured my current "ordinary" Damixa Plus head and my current flow is about 4-5 l/min. :)

Philip said...

I question the wisdom of a product designed to chuck 30 degree water down the drain at either 4.5 or 22 l/min. Why isn't there a heat-exchange electric shower?

Fergal said...

Philip, absolutely. I looked into it a few years ago and found someone who had made their own. Heat exchange needs lots of surface area and surface area plus dirt and hair seems like a bad thing but I am not a plumber.

These guys seems to have a solution but it seems unlikely to retrofit an existing plumbing setup and at $500 for the smallest version, you'd want to know you were fitting it right etc.

There were plenty more results for my search, so maybe it's on the way.

It's hard to get people to spend 100 now to save 50/year seems to be the essence of most of this sort of thing.

home4eco said...

I recently bought this fantastic eco shower head. It only uses 4.5 litres of water per minute in comparison to my old head that used around 20 litres. It really is saving us money since we moved to a water meter after the kids left. It's called a Nordic Eco Shower, really is worth getting one. Must pay for itself just from the savings.

Fergal said...

@home4eco

Reading the advertising for this item, your site included, you would think that 6l/min or less was some kind of miracle achievement. Now I know that most electric showers use quite a bit less than this to start with. My one at least gives a perfectly good shower with its original shower head.