LVP Thermodynamic solar Panels

Do-more

@braka Just wondering if you can update us on your energy usage for the thermodynamic panels and that they are still working well for you?

Also could you please indicate your general location so that I can relate your energy usage to local weather data.

Thanks.

just do it

Do-more wrote: »

@braka Just wondering if you can update us on your energy usage for the thermodynamic panels and that they are still working well for you?

Also could you please indicate your general location so that I can relate your energy usage to local weather data.

Thanks.

Hey Do-more. I was looking through some threads on various heat pumps last night. What did you go for in the end? What did you conclude about the exhaust air HP?

braka

Do-more wrote: »

@braka Just wondering if you can update us on your energy usage for the thermodynamic panels and that they are still working well for you?

Also could you please indicate your general location so that I can relate your energy usage to local weather data.

Thanks.

Hi Do-More, I was going to put up data when March was over but since I have got a few more requests for data I'm giving it right up to today 23rd March.

Currently costing less than €5/week (25Kw / week) so very happy ....and the weather has been poor enough so I expect April will cost less.

Hope you find the data useful.

Regards.

Do-more

Thanks very much for that braka, I had actually mis-read the date of your last update and thought it was from a year ago! So good of you to update again so soon.

I think it is really valuable information for anyone considering this type of system to have good data on them. I think the manufacturers and distributors have been rather lacking in giving performance data from real world installations or proper test data against European standards.

The more owners who can come on board with their own performance data the better.

If you could post the location of your nearest met station I would appreciate it.

@ Just do it, I don't want to bring this thread off topic, I will PM you later with an update.

braka

Do-more wrote: »

Thanks very much for that braka, I had actually mis-read the date of your last update and thought it was from a year ago! So good of you to update again so soon.

I think it is really valuable information for anyone considering this type of system to have good data on them. I think the manufacturers and distributors have been rather lacking in giving performance data from real world installations or proper test data against European standards.

The more owners who can come on board with their own performance data the better.

If you could post the location of your nearest met station I would appreciate it.

@ Just do it, I don't want to bring this thread off topic, I will PM you later with an update.

Knock airport and Belmullet would be the nearest met stations to me.

freddyuk

Can you tell us what the energy monitor reads (watts) when the unit is in recovery mode ie. it is reheating from cold after bath of water etc.? I think I asked this last year.
Many thanks

braka

freddyuk wrote: »

Can you tell us what the energy monitor reads (watts) when the unit is in recovery mode ie. it is reheating from cold after bath of water etc.? I think I asked this last year.
Many thanks

Hi freddyuk,
At the moment its running and the readings are:
V = 232
A = 2.5
P.F. = 0.69
Watts = 401

Hope this helps.

jockcass

JohnnieK wrote: »

I think you'll be waiting for that freddy :D

Any feedback on these or updated systems & costs ?

MOTM

braka wrote: »

I have to say that I am very happy with how economical the system has been to date (less than 5euro/week) and it has surpassed my expectations.

Please feel free to comment.

< €5/wk
So < €250/yr
Would this not be near comparable to the running cost of a condensing boiler system with decent controls (I'd expect would certainly be less than €300/yr). Add conventional solar water heating with a solar fraction of 50% and the water heating costs would be a good bit less than the LVP system.

Curious Geroge

Great post. Great information from braka.

Starting a new build so early stages of what's to be done. If I use this system, can I assume that the same hot water tank can be heated by my back boiler and condensing boiler ? I'd expect that during the irish summer, the back boiler and condensing boiler (oil or gas) would'nt need to be switched on.

Can someone tell me how installation costs relate between solar and thermodynamic ?

Braka, could you PM your make and model.

ccsolar

Curious Geroge wrote: »

Great post. Great information from braka.

Starting a new build so early stages of what's to be done. If I use this system, can I assume that the same hot water tank can be heated by my back boiler and condensing boiler ? I'd expect that during the irish summer, the back boiler and condensing boiler (oil or gas) would'nt need to be switched on.

Can someone tell me how installation costs relate between solar and thermodynamic ?

Hi George
Yes , You can connect your oil and solid fuel to this system.
You will need to inform your supplier of this as they will need to provide a tank with 2 extra coils, There is an additional charge of €100 per coil.
Make sure you get the stainless steel tank and not the Enamel tank.
The installation cost is normally around the €4500 for a standard 300 litre tank + 1 panel.

Cc

Tommyboy08

MOTM wrote: »

< €5/wk
So < €250/yr
Would this not be near comparable to the running cost of a condensing boiler system with decent controls (I'd expect would certainly be less than €300/yr). Add conventional solar water heating with a solar fraction of 50% and the water heating costs would be a good bit less than the LVP system.

Of course it would be cheaper to heat the water with oil and the installation cost of €4000 would have put a lot of oil in your tank,
All heat pumps suffer badly when heating water to 50C or anywhere near this temp and the cop would fall to about 2.5 or so and that's not even taking into account running this system on a cold day or worse a cold night, cop of well below 2. Condenser boiler would have a cop of about 2.2 , Just imagine running your air to water unit with the fans turned off and see how efficient things get,
Compressors should only last about 8 to 10 years running at those temps also,
Just can't see the payback at those figures!

shane0007

Tommyboy08 wrote: »

Condenser boiler would have a cop of about 2.2

Where did you get that infotmation???
The last 26kw condensing boiler I fitted did not give me 57.2kw!!!!
How can an oil or gas boiler give you more kw output than the input kw given from the fuel being used in it?

Condenser

shane0007 wrote: »

Where did you get that infotmation???
The last 26kw condensing boiler I fitted did not give me 57.2kw!!!!
How can an oil or gas boiler give you more kw output than the input kw given from the fuel being used in it?

In terms of the cost per kw he's fairly close, if you compare it in cost per kw to a heat pump with a COP of 2.
9.2kw @ 87c/l = 9.4c kw
2kw @ 18c/kw = 9c kw

Condenser

Biggest problem with these systems is you can only control the superheat across the evaporator in a very close range. If its too cold theres no superheat and liquid returns to your compressor causing damage. If its too warm you get too much superheat and the overheated gas cooks the compressor. Neither a good situation.
You cannot control this without a motive force speeding up or slowing down the energy collected. Its not like its a new technology. Was used in NZ years ago and was abandoned for the same reason, its also no different to the ice stick which has similar problems.

shane0007

Condenser wrote: »

In terms of the cost per kw he's fairly close, if you compare it in cost per kw to a heat pump with a COP of 2.
9.2kw @ 87c/l = 9.4c kw
2kw @ 18c/kw = 9c kw

Oil = €0.87/Litre = 10.8kw for 1 litre
=> 1kw = €0.08 but this is 100% efficiency with no system losses & hw being able to transfer the total load of a 26kw boiler at time of energy production. It can't so losses on dhw only circuit will be far greater.
Heatpump = €0.18 /kwh
=> @ COP 3, 1kw €0.18 / 3 = €0.06
Or @ COP 2, 1kw €0.18 / 2 = €0.09

I suppose my point is the figures work out similarly in an ideal world comparing 100% efficiency on both but in reality an oil or gas boiler cannot really deliver 100% system/circuit efficiency. The HE gas boiler will be far superior to the oil boiler due to its ability to modulate down once the return temp rises sufficiently.

Condenser

shane0007 wrote: »

Oil = €0.87/Litre = 10.8kw for 1 litre
=> 1kw = €0.08 but this is 100% efficiency with no system losses & hw being able to transfer the total load of a 26kw boiler at time of energy production. It can't so losses on dhw only circuit will be far greater.
Heatpump = €0.18 /kwh
=> @ COP 3, 1kw €0.18 / 3 = €0.06
Or @ COP 2, 1kw €0.18 / 2 = €0.09

I suppose my point is the figures work out similarly in an ideal world comparing 100% efficiency on both but in reality an oil or gas boiler cannot really deliver 100% system/circuit efficiency. The HE gas boiler will be far superior to the oil boiler due to its ability to modulate down once the return temp rises sufficiently.

I allowed for 92% efficiency but how and ever. My point was that hes not that far out on his figures an oil boiler does have roughly the equivalent cost per kw as a heat pump with COP of 2.

shane0007

Point taken.
That figure is only if the boiler can deliver down to what the cylinder coil can take, there are no system losses & therefore there is no wastage of the fuel due to being over-sized for the job.
I am an oil & gas man but I am becoming more open to heat pumps for dhw only. I am personally not a lover of them for heating whole houses.
I think they have their place in the market & I am very much open to be more educated about them.

deandean

My running costs for water heating using a modern, modulating gas condenser boiler, 180L copper cylinder, system set up for 'summer' :rolleyes: with all rads off, circulation pump set to low speed, cylinder 'stat set to highest:

based on gas meter readings, it costs me 55 cent in gas to heat the cylinder from cold to 65DegC, with the boiler turned on for 80 minutes.

This is enough hot water for the day. If hot water runs out..sorry kids, wait 'till tomorrow to wash your hair.

Total system cost: zero.

A thermodynamc system wouldn't be cost effective in my house which has an existing, modern GFCH system.

A thermodynamc system may be a solution in a very modern house that's almost passive and you have no c/h system & just need hot water; or if you are heating the house with a solid fuel stove and just need a hot water system.

Electricity is the purest form of energy, and is expensive. Of all the energy sources, electricity costs are going to increase the most due to the 'renewables levy' we will all be paying for the huge kW/h cost from wind farms...bring back nuclear...but that's over to the politics forum.

Condenser

shane0007 wrote: »

Point taken.
That figure is only if the boiler can deliver down to what the cylinder coil can take, there are no system losses & therefore there is no wastage of the fuel due to being over-sized for the job.
I am an oil & gas man but I am becoming more open to heat pumps for dhw only. I am personally not a lover of them for heating whole houses.
I think they have their place in the market & I am very much open to be more educated about them.

Shane, heat pumps are far more efficient at low temp so really space heating is where they shine. They struggle with DHW and their efficiency drops significantly. The only thing that counteracts that is the relatively short period of time they'll need to run at those temps and systems like fresh water systems keep the running costs low.
The problem remains in this country that very few people have a clue what they're really fitting and how it actually works and therefore don't know how to optimize their performance nor do most of them care.

shane0007

Condenser wrote: »

Shane, heat pumps are far more efficient at low temp so really space heating is where they shine.

This is not my forte but why is that most & I mean in the region of 8/10 people are not happy with them heating their space heating. I have never installed one for space heating but am very interested in them for dhw.
My own thoughts on why they can have poor performance & high bills is due to poorly insulated homes so high heat loss results in pump difficulty in keeping up with the demand required.
If this is true, then for dhw it should be much easier to achieve due to factory set conditions, such as factory insulation, factory settings, controls, etc.
Am I on the right track or miles away?

Condenser

shane0007 wrote: »

This is not my forte but why is that most & I mean in the region of 8/10 people are not happy with them heating their space heating. I have never installed one for space heating but am very interested in them for dhw.
My own thoughts on why they can have poor performance & high bills is due to poorly insulated homes so high heat loss results in pump difficulty in keeping up with the demand required.
If this is true, then for dhw it should be much easier to achieve due to factory set conditions, such as factory insulation, factory settings, controls, etc.
Am I on the right track or miles away?

No you're miles off. The problem lies in the fact there are probably 3 -5 decent installers in Ireland. Too many guys who know nothing about the workings of a refrigeration system installing them and using their own "philosophy" on how they should be installed. There is a very specific way a heat pump must be installed in order to get results.

Unfortunately most people don't even know the problems they create with their own takes on how the systems should be installed. That goes for distributors too, very very poor knowledge all round. The litmus test for any installer or salesman is if you open the magic box and something is seriously wrong with it could you diagnose and fix it. The answer to that is invariably no. At least you'll admit you know nothing about them and so avoid them. Not everyone is so honest. They don't offer any real savings over oil in hot water production only.

The amount of crap I've fixed over the years is unreal. I've managed to get heat pumps that cost €15 a day down to €4. Not as good as they could have been but you can't make a complete silk purse out of a sows ear. Most problems with underperforming heat pumps are fixable to a degree, the problem is the next guy you call out is invariably as clueless as the guy who installed it.

shane0007

Thanks I appreciate that.
If you are ever stuck for some work, I could refer you to lots.
I have one case where they are in the house (4,500sqft) just over 3 years & their electricity bill has been €34,500 since moving in. On average €2,000 per 2 months!
Their first pump never switched off. Told to replace it with a €25k 3 phase heat pump which they did. Heat but bills through the roof. Installer told then their electricity was leaking! ESB inspected & said nonsense & told them to turn off the heat pump & heat the buffer with immersion. That bill was €300 for 2 summer months incl lighting.
I was called in to convert to LPG but every UFH loop is open circuit & not one stat in the house. I am reluctant to get them to invest more without knowing the facts or getting more qualified advice.

QBE

Condenser wrote: »

No you're miles off. The problem lies in the fact there are probably 3 -5 decent installers in Ireland. Too many guys who know nothing about the workings of a refrigeration system installing them and using their own "philosophy" on how they should be installed. .

priceless response. You are bang on that button.

Condenser

shane0007 wrote: »

Thanks I appreciate that.
If you are ever stuck for some work, I could refer you to lots.
I have one case where they are in the house (4,500sqft) just over 3 years & their electricity bill has been €34,500 since moving in. On average €2,000 per 2 months!
Their first pump never switched off. Told to replace it with a €25k 3 phase heat pump which they did. Heat but bills through the roof. Installer told then their electricity was leaking! ESB inspected & said nonsense & told them to turn off the heat pump & heat the buffer with immersion. That bill was €300 for 2 summer months incl lighting.
I was called in to convert to LPG but every UFH loop is open circuit & not one stat in the house. I am reluctant to get them to invest more without knowing the facts or getting more qualified advice.

All loops open and no stats is fine (actually the best way) if the system is properly weather compensated but alot of control systems are poor. No weather comp or a poor one and its a disaster.
The issues lie elsewhere, what are the loop length and spacings? What temp is it being run to? Is it heating DHW and UFH to one set point temp or worse still to one buffer? Temperature returning from the lawn? Should be above zero but an undersized loop or one installed in incorrect ground conditions will lead to low return temps, low energy output and high energy consumption? Start there are then you can get into the more obscure reasons.

shane0007

Condenser wrote: »

All loops open and no stats is fine (actually the best way) if the system is properly weather compensated but alot of control systems are poor. No weather comp or a poor one and its a disaster.
The issues lie elsewhere, what are the loop length and spacings? What temp is it being run to? Is it heating DHW and UFH to one set point temp or worse still to one buffer? Temperature returning from the lawn? Should be above zero but an undersized loop or one installed in incorrect ground conditions will lead to low return temps, low energy output and high energy consumption? Start there are then you can get into the more obscure reasons.

I did not get into the specifics of the heat pump side as I would not have been in a position to recognise a horror or a hum dinger. They were adamant to rip the whole thing out. The system is heating one buffer with a built in DHW coil. They have been left with no technical details of the UFH loops. The installation company has left them abandoned & was one of the well known troublesome installations.

Condenser

shane0007 wrote: »

I did not get into the specifics of the heat pump side as I would not have been in a position to recognise a horror or a hum dinger. They were adamant to rip the whole thing out. The system is heating one buffer with a built in DHW coil. They have been left with no technical details of the UFH loops. The installation company has left them abandoned & was one of the well known troublesome installations.

Is all going through that tank? If so then theres your main problem. And its a fairly simple fix. It'll cut the bills in half if not more.
No doubt there'll be other issues but thats a huge one if thats the case.

shane0007

Yes all going through the buffer.

Condenser

shane0007 wrote: »

Yes all going through the buffer.

Disaster. The clueless goons strike again. Probably the worst thing you could do to a heat pump.

shane0007

What's the issue for HP's going through a buffer? I am so glad I am not one of those clueless goons who installed one, lol! I am just one that didn't!
Buffers & UFH work great together with oil.