Green Building Forum - Solar Panels (for heating water) - why do it? Tue, 19 Dec 2023 06:03:51 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210403#Comment_210403 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210403#Comment_210403 Sat, 04 Oct 2014 16:08:42 +0100 SteamyTea Posted By: jamesingramLike a trombe (thermosiphon) wall ?That is how I would do it.
Trouble is that I don't think there is that much energy to be got. Easy enough to do the sums though.
Probably find for drying timber just moving air though it is as affect as anything. How 'windchill' works.
It is all down the physics not so much the energy source.]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210406#Comment_210406 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210406#Comment_210406 Sat, 04 Oct 2014 17:50:05 +0100 renewablejohn Posted By: SteamyTea
Posted By: jamesingramLike a trombe (thermosiphon) wall ?
That is how I would do it.
Trouble is that I don't think there is that much energy to be got. Easy enough to do the sums though.
Probably find for drying timber just moving air though it is as affect as anything. How 'windchill' works.
It is all down the physics not so much the energy source.

I know the technology works as I visited a site while in Austria using the system for drying woodchip but I cannot remember whether it had the PV panels on the top. Apparently there is a big new M & S distribution centre near Leeds fitted with it on the vertical south aspect but not with the PV panels fitted.]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210421#Comment_210421 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210421#Comment_210421 Sat, 04 Oct 2014 22:56:51 +0100 atomicbisf
I've been looking into them for our roof as it will only fit 12 panels of an average sort of size, so 12x330W seems the way to go.

Ed]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210425#Comment_210425 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210425#Comment_210425 Sun, 05 Oct 2014 08:08:51 +0100 SteamyTea Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210429#Comment_210429 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210429#Comment_210429 Sun, 05 Oct 2014 09:25:16 +0100 jamesingram Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210431#Comment_210431 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210431#Comment_210431 Sun, 05 Oct 2014 10:33:39 +0100 atomicbisf
Hopefully It'll drop a bit more by next year when hopefully we can have it installed with the new roof covering. I am still dubious though of whether using grid-tied solar PV for water heating can be justified on environmental grounds in most cases.

Ed]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210437#Comment_210437 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210437#Comment_210437 Sun, 05 Oct 2014 11:05:26 +0100 SteamyTea
I shall have to ask around, I know a few people in the industry that may be able to help.

My main point about DIYing it is that if they cut the FITs by much more then it is not worth going down the MCS route (was set up to reduce the payments and make the industry self reliant after all).
Just have to find out if it is possible to get paid for exports though a smart meter and what the rates will be.
If I can generate at 7p/kWh then it is a no brainer, at 14p, assume the kit costs £7000 installed and I can offset 2.5MWh/year then it is marginal. And that would assume staying in the house for the next 20 years, or taking the stuff to the next place (which is an advantage of DIYing it.]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210438#Comment_210438 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210438#Comment_210438 Sun, 05 Oct 2014 11:14:48 +0100 Ed Davies Posted By: jamesingramLike a trombe (thermosiphon) wall ?Note, not all thermosiphon walls are Trombe walls - a Trombe wall necessarily has high thermal mass whereas other types of thermosiphon walls can be thermally lightweight, which might be more appropriate in the case of cooling PV where you want to move the heat away from the scene as promptly as possible.]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210596#Comment_210596 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210596#Comment_210596 Mon, 06 Oct 2014 21:40:25 +0100 atomicbisf Posted By: jamesingramSteamy did you see my whispered comment on last page re costing of benQ. If you can find someone to sign it off then diy is possible. Vat is an issue though. You'd need a supply and commission deal. Probably unlikely to find a willing helpful pv company?

Hi James,

please could you whisper this to me too as I'd be interested as I need to know how much we'll need for reroofing + solar PV.

Thanks,
Ed]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210615#Comment_210615 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210615#Comment_210615 Tue, 07 Oct 2014 01:35:32 +0100 wookey Who would buy such a system?

People who understand that they have a carbon budget of 1, maybe 2, tonnes a year for _everything_ (travel, heating, stuff, food).

ST gives you a few MWh of (almost) carbon-free heat. 'payback' doesn't really come into it. Using PV instead can make sense, but mostly due to the external financial incentives. On an areal basis ST gets a lot more watts/m2 but does helpfully supply not enough for 1/3rd of the year and way too much for some of the summer. (PV also has this problem, but is not quite so unhelpfully skewed).

Mine cost £800 to install, which does make the finances look a lot better, and it's been great for 5 years now.]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210616#Comment_210616 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210616#Comment_210616 Tue, 07 Oct 2014 05:57:50 +0100 SteamyTea What sort of system do you have, FP, EV, homemade?
How is it plumbed in and did that 800 include a new cylinder?]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210625#Comment_210625 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210625#Comment_210625 Tue, 07 Oct 2014 09:11:50 +0100 djh What sort of system do you have, FP, EV, homemade?
How is it plumbed in and did that 800 include a new cylinder?"

The answers are at

http://wookware.org/solar/

http://wookware.org/pics/solar/]]> Solar Panels (for heating water) - why do it? http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210662#Comment_210662 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=12608&Focus=210662#Comment_210662 Tue, 07 Oct 2014 14:04:48 +0100 SteamyTea