Bubble Bursts on those installing Solar Thermodynamics

[solarsavings]

If you have bought these systems and are testing the results before selling them to the public then fair play to you.

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I did that with solar thermal and PV. Did you or the solar king?

By your own admission time will only tell what the performance of thermodynamics will be in the winter time. You also agree that couldn't get the information you needed to see if the claims stack up.

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In the early days you couldn't get information on how solar thermal or pv would work either it didn't stop us driving the industry forward. From experience I can now tell my customers that both are next to useless in the winter because they are next to useless and don't work at night. The thermodynamic system certainly seems to.

If however you have done what many others have done and sold these systems with promises of savings and RHI payments then that is that you need to defend

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If, and when I'm happy that the system does work and the economics make sense then I won't have any problem selling it providing I'm convinced.
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[Gavin A]

Not sure what you mean by this post. If you have been fitting thermo-dynamics then defend your position. If you cant defend it don't come on here and try and cover up your own bad practices by name calling. As i said in the OP We wouldn't fit this technology because we weren't convinced by the figures. I have seen nothing since that has made me change my mind.

These are not solar thermal systems and if you have been selling them as such then you could have a serious problem. We could have fitted these systems if we wanted but chose not to. Why would we be envious of others who take on work we would rather not get involved in? If there's any arrogance being shown its coming from companies that fit this type of technology in order to make a profit with out any thought about the value they are giving to their customers.

Solarsavings - If I have misunderstood the sentiment of your post please let me know and I will withdraw these comments.

I think you're out of order here tbh.

It wouldn't have taken much effort to have searched the forum to find out that solarsavings is actually doing all of us and the industry in general a favour by trialling these products in a monitored test situation to find out how the claims stack up against reality.

There's zero reason to think that these products won't actually work, and work well in the correct set up. The problem is that they're potentially misclassified for MCS purposes, and because of the attempt to keep this classification they've not published the COP figures as they would have to if they were listed as heat pumps.

I don't actually see why anyone would particularly need a heat pump accreditation to fit them, as they're very basic plug and play bits of kit*, probably simpler to install than a standard solar water heating system in a lot of respects, and there's certainly no need for any of the complex heating load sizing issues that come into play with heat pumps. They also certainly do take a significant amount of their energy from the sun directly, so are really more of a hybrid between a heat pump and solar panel, hence the classification issues - they just have the advantage of being able to also draw energy from the surrounding air when the sun isn't shining at lower COP's (but still probably better than an ashp as they don't have to power a big fan unit).

I'm not saying they haven't been mis-sold, as they clearly have been by some companies, but then so have PV and solar water heating systems, the problem is with the companies mis selling the products not the products themselves.



* though an fgas certificate would be needed - something that I don't believe is needed for MCs heat pump certification either, so is a separate issue.

 

[The Solar King]

No envy and arrogance, just a passion for an industry I believe in. I have no wish to see Solar Thermal dragged in to the mud in the way PV has been by businesses more interested in a quick buck than serving the needs of customers. Please note, I am not saying this as any reflection on Solar Savings. You would not have gone to the extent you have in evaluating this equipment if you were in that camp. It is also highly unlikely you would contribute to this forum either. However there are others out there without your scruples.

Sadly data for cambridge is still unlikely to substantiate whether this technology will work in off grid areas in parts of northern Scotland. My issue with this kit is the claims made for it relating to space heating. A cost effective space heating solution is still the holy grail of renewables. I would not have bothered challenging the veracity of the claims being made had this not been the case. This is not the first time claims have been made for systems using solar thermal for space heating. When you drill down, there is never any data available for locations north of the Wash.

As a supplier, why should you have to find out whether it works or not? Would you buy a car and crash it to see if you died or survived?

I know exactly what the performance of ST and PV is where I operate. I advise prospective customers as to likely performance and let them make their own reasoned decision as to whether the proposed technology is right for them. I cannot do this with this technology. If you go back and look at the original thread started on this topic, you will see I am not alone in my concerns.

I can understand your frustration, I would love it to do what it says on the tin. Taking time to write to Ofgem is not something I do lightly. Unfortunately if someone ends up defecating on their own doorstep with this stuff, they defecate on everyone else's as well.

 

[The Launderer]

I think you're out of order here tbh.

It wouldn't have taken much effort to have searched the forum to find out that solarsavings is actually doing all of us and the industry in general a favour by trialling these products in a monitored test situation to find out how the claims stack up against reality.

There's zero reason to think that these products won't actually work, and work well in the correct set up. The problem is that they're potentially misclassified for MCS purposes, and because of the attempt to keep this classification they've not published the COP figures as they would have to if they were listed as heat pumps.

I don't actually see why anyone would particularly need a heat pump accreditation to fit them, as they're very basic plug and play bits of kit*, probably simpler to install than a standard solar water heating system in a lot of respects, and there's certainly no need for any of the complex heating load sizing issues that come into play with heat pumps. They also certainly do take a significant amount of their energy from the sun directly, so are really more of a hybrid between a heat pump and solar panel, hence the classification issues - they just have the advantage of being able to also draw energy from the surrounding air when the sun isn't shining at lower COP's (but still probably better than an ashp as they don't have to power a big fan unit).

I'm not saying they haven't been mis-sold, as they clearly have been by some companies, but then so have PV and solar water heating systems, the problem is with the companies mis selling the products not the products themselves.



* though an fgas certificate would be needed - something that I don't believe is needed for MCs heat pump certification either, so is a separate issue.

I am not out of order for defending myself from accusations of envy or arrogance.

Of course it is to be applauded that Solarsavings is carrying out research and by his responses it is now obvious to me that he isn't one of the installers that I have a problem with. But why should he have to do research on systems being sold to the public in large quantities - The research should have been carried out by the manufacturers and wholesalers and independently verified.

I am not sure what is happening elsewhere in the country but up here in Scotland there are full page adverts in the papers, call centres, snake oil salesman all pushing this technology. It is being sold as a solar thermal product.

They are also being sold as complete heating systems so in my opinion it is essential that someone carrys out "complex heat loading that come into play with heat pumps" THEY ARE HEAT PUMPS. The reason Air Source Heat pumps have such a big fan is so that they can push large volumes of air and extract the small amount of heat that is available. I have no doubt that on a sunny day the solar gain produced by the panels will produce a high COP rating. My concern is on dull days, cold days, night time (from 4.00pm in Scotland) the tiny amount of heat energy being captured by these panels will see a COP rating well below 1.0. So in the heating season customers using these systems will find their bills doubling or trebling from when they used to use gas or oil.

Am I wrong? Maybe? I would like someone to prove it!!

 

[Gavin A]

I am not out of order for defending myself from accusations of envy or arrogance.

well you certainly came in swinging on this thread, and seemed intent on tarring everyone with the same brush, but let's move on eh.

I am not sure what is happening elsewhere in the country but up here in Scotland there are full page adverts in the papers, call centres, snake oil salesman all pushing this technology. It is being sold as a solar thermal product.

They are also being sold as complete heating systems so in my opinion it is essential that someone carrys out "complex heat loading that come into play with heat pumps" THEY ARE HEAT PUMPS. The reason Air Source Heat pumps have such a big fan is so that they can push large volumes of air and extract the small amount of heat that is available.

as I said, this is more of a problem with the companies selling the stuff than the actual technology itself.

If they're being sold as full house heating systems, then that's obviously a different matter, but I've only seen them sold as water heating systems - though I know they do offer full heating options.

For the full heating systems obviously proper heatload calcs would be needed, and tbh I'm extremely dubious that the systems should be fitted for this purpose in anything other than passive houses or houses that are otherwise extremely well insulated. Though maybe if the alternative was straight resistive heating then it could be justified.

I have no doubt that on a sunny day the solar gain produced by the panels will produce a high COP rating. My concern is on dull days, cold days, night time (from 4.00pm in Scotland) the tiny amount of heat energy being captured by these panels will see a COP rating well below 1.0. So in the heating season customers using these systems will find their bills doubling or trebling from when they used to use gas or oil.

Am I wrong? Maybe? I would like someone to prove it!!

well it'd be easy enough to disprove your statement about the COP falling below 1 theoretically.

The product uses the same technology essentially as any other air source heat pump, and as I said before, doesn't have a fan unit to power. There is no logical reason at all that in a properly set up system the COP of these units won't be at least the same or better than an ASHP operating at the same air temperatures if correctly sized. IF they're cooling the surrounding air faster than the air can be replaced then this will impact on the air temperature and COP, but even in no wind situations natural convection laws should apply, so air will sink as it's cooled drawing in new air over the panels. Even at -10 or lower the COP should be above 1 though, as is the COP on ASHP even when they're using resistive loads to boost the heat, and defrost the unit. I agree it probably won't be much above 1, but I don't see why it would fall to below 1.

My concern with it as a heating unit is that I'm sure I read somewhere that it actually cuts out at -10, so would need an immersion back up or alternative heating source capable of supplying the full heat demand for the property below -10 deg if used as a heating source as opposed to just water heating.


To conclude - I tend to agree with you re using these systems for full house heating, particularly in the wilds of scotland. I'm far less concerned about them if used for water heating only, and think that for this purpose only they're a reasonably fit for solar water heating MCS requirements.

 

[solarsavings]

Gavin as ever a sensible analysis and your post has highlighted something I couldn't understand about the defrost cycle, but it's starting to make sense now ;-)

I found this in my inbox this afternoon.

[h=4]Dear Tony,


You may have received the attached letter from MCS regarding thermodynamic solar systems which tells you to contact your CB.

We are not in a position to give any guidance on whether you should continue installing these systems with the intention of receiving RHI payments. As for refrigerant issues raised in the letter we do not certificate safe use of refrigerants and you would need to ensure you meet all the necessary requirements of qualification and/or registration for this type of work.

We would suggest that you cease installation for clients who are hoping to receive RHI. It is likely if the product is accepted under MCS and RHI that they will deem it to be heat pump not solar thermal.

Provided that the issues regarding refrigeration competences are addressed by your business and because the product is approved by the MCS equivalence rule by Keymark, Benchmark will certificate these installations, however we cannot be held responsible or liable for any subsequent decisions and ruling made by DECC or the MCS regarding the status of this type of system in relation to the MCS and RHI and for any loses or claims arising from the installation of them.

As a Certification Body we are extremely perturbed that the MCS felt it was appropriate to direct installers to their CB for guidance on what is a DECC and MCS matter over which we have no control or influence.

Therefore, we recommend that you in fact contact the MCS for clarification.[/h]

 

[Berneray]

I'm finding this thread fascinating as I have come up against salesmen from two of the large national pv companies that are now moving body and soul into ThermoDynamics. Both instances were in the last two days.

First one was an end terraced house on mains gas with combi boiler. Two pensioners using no more than £60 per month for gas. This also covered their cooking. Washing machine cold fed....so the amount they were spending on hot tap water can't have been more than £20. Salesman recommended a 250 ltr system for £8500 and said they could earn as much as £1200 a year from RHI.

Second was a large three storey house with 15 year old boiler and hot water tank. Also on mains gas and spending £110 per month on gas. Different salesman. Different company. Recommended a 250 ltr system again this time for £11500. But could do a deal for £9500. Again pushed the RHI.

What was interesting for me is that these were both Internet leads for PV Solar NOT Solar Thermal yet in both cases the sales reps went gung ho for thermodynamic panels. Guess where the big commission cheques are.

Like a lot of the guys here we are staying clear and just watching from the side lines for now.......

And as an aside.....surely a 4kwp system backed up with an Immersun Unit is a much better and more secure bet than any ThermoDynamic panel regardless of whatever RHI is agreed

 

[rhinoman]

I'm new here and install a little PV but its not my main line of business and only added it as an additional service for my existing client base so don't consider myself an expert.

I was interested in finding out more about thermo dynamics so I got a salesmen round about this but he clearly didn't have much idea about what was required, we have underfloor heating downstairs and was considering this as a whole house solution to "get rid of our gas bill".

He quoted a 250l tank and compressor for the water heating at about £7200 and then quoted about the same or another tank and panel for the heating. He recommended we keep the gas boiler to top up the generated water from 55C to 65C for the rads upstairs. He did say we could swop them for aluminium rads though that run as efficiently at the cooler temperature though. He also said it would qualify for the RFI next year even if fitted now.

Two tanks doesn't sound right to me, how is it suppose to work? Can the "heatpump/compressor unit" be combined with a standard unvented cylinder?

Incidently I found a course that was about £900, took about a week and would be enough to get the fgas certification.

 

[wazzer]

I'm new here and install a little PV but its not my main line of business and only added it as an additional service for my existing client base so don't consider myself an expert.

I was interested in finding out more about thermo dynamics so I got a salesmen round about this but he clearly didn't have much idea about what was required, we have underfloor heating downstairs and was considering this as a whole house solution to "get rid of our gas bill".

He quoted a 250l tank and compressor for the water heating at about £7200 and then quoted about the same or another tank and panel for the heating. He recommended we keep the gas boiler to top up the generated water from 55C to 65C for the rads upstairs. He did say we could swop them for aluminium rads though that run as efficiently at the cooler temperature though. He also said it would qualify for the RFI next year even if fitted now.

Two tanks doesn't sound right to me, how is it suppose to work? Can the "heatpump/compressor unit" be combined with a standard unvented cylinder?

Incidently I found a course that was about £900, took about a week and would be enough to get the fgas certification.

Then you have to do unvented water (part G) and your WRAS

 

[The Launderer]

well you certainly came in swinging on this thread, and seemed intent on tarring everyone with the same brush, but let's move on eh.

I started the thread by posting a letter I received from MCS as a Solar Thermal Installer. I have suspected for some time that people installing this technology were taking a risk. This technology has been wrongly accredited as a solar thermal system and it was never any such thing. The heat pump element of the systems have not been MCS approved therefore if MCS decide that this technology is a heat pump it will carry no approval. To compound matters there is no data available that proves the technology works. So we have a technology with no approval and no test figures hence my post "The Bubble Bursts"

well it'd be easy enough to disprove your statement about the COP falling below 1 theoretically.

The product uses the same technology essentially as any other air source heat pump, and as I said before, doesn't have a fan unit to power. There is no logical reason at all that in a properly set up system the COP of these units won't be at least the same or better than an ASHP operating at the same air temperatures if correctly sized. IF they're cooling the surrounding air faster than the air can be replaced then this will impact on the air temperature and COP, but even in no wind situations natural convection laws should apply, so air will sink as it's cooled drawing in new air over the panels. Even at -10 or lower the COP should be above 1 though, as is the COP on ASHP even when they're using resistive loads to boost the heat, and defrost the unit. I agree it probably won't be much above 1, but I don't see why it would fall to below 1.

There is a fundamental difference between this technology and other Air Source Heat Pumps. With standard ASHP you have a very big fan pulling in large quantities of air and extracting the available heat. With thermodynamics you have a pump pushing a liquid around a circuit. I have seen these panels and the water ways on the panels don't look bigger than 8-10mm (maybe its more?) Anyway, the flow of heat in this type of circuit is nowhere near the amount that can be achieved by a fan unit. In bright sunlight the panel will have sufficient solar gain to give reasonable COP rate but in the dark or at low temperatures the heat gain won't be sufficient to overcome the poor flow rate of the heat transfer medium.

Why would I want to consider this system at all? You fill your roof with horrible black panels and there is no proof that they work. For much less money I could buy an Ecocent unit which is an MCS registered heat pump DHW cylinder combination where there are facts and figures and COP ratings that I can use for comparison purposes.

The whole thing is ridiculous. Nobody should be installing this until there are test results that proves it works.

Oh and I just noticed on another thread that a COP rating of less than 1.0 has been found.

 

[Gavin A]

Both ASHP and Thermodynamic systems use a pump to push fluid around a system to transport low grade heat from an air to liquid heat exchanger to a compressor unit.

The difference is that in an ASHP unit there is a relatively small heat exchanger surface area with a fan forcing a rapid flow of air across it, whereas with the Thermodynamic system there is a large surface area to compensate for the low rate of air flow across the unit.

You're right that there won't be an equivalent flow of heat from these units compared to a big ASHP, but then they don't claim that there will be unless you're using multiple units. The comparison with the ecocent is probably about right.

 

[Gavin A]

Oh and I just noticed on another thread that a COP rating of less than 1.0 has been found.

You didn't notice that the calculations they used to get to that figure were a load of rubbish though?

Or that I'd given a link to a test report from the lab they're mentioned that gave COP figures of 2.7-3.3 depending on the method used?

 

[The Launderer]

You didn't notice that the calculations they used to get to that figure were a load of rubbish though?

Or that I'd given a link to a test report from the lab they're mentioned that gave COP figures of 2.7-3.3 depending on the method used?

Gavin - You obviously know your stuff but you repeatedly ignore the several rather large elephants in the room ie.:

1. There is no UK test data proving it works at all
2. It is likely to be re-designated as a heat pump and the heat pump element of the system is not MCS approved
3. With no MCS accreditation there will be no RHI
4. Customers who have bought this will be expecting RHI are almost certainly going to be disapointed and
5. The costs of installing this without RHI means no payback so the whole thing is pointless.

I would be grateful if you could address these fundamental issues rather than picking out elements of my posts that you are able to find some issue with.

 

[Gavin A]

Gavin - You obviously know your stuff but you repeatedly ignore the several rather large elephants in the room ie.:

1. There is no UK test data proving it works at all
2. It is likely to be re-designated as a heat pump and the heat pump element of the system is not MCS approved
3. With no MCS accreditation there will be no RHI
4. Customers who have bought this will be expecting RHI are almost certainly going to be disapointed and
5. The costs of installing this without RHI means no payback so the whole thing is pointless.

I would be grateful if you could address these fundamental issues rather than picking out elements of my posts that you are able to find some issue with.

I'm not ignoring them, I agree with all of that, I just disagree with people making out that a technology doesn't work just because they don't understand it, and the owners haven't jumped through to correct MCS hoops.

What I'm saying is that we shouldn't thrown the baby out with the bath water here - there's no evidence that the technology doesn't work if used properly, and no technical reason why it shouldn't.

I've recently seen trade prices that I think should make this stuff price competitive with standard solar thermal systems for water heating, and the systems should be a good alternative option particularly where space is limited, or a solution that supplies year round hot water is desirable.

 

[Gavin A]

What would be far more useful IMO is if the regulatory bodies would actually crack down on the sorts of sales malpractices that are really starting to blight this industry.