Our new solar hot water system- it’s a little bit different!
After moving into the new house in early July, we’ve been enjoying hot water for a whole week now! It’s amazing what a difference it makes to your life and how much we take it for granted.
The house we bought had a hot water system but it was totally stuffed and unusable. We wanted a new system that didn’t depend on fossil fuels, which meant we were looking at solar or a heat pump. Heat pumps run permanently on electricity, even though they don’t use much of it, and feedback from others was that their lifespan barely exceeds warranty. So, solar seemed the logical choice.
Researching solar hot water systems took quite a long time but I think I got the right product in the end. I am always trying to find the least hi-tech solution for anything as technology is fantastic until it breaks down! I have seen a lot of solar water systems out there with more microchips than my computer. I also wanted a system that could be easily hooked up to a combustion stove to provide hot water on cloudy winter days. The last point may sound simple, however most modern systems make it hard: their solutions are very expensive and even more reliant on technology to add extra heat from a combustion stove. So look out if that’s what you want to set up.
Our choice of system (and why)
The system we bought is all stainless steel and uses no pumps. The system also uses evacuated tubes to capture the sun rather than a flat plate panel commonly seen on older models. Evacuated tubes are much more commonly used these days for a number of reasons:
- They are like light bulbs in the way they can be individually replaced if one breaks, and they are only made in a few different sizes so they can be swapped from brand to brand.
- They capture full sunlight up to 90 degrees east or west of north or (in simpler terms) from sunrise to sunset. Flat plate collectors only operate at optimum at midday.
- Some reports say evacuated tubes are 168% more efficient than flat plate collectors in Australian conditions. Other reports say it’s more like 30-80%. I have never owned or operated a flat plate solar hot water system, so I cannot comment. All I can say is that on a sunny winter’s day (in the Blue Mountains NSW) that the system is reaching more than 80 degrees Celsius by 3pm (I can test this by turning on the electric override and it does not come on because the thermostat is set at 80).
Installation (with a little help from my friends)
Putting this system together took a lot of effort of my part and I felt like giving up a few times. I had to buy a kit from a dealer in Queensland who shipped it to Sydney. I had to collect it with my ute and put the frame together myself. I was going to put it on the roof myself but I got nervous wondering if the roof could hold the 400kg weight so I got a roofer to put the frame up and confirm that it was strong enough. It was all good and the roof was strong enough but I am not a builder and a roof collapsing is an expensive mistake. We had a few issues with the tiles anyway and he took care of them too all for a really good price. His name is Dave and his number is 0405 912 691. He is a licensed roofer in the Blue Mountains.
My friend Jordan and I then mounted the tank and the evacuated tubes on the roof which was a relatively easy task. Finding a plumber that was willing to plumb the system was another matter. I think I called at least 6 plumbers and although this system is incredibly simple to plumb, they were not willing to do it. I am not going to waste time bagging out the plumbers that didn’t return calls or that showed up to give quotes then disappeared never to be heard from again, but I will tell you who was keen (even excited) to do it. Brendon McClement in Hazelbrook Tel: 0417 264 678. Brendon has lots of experience installing solar systems as well as wetbacks/water jackets to combustion stoves. I think I have finally found a plumber to help me with my strange future experiments!
Some final thoughts
All up, our system cost about $4000 installed. The closest comparison price I found was $5500 (for a flatplate collector- which I didn’t actually want). We had a few teething problems including a broken water tube (my fault) but all in all it’s awesome. Solar hot water is not like having on-demand hot water reheating all the time like we have had in the past. We have an almost endless amount of hot water for the evening to wash the dishes, shower or bathe. In the morning there is enough hot water to again wash dishes etc. but I have not yet tried morning showers and I suspect it would run cool. Fortunately, we are evening showering people anyway. We can, of course, solve this by running the electric thermostat overnight to top the system back up, but that seems to defeat the purpose of having solar hot water when all that needs to be done is a little bit of shuffling of our water use habits. For us, we’re more than happy to be a little bit flexible with our water habits if it means we can reduce our electricity consumption by 50%. If you’re similarly concerned about the rising costs of power (some are predicting a price doubling in the next 5 years) then solar hot water might be a good option for your next system.