Green Building Forum - PVT and Heat Pump Tue, 19 Dec 2023 08:20:16 +0000 http://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288678#Comment_288678 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288678#Comment_288678 Mon, 05 Apr 2021 19:50:44 +0100 renewablejohn PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288684#Comment_288684 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288684#Comment_288684 Tue, 06 Apr 2021 08:53:09 +0100 fostertom PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288685#Comment_288685 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288685#Comment_288685 Tue, 06 Apr 2021 09:45:52 +0100 renewablejohn
link below

https://agibaheating.com/2power-system/]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288687#Comment_288687 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288687#Comment_288687 Tue, 06 Apr 2021 10:12:51 +0100 renewablejohn
https://triplesolar.eu/en/introduction/]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288689#Comment_288689 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288689#Comment_288689 Tue, 06 Apr 2021 10:45:02 +0100 fostertom
The Agiba site is hard to see that it's anything special. But looks like you're following developments and can interpret - so wd you like to outline how you'd see it configured as (part of?) a system and what kind of performance you'd hope for?

As it stands, I'm advising clients that heat pumps aren't actually a substitute for a boiler unless the heat emitters can work at tepid temperature, which usually means a pretty well insulated house so heat demand is low relative to emitter surface area; then either UFH or the existing rads which after house insulation are well 'oversized'. If required to deliver water at 'normal' (60C-plus) rad temp, heat pumps' CoP suffers badly. So are we saying that PVT, or Agiba in particulasr, can overcome that CoP problem in a hard-to-insulate house?]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288690#Comment_288690 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288690#Comment_288690 Tue, 06 Apr 2021 10:45:59 +0100 owlman The downside, as with all Solar PV and ST in the UK, especially in the North, is its inability to produce enough, of whatever it does, during the depths of the winter heating season, unless of course you've got loads of it.
IMO, by all means max out the straightforward solar PV, but then keep it simple and use its output to supplement the running of an ASHP, and/or immersion heater. What is the point of a sea of DHW in the middle of Summer.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288691#Comment_288691 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288691#Comment_288691 Tue, 06 Apr 2021 11:01:29 +0100 WillInAberdeen
Just about any house will benefit from a heatpump now, in carbon terms. Even if it has to run radiators at >60deg for a few days in midwinter with resistance top-up, there will be compensating benefits during all of the other milder months of the heating season, when the radiators can happily run cooler. This is expressed as the Seasonal Performance Factor SPF, which is derived from the CoP but corrected for the fact that only a very few days of the total heating season are -5degC.

This has the double benefit that the heatpump CoP is better in milder air temperatures (expressed as the SCoP which you can look up) and the house CH can run cooler in milder months. These are combined to calculate the average SPF over the whole heating season.

So long as the SPF is >1 (which it invariably is, usually >3) the heatpump is greener than electric-resistance, which itself is now greener than gas.

Whether it is cheaper, is a different matter....]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288692#Comment_288692 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288692#Comment_288692 Tue, 06 Apr 2021 11:10:01 +0100 WillInAberdeen PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288695#Comment_288695 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288695#Comment_288695 Tue, 06 Apr 2021 11:29:21 +0100 owlman PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288698#Comment_288698 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288698#Comment_288698 Tue, 06 Apr 2021 12:02:36 +0100 Shevek
No ducts. No ventilators that help evaporation process. No defrost cycles. Primary circuit does not need to dissipate excess heat on hotter days. You can also feed the cylinder with backup mains electric, PV, boilers, heat pumps, heat exchangers, solar collectors.

https://www.energie.pt/en/solar-thermodynamic

Edit: made in Portugal but also operate in the UK:
https://www.energie.co.uk/products/index.html]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288705#Comment_288705 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288705#Comment_288705 Tue, 06 Apr 2021 12:37:39 +0100 djh PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288707#Comment_288707 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288707#Comment_288707 Tue, 06 Apr 2021 13:08:02 +0100 renewablejohn Posted By: ShevekCame across this pretty neat system the other day, which combines solar hot water + heat pump technology. I prefer this idea to PV + heat pump.

No ducts. No ventilators that help evaporation process. No defrost cycles. Primary circuit does not need to dissipate excess heat on hotter days. You can also feed the cylinder with backup mains electric, PV, boilers, heat pumps, heat exchangers, solar collectors.

https://www.energie.pt/en/solar-thermodynamic" rel="nofollow" >https://www.energie.pt/en/solar-thermodynamic

Edit: made in Portugal but also operate in the UK:
https://www.energie.co.uk/products/index.html" rel="nofollow" >https://www.energie.co.uk/products/index.html

This is similar to my thinking of the solar thermal being linked direct to a water/water heat pump just going one stage further and replacing the solar thermal panel with the agiba type 2 power panels (PVT) It would still allow a top up of heat in the depths of winter from my existing biomass boiler but for the majority of the year would provide all heating, hot water and electric.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288708#Comment_288708 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288708#Comment_288708 Tue, 06 Apr 2021 13:16:38 +0100 renewablejohn Posted By: djhThe key point of the Agiba system as I understand it is not so much the PVT panels as the seasonal heat store - warm earth under the foundations powered by and extracted from using a heat pump. Similar to ICAX that we've discussed on here before.

Was not looking at that aspect or going down that route. Just looking at PVT panels providing a heat source for a water to water heat pump. I have a welsh slate roof and the slightest rays of sunshine it gets very warm.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288713#Comment_288713 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288713#Comment_288713 Tue, 06 Apr 2021 15:34:36 +0100 fostertom Posted By: owlmanTom, out of curiosity, why the emphasis on A2W systems in your client discussions. Is it the potential for RHI, or something else?Not RHI, just what's an alternative to the existing fairly recent gas combi, in a hard to insulate house (Listed Victorian 3-storey terrace town house)? We are doing roof and limited wall insulation which I guess will reduce heating demand by 40%.

Another avenue was latest-tech electric storage heaters plus smart meter and half-hour variable demand-pricing tariff, with clever software to cherry-pick best tariffs at any time of day or night. But the whole point of smart metering is to eventually even out demand swings on the grid, so hi-lo tariff differences to cherry-pick will even out too.

I also asked the forum if there's any kind of consultant who could advise on such cutting-edge strategies - I feel out of my depth to advise.

Posted By: WillInAberdeenTom, the other trick is that many older houses have the old style radiators, single panel, or double without fins. If you swap out the old style radiators for modern radiators the same dimensions, double with fins, you get twice or more the heat emitting area without paying to alter the plumbing, so can run the CH cooler
The house has recent cast iron 'hospital' rads - I guess they're quite high on output per frontal area already?]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288715#Comment_288715 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288715#Comment_288715 Tue, 06 Apr 2021 16:32:03 +0100 owlman It doesn't come with all the extras baggage of A2W and if RHI isn't part of the equation why complicate things.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288727#Comment_288727 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288727#Comment_288727 Tue, 06 Apr 2021 17:46:42 +0100 djh Posted By: fostertomBut the whole point of smart metering is to eventually even out demand swings on the grid, so hi-lo tariff differences to cherry-pick will even out too.
Well no, because it is the different pricing that gives motivation to provide the balancing, so yes there may be some reduction but it certainly won't even out.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288729#Comment_288729 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288729#Comment_288729 Tue, 06 Apr 2021 18:06:01 +0100 WillInAberdeen
You'd have to check the data of their particular radiator, but this one:

https://www.screwfix.com/p/arroll-4-column-cast-iron-radiator-660-x-874mm-black-3726btu/8415f

Has only 65% as much output as this double fins one, similar dimensions

https://www.screwfix.com/p/stelrad-accord-compact-type-22-double-panel-double-convector-radiator-700-x-900mm-white-5797btu/170hx

Not sure what your client would feel about that... but it would work with cooler CH !]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288733#Comment_288733 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288733#Comment_288733 Tue, 06 Apr 2021 22:01:45 +0100 fostertom owlman, will think about warm-air heating but doubt it somehow.
I see hi-tech storage rads are bl**dy expensive - not 'the cheap option' as was.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288742#Comment_288742 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288742#Comment_288742 Wed, 07 Apr 2021 12:22:39 +0100 djh Posted By: fostertomI see hi-tech storage rads are bl**dy expensive - not 'the cheap option' as was.
I don't understand them or their pricing. I think it's just 'fashion' pricing. I can't see how old-fashioned storage heaters and a 'smart' control system wouldn't do the same thing.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288744#Comment_288744 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288744#Comment_288744 Wed, 07 Apr 2021 13:14:03 +0100 Nick Parsons
I won't be in a rush to buy any.]]> PVT and Heat Pump http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288746#Comment_288746 http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17006&Focus=288746#Comment_288746 Wed, 07 Apr 2021 16:40:22 +0100 fostertom Posted By: djhI can't see how old-fashioned storage heaters and a 'smart' control system wouldn't do the same thingAnd a lot easier to hack with the kind of AI I had in mind, 2 posts earlier. But prob the heat-storage density, retention/insulation and regulable output will be significantly improved over the 'old-fashioned'. Or not - what do we think?]]>