Green Building Forum - Solar thermal costs - and worth it?

Solar thermal costs - and worth it?

smudger — Fri, 10 Sep 2021 19:09:38 +0100

We already have pv. Thinking about installing solar thermal. What are the typical costs for a 4 sqm system? We already have a solar ready cylinder linked to gshp. Need to make decision soon as RHI payments are being switched off and suppliers are busy do will probably have to commit in the next month.

(Whatâ€™s also off outing is seeing the number of posts offering removed systems)

Solar thermal costs - and worth it?

philedge — Fri, 10 Sep 2021 19:36:31 +0100

I dont know how it fares for space heating but our 30 tube system has done 99% of our DHW for 6 months of the year since 2006. Contributes to DHW for the rest of the year. Worked faultlessly throughout with a fluid change after 10 years. Self installed with no RHI and associated inflated prices!!

Solar thermal costs - and worth it?

Jeff B — Fri, 10 Sep 2021 19:47:56 +0100

Posted By: philedgeI dont know how it fares for space heating but our 30 tube system has done 99% of our DHW for 6 months of the year since 2006. Contributes to DHW for the rest of the year. Worked faultlessly throughout with a fluid change after 10 years. Self installed with no RHI and associated inflated prices!!

More or less ditto here. Filsol flat-plate system, 14 years old, so pre-RHI. Provides practically all DHW from May to September. Very little maintenance required, just an occasional check on the pH of the glycol solution. If I had my time over I would have opted for an Immersun type device I think, mainly because it is one less plumbing system to think about! Don't know if such things were available back in 2007?

Solar thermal costs - and worth it?

jms452 — Fri, 10 Sep 2021 19:56:09 +0100

Posted By: Jeff BIf I had my time over I would have opted for an Immersun type device I think, mainly because it is one less plumbing system to think about! Don't know if such things were available back in 2007?

Proportional solar diverters weren't really available then and in 2007 the PV would have been really pricey - like 4kW Â£20k pricey.

At the time the smart money would have been on solar thermal (probably DIY)

Solar thermal costs - and worth it?

djh — Fri, 10 Sep 2021 20:16:08 +0100

Posted By: smudgerWhatâ€™s also off outing is seeing the number of posts offering removed systems

Not being in the market for such things, I haven't seen those. Why are people removing them?

If you already have PV, do you also have a diverter? How much of your hot water do you get from that? What is the purpose of the proposed solar thermal? etc etc. More information please!

Solar thermal costs - and worth it?

Ed Davies — Fri, 10 Sep 2021 22:05:49 +0100

With the demise of Navitron the source of DIY solar-thermal kit which springs to mind would be:

https://www.bimblesolar.com/extras/thermal

to give you some idea of the cost of the hardware hence how much of any quotes are for installation labour and MCS â€œtaxâ€.

Solar thermal costs - and worth it?

revor — Sun, 12 Sep 2021 17:02:01 +0100

My system been in use for 2 years flat panel Velux to match roof windows. System no longer available in UK. DIY job but had roofers help me put panels in place as were heavy. Panels been in for about 7years before commissioning build taken a long time. Get all our hot water from Beginning of May to end September last year topped up on about 2 occasions with 10 min burn of gas boiler. This year not needed to use gas. As the TS also feeds the ufh will get some contribution to that but probably v small. Had quite a bit of help from this forum when I was setting up the controls the programmer was quite difficult to understand without the guidance from here as to how the control system works. Cost was about Â£2000 for the bits. 5sqM
Have heard horror stories of poorly performing systems but think that is down to quality of install and setting up. Have installed solar PV this year and do not put surplus generation to the TS as have battery to store the excess solar and any bits left goes as export.

Solar thermal costs - and worth it?

smudger — Sun, 12 Sep 2021 20:30:01 +0100

Thanks for the feedback everyone

Solar thermal costs - and worth it?

DavidND — Sat, 16 Oct 2021 12:24:46 +0100

The single reason most systems that are removed are removed is ignorance. By that I mean the poor people who paid a premium for new builds with systems installed almost exclusively have no idea whatsoever what it is, how it works or how to maintain it. No surprises from home builders there then!

As a direct consequence most systems are never maintained. Homeowners have no idea what they are looking at when they look at the controller and eventually many systems simply rot out.

If anyone is interested, probably not on this forum TBF I've produced a PDF with extremely simply non technical instructions on how to tell if your system is working or needs maintenance.

Truth is, Navitron was formed to simply exploit the Govt grants in force at the time. The guys who have taken over, doing it because its the right thing to do and all that, are called Ruland Renewables. If you're in Yorkshire tho, I'll help.

Solar thermal costs - and worth it?

djh — Sat, 16 Oct 2021 14:52:45 +0100

DavidND said "The guys who have taken over, doing it because its the right thing to do and all that, are called Ruland Renewables."

I take it you meant https://www.rutlandrenewables.co.uk/ ?

I'd be interested to look at your PDF if it is accessible?

Solar thermal costs - and worth it?

Jeff B — Sat, 16 Oct 2021 18:16:25 +0100

Posted By: djhDavidND said "The guys who have taken over, doing it because its the right thing to do and all that, are called Ruland Renewables."

I take it you meant https://www.rutlandrenewables.co.uk/?

I'd be interested to look at your PDF if it is accessible?

Me too please!

Solar thermal costs - and worth it?

Jonti — Sat, 16 Oct 2021 19:00:44 +0100

Posted By: DavidND

If anyone is interested, probably not on this forum TBF I've produced a PDF with extremely simply non technical instructions on how to tell if your system is working or needs maintenance.

Could you put a link to your PDF or perhaps post it on here.

Solar thermal costs - and worth it?

BenM — Tue, 19 Oct 2021 11:53:07 +0100

We had ours installed under the Green Homes Grant in June this year. Total cost was Â£5,250, of which we paid 1/3 (i.e. Â£1,750). We already had a thermal store with a solar connection, so they were just installing the panels and all the stuff that goes with that. The system is 4m2, and that's made up of two flat plate panels, which feed into the tank in the loft.

We've been really happy with it so far. It does nearly all the hot water June to September / early October. It was amazing how hot it gets the tank, so you don't need it to be super hot every day, as the tank is well insulated and carries the temps into the next day.

We've barely noticed it's there, to be honest, other than using very little gas over the summer and late autumn.

Solar thermal costs - and worth it?

revor — Tue, 19 Oct 2021 12:59:24 +0100

Posted By: BenMWe had ours installed under the Green Homes Grant in June this year. Total cost was Â£5,250, of which we paid 1/3 (i.e. Â£1,750). We already had a thermal store with a solar connection, so they were just installing the panels and all the stuff that goes with that.

Nice bit of profit there for the installer and a good buy for yourself.

Solar thermal costs - and worth it?

RobL — Tue, 19 Oct 2021 13:17:00 +0100

Why on earth was PV not covered by the green homes grant ? It just makes more sense now than solar thermal - can usually make plenty of hot water, anything spare going to the grid. We have both by the way, pro install of PV, diy solar thermal.

Agree it makes sense for an individual to go for thermal now, due to the grant skewing things.

Solar thermal costs - and worth it?

revor — Tue, 19 Oct 2021 14:31:12 +0100

Far better for the PV to go into a battery so you can use when sun is not shinning. Far more flexible use. There were times during the summer we could go for a week without using the grid or maybe 1 Kwh. Averaging 98% self sufficiency. Different picture this week and the battery just ticking over and most coming from grid, even so self sufficiency so far since May been 90%. Will get worse as days get shorter. But get one sunny day and get 2 days free electric.

Solar thermal costs - and worth it?

BenM — Tue, 19 Oct 2021 14:33:42 +0100

Posted By: revor
Posted By: BenMWe had ours installed under the Green Homes Grant in June this year. Total cost was Â£5,250, of which we paid 1/3 (i.e. Â£1,750). We already had a thermal store with a solar connection, so they were just installing the panels and all the stuff that goes with that.

Nice bit of profit there for the installer and a good buy for yourself.

Yeah, I think everyone did pretty well out of it. Friend of mine, who's keen on renewables, was a bit taken aback by what the installer was charging. However, I think we did ok for what we paid. Definitely recommend solar thermal for anyone who is interested. We are lucky that we have a south facing roof with no tree cover and the TS was in place just waiting for the solar connection.