How to protect consumers when you know soething isn't right - Thermodynamics

[Worcester]

The bandwagon's rolling ..

I guess you've all had the recent emails.

MCS (under pressure) have created a new standard for solar assisted heat pumps, aka thermodynamics.

This is now causing all sorts of action in the market places.

ALL of the previous sales led, commission based Solar PV organisations are now starting to leverage the value of MCS certification for these products and the importer / wholesaler is pushing it like it's the best thing since sliced bread.

We all now the results of the independent tests carried out show very little if any benefit of this technology in the UK climate - Gavin I know you were looking at this do your findings actaully show a financial payback for the technology?

My concern is that this will create another fiasco of ripped off pensioners and systems than don't deliver any value.

The gullible public will be swayed by a smooth salesman spouting MCS this and that, they may even give them an MCS certificate (sometimes) though as there are no financial incentives (FiT / RHI) there is no reason for them to comply with any of those design or installation standards whatsoever.

Time for a watchdog warning?

Have I got it all wrong? - Your thoughts ...

 

[TedM]

What makes you think that these won't be added to the RHI in the near future?

 

[Worcester]

What makes you think that these won't be added to the RHI in the near future?

Because from the test carried out so far, the UK installed CoP's are so low they don't meet the 2.5 requirement to be deemed renewable.

Also they'll need to go through the MCS ErP process for production of a SCoP which will be so low, the installers won't bother to register them on the MCS database.

Bearing also in mind that the big pusher of these systems has already lost one ASA ruling
https://www.asa.org.uk/Rulings/Adju...amic-Box-Ltd/SHP_ADJ_231310.aspx#.VmgM0L8jXm4

 

[The Solar King]

Like this ---

"Hi,

With the imminent demise of PV as a business model the time is right to
introduce your customers to the EliteTDCH the only indoor air source heat pump that produces hot water and
reduces central heating costs

Central Heating UK | Thermodynamic Central Heating | CO2 Exchange Ltd

Stupid name for a daft technology. We could keep a running score on the number of emails.

 

[TedM]

I thought they were claiming CoPs in the 3-4 range? Some models on that website are claiming 500W input and 2kW output.

Their pricing structure is interesting too, basically BOGOF. Plenty of alarm bells should be ringing.

 

[Worcester]

Like this ---

"Hi,

With the imminent demise of PV as a business model the time is right to
introduce your customers to the EliteTDCH the only indoor air source heat pump that produces hot water and
reduces central heating costs

And wild claims too:

The TDCH takes the waste heat from the room it is situated in with no discernible temperature drop

The ONLY way it can get that 'waste heat' is the boiler working harder!

Note those technologies DO NOT meet MCS requirements for a heat pump:

4.2.7 Hot water heat pumps delivering domestic hot water shall use waste heat from boiler rooms, waste heat from server rooms, or waste heat from external ambient air only as detailed in Commission Regulation (EU) No 814/2013 or anywhere that it can be shown that the extraction of heat by the heat pump is not depleting the building space heating.

 

[Gavin A]

there is waste heat available in the form of latent heat from the moisture content of the air, so it is technically possible to extract that latent heat and return drier air at the same temperature. Not sure if that's what they're actually doing, but it is technically possible to do it.

re thermodynamic panels....

Unfortunately the swimming pool site I had on test got ballsed up by the customer installing a massive heat exchanger because he thought the one we installed was too small, this then resulted in a pressure drop that was too great for the pump to be able to pump the fluid round at the required flow rate. This means that the unit is operating at a higher temperature than it should be, and is cycling regularly so it's cutting out about 15% of the time.

This is an installation issue rather than the fault of the unit supplied, although it does show up the problem of it not being inverter driven, but a basic on / off compressor.

Even with this though the COP is better than achieved by NAREC, albeit nothing spectacular.

I hope to get the heat exchanger swapped back out, at which point I expect the COP to improve significantly.

 

[Marvo]

there is waste heat available in the form of latent heat from the moisture content of the air, so it is technically possible to extract that latent heat and return drier air at the same temperature. Not sure if that's what they're actually doing, but it is technically possible to do it............

The phrase 'thin ice' springs to mind here. Depends how the moisture content in the air came to being there, if it was due to local evaporation as a result of energy being expended to drive HVACR for example then your looking at the changing enthalpy of an open system rather than waste heat or available latent heat surely...? Removing that latent heat by condensing that moisture will just cause more heat in the future to be lost back into latent heat by encouraging further evaporation from other sources into a relatively less humid environment.

In laymens terms you're robbing Peter to pay Paul because any latent heat you realise from the system will cause more energy to be consumed by the heating system. There's also comfort factor for occupants whereby relative humidity needs to remain within an acceptable band.

 

[Gavin A]

The phrase 'thin ice' springs to mind here. Depends how the moisture content in the air came to being there, if it was due to local evaporation as a result of energy being expended to drive HVACR for example then your looking at the changing enthalpy of an open system rather than waste heat or available latent heat surely...? Removing that latent heat by condensing that moisture will just cause more heat in the future to be lost back into latent heat by encouraging further evaporation from other sources into a relatively less humid environment.

In laymens terms you're robbing Peter to pay Paul because any latent heat you realise from the system will cause more energy to be consumed by the heating system. There's also comfort factor for occupants whereby relative humidity needs to remain within an acceptable band.

but in domestic situations houses are required to be ventilated to set levels in order to remove excess water vapour from the air, which comes almost entirely from showers, cooking, clothes drying, breathing, sweating rather than evaporation from standing water

We really do chuck away a fair amount of energy from our houses in this way, and it's mostly not recaptured even in MHRV (though some is).

This is probably a bit different in the UK to South Africa as I think our average atmospheric RH levels are significantly higher.

Also if it's capturing that energy from the outgoing air that would have been extracted anyway then it's just capturing energy that would have been lost via an extractor fan, or even to a lesser degree MHRV.

 

[Marvo]

Ahh, maybe I got the wrong impression, it sounded like it might be a commercial system, the regs Worcester quoted mentioned boiler rooms and server rooms etc. If it's small domestic then yes I'd agree you could recover latent heat from the bathroom or laundry if there's a tumble dryer with an MHRV but I doubt it would be worth jumping through the necessary hoops to recover latent heat specifically after that.

 

[Gavin A]

the necessary hoops is just adding a small heat pump condensor into the air extraction ducts, and compressor unit.

It's essentially where most of the energy for exhaust air heat pumps comes from, and is also why people get it so badly wrong when they need to extract more energy than is actually available in the outgoing air.

That's also potentially the issue with these exhaust air water heating units, as if they need more energy to heat the water than would be available from the air that would normally need to be extracted, then they'll just up the extraction rate, at which point they are just recycling heat from the central heating system.

So used correctly in the right situations they could be a sensible option,but mostly that's not going to be the case if they're just being pushed by sales led companies.

 

[Worcester]

Brings us back full circle..

Do we want to protect Mr & Mrs Nest Egg Retiree from having their savings plundered, or do we just let the sales led organisations have a rebirth and second opportunity to destroy public confidence in renewables?

 

[Gavin A]

well, theoretically MCS should be able to issue and enforce guidance / regulations that ensure these technologies are only sold for use in appropriate situations.

but I doubt those setting the standards have the technical understanding of the technologies to do that appropriately, nor the desire to do it being as most of those involved are from the companies who're 'manufacturing' these units (more like subbing the work out to actual manufacturing companies and putting their badge on it).

Maybe I'm wrong, but the MCS model doesn't really invoke confidence - entirely voluntary self selecting technical steering groups with no budget to bring in outside experts to advise.