Solar Hot Water

[Tim86]

I just installed a 315L solar hot water system at one of my IP's. This is the system: http://www.simplysolar.com.au/images/content/dux_hot_water.jpg

It cost $1500 for the system supplied. Then it was another $1000 for all the copper pipe, supplies to make a reverse pitch mounting frame, and a few other bits and pieces. So $2500 all up. It cost a bit more because we had to run the system to the granny flat as well as the house (40m of pipe to run to the flat) and used up another 35m of pipe for the rest of the setup.

Seems to be working well, takes about 30-40 seconds to get hot water into the granny flat, and hot water within 5-10 seconds in the main house.

Previous power bills have been huge, 5000kw used last quarter. I'm hoping to save about $700 per quarter with the new setup.

By the way I get stuck with the power bills due to it being a shared house with bills included in the rent. Which is why it's worthwhile me putting this setup in a rental. The savings should cover the cost of the system within 1 year.

Does anyone have any idea how much a job like this would normally cost? To supply a 315L system, rip out 2 old hot water systems, run pipe to a granny flat and a house (75m all up), dig a 20m trench to run the pipe, build a steel frame to mount the panels on the roof, wire in the system, plumb everything in?

 

[womble66]

Seems to be cheap given the extra material/work as I had a 400L of the same ECOSMART (DUX) 2 panel system installed and it was close to $3800 less rebates so $2000 out of pocket.

http://www.ecosmart.com.au/products/electric-boosted-solar.html
GWA Group own both DUX and ECOSMART so its the same products just labelled differently.

As for saving $$$ I would say no given your probably going to still run out of water and as its still probably connected to electric boost your still going to be paying for HW, maybe even more if its not on off-peak.

I had a "mate" wire mine to the existing off-peak circuit and install a breaker switch so I could isolate (turn it off) at the tank and found even with this setup I saved on AVE only $60 per 1/4 on off-peak.

For me I think this type of solar HWS is just not worth it and next time I would have looked at an evacuated tube system. Luckily in my new home I have NG HWS so no need now and will swap that to an instantaneous system when required.

 

[Tim86]

Seems to be cheap given the extra material/work as I had a 400L of the same ECOSMART (DUX) 2 panel system installed and it was close to $3800 less rebates so $2000 out of pocket.

http://www.ecosmart.com.au/products/electric-boosted-solar.html
GWA Group own both DUX and ECOSMART so its the same products just labelled differently.

As for saving $$$ I would say no given your probably going to still run out of water and as its still probably connected to electric boost your still going to be paying for HW, maybe even more if its not on off-peak.

I had a "mate" wire mine to the existing off-peak circuit and install a breaker switch so I could isolate (turn it off) at the tank and found even with this setup I saved on AVE only $60 per 1/4 on off-peak.

For me I think this type of solar HWS is just not worth it and next time I would have looked at an evacuated tube system. Luckily in my new home I have NG HWS so no need now and will swap that to an instantaneous system when required.

Why would you run out of hot water? A 315L tank should be fine for 5 people shouldn't it?

The electric boost is hooked up to the switchboard and I've just left it off as it got hot enough without it. I'm yet to check in with the housemates how it's been performing at night.

I think it will still save a lot of money even if I have to put it on electric boost for a couple hrs per day. The previous setup consisted of 2 smaller electric hot water systems that had to be on constantly because they were too small to only be put on off peak as they would have run out of hot water. Which meant that my 1.5Kw electric solar system wasn't able to produce any excess during the day so I didn't get the 50cent per kw feed in tariff as all that energy got used by the inefficient on peak hot water systems.

As the previous setup was so inefficient (2 hot water systems instead of 1, and they were robbing me of my solar electricity feed in tarrifs, and they were on peak) I think this should still save me money, even if the solar doesn't work at all and I have to run it as a normal hot water system.

But I'll let you know how it goes.

Previous bill was $1200, I'll post how much the next bill is

 

[Tim86]

Just checked the temp of the hot water system, I haven't put the booster element on and the water in the tank is still 58 degrees and the collectors are 65 degrees. And that's at 10:30am on a rainy day with the sun covered by cloud.

Perfect temp in the tank would be 60-65 degrees (to prevent bacteria growth) so I'm pretty happy with 58 degrees given the bad weather. You only need 42 degrees for a shower, so it should be more than enough.

 

[womble66]

Why would you run out of hot water? A 315L tank should be fine for 5 people shouldn't it?

I have no idea but I went from a 250L std off-peak system to a 400L solar and when I turned my booster off I got luke warm water quite often and run out on occasions. But the depends on location and usage patterns but I found the DUX an under performing system with its 2 panels. With being in QLD your system would work more efficiently than mine due to the temp variation. My main issues were in the colder months not now in spring/summer.

Which meant that my 1.5Kw electric solar system wasn't able to produce any excess during the day so I didn't get the 50cent per kw feed in tariff as all that energy got used by the inefficient on peak hot water systems.

This will definitely change your savings if most of your daytime kw consumption was the HWS. If you can export more then the savings will be greater but my savings were based purely on the solar HWS not taking into account any solar PV system benefits.

You should save money and good luck with the DUX as your situation may be different to mine.

 

[Tim86]

I had a look at some reviews for the Dux system, lots and lots of bad reviews. I did look for reviews for the conenergy system before buying, but found no reviews, obviously because it was a rebranded Dux (probably because of the **** reputation Dux has).

Looks like lots and lots of issues with the system. Although the encouraging thing is that most of the faults seem to be due to bad installation. Also a lot of the faults seem to be because it can't handle frost. So being in qld where our winter is like NSW's summer, I should hopefully avoid that issue. I installed it all correctly and have a 5 year warranty so should be all good. A lot of people complained because the 5 year warranty didn't cover labour, but I can replace the solar panels myself in about 30 mins so I won't have to fork out $400 like some people did due to rip off plumbers.

The valves, thermostat, and pump are the things I'm worried about. They only have a 2 year warranty with simply solar and seem to fail around that time according to some people. Shall see how it goes, hopefully I'll be lucky and won't have any problems lol but in my experience when things can go wrong...