Are you all pleased with your solar panels for hot water heating

rolion

championc wrote: »

On this basis, if it never goes over 100C, does it ever need replacement at all ?

I advise,non profesional,to replace it once every few years to get the best results, as i guess is losing the chemical properties of the liquid.

If an analogy is permitted, same with the car oil engine :after a while it gets "dirty", replace it and the engine runs smoother.

josip

rolion wrote: »

I advise,non profesional,to replace it once every few years to get the best results, as i guess is losing the chemical properties of the liquid.

If an analogy is permitted, same with the car oil engine :after a while it gets "dirty", replace it and the engine runs smoother.

Is the oil analogy correct?
Wouldn't the car water/coolant be a better analogy than oil?

unkel

josip wrote: »

Is the oil analogy correct?
Wouldn't the car water/coolant be a better analogy than oil?

I'd say so. And coolant in a car has to do a lot more work than the coolant in a solar tube system that can not go over 135C. Recommended replacement for coolant in a car is 3 years alright. I'll ask my Kingspan certified installers when I get a chance, to see what is the official recommendation.

Shefwedfan

I guess we cannot ask for company recommendation on this thread or any thread on boards?

beertons

Shefwedfan wrote: »

I guess we cannot ask for company recommendation on this thread or any thread on boards?

That depends. What exactly are you looking for?

Shefwedfan

beertons wrote: »

That depends. What exactly are you looking for?

Solar Thermal installation companies. I wont be doing a solo job.

I did try a few companies but would be unsure if any good

unkel

Mine was done by AEI

Linky


They are a Kingspan accredited installer. They did a very clean and professional job, working around a few issues in my install and sorting them pro-actively (without charging more than agreed upfront). I recommend them.

rolion

Shefwedfan wrote: »

I guess we cannot ask for company recommendation on this thread or any thread on boards?

My friendly advice is first to get used and then apply for the SEAI grant.
During the application, you will need to chose an accredited installer that has the company listed on the SEAI database.

From there, you can buy the system yourself from any DIY building shops or ask the installer to do all the install themselves.

I can recommend my installer via PM.

Search for three quotes that are local to you and ask for references .

Good luck...

NIMAN

I got to thinking about a solar hot water system recently, and got an estimate of just over €5k from AEI on the link Unkel provided above.
Does that sound like a reasonable figure?

Info:
House SSE facing
Family of 5
Built 2001



Is there any costs afterwards that I'd need to consider? I see replacement anti-freeze mentioned every 2-3yrs, how much does that cost?

How long will the system last? Will it still be heating as much water in say 20yrs time?

John.G

Can you give a rough scope of your proposed installation, tubes/panels, number of tubes/make, panel size.... M2 etc.

josip

NIMAN wrote: »

I got to thinking about a solar hot water system recently, and got an estimate of just over €5k from AEI on the link Unkel provided above.
Does that sound like a reasonable figure?

Info:
House SSE facing
Family of 5
Built 2001



Is there any costs afterwards that I'd need to consider? I see replacement anti-freeze mentioned every 2-3yrs, how much does that cost?

How long will the system last? Will it still be heating as much water in say 20yrs time?

I don't know anything about recent prices but I can't imagine you getting a system for much less than €5k.
FWIW, we paid €3.1 after grant in 2010 for an 18 tube system.
In the past we have paid €200-€300 for anti-freeze replacement, but the most of that was the plumber cost.
Since we added a heat dump to the system, the fluid hasn't superheated and we haven't had to replace it in the last few years.

Assuming your system has a heat dump in the initial design, it should still be functioning well after 20 years.

unkel

You don't need a heat dump in a vented system like the Kingspan, the temps never go high and you don't need any service / coolant replacement for at least 5 years.

I paid €4,700 for a 40tube Kingspan system 5 years ago, but that was a good few hundred under the going rate and it involved some extras like installing a massive cylinder in the hot press and moving my waterpump for my pumped water (cold and hot)

Since then, PV has become a lot cheaper and now has a very generous install subsidy too, neither was the case 5 years ago. If I had to do it again now, I would not go solar thermal, but I would go very large solar PV - the bigger the better, minimum 6kwp (with diverter)

Patmwgs

Solar thermal has a bit more maintenance with the odd tube and liquid replacement. On the plus side you dont need as much roof space for it. With pv now coming down quite abit in cost in the last 10 years it is getting more realistic for install. If i was thinking of either install i would go pv as it will provide hot water for the same time of year as the solar thermal panels.
If you are going solar thermal i would advise a heat dump. Especially when on holidays, if we ever get any.

unkel

Patmwgs wrote: »

If you are going solar thermal i would advise a heat dump. Especially when on holidays, if we ever get any.

See my post, you don't need a heat dump with systems like above Kingspan.

Patmwgs

Kingspan panels must work at a lower temperature, but alot of other panels can reach very high temperatures and a heat dump does help save the system from stagnating. It would also depend on how many panels are installed versus the size of your storage tank. If for instance you are not at home for a few days and your tank has reached its maximum temperature, then the sytem will stagnate and over time will cause damage.

John.G

Patmwgs wrote: »

Kingspan panels must work at a lower temperature, but alot of other panels can reach very high temperatures and a heat dump does help save the system from stagnating. It would also depend on how many panels are installed versus the size of your storage tank. If for instance you are not at home for a few days and your tank has reached its maximum temperature, then the sytem will stagnate and over time will cause damage.

Some E.tubes inc Kingspan? can reach 250C on stagnation but the HP400 has a snap disc that shuts off heat transfer at 90C so presumably the fluid inside doesn't rise any higher, I never see much about these even though they are available for a good few years now, I have 2X F.Plate with a 150 litre HW cylinder with a TMV set to 60C, the max temperature I have ever seen the cylinder is 76C even with little or no usage but I can dump heat via the second coil and a few rads if needs be, I have never changed the thermal fluid in 10 years and performance is same as day 1.

Patmwgs

Hi john, i have the calpak tubes and i have it dumping to heating system when it reaches the cut off temperature. 4x panels with 500 litre tank. I had some early problems with tube breakage on their original panels but they sent me replacement panels of newer design so no problems since.

Rechuchote

What about a similar thread for PV panels - have people found them good value…

mitresize5

Id be very interested in this.

Gathering quotes at the minute and sales men/women ranging in promises from providing 30% saving on yearly bills to never having to pay for electricity again 😀

MAULBROOK

https://www.boards.ie/discussion/comment/118558360#Comment_118558360

https://www.boards.ie/discussion/comment/118560845#Comment_118560845

https://www.boards.ie/discussion/2058219537/domestic-solar-pv-quotes-2022#latest

MAULBROOK

https://www.boards.ie/discussion/comment/118560845#Comment_118560845

I can send you the name of the Solar PV company if you want.

The company I used is a BS free zone.

Shoog

I did a DIY install out in the west of Ireland, two big panels and two DIY panels with multiple staged tanks for storage.

I must say I have been disappointed, but because I only spent about €2K I am not that annoyed. If I had have had a professional install I would be mighty gutted. The issue we have is that where we are we are surrounded on three sides by mountains which generate clouds which ever way the wind is blowing. This gives us 50-100% cloud cover all year round. The upshot is that from October to March we really never see the panels heat enough to generate any heated water. In the rest of the year we get about 50% preheat most of the time and if the sky clears we get all our hot water - but in the 10 years we have had them they typically only work for all of our hot water for a month or two. They are capable of doing the job and if we were east of the Shannon they would likely double or triple their yearly output.

I wouldn't do it again if I knew then what I know now. its not just my opinion since I have a friend who lives a mile away and he has a similar opinion. I would go PV if I was starting out as it will be cheaper (all that extra plumbing is at least half of the cost) and will produce a useful amount of heat even in winter when there is cloud and short daylight. Why - because they do not have a cutin therreeshhold so will take advantage of even dull light to produce a trickle charge something solar thermal just wont do.

Really the most critical factor is location and average cloud cover. if you live in a wet cloudy location forget it - save your money.

thebluesideburn

I've a complicated dilemma so looking for any advice....

I ran out of budget when doing my house and want to do solar now. The complication is I already have a 500L Solar Thermal Tank with pipes to the attic and the house is 95% underfloor heating so would run at a lower temperature. (Gas boiler is main source.)

I've a large flat roof but a bit of a tree shade concern but most people suggesting PV with Eddi but given I have some of the core bits in place would I mad not to do some Solar Thermal on the flat roof? - I can do PV on the pitch roof with less shade.

I was thinking PV with battery. The boiler is new due to an emergency so again my gut is against Heat Pump for the moment which would mean changing the tank.

Any thoughts appreciated. Dublin based.

graememk

https://www.boards.ie/discussion/comment/121217928#Comment_121217928

What do you want the solar to do? Is that solar thermal tank domestic hot water or a large buffer tank connected to the underfloor heating?

thebluesideburn

https://www.boards.ie/discussion/comment/121218183#Comment_121218183

Hi. Thanks. It is a dual coil hot water tank. It supplies underfloor via a mixer. It is a Telford Tempest Indirect Twin Coil Solar.  

thebluesideburn

https://www.boards.ie/discussion/comment/121218183#Comment_121218183

To your first question. I'm trying to understand the best way to go. With tank there should I do solar thermal or do I just go PV and aim for heat pump down the road. Current tank is not good for heat pump.