Solar Hot Water Heaters

[cassgazz]

Well, just had our Electric Hot Water Service crap itself, so getting prices for replacements.

We had thought about going solar, and got a quote for $5k. This includes a roof mounted SOLARHART system, that has the internal glycol to prevent freezing, and also an over-temp protection. System is gas boosted, so heats using bottled gas, between the solar system and taps, if the water is not up to temperature.

Just wondering if anyone has had any experience with solar hot water systems, and your opinions, including the following -

1. Does it save as much $$$ as what they claim - we have been told around $400 a quarter (Currently 400 litre electric system)
2. Do you find the water gets hot enough from the solar system, or is the booster always working?
3. Would you install another one?
4. Anything else you can think of.

Thanks,
Gary

[Burnsy]

We are in WA so temp/weather is different.  Love our solar and the booster is isolated/off for at least 6 months a year. Ours is a Beasley, went with it purey because it was cheaper than solarhart and came with a staniless tank as standard.

Solar is great but don't get gas boosted if you are on bottled gas, it is to expensive and will never pay back the additional cost of the gas boosting.  Electrical boosting is via an element and thermostat that I was told all units come fitted with as standard anyway and is a better option if you are on bottled gas.

[D4D]

1. We have a 10 year old electric off-peak boosted SolarHart, tank and solar all in one on the roof. I turn off the booster around Nov and back on end of March, so yeah it does save $.
2. Yep too hot in fact, ours was installed without a temp limiter, our plumber says it should be colder to be safe
3. I would install one again however just to get it off the roof I may go a continuous gas, see below.
4. We have a leak in the roof at the moment that has soaked through the plaster. It is the join from the HWS to the main hot water outlet. We need to cut the plaster out to get to it to fix it and then repair the plaster.

[Pirate_Pete]

I have a 30 tube Solar Lord system hooked up to a 315l (I think) cylinder in Tassie & I save about $300 a quarter.

In my opinion you need to think of 2  things when getting a system
     1 get the biggest cylinder you can get to save as much heat when the sun is out.
     2 set the collector up to get the most out of the winter sun (most people will tell you that you want to set it up at the same angle as your latitude but that is only the average position you need to be at a right angle to the sun in the winter monts to get the most out of hot water)

[TOPNDR]

Friends & colleagues in Cairns & Kuranda have solar HWS and are very happy with them but I couldn't quantify the savings.

We've installed 5 kWH solar systems on two properties.  In the first billing period of one, our bill indicates were $500+ in credit.  We're so happy with this that we'll probably go solar when the HWS poops itself.

[cassgazz]

Thanks for the replies so far.

The system we were quoted was a 220L tank situated on the roof. Plenty of room up there to keep an eye on things, so not to concerned about access.
One thing I had considered, was eventually getting solar POWER connected, so will be getting info on an electric booster.
We do not have gas installed at all, but the installer planned on using 2 gas bottles. I was not too keen on this, as it was just another cosat.

D4D, sounds good. Should be roughly the same down this way. 4 months with no power consumption for water heating sounds good.

Pirate_Pete, we have a large roof, with the majority of it being North facing. With considering eventually getting solar panels, I have been keeping an eye on the sun position, and it seems to get quite a bit of sun for most of the day. Would that still be suitable do you think in winter?


Cheers,
Gary

[Burnsy]

One thing I had considered, was eventually getting solar POWER connected, so will be getting info on an electric booster.
We do not have gas installed at all, but the installer planned on using 2 gas bottles. I was not too keen on this, as it was just another cosat.

Definitely give the gas a miss, if you have off peak power you will save a fair bit by heating in the early hours of the morning before morning showers then just boosting again at around 4pm to top off the temp after the day.  Ask the electrician to install a pin timer in the electrial fuse box next to the HWS breaker and then you can control when it goes on and off.  There is no use say having the electric booster cut in and start heating water at 1pm in the arvo after you have just washed some clothes or something if the sun is out.

We use the pin timer for the seasonal changes and have it on permanetly over winter.  No noticable difference in our power consumption really as this is the only electrical heating in the house, wood fire does the rest and we run evaporative AC over summer so kind of cancels each other out.

[Sixtys Guy]

Gas backup is good, even for LPG as it will only boost the water as required. For example if the hot water in the cylinder is at say 45 degrees, then the booster will heat the water up to 60 (depends on what the booster is set at, depends on the manufacturer). If the hot water in the cylinder is at 60 or above the gas booster doesn't come on. It also ensures that any nasties in the cylinder (legionella) are removed by the booster.

[Pirate_Pete]

Thanks for the replies so far.

Pirate_Pete, we have a large roof, with the majority of it being North facing. With considering eventually getting solar panels, I have been keeping an eye on the sun position, and it seems to get quite a bit of sun for most of the day. Would that still be suitable do you think in winter?


Cheers,
Gary

Yep North is the best for every season. 

If you are thinking of fitting electric panels in the future talk to some one now to make sure you don't get the water unit in the wrong spot.

Electric panels are best setup at the angle that puts them at a right angle to the summers sun so you collect the most power when there is the most sun.

[D4D]

Hmmm ours faces due west but it has no trees or other obstacles to shade it so it gets sun all day.

[PAC1977]

Hey cassgazz,

We have one and are in Traralgon as well (although ours in Natural Gas). Works really well, panel's face north and seem to do a good job. My only gripe with the system is that sometimes the water gets a bit hot so we have to adjust where we would normally have the tap.

Paul

[Pirate_Pete]

Hey cassgazz,

We have one and are in Traralgon as well (although ours in Natural Gas). Works really well, panel's face north and seem to do a good job. My only gripe with the system is that sometimes the water gets a bit hot so we have to adjust where we would normally have the tap.

Paul

My younger bro is the plumber who fitted mine & the put in a mixer to "cool" the water down to 50c as he said it was required where the hot water went to a bath, hand basin or shower so people don't gets burnt. Kitchens & laundries don't require the mixed water but as my house was only plumbed with hot & cold water & no mixed I have 50c at all my hot taps.

[Sixtys Guy]

A tempering valve is required for the bathroom areas and these are usually supplied with the unit. For those worried about the hot water being too hot in the kitchen and laundry, you can ask your installer for a Primary Temperature Control Valve, which limits the hot water to these areas to 60 degrees.

[cassgazz]

Thanks for the replies. We have decided to give the solar a miss, and get the old one repaired.

Did quite a bit more research, and ended up with more negatives than positives - especially poor service when it comes to repairs.
May look at it in the future when the prices become a bit more realistic, and i can work out the best brand to go with.

[Hairs]

Hi Gary,
Had installed about three years ago a Solarhart, about 300lt.
There is the 5 of us, 2A, 3Kids, two eldest are girl teenagers 
We have our boast wired to a switch in the meter box, the old electric hot water services switch.
On over cast days we have to flick the switch, most days tho are enough to heat it well.
Winter here on the north Coast of NSW(Lawrence), can get below 0 sometimes and cloud cover can effect performance to the point were we need to boast it a good hour before we all need to use it..
The last two years in winter the pipes have frozen, so a shower in the morning is out of the question, we all use the hot water of a night now.
It was trial by error to work out how long each of us can use the hot water,
We were lucky enough that we got a fair chunk of ours through rebates.
We've worked it out that it saves us about $140 a quarter on our electricity bill.
Although not the same as having electric heated the water, it does us fine.
As mentioned, it took a bit to work with it, but we are happy we have gone this way.
Hope this is of some help.

[uncyspam]

we have a solarhart 300l on our place and it works ok - im a bit dissapointed at how much electrickery it uses during winter though.

when we build our new house, ill be looking at an Evacuated Tube system instead, apparently much more efficient in cooler climates.

http://www.energymatters.com.au/solar-hot-water-evacuated-tubes-c-162_375.html

[jnik]

This thread prompted me to look into PV/T-hybrid panels (photo-voltaic/thermal) ... generate electricity and heat water (or heat/cool the home) at the same time.

These units look quite innovative: http://www.solarus.se/hybrid.html

They expose both sides of the solar wafers to the suns rays (direct sunlight from above and concentrated reflected sunlight from below).

Three times the power generated per wafer, and heats water too!

The optics are set to direct concentrated sunlight onto the lower side of the wafers no matter the angle of the sun.

Apparently they're cheaper per watt (because they're three times as efficient) as PV panels.

There are other PV/T panels, but this is the only one I've found that uses both sides of the wafers.

Unfortunately I haven't found anything like this locally ... :-(

[Jenko67]

we have had solar with electric boost and never used the booster as we always had enough hot water... we are in SEQ though...

We have solar with gas backup now and very rarely see the gas have to heat the water... we had ours installed when we built the houses...highly recommended..