Running Hot and Cold

Ah! The delight of jumping into a shower to freshen up before going out or to clean and relax you before bed :).

But what if you that the water’s a bit more refreshing than you anticipated (read: cold)?

I had that experience just the other day.  Changed my mood, just a bit :-|…

What had happened?

Living with solar hot water

It had been a beautiful, sunny day, so there should have been plenty of hot water.

(We have solar hot water for over 18 years…and it means we are just a little more aware of the weather each day.)

And my eldest teen had her shower in the middle of the day.  So there was plenty of time for the sun to heat the mix of remaining hot water and ‘new’ cold water in the tank properly.

…and teens

But…what I hadn’t counted on was that she had completely drained the hot water tank…and there was insufficient time for the water to heat.

So…I learned that in early spring half a day of sunshine where I live (inland at 35oS) is insufficient to heat 300L of water using flat plate collectors.

At least there was one good thing about this little adventure : she had not  turned on the booster when she went to have her shower. (Our booster is gas, chosen for lower greenhouse gas emissions compared with electricity generated using coal.  It works a bit like instantaneous hot water…except that we have to wait about 20 minutes for a full tank to heat.)

Turning on the booster every time they have a shower is a relatively new practice my children have developed in their mid-teen years.

It has been a real challenge trying to stop this habit forming.

Changing habits

First I wrote on the switch plate ‘DO NOT TURN ON UNLESS TODAY HAS BEEN CLOUDY’.  Not much difference.

Then I stuck a fluorescent pink Post-it note on the plate.  It said:




Still no change…until the evening I went to shower and wash my hair before going out!

But showering in luke-warm water is a small price to pay for one of my children (re-)learning how to operate our hot water system.


After all, we do get our hot water virtually free…and have done since the system paid for itself many years ago.

And our savings continue to rise even more each time energy costs rise :).

Unless you’re heating your water using renewable energy like solar, water heating is a big part of your footprint on our planet…and on your hip pocket.  In Australia, water heating accounted for about ¼ of each home’s energy consumption and greenhouse gas emissions in 2008.

That’s why many experts agree that a solar hot water system is the best investment you can make to reducing your energy consumption and costs.


  • If you’re not using a solar hot water system, how about making the change?  There’s no time like the present, with energy prices on the rise.  And, if you’re in the southern hemisphere, summer’s just around the corner.  (Hint: be careful with any booster your system uses, to ensure you can control when it is used…so you don’t get a surprise with your energy consumption going UP!)
  • If you are using solar hot water, what is your experience?  If it has manual boosting, how are you managing individual users’ behaviour?

Share your experience in the Reply box below.

Till next time…be gentle to yourself and our world!