Ep42: Thomas Nowak 'Pumping Heat'

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Michael Liebreich: Before we start, if you're enjoying these conversations, please make sure that you like or subscribe to Cleaning Up, it really helps other people to find us. Cleaning Up is brought to you by the Liebreich Foundation and the Gilardini Foundation. Hello, my name is Michael Liebreich, and this is Cleaning Up. Now in the last few weeks on Cleaning Up, we've had Tony Blair, we've had Naoko Ishii, who used to be the chair and CEO of the Global Environment Facility of the UN. We've had Sharan Burrow, General Secretary of the International Trade Union Confederation. But this week, we're moving away from the policymakers, from civic society and we're doing a deep dive into the technology. Thomas Nowak is Secretary General of the European Heat Pump Association. Please welcome to Cleaning Up, Thomas Nowak. So, Thomas, welcome to Cleaning Up and I hope you've got yourself a beer or a glass of wine there because it's evening here in Europe, and I certainly do.

Thomas Nowak: Hi, Michael, it’s good to be here. Yes, indeed, I brought my favorite glass of wine here. It's a Blonde de Noir. It's the mix of dark grapes and white wine. So that's my pick of the last year that I found in Corona pandemic.

ML: It's a great pleasure to have you here on Cleaning Up. I've been looking forward to it for so long because we have a range of different people. Last week, we had Tony Blair. But we also do get to geek out, we get to wonk out every so often. And so, I've been looking forward to this. I've got my Fermi's Thermodynamics, should we need to refer to it. Because we're going to be talking about heat pumps, very topical, in the news. How do we get to net zero decarbonized heating. And before we get started, I'd like to say, cheers, I've got my beer because it's evening here in Europe, we're allowed to have a drink. So we really make sure we enjoy this conversation. And of course, we've got to start, I'm sure you're prepared for this with what is a heat pump? How does it work? How does it get? There's this heat is outdoors and then you bring the heat indoors, and it pumps it around and it makes magic energy. How does it work?

TN: I'm very happy to be here. And to answer that question. First, let me do it in a way that I did it in front of the fourth grade when my daughter was in primary school about to finish, it's two effects that you need to understand. One is evaporation, one is compression. Evaporation is you jump into a pool, you come out wind blows over your skin, you feel cold, the wind evaporates the water, then you take a bicycle and you have to compress the gas. So, the wind evaporates the water, now we if we could catch it again, and we would put it into a bicycle pump, we could pump, pump, pump, then you could touch the tip of the bicycle pump and it would get warm. So now the skin is your one heat exchanger and the tip of the bicycle pump is your second heat exchanger. And now you have to make sure that you bring in the energy from the outside, from the first heat exchanger into the house via the second heat exchanger, that's how it works. And it works very reliable. Yeah.

ML:Okay, so the cycle of the fluid is you pump, you compress it, it gets warm, and you put that indoors, so it heats up your room, and then you let it expand outdoors and it gets cold, but it evaporates but inside its tubes, it doesn't evaporate off, it in evaporates gets cold, and then absorbs heat from the outdoors. Even if the outdoors is quite cold, it can still manage to do that. You just repeat that cycle. So, it's really just a bunch of pipes, heat exchangers, pumps, I mean, what does one of these things look like? Because a lot of people out there, they just don't even know what it looks like. They don't know what to expect. If you said I'm going to show you one, they wouldn't know what to look at.

TN: If we talk about standard heat pumps for house use, used for residential heating, they would pretty much look like a fridge. They have the footprint of a fridge 60 by 60 or 65 by 65, something like that. Maybe they are 140 cm high, maybe they are two meters high, depending on if they have a hot water tank included or not. That's how they look like from the outside. So you wouldn't know. They can of course become much bigger. But in principle, you're right. It's two heat exchangers. It's a compressor. It's an expansion valve. It's a looking glass, some pipes and of course the refrigerant and that's important because, as you said it may be cold from a human perspective outside. But from a refrigerant perspective, it's super warm, it's absolutely warm enough to evaporate. And that's where you get the energy from and this is 3 or 4 Kelvin, that's enough maybe sometimes 10, and then you compress it to a higher temperature. So then you make the energy useful,

ML: Okay. And for a lot of people, they probably sort of at some point ended up around the back of a restaurant and they’ve probably seen heat pumps without even realizing it's a heat pump or maybe looking down on the roofs in New York, or wherever you see air conditioning units, it's essentially just variants of that, right?

TN: Absolutely true. I may say, however, that if you see these devices on the outside, then they are the result of cooling needs, quite often. And then you could also say, you're seeing waste of energy happening, you know, you can watch how energy is wasted, because in most cases, they are not used in a way that you would make use of that waste heat, you need the cooling, you have the heat for free. And instead of using it, for example, for hot water production for the kitchen, or if you ever own a hotel, you want to heat the pool. No, you're not doing that. You could use the European Parliament, they have 24/7 cooling requirements. And they have three big gas boilers in the basement for hot water production. If they had done a bit smart connection of the heat exchanger on the roof, with the energy demand, the heating demand, the hot water demand in their basement, they could have saved tremendous amounts of energy.

ML: Okay, so let's talk about some of the advantages. Before we get onto the fact that it can do heating and cooling. Right, let's talk about the efficiency. Because you know, I use the word magic energy. I mean, it just seems like it breaks the law of energy you put in, you've got one unit of electricity, but you get three or four units of heating. I mean how can that possibly be?

TN: Yeah, and now we should turn around and look at your Fermi, because he has for sure explained it very thoroughly. We shouldn't talk about percentages, in this case, we should really talk about factors because what is happening is you take one unit of electricity and then you, not magically but by physics, by thermodynamics, you take from the outside, and from the compression effect three to four units of heat, and then they then you can disseminate them into the building. So, we are not really creating energy. That's not possible, as you certainly know. But we are using the energy from the compressor electricity and from the ambient, and we combine the two, and that brings us to a higher level.

ML: So we are doing work. I mean, it's almost like we're using the electricity to simply move heat around. I mean, you could almost call it a heat pump, right?

TN: Yes, if you wouldn't be really smart and ingenious, you could do that.

ML: Amazing. Amazing, amazing. Great. And so the efficiency, I mean, the first advantage is that one unit of electricity, if you put it into a resistive heating element, just the sort of thing that we used to have in the bottom of the kettle, you put one unit of electricity in and you get one unit of heat. But if you could use it in a heat pump, you could get a factor of 2,3, 4 or even more in terms of effective heating for your space.

TN: I checked back with my experts this afternoon, because you asked me to bring a lot of fundamental numbers, substantial numbers. And what we can say today is that if with the heat pump in a renovation project, you can probably get an efficiency, or I shouldn't say that actually the factor of three. So one unit of electricity gives us three units of heat, if you built a new house, you should end up somewhere at 4.5, maybe even five, the best things I have seen, but then really, really optimized buildings that were optimized towards the heat pumps, then you can even go to six, sometimes seven, but then you only do heating. So, it’s a function in the end of the delta T, the difference between the temperature of the energy source, and the energy that you need in the house.

ML: I feel like I have a ghost on my shoulder because I have Fermi there. But you're right, because if your delta T, now that is the difference in the temperature between your heat sink in other words outside or outside and the temperature in your building, and if you can run your radiators at a very low temperature, if you have to heat them up to a high temperature 70 degrees it'll be very inefficient, but if you can use underfloor heating maybe and you can run your fluid at I don't know 28, 30, 35 degrees it's going to be much, much more efficient, right?

TN: That's true but it's now technical progress has led us to a situation where we can say 55 degrees, 60 degrees is absolutely feasible and also efficiently feasible. So, we are not in the situation that in the past where you would say okay before I can even consider a heat pump, I need to rip out all the radiators put floor heating and insulate the house, I will not be able to live in this place for four weeks or longer. No this is actually now, recent developments make the heat pump suitable for direct replacement. Of course, you need an expert to look at this I wouldn't recommend for you to do it yourself.

ML: Right. And I think that's one of the things that the heat pump sector carries a lot of baggage. There's a lots of sort of misconceptions, partly because historically, they weren't very efficient. And maybe they were noisy. And maybe if you wanted to use one, you would have to replace your radiators because the working temperature was so low, if your radiators, you're used to running them at 60 degrees and suddenly you come along and say, well, we can only get to 40 degrees, you need bigger radiators. Yeah. So, there's a lot of these things that perhaps were true in the past. I don't know.

TN: I mean, it's really a design question. So sometimes you may need one bigger radiator or two bigger radiators, but most of your radiators will be okay. And that's why I'm saying we need… the problem that we have at the moment is if you want to put the heat pump in, you need to have a little bit more knowledge than just replacing the existing boiler with a new boiler. And for that, we need some experts, they are available, but sometimes people are not willing to pay for that. So therefore, let's say this trap of somebody coming by the house saying, oh, I have a cheap solution for you and now you can just go ahead.

ML: Okay, but let's stick with the advantages first, we'll get onto… I think Winston Churchill said, “don't bring me the problems, the problems will speak for themselves.” So, let's get on to that in a bit. But let's talk about the advantages. We've got the advantage of efficiency, you've got the advantage that they use electricity, which is much easier to decarbonize. If you're heating with gas, then I suppose you can go to biogas, you could maybe go to hydrogen, but you can go to clean electricity right. Now, what about air quality? What about some other things that this technology enables us to do?

TN: I mean, in the past, I would say we have we have a triple dividend, right? We have we use renewable energy, we do this in a very efficient manner. And we reduce CO2 emissions. Now we can add to that, that the heat pump by its design can also balance the electric grid. So actually, more heat pumps are not a problem for the grid. They're a solution because they can shift demand. And they can shift demand, probably about 24 hours or even more, depending on the design again of the system. They also have no emissions, CO2 emissions and particulate matter, because that's also a problem in some areas of Europe and of the world that you don't want particulate matter at the point of operation. They, what I find quite important, they use local, local available energy so you don't have to import the fuel to run them. And they provide local jobs. So all these things together, you would say, some people say is that the panacea. Maybe it's the panacea, it has so many benefits. And if you choose to buy a green electricity tariff, then you have 100%, emission-free and green and renewable energy solution today.

ML: And I'm smiling at this, the panacea, because there's a fabulous podcast, you probably have heard it called BetaTeach. Yeah. And Nathan always says on this, he says there's no actually he jokes, he says there's no panna cotta, there's no panacea. And other situations where a heat pump just doesn't work in other buildings, where you just say, just this is not the solution.

TN: Now I will quote this Churchill that you mentioned, start with the good things first. They do work in all new buildings, and they perfectly work in on your new buildings. They do work in all renovated buildings that have gone to a level where you would say they are very similar to new buildings, they also run in buildings that are optimized by Nathan and his colleagues, because these guys are really smart. And I advise everybody to listen to this BetaTalk. It's a really very thoughtful podcast, different than yours, so it's really complimentary, I would say. And then they also work in residential and commercial buildings that have the same qualities. Where do they not work? And that's indeed the question that you were asking. And I would say, if you find a tent, it's not a good idea to put a heat pump in. If you find a building that that has the energetic qualities as a tent where you can feel the air moving through. You don't want to heat pump air before until you before you have done some renovations. But every building that is halfway good, and the old rule of thumb says if you can heat the building at around 55 degrees and you can check that because the boiler has a <inaudible> thermometer go down in the cold day in winter check if your radiators running 55 degrees if that’s the case the building is ready for heat pump.

ML:

Okay, and this point about the circulating temperature for your heating is incredibly important. And I'm really embarrassed. I did a big renovation of my house, very innovative. I've got a heat pump, I've got solar, I've got a fuel cell, I've got passive ventilation. And at no point did I ask the question or look into you know what temperature the actual heating circuit runs at, and to this day, I've got no idea what it runs at. I know I've got underfloor heating, so I'm assuming it's fairly low. But it's very important, isn't it? I mean, it decides the whether you can use a heat pump and how efficient it's going to be.

TN: Yes, both totally true.

ML: And I learned this from Nathan from BetaTeach, the lower the temperature of the heating circuit, the more efficient…and by the way, the lower, the less corrosion and all sorts of benefits. I have a thermodynamics prize from Cambridge, but that's what I learned from Nathan.

TN: Yeah, but some things are practical and you need the experience. And that's really the point, you need some experience to guide people through the renovation process.

ML: And that brings me to, you know, we do have to talk about why is it if these things are so fabulous, you do get this multiplier, this coefficient of performance, the multiplier factor of, you know, energy, and they're so much better from air quality perspective, and most buildings that could be heated at a reasonable temperature could, you know, would be fine. Why is it that we are doing anything else? Why are we having this conversation? Isn't this so darn obvious?

TN: Yeah. But it's still not the dominant solution. I mean, we are looking at a situation if I look at European numbers, 75% of all buildings are still heated by fossil energy. And you could say that wouldn't be a problem in the first place if these fossil energy would not emit CO2 while burning it. So you know, if you could have that come completely clean, no problem, but it is not. And that's why.

ML: Okay, but so 75% of buildings, even new buildings, is that right?

TN: I think in new buildings, it's more like 50%, we have made a study recently, where I'm in most European countries that we have looked at, and now we have only looked at 10, but the heat pump is the number one technology in new building. So, we see a considerable shift happening as we speak.

ML: Okay, but it's not universal. And okay. I mean, we could rule out one potential explanation, which is that the European Heat Pump Association has been run by somebody who doesn't know what he's doing, right? It's not that, that we can tell is not the case. So, there must be something else going on. Why has it not caught on? Why has it not become universal? And I would argue one of the real problems is just familiarity and the skills not just amongst the consumers, consumers don't know what a heat pump is, but also amongst the installers. Am I being unfair on installers?

TN: Well, I would say typically, installers know very well what is good for them. Let's start like that. I think also installers are quite capable of installing different types of heating solution. So, we will probably not have a shortage of installers even if we have more heat pumps because they can shift their knowledge, they can use education offerings that are available. And I would agree. There is a bit of a shortage of understanding, but not only with the decision makers, the end user decision makers, but also with policymakers. I had to go through a list of critical of obstacles where people would say heat pumps don't work at all, that was the first one, heat pumps don't work when you use air as energy source. You cannot imagine how long we had to debate whether or not heat pumps were okay if they use air…

ML: When you say used air, you mean air source heat pumps…

TN: Air source heat pumps. Exactly, exactly. So then that then people say, no only new buildings, then they said, okay, single family houses only but not multifamily, then the discussion was around the industrial applications. Now we have ended up at a situation where people say okay, but they are too expensive. So, of course, the opponents say that they are they are too expensive, it's expensive, and they will break the electric grid. So, if you ever have your millions of heat pumps, Thomas, that you talk about all the time, then we will have sudden blackouts of tremendous magnitude.

ML: And why would that be? Why would that be?

TN: Yeah, it's not going to happen.

ML: It’s not going to happen. I agree. But why? Why is it plausible? Why does that argument have what you can call truthiness? Why does it resonate with people?

TN: It's built on this idea that people say okay, the heat pump is losing capacity when it's getting really cold, you need more electricity, grids are not made for that electricity is under then they will fail. And then they say look at Texas.

ML: So this coefficient of performance, this magic free energy, it's less when the temperature drops, correct.

TN: Also capacity goes down.

ML: We have this thing in the UK called the Beast from the East. Normally our weather comes from the west, and we've got the Gulf Stream and you know, that keeps us warmer than otherwise. But every so often it licks around and we get the weather straight from Siberia, the Beast from the East, and you can get this dramatic fast… You know, within a couple of days, you suddenly get these huge temperature drops. And it can be 3, 4, 5, 6 days, really cold. Yeah, it only happens once every 3 ,4 ,5 years. But if you can't heat the homes during the Beast from the East, then a lot of pensioners will die. Because they will get hypothermic, their homes are not well insulated, and will have terrible mortality potentially. So, what happens if the grid… you know, we say that the grid will be able to cope with this. How sure can we be?

TN: Well, probably, we have to talk to a grid expert for that one. And then that wouldn't be me. But the people that I've talked to, the experts that that I have talked to, they say, first of all, you will not have these millions of heat pumps from today to tomorrow. So, we have 10 years, 20 years to accommodate the grids for that. And we know how to do that we have done it in the past, we can do it again in the future, then maybe as a side effect, we are looking at electromobility at the moment, so the grids will be reinforced to completely different numbers than we have them today. And I mean, let's look at what happens really, if it would get cold from today to tomorrow, I think three-four days is already an adjustment period. That is quite long. In grid management terms, again, saying I'm repeating what I've heard from some experts, but if it would happen very fast, the heat pump is not dropping out, the heat pumps operate at minus 10, minus 15 degrees centigrade, they are not operating at the same efficiency, but they are still operating. So, it would not be that that your elderly people that you mentioned would just freeze inside their home, I'm sure that they could accommodate in order to survive, right? If we make up a really nasty scenario, then you may be heat only one room, then you put on another sweater you would not die and the house would not cooled down to minus degrees, it would mean not be as comfortable as 24, but maybe you could handle a temperature that was too comfortable for you.

ML: What I'm hearing is that there are issues that at the very least require number one planning and number two investment. I mean, the grid as it stands today could not cope with millions of heat pumps in any European country. Correct?

TN: I would say if we talk about France or Sweden, countries that by tradition, have very strong and strong focus on electric heating and experience, maybe they can I again, I wouldn't… This is not what we are looking at every day, but many countries will not for sure. Yes.

ML: Okay. So and, you know, that really raises the question of Okay, so I, you know, and obviously, look, I'm a big believer in electrification of pretty much everything, including heating, so I'm playing devil's advocate here. But you can see that it does require investment. And when we talk about the investment in the grid, it's not just generating more electricity, but you have to get it into every single street. So, it's the distribution grids, and it's lots more generation, the transmission grid and the distribution grid are probably going to have to dramatically increase in capacity. If we go with heat pumps, and particularly if we have to, if we go with heat pumps and electric transport, surely we're I mean, that seems like we're going to have to do a lot of investing.

TN: Yeah, that's for sure. True. But you mentioned, luckily, you mentioned the electric transport, because and then you mentioned before, why are people not doing it faster, we think that the electric transport will require, will demand more of this of this attention. And that will also result in an upgrade of the electric grid that that is seen as absolutely necessary. Because electric transport is so visible, you buy an electric car, your neighbours see it, you buy a heat pump, nobody sees that maybe one of the reasons why it's not so you know, in your peer group is not so known what type of heating you have. But it's very known if you have a very nice new car. But then the investment needs to happen. And what I found quite surprising when I heard it first was that this investment, if it's properly planned, is actually not such a huge amount of investment that is necessary there because the grid buildup is done from top to bottom. So, if you if you start to build up a certain part of the grid, you put one big transformer there, but then you can take all the other transformers that were there and move them one step down one level down. So, in the end, it's not as you would imagine a rebuild of the whole grid. It's really an upgrade, in part where it's necessary. There are quite good simulation tools that allow you to understand where which upgrade is necessary.

ML: Okay, but I've got you to the point you sort of admitted that, yes, we're going to need to upgrade the grid, there are some costs further in the system. And the reason I kind of lured you into admitting that is because of course the opponents of heat pumps, of this wonderful technology, they would say, well, we should just be using hydrogen because in most of Northern Europe, particularly in the UK, we already have pipelines, we have gas distribution networks to every home, this is crazy to be doing this complicated thing with these, these heat pumps, this clever stuff, whatever. What we should do is simply pump hydrogen through these pipes, change the burners, maybe the boilers, but that's relatively, you know, feasible. We've done it before, when we switched from town gas to natural gas. And, you know, as you say, nobody knows, nobody cares what technology they use, they're addicted to warm houses, but they don't care whether it's heated this way or that way. Why are we doing this complicated thing with lots of expensive investment, when we could do something much simpler, and that's the argument of the hydrogen promoters.

TN: Let me say that I'm not so sure that it's going to be much simpler. But the argument that I find is more important is that if you go for the heat pump road, you also offer the people a more comfortable life afterwards. Because if your argument is let's not invest into the building core, let's simply replace the boiler, that means the building stock stays where it is. And I have frozen at dinners in Edinburgh, in London, you know, the UK has this notoriously bad building stock. It's not like your house, it's these houses where you maybe you managed to heat one room to 22 degrees, but not every room. And so, if you if you do not touch that point, you will still have a warm room, that's fine. But I think if you look at the whole building, and optimize that, and then make it ready for heat pumps, you could say that's a byproduct, but you give people a more comfortable life. And you contribute to better indoor air quality and outdoor air quality because you avoid the emissions that are coming from combustion.

ML: But couldn't I argue that well, maybe we should upgrade the building stock, right? But why not upgrade the building stock and then use hydrogen?

TN: You could argue that, it's argued quite often. But then the question is, is the is the grid ready for hydrogen as we speak, So, will this go without any further investment. And then I would say if I made the effort to build to upgrade the building, and then I move into a full electric road, and I know that the technology is here, then personally and now you would say well Thomas, you have to say that but I live in such a house, it is really comfortable. I used to show photos of the bare feet of my daughter when she was just running around because it was so comfortable in winter, you know, snow outside, barefoot indoors, because it's possible. It's more comfort that I stand with that, because I've experienced it myself.

ML: I hear all of that I what I want you to be talking about actually is how much hydrogen you need. If you go that route, and then maybe I should get somebody in who's a hydrogen booster. And then I could challenge them. And I should say yes, where's the hydrogen going to come from?

TN: And I will come I will come back then. Well, let me first say one more thing before that, because we mentioned the Beast from the East. What we have calculated is that if you if you look at the efficiency improvement of heat pumps and the energy demand for heat, you probably have to double the amount of electricity that you have to provide to end users over the year. So, it's not this factor of 3,5, 7 it’s not such a drama, it's actually quite modest, I would say. Then, how much hydrogen we need, I don't know, I would say we need the hydrogen in a systems perspective, because if this Beast from the East is coming, and I would have some stored hydrogen somewhere, I could happily burn it in CHP plants, for example, provide the waste heat to district heating, provide electricity to then have a stable electricity grid that is feeding a lot of electric vehicles and heat pumps. So, in this, you know, I think we need a system for sector, we shouldn't look at only the individual building where we can make it very easy for the individual user.

ML: Listen, you won't find me disagreeing. I think that, first of all, I do think that hydrogen could play a very important role in stabilizing the grid once we move to a very deep penetration of variable renewables, and particularly in those kind of Beast from the East conditions. But if you gave it to me, I'd probably burn it centrally and use the electricity. The last thing I'd want to do is put it into cars, or put it into every heating gas network at that point. So, I agree with you, again, just playing devil's advocate because it's a very, very live debate right now. And there is a big pushback from people saying, well, they want something simpler, of course, you know, at the end of the day, if you're talking about hydrogen produced from electricity, then what you're doing is producing it, throwing away 30, 40 50% of the energy to you know, during that process of electrolysis, instead of putting it into a heat pump and getting that coefficient of performance of 2, 3, 4 or 5,  and you said even up to 6, so it's just a… You need a lot more offshore wind farms if you want to go with hydrogen heating, and I'm not sure that people realize that.

TN: Well, I think it's not it's not even debated that the efficiency, if we do efficiency first as it has been stressed repeatedly also on the European level, then the heat pump is number one, we have eco design that shows very clearly by all standards, that this is one of the most efficient, if not the most efficient heating and cooling solution available. So, if we want to follow that principle, then we should focus on heat pumps. And if there is areas left where heat pumps can't work and can't deliver, then we will still need other solutions. I'm not saying that heat pumps can do everything. I mean, we are having other solutions that should be used. But I think it's a good rule of thumb to say we have 75% fossil heating today. Let's aim for 75% heat pumps by 2050.

ML: I would say that that's far too low, I think you should be aiming higher. You're not ambitious enough. And the reason I want to talk about a couple of other things. So, one is we're not only talking about homes, we're talking about commercial buildings we're talking about, you could use a heat pump to drive district heating, and of course, industry. A lot of industry uses heat up to…what sort of temperatures can a heat pump deliver?

TN: Yeah, that's a beautiful topic. I've burned my hand nearly because an expert's stopped me from doing so at 140 degrees delivered from a heat pump. And that standard, that was in a project test site.

ML: And for the Americans, that would be 140 degrees centigrade, right? Not Fahrenheit.

TN: Yes, 140 degrees Celsius. So that that is currently available, you can pretty much buy it off the shelf, maybe even up to 160 degrees. Colleagues of mine are working at heat pumps now trying to make 10 bars of steam and 180 degrees. So, the big discussion is the paper industry ready, right. And that's the typical solution that would help the paper industry to decarbonize. And in Japan, they have a project now running that says 200 degrees should be the limit, some experts tell me maybe even 300 but then we don't have good enough lubricants for that. So, you know, there's side effects that have nothing to do with the heat pump technology. But so just to categories that, below 100 is absolutely a no brainer. So, if you have temperature requirements below 100 degrees centigrade, heat pumps are your solution. 110, 120, 130, 140, you will find solutions, but it may be a bit more complicated above that. It's quite experimental beyond 200, I don't know any solution that runs there.

ML: Right. And I think that's really important. Because if you look at those sorts of temperatures, when you talk about 140 degrees, 160 degrees, 180 degrees, a lot of things, paper industry, food processing, you know, I was just astonished when I went down to New Zealand in 2019, and I found that 10% of the country's carbon footprint is from drying milk powder using coal. And I said this is crazy and it became a sort of almost like a frontpage headline, you know, British, UK energy expert says drying coal powder is insane, but it is insane, using coal and of course a heat pump at those temperatures: you could dry your milk, could you not?

TN: Yeah, I mean a dairy plant is really the standard solution that should have heat pumps in there. Actually, the big heat exchanger manufacturers Alfa Laval for example is that was the standard in the 1970s you would go to a farm you know, the all the farms had their small milk collection on site. And of course, they had to cool it and everybody had this Alfa Laval equipment though I think they even grew up in this farming industry.

ML: But that was cooling. So that was taking milk from 30 degrees down to five degrees or whatever. Yeah, now we're talking about to dry it to milk powder, you need to get to a probably 160 degrees, something like that, right?

TN: Absolutely. But if you have if you had the 30 degrees from the milk, you know, that would be such a perfect feed temperature for lifting the energy up then to then dry something with that. And you have you have…

ML: We need to go back to Fermi and ask whether the energy balance, whether there's enough milk at 30 to dry the rest of it to evaporate but that's a tough call. But, you know, that doesn't have to be that's not the only source of feed, feed warmth, feed heat, is it? I mean you could use a river or air or whatever.

TN: Now what is this a very good one we have at the HPA we have this heat pump award and last year we gave it one of the categories went to Tine in Bergen in Norway, and they pretty much remodeled the whole dairy plant to make it a closed energy cycle. Not completely closed, but very close.

ML: So temperatures up 140, 150, 160 eventually probably above 200 we could solve them. I'm sure we can solve the lubricant question. There’s one other area that I want to talk about is… there's some great innovative projects and at least they’re portrayed as innovative. Star Renewables in Glasgow. I think it's in Glasgow. They're taking heat out of a river and then feeding it into district heating. Is that innovative? Is that? Is that cutting edge? Or is everybody doing it in Scandinavia o in Japan?

TN: I think it's… innovation, like beauty is in the eye of the beholder, right. So, it's difficult to say for whom it is innovative. If you usually have Dave Pearson, here. He's a great guy in talking about river energy. And so, from what he's doing, he knows very well that it works perfectly well and efficient. And you may say, it's maybe an innovation now for Glasgow, but they have one project running in Norway, and Drammen, and I visited it and the plant manager cannot get the smile off his face, because it's so economically interesting for them. It's, I think it's having the same success in front of itself. Also, in the UK, you see that we have water-based heat pumps in the big district heating systems in Scandinavia, in Gothenburg, in Sweden, in Stockholm…

ML: All you’re doing is taking the water out, removing some heat, and you put it back in a little bit cooler, a couple of few degrees colder, right? Power stations all over the world are taking water out and putting it back in hotter. And here you're just doing the opposite.

TN: From an ecological perspective, you could actually balance the temperatures after behind the power plant, right. So, you would not have to do the impact assessment for the power plant because you could say I could use the wasting from the power plant for my heat pump.

ML: I don’t think you need the river anymore. But that gets very technical. Yeah.

TN: That's very true. Now you do that another time. But the important point, why is that innovation here? And why does Dave has to fight for this <inaudible> from Star? Because the energy price is not the same, right? The electricity prices and prices for other energy carriers in Scandinavia have a completely different level than they have them in the United Kingdom. And you have asked, why are not more people doing it? And maybe this is one thing that we need to talk about? It is quite often the case that fossil energy is too cheap at the moment. People say heat pumps need to become cheaper. What you could say is that society is generously paying for the emissions of fossil energy heating, and heat pumps is just the price that you have to pay if you include the external effects.

ML: Yes, and that's certainly, you know, one of the one of the problems that we got, if there's any policymakers, you need to compare the taxation basis for heating with gas versus heating with a heat pump, because they can be completely different. The heat pump might be a higher capital cost, and there may be all sorts of taxes, VAT and so on, on them. And it's absurd, it's very unfair comparison. And actually, what we're doing fundamentally is subsidizing the use of fossil heat, I want to just, before we go, I want to just touch on one other area because we've not talked about ground source heat pumps, we've sort of talked most of what we've talked about, we talked a little bit about industry with different heat sources, but mostly we're talking about air, but ground source heat pumps, there are a number of different sorts are there not.

TN: I mean, technically speaking, you can have a closed loop or an open loop. So, you have a drilling where you have a closed brine cycle, or you use water from an aquifer, and then you have to bring that water back, that's actually the same as happening for the big district heating heat pumps where you need a lot of water. And so of course, water is a very, very good energy carrier. So, if you want huge capacities, you're very well off with the hydrothermal heat pump that uses the water as energy source. But of course, then if you if you want to hide everything, and it's it should move underground than this drilling to the bottom, that's very, very efficient.

ML: Right? But there's also very simple ones, which are just burying the heat loop not even very deep, right?

TN: Yeah, but you know, the principle again is pretty much always the same because we didn't talk about wastewater, sewage, you can do exactly the same. You take the same type of, of heat pump and you take whatever energy source you have, you can drill you can take a parking lot that is underground, you could take an underneath a river that is hidden beneath the city, you can take the subway.

ML: The subway, I was gonna say the London Underground which runs hot. We've got 150 years of heat that's in the clay down there.

TN: Yeah, and you could actually cool down the subway. I mean, if you imagine that the subway in summer is not a very pleasant place to be. So, if you could take the waste heat from the subway to heat your hot water and then you blow the cold air back down. Everybody would be super happy.

ML: When I was on the board of Transport for London, I'm pleased to say that we did push forwards a few of those projects. In fact, there are some. The complication tends to be where do you put the chillers? And how do you get the how do you how do you, you know, how do you vent to the air, you're in the city. But there is one innovation, which I like very much, which is shared loop, ground source heat pumps, because in the UK, if you're out in the countryside, very often the ground source heat pump where you sort of bury, you either drill down and, you know, fairly deeply, or you just bury a loop. And it works. But it's very often for an isolated house, a single house, but shared loop can be used for housing estates, can it not?

TN: Oh, absolutely. And I would say that this is probably the last generation of energy grids that we ever have, what we call neutral loops. And again, here, you imagine a big pipe, which is a big body of water in the end. If you would put that into a big circle, and you connect as many people as you want. And you have small heat pumps, then they are technically speaking, ground source heat pumps. But in reality, you just have this huge loop that is your energy source. Your aquifer, where if you want.

ML: So, let's clarify. So, you've got one big loop that circulates energy or water, at what sort of temperature?

TN: Oh, it can be at the ambient.

ML: Around 15 degrees, 10 degrees, whatever it comes. And then each individual home, pulls out some water, dumps, well, extracts the heat, dumps cold water back in, and off it goes around the loop. So, it ends up maybe after going around a housing estate, maybe it starts at 15 and ends up at 12. Or it ends up at 11. Right?

TN: Yeah. And of course, then then it's physics again. So, you need enough water flow enough volume to make, to deliver enough energy to every household. But that's a design question.

ML: And each house has a small heat pump. Yeah, right. Yeah. And I love this. It feels very elegant. And I can understand it working in a new build I think if I was building a whole new kind of housing, estate 5000 homes, I would definitely be using that approach. There's a great company in the UK, Kensa, I'm sure you know, Kensa, well.

TN: Yeh, I know them well. But I would say actually, if you use Kensa’s expertise for new buildings, no offence, maybe it's a bit wasted. Because what they can also do, and they have done really great projects for renovation, if you build this loop into the vertical, you can take the old chimneys for example for to put the water loops in there. And then you put a small heat pump into every apartment, then you're solving one of the big problems that we have today, the renovation of existing buildings, especially existing high rises.

ML: And where would you get the heat from, you'd have to go you'd have to ground <inaudible>, you still need a ground loop somewhere?

TN: You could say whatever. If you have this high rise next to a data centre, you take the data centre, if you have it next to sewer, you take the sewer, if you need to drill, you drill.

ML: Okay, listen, I was looking forward to this conversation, I said at the beginning, and it has not disappointed. I've gotten tremendously excited. Some of the audience will know that I'm a thermodynamics geek. That's what I studied. I absolutely love it. And so, I've really enjoyed this conversation. And you know, really, at this point, we're kind of out of time. And I'm going to thank you, though, for coming on to Cleaning Up. But also, for the work you do evangelizing on behalf of this extraordinary simple, miracle technology.

TN: Thank you very much. It was a pleasure to be here. And indeed, I can only say maybe you have felt this a little bit. I'm still amazed myself that there is a cycle out there, thermodynamics that allows you to provide heating and cooling at the same time. And I'm so happy that this is now recognized and we can make the most efficient solutions with this technology for mankind, you could say.

ML: And you know, you remind me that at the last minute, you reminded me that we haven't even talked about how you can actually run these cycles in reverse. And your heating which has kept you nice and warm all winter, can actually keep you cool during the summer. But to go into that in more detail we'll have to have you back on the program in due course.

TN: Well, thank you very much, Michael.

ML: A great pleasure. Thanks for joining us. So that was Thomas Nowak, the Secretary General of the European Heat Pump Association. My guest next week is Rhian-Mari Thomas, she's the CEO of the Green Finance Institute that was set up to drive more private money into climate solutions. And before that, she was the head of green banking at Barclays. Please join me at this time next week for a conversation with Rhian-Mari Thomas.