Heat Pump.

davezawadi (David Stone): 
 

Peter, several times you have been asked to provide evidence for your assertion of dangerous “climate change”, that you are obviously considering to be warming.

I have given it, many times. Start out with the recent IPCC WG1 TS. If that is too much, try John Houghton's textbook (Fifth Edition, 2015). For less intense reading, try the Nobel Commitee's commentary on the 2021 Nobel Prize awarded to Manabe and Hasselmann.

 I have posted a very well-respected Professor of Physics telling you why you are wrong on another thread. 

I have my own colleagues who are “very well-respected Professor[s] of Physics”. I don't think any of them think global warming caused by anthropogenic greenhouse-gas emissions is not taking place. There is even one in Hamburg (not an acquaintance, though) who just one the Nobel Prize for work that others have used to “prove” (the Nobel Committee's word) that such change is taking place.

 

I would like you to tell us where he is wrong, which piece of physics is incorrect and why the basis of thermodynamics is being misunderstood. If you are unable to do this I suggest you provide an apology to the other posters, because the “Guff” is from you and not us. 

That is, unless I do what you say, it somehow follows that I am talking Guff. That is a non sequitur.

You made a long series of statements that (I take it) you consider show AGW due to anthropogenic greenhouse-gas emissions (AGGE) not to be occurring. I called those “Guff”. You mentioned the Mauna Loa measurements twice, and suggested they should be showing a reduction in CO2 in 2020. I asked you straight out what you think that reduction should be. 

Now, that is a piece of actual climate science. You haven't answered. I conclude that that is because you can't. (I can.)

What you appear to be good at is finding contrarian videos and WWW sites and saying “look at this!" “and this!" “and this!”. You are farming these WWW sites for statements that you think show that AGW due to AGGE is not happening. 

And then, you use what I call the “football fan” style of argument to try to suggest that these statements you pick up are right, and the IPCC WG1 TS/Houghton/Nobel committee are wrong. That style of argument doesn't convince me. 

You tried to lecture me on “Scientific Method”. You even tried to lecture me on the Standard Model of particle physics. What you decline to do is discuss climate science. 

I am thus lacking any indication that you are at all competent to discuss climate science. You are welcome to carry on cheering your “team”, but until you can get into discussing climate science, I don't see that I have much more to say.

Gideon: 
 

Hey, you guys had a perfectly good thread elsewhere in which to chase each other's climate change tails.

Quit hijacking this thread, it's about heat pumps, isn't it? 

Yes, I sympathise strongly. 

Gideon: 
……  it's about heat pumps, isn't it? 

So, back to the topic.

I first looked at geothermal heating 15 years ago. The conclusion is that it would not work for my building unless (a) I insulated it completely and (b) I installed completely new heating circuits. I have been through that in previous posts.

I just looked up the current situation, since I'll probably need a new heater in at most 5 years. 

The typical installation has the circuit to a depth of about 100m. Then there are heat exchangers in the house. However, typical temperatures are 35°C and my current system needs 50° or so. Underfloor heating is recommended. That would be impractical for me to install.

Installation cost is said to be €17K-€19K, up to the exchanger I take it. That is less than it was. I read that maintenance costs are negligible, but they certainly weren't 15 years ago, in particular concerning keeping the probe in working condition. It is going to depend on the local subsurface morphology and dynamics.

The energy is said to come about ¼ from the electricity needed to operate the exchanger and pump inside the house, and ¾ from the earth warmth.  I don't know how accurate that is.

There is another system, which I didn't know about 15 years ago and would be impractical for me, because I don't have a field. Apparently you can install flat collectors some 1-2m below the surface and they pick up the solar heating of the surface layer. But you need a lot of land……

Underfloor heating in a heat pump context seems to mean heated water tubes under the floor?

What floors does it work with? We have suspended wooden floors with a void underneath. One could insulate heavily underneath, but the heat would still have to fight its way past floorboards, underlay, carpet, which are themselves quite good insulation.

And, one might then have a 20-30cm impermeable layer, which would almost certainly lead at some point to damage to structure from trapped moisture. 

We don't have a first floor, but if we did… the heat would have to fight its way up.

I'm not sure I see how that specific aspect can be retrofitted to maybe most UK older buildings?

There is I suppose room under the ground floor for warm air ducts, but that's not ever suggested in UK, AFAIK? 

Gideon: 
 

Underfloor heating in a heat pump context seems to mean heated water tubes under the floor?

What floors does it work with? 

Here in Germany, it is laid in screed over concrete.

We have suspended wooden floors with a void underneath. 

So do I, in the main building. 

I can't see how it would work as well. The point of the layout in the screed is to warm it up more-or-less uniformly, conductively. If you have wood-on-stays then it is air, even if rockwooled. 

My attached building is 1960's and has screed-on-concrete. But radiative heating. Installing underfloor heating means new floors. I've been into the costs and I can't see it working out.

There is I suppose room under the ground floor for warm air ducts, but that's not ever suggested in UK, AFAIK? 

Andy C and then, more extensively, Denis McM introduced this on the “Electric Heatpumps” thread. Synopsis: installing ducted air heating/exchange does cost real money. I haven't costed it for my entire house, although I did discuss it in depth with an installation engineer in September 2020 when I was trying to figure out how to get 6 ACH in my music room (80 m^3) to give us space to practice indoors with flutes (result: too much money. A 500 m^3/hour UV-C disinfectant device would have been cheaper at €5K).