Hide Accessibility options

+44 (0)131 625 1011

Close this search box.
Podcast S13E08

Heat batteries, scaling up, and Sunamp

Heat pump outdoors on snowy landscape

In this episode, we’re looking at the topic of storing heat. As we use more renewable heat and electrify more heat, decoupling the timing of heat demand from when it’s produced is going to be more and more important. Jon is joined by two guests – Andrew Bissell, CEO of heat battery company Sunamp, and Klara Ottosson, Heating Business Research Service Manager at LCP Delta.

Episode transcript

[00:00:04.150] - Jon

Hello and welcome to the episode. Today we're looking at the topic of storing heat. Now, as we use more renewable heat and electrify more heat, then storage will become more important. And so we'll need to decouple when heat is produced from when heat is being used. There are quite a lot of ways to do this, but today we'll be focusing on heat batteries. I'm sure most listeners will be familiar with electric batteries, but you can also get heat batteries and specifically heat batteries using phase change material. And to explore this, I'm joined by two guests, Andrew Bissell, CEO of heat battery company Sunamp, and Klara Ottoson, one of our experts on the topic here at Delta-EE. So let's say hello. Andrew. Let's start with you.


[00:00:55.490] - Andrew

Hi. Very nice to be on the show.


[00:00:59.570] - Jon

Thanks, Andrew. Now, my guess is that some of our listeners won't have come across Sunamp before, and I'm sure you're excited to change that. Could you give a few facts and figures about Sunamp and a sort of headline description of the company to get us going?


[00:01:15.720] - Andrew

Sure. So about 15 years ago, I was exiting a medical imaging software company and choosing between a life on the beach relaxing or giving it another go at doing an entrepreneurial start up business.


[00:01:36.170] - Jon

And you didn't choose a life on the beach, did you?


[00:01:38.620] - Andrew

I didn't choose a life on the beach, but to be honest, the beach came into it. I was living in a house in Edinburgh at the seaside. A lot of people don't know that Edinburgh has a beautiful seaside with a beautiful two mile long beach or whatever it is in Portobello and Joppa. And I was looking at the water and thinking, what happens if there's a metre rise in sea level, which is what was projected as the outer limits of what happened under the climate change? The IPCC sort of consensus at the time, that motivated me to start Sunamp, and what that became was a company that focused very strongly into thermal energy storage in very compact form. So our view was that if we didn't solve the problem of how do we do thermal energy storage we would never stabilise the full energy system into a net zero system. If the products were too big, nobody would be able to put them in the homes people live in. No motivation.


[00:02:50.730] - Jon

So would you describe yourself as a developer or manufacturer or vendor or all of those?


[00:02:57.210] - Andrew

Yeah, we're all of those. In the early days, we were a developer of technology. We created some radical innovations that are patented now. Then we became a manufacturer because you have to be able to make them. And now we sell those products at scale. We're about 20,000 units into selling a thing that we would call a heat battery. We're fourth generation product now, the Thermino product.


[00:03:26.460] - Jon

Geography - so you still living in Edinburgh, but what's your international footprint?


[00:03:31.710] - Andrew

I still live in Edinburgh. The company is headquartered in the Edinburgh area and has its main factory here. But we're selling all over the world. We have a sister factory under licence in South Korea. We sell in China, we sell in Korea. We sell in multiple countries across Europe that will become much more intense over the next year. But already, for example, in the Netherlands, we sell with Flamco. They sell under their brand, a product that we developed for them. And we just opened an office in New York City to enter the US market.


[00:04:08.430] - Jon

Very exciting. And the last question in terms of facts and figures and who are Sunamp? Rough number of people? You said selling about 20,000 units a year or sold about 20,000 units in total. We're talking tens, hundreds, a few of tens of people?


[00:04:28.530] - Andrew

We're 60 or so people today. I mean, it is going up quite fast. About 15 of them are in the factory making the product. Maybe another 15 are in our materials and engineering teams developing the product, and then the rest are involved in all the functions around sales and administration that make it work on a commercial basis.


[00:04:58.710] - Jon

Okay. Thanks, Andrew. And I guess for the energy transition. Very pleased to hear that you're not sitting on a beach, but you're developing a crucial part of the transition.


[00:05:09.330] - Andrew

I hope that will work out well for everybody. I mean, certainly it's the only motivation that will keep you doing it.


[00:05:19.450] - Jon

Okay. Well, let's come back, Andrew, to you shortly. Say hello to our second guest, Klara Ottoson. Hello, Klara.


[00:05:25.650] - Klara

Hi, John.


[00:05:27.670] - Jon

Klara, can you contextualise heat batteries? How new are they? Is it a brand new innovation and how does it fit into the wider topic of thermal storage?.


[00:05:40.100] - Klara

Well, thermal storage ranges from very large scale interseasonal storage and gravel pits and aquifers. But then we also have residential storage in the form of inertia from the building and what we're all familiar with, hot water cylinders. Heat batteries belong to the residential applications of thermal storage, but are distinguished from traditional thermal stores like hot water cylinders, by the fact that they have a greater energy density and they're smart and can optimise the heat charging and discharging what we like to call advanced thermal storage. Heat batteries in residential applications is still a fairly small market, but we are seeing more propositions emerging from new and young companies.


[00:06:24.140] - Jon

Okay, so, yeah, thermal storage isn't a new topic, then. Many of us will have thermal storage in our homes through, as you say, a hot water tank.


[00:06:34.140] - Klara

Or just in the walls.

[00:06:38.140] - Jon

Yes. The inertia of the building, heat up your building and it stays warm even if you switch the heat. Okay. That's really helpful, the bit that's special about heat batteries, then, is the compactness.


[00:06:47.310] - Klara

Yeah, exactly. So that they have a higher energy density than water, which is the traditional thermal storage in buildings.


[00:06:55.200] - Jon

Yes. Andrew, anything else that's super special about heat batteries in addition to that density of storage, or is that really in a nutshell what makes heat batteries different?


[00:07:03.840] - Andrew

The way we make them, we also took a very, I think, bold decision very early on, which was we put vacuum insulation panel in the wall of the heat battery. That was quite an expensive decision at the time we did it. Over time, we've been able to crunch the cost down on that, but it means that we get an A+ rating on the European energy label and on the UK energy label as it is now. And that means that a product which would, if it was a hot water tank, B rated, lose 1.4 kilowatt hours per day of heat energy to the house, loses in our range 0.7 kilowatt hours per day. So we have roughly the heat loss compared with a good hot water cylinder. And we are about a quarter of the heat loss of an old cylinder, one with a sort of red jacket or a very thin layer of green insulation. That's 1000 kilowatt hours a year of energy saving.


[00:08:13.130] - Jon

So for a hot water tank, if our listeners have got one at home, they'll be familiar with it cooling down over many hours, days. An electric battery. People won't think of the electricity leaking away, not over hours and days anyway. So it's really very similar to an electric battery, except an electric battery you can charge and then discharge. I guess it's the same as an electric battery and it's just heat. You can charge the heat in the battery and then you can discharge it out to a heating system, to hot water, to whatever you want.


[00:08:48.810] - Andrew

It's really interesting. On a 24 hours cycle, we would be about 95% or so of the energy you put in you'll get back. And an electric battery is probably similar because it has losses going in and losses coming out. So I think you're absolutely right and it's probably one of the reasons we chose the term heat battery, although actually it turns out we weren't original in doing that. And I think it's really worth saying that we pay huge respect to the people that went before us, back to Maria Telcas, for example, in the 1940s in the US, who made the first heat batteries, and they were installed in a house that was commissioned by Amelia Peabody, the Dover Sunhouse, and they were really successful for a while. Unfortunately, the chemistry at the time wasn't good enough to keep them going for a long period. And the difference today is that we've been able to perfect the chemistry and we can make them last, I'm not going to say forever, but for 50,000 cycles, at least, that's 50 years worth of use or something like that. It's a very big differentiator from the beginning of this in the 40s, but it's great to know that we are building on that legacy of researchers over the years and we finally reached the commercialization point.


[00:10:25.130] - Jon

Andrew, Klara, I'd like to divide the discussion up into three parts and possibly slightly back to front. Firstly, the challenges of growing a company, Andrews, he described, and then secondly looking at the use cases. So how will heat batteries, how are they being used? How will they be used? Finally, it's a challenge of getting heat batteries to market in the wider heating market. So, Andrew, first of all, a CEO of a fast growing company. I asked you at the beginning, are you a developer, a manufacturer, a vendor? And you said all of those. So you've got a lot of balls to keep in the air, a lot of plates to keep spinning. How do you break that down? You must worry about finance, about technology, about sales, about people. Are there three legs of the stool in terms of how you break this down, or are there a lot more legs than three and how you think about it?


[00:11:29.170] - Andrew

I need to think how I frame this, because you're right, there are a lot of legs. It's probably like a table and chairs rather than just one stool. But I suppose it starts with you have to have some kind of disruptive, in my world, you have to have some kind of disruptive concept that you believe you can bring to market. I'm a technology entrepreneur, so I would always look for a disruptive concept starting from a solution, an ability to solve the problem technically. Other people come at it from market disruption, new business models and so on. I probably come at it more from a technology side. We beavered the way in a very small team for the first four or five years to get the technology kind of wrapped, to understand everything we had to do to break it down, build it back up again, and come up with something very differentiated.


[00:12:36.790] - Jon

In that stage. Andrew, how did you pay for that? Did you need to raise money or was it helped by you having exited a successful business in the past?


[00:12:47.480] - Andrew

Yeah, the latter. We obviously leveraged the grant assistance wherever we could. We had a deck, an SBRI, a Small Business Research and Innovation award in 2013, but by that point and I think we had an Innovate UK award a little bit earlier, but by that point, we'd probably spent a few hundred thousand of our own money. So that's a privileged position to be in on the back of having exited a previous business. But we took full advantage of that. Once you get to that stage, though, you have to start taking investment, and you have to do that because you need to have a lot more people. You can't just do it with a team of three or four. You have to start having a team of ten and then 20 and then 40 and then 60. And you know, that's the stage we're at. And I think by 2025 will probably be 500 people in this organisation. So you have to grow the human resource in the company significantly. And people are the bedrock of being successful. And we've got a great team.


[00:13:59.830] - Jon

When you look back, we'll look forward in a minute. But when you look back, there's the finance side, the building, the team, they're finding the partners in the market, the distributors you mentioned. What bit do you look back and you think all of it is critical, but what part do you think was the hardest or what do you look back and think - I'm so proud. This is where it was the biggest challenge and we really overcame it.


[00:14:33.950] - Andrew

I think there's lots of biggest challenges. It's more like the hurdles race.


[00:14:39.050] - Jon

It's not a fair question.


[00:14:40.910] - Andrew

The one where you run to the line and that's it. You're over it, you keep jumping hurdles. So, I mean, I suppose the first thing was building a successful heat battery that could cycle, that could deliver. And this is really important. High flow rate hot water. That's critical because if you can't do that, you can't substitute a hot water tank. That was a key requirement that we set ourselves.


[00:15:07.610] - Jon

Presumably for that requirement, it's not just a technology requirement, it's a technology for an application, correct?


[00:15:14.690] - Andrew



[00:15:15.570] - Jon

And that's a trap I've seen a lot of technology fall into is not matching the technology requirement of the technology with the application requirement. Could you hold in on that straight away, or was it clear to you what the exception was?


[00:15:28.860] - Andrew

Pretty much. I mean, at the very beginning, our competitor that we wanted to disrupt was the gas combi boiler.


[00:15:38.970] - Jon



[00:15:39.420] - Andrew

We wouldn't get there in one band, but the competitive set is people pulling gas, which is stored fossil energy, stored fossil sunlight off a distribution network. That means they can have a tiny device in their house that delivers them heat and hot water and makes their lives happy. And if you want to do that in a net zero way, we didn't call it net zero back then. But if you wanted to do it zero way, you had to work with today's energy from the wind and the sun and store it briefly. And that meant you had to have a very small storage. Then actually, you home in on what's the hardest bit of that to do? And actually the hardest bit to do is hot water, because hot water has the highest thermal power. So we did that first. Our view has always been climb Everest first and all the other peaks are easier.


[00:16:30.990] - Jon

Yeah. Okay. And then as you grew, you've got the technology right for the application. That Everest application.


[00:16:39.630] - Andrew



[00:16:40.030] - Jon

Have there been any fundamental choices after that? Like, did you think, do we want to manufacture or do we want a licence? Are we an IP company? Have you had any of those choices that could have taken you in quite different directions to build on that technology you developed?


[00:17:00.450] - Andrew

I suppose I had the benefit of hindsight to a previous business. So in the previous business, we were a software developer in the medical imaging space, very different. But we had the same choices about do we make our own product and sell it to the market or do we licence it to OEMs? And initially we said we'll licence it to OEMs and we didn't get anywhere. We were years and years talking to product managers and research and development teams who would say, I don't see the need for this or we can do it ourselves internally? And so we then went to the market with a product and disrupted the market. And then we were able to win all the OEM relationships. In this business we took that learning and we said we'll build a product, go to market. And by doing so, we will encourage all the OEMs to come and talk with us. And in fact, that's exactly the trajectory that's happened.


[00:17:52.890] - Jon



[00:17:53.440] - Andrew

Although I can't reveal every single name, we're probably in conversation with 50% of the global HVAC industry.


[00:18:01.110] - Jon

Yeah. Okay, very interesting. Okay, thanks, Andrew. Let's move on to the second part now, which is looking at how heat batteries will be used. So, Klara, can you give me some use cases that you've been digging into?


[00:18:18.070] - Klara

Yeah, exactly. So in our thermal storage research, we identified three key use cases for heat batteries. First of all, they can help overcome one of the key barriers for heat pump installations, which is the space requirement of not only the heat pump unit, but also a big hot water tank.


[00:18:36.870] - Jon

So in the example Andrew used of a gas combi boiler, you don't need a hot water tank. If you're replacing a comb boiler with a heat pump, you need a heat pump and a hot water tank. So the spaces are really important.


[00:18:46.760] - Klara

Exactly. So as much as you can reduce the space, the better. And like you said, heat batteries are a lot more energy dense. They can be more compact, but they can also reduce their energy use and the customers bills by learning use patterns and optimising the timing of hot water production to really bring benefits for the customer.


[00:19:10.230] - Jon

Okay, so with heat pumps, facilitating heat pump installations.


[00:19:14.030] - Klara

And then the second one is it can be used together with a direct electric heating element and then be the primary heating appliance in its own rights and then be a drop in replacement for a fossil hydronic heating system.


[00:19:29.590] - Jon

Okay. So if you've got an off peak electricity tariff or you're on a dynamic tariff, you can use that cheap electricity.


[00:19:36.970] - Klara



[00:19:37.950] - Jon

And then store it for when you need the heat.


[00:19:41.070] - Klara

And then the final one is that which we've also touched on briefly, is that heat batteries can contribute to self consumption from PV, it can be used as a really good alternative to electric batteries and store that excess solar energy.


[00:19:55.250] - Jon

Okay. So rather than exporting the solar energy to the grid, I can use it to do all my hot water for later that day. Andrew, how would you put those three in order? Well, maybe again, an unfair question. Can you put those in order of what you're focusing on at the moment, or are they all equally exciting, or are there variations on that that you'd like to bring out?


[00:20:21.970] - Andrew

No, I think we probably can put them in order. In terms of their importance to A, our business and B, in our view, the way in which the energy transition will unfold. Although we started with the PV application, with PV self consumption and it is an important application, it's not going to be the biggest. The biggest application out of the three you listed is going to be the enablement of heat pumps. We are in now, probably today, somewhere between 2 and 5 thousand homes where I can't give you the precise number because I don't know, it two and 5000 homes where ground source heat pump on a shared ground loop in apartment buildings or air source heat pump in individual dwellings is enabled fundamentally by having this very compact store available to make the hot water to replace. And we're talking about something, by the way, the size of a slim line dishwasher.





[00:21:34.760] - Andrew

That's a slimline dishwasher instead of a hot water tank that's pretty big, as tall as me and as wide. And I'm not small. That differentiation. Not every house needs it. I mean, some houses will be fine. There'll be a cylinder cupboard from previously, and a cylinder will go in. Happily, although often people like the safe space because they can reuse it for other purposes. But in lots of homes that was never there or it's been reused or there's been a modification to the use of space. In our view, heat pumps are terribly important right now. There's a lot of work going on to accelerate the adoption rate for net zero reasons because of the war in Ukraine and because of the desire to massively reduce the consumption of gas, we should deploy a lot of heat pumps very fast. And if you look at it probably in 50% of homes you'd like to deploy a heat pump into, the heat battery will be the enabler because the hot water tank won't fit. I think that’s by far the biggest application out of the three you've mentioned.


[00:22:52.270] - Jon

Yes. Particularly when we're looking forward. If you look at where heat pumps across Europe have really succeeded date, I think it's largely off the gas grid where the displaced oil boilers that would typically have had a hot water tank with them.


[00:23:01.270] - Klara

And an oil tank.


[00:23:02.270] - Jon

And an oil tank. Yeah. So whereas if we look going forward, if heat pumps are going to displace natural gas, then gas boilers might emit carbon. But they're amazing products. They're compact, they produce high temperature heat, high flow rates, as you said, Andrew. So, yeah, those space requirements I can see become a huge enabler.


[00:23:36.910] - Andrew

In 2013, our very first install was into a house on the gas grid. Mine.


[00:23:44.070] - Jon

What did you have in your house at the time?


[00:23:46.100] - Andrew

I had a gas boiler. It was a gas system boiler with a nice cuboid, actually, as it happens, hot water tank. So it was a Gledhill something or other. And we replaced it with a heat pump and some heat batteries because I wanted also to do space heating at the time shift. But actually, the hot water application is really central to getting heat pumps deployed. The time shifted cases will become important when the tariff structures, which really depend on the complexities of regulation of the grid, when they catch up, they haven't really caught up. And they don't reward individual consumers for making what I would term the right choices. They tend to reward flat consumption profiles, not the reality of something that aligns anyway, leaving that to one side, because I think that's kind of under important. Almost everything we've done since has been into homes that were on the with heat pumps, has been into homes that were on the gas grid that are on the gas grid. We're into apartment blocks that had combi boilers in and now have Kenza heat pumps, Sunamp heat batteries and a shared ground loop that's in over 2000 apartments now in the UK, in Sunderland, in Leeds, coming soon, in Newcastle, in London, in possibly actually maybe Edinburgh soon, depending on how something goes.


[00:25:24.360] - Andrew

Maybe I shouldn’t have said that - we may have to edit that out!


[00:25:26.340] - Jon

But, you know, but that's your Everest of an application, isn't it?


[00:25:31.340] - Andrew

That is a fantastic application. It's really hard to take high rise blocks that have gas combi boilers and turn them into heat pump blocks. And we've done that. But we've also done it for individual homes that are on the gas grid in huge numbers.


[00:25:45.730] - Jon



[00:25:46.080] - Andrew

I'm proud of that.


[00:25:47.010] - Andrew

But you didn't mention application zero, Klara. For us, actually, so far the biggest seller is electric hot water. Just put simply main electricity in cold water comes into the heat battery, hot water comes out, it replaces a direct cylinder, and it does it in a quarter of the space. And it turns out that people love it because of the space.


[00:26:16.190] - Jon

Because of the space.Yeah.


[00:26:16.600] - Andrew

And they almost certainly already had a hot water tank.


[00:26:22.110] - Jon

Well, my guess is we've got some listeners in Germany that have houses with basements that are fully devoted to a heating system, scratching their heads, thinking, what's all this talk about space? We've got a whole cellar where we have our heating system. I know there are houses in Germany equally that have comb boilers and struggle with space. So part of what I think the challenge and fascination with decarbonising heat is a huge mixture of houses and heating systems. Absolutely.


[00:26:56.110] - Andrew

Can I just say this does make it more difficult for us when we talk with German OEMs, because the people that run German OEMs are, by and large, averagely wealthy or above.


[00:27:00.110] - Jon

They have a cellar and plenty of space!


[00:27:05.110] - Andrew

The definitely have the house with the big cellar, right?

[00:27:11.520] - Klara



[00:27:11.810] - Andrew

They do not see the problem in their own lives. But if you talk to somebody from Korea or the Netherlands or Belgium, UK or large swaths of the US, they understand.


[00:27:25.210] - Jon

Yeah. I want to move quickly on to that third topic I mentioned,  before we get the Talking New Energy Crystal Ball out. So the third topic is routes to market here. Klara, what's the challenge with routes to market for new heating technology?


[00:27:42.850] - Klara

Well, the route to market for the heat sector is really dominated by either by wholesalers or directly to installers. And that means that these two channels have a really important role to play when it comes to introducing new technologies to the customer and especially installers, since they have the customer relationship. And that was actually confirmed by our latest customer research, where over 70% of respondents said that they would be very or quite likely to turn to their installers for recommendations rather than any other source.


[00:28:15.010] - Jon

So consumer awareness is low. It's installers who say - or this is what you want.


[00:28:20.340] - Klara

Yeah. I think especially for new technologies, customers might be familiar with what they have, but they might not be familiar with any kind of alternatives.


[00:28:28.070] - Jon



[00:28:28.960] - Klara

However, since many installers might also be conservative when it comes to these new technologies and they might not be great at selling a new technology or idea to the customer, it will definitely be challenging in the future. But we also see other players and influencers emerging. For example, energy companies and energy service providers who also have an existing customer base and also have an interest in the flexibility values that these thermal storage units can provide. That could be an alternative route to market in the future, a bigger route market.


[00:29:02.520] - Jon

Okay. And they might be once they've understood the technology, a bit less risk averse, perhaps.


[00:29:07.650] - Klara

Yeah. And they can see the benefits for them, maybe more than the installer could as well.


[00:29:13.420] - Jon

Yeah. Okay. So the customer gets a space benefit, but the energy supplier can maybe get some of that flexibility benefit.


[00:29:18.980] - Klara



[00:29:20.650] - Jon

Okay. So not an easy market, Andrew, for new technology. Briefly, how are you going about that? Are you trying to drop it into existing channels? Are you developing new channels?


[00:29:33.730] - Andrew

Well, first of all, can I say I completely agree with Klara. There is no doubt that you've hit the nail on the head with everything you've said there. We did an experiment at the beginning with being business to consumer by trying to basically because actually we needed to learn we needed to learn what customers wanted to learn directly from them, to engage with them. We literally sold directly to individuals in their homes. And it's a brave company that would choose that as their long term business model. If they're also a manufacturer, because it's quite a difficult path. And certainly we went from there to being 100% business to business. We work with some great companies that go direct to customers in one way or another. They're into big projects for housing associations. They are the customer is the housing association, but the tenants are the ultimate beneficiary. We are also working with other people who go direct to homes to sell to individuals. We are working with utilities and energy service providers. And I think that area will expand dramatically. And there will be novel business models in there. But a lot of what we do today is very traditional into distributors because we've specifically configured our products.


[00:31:06.180] - Andrew

Our Thermino product range is configured to work like a hot water cylinder at the point of installation. Anybody that can install a hot water cylinder can install a Thermino product. And I think that's really important because it means we're a substitution play into those distribution channels. We're not going to be cheaper. Right. We're a premium product, although we're not much of a premium in terms of price. We're a huge premium in terms of installability.


[00:31:37.950] - Jon

So, a forward thinking installer. Andrew might look at your product on the shelves of a distributor, think, oh, I can do that. And that means it will make my conversation with Mr. And Mrs. Jones a bit easier because I know they're struggling for space. So actually, I'll take this product along for them to look at.


[00:31:58.700] - Andrew

Yes, that's happening.


[00:32:00.270] - Jon

Yeah. Okay. So you're looking at multiple channels to market, and part of that will involve brand awareness, but part of it might not, I guess, if it's Joe Bloggs Heat Pumps, if they branded it Joe Bloggs Heat Pumps, plus Joe Bloggs special storage tank, for example. Would you mind?


[00:32:19.990] - Andrew

Not only do we not mind, we do it today.


[00:32:24.520] - Jon



[00:32:26.970] - Andrew

The very public one is Flamco in the Netherlands and across Europe sell a FlexTherm Eco product, which is basically a Sunamp product under the hood. And that's well known. But there are others maybe a little bit less visible, and there will be lots more. So we are completely open to white label, full OEM integration of our core technology deep inside the product, even for some people, selling the Plentigrade phase change material and licencing the core technological pieces. In a sense, we're completely agnostic.


[00:33:17.190] - Jon

Whatever the best way it is to get your technology or product to market.


[00:33:22.080] - Andrew

Absolutely. Because we don't think there's time to hang around. I don't mean that from a business perspective. I mean that from a net zero perspective. There isn't time to waste here.


[00:33:36.190] - Jon

Okay. Fascinating. Let's move on out to the Talking New Energy crystal ball, and I'm going to set the dial for both of you this week to eight years time. And if you can answer it briefly, just in the interest of time, Andrew, can you describe in a nutshell, Sunamp in the year 2030. Can you describe very briefly how widespread you think the use of advanced thermal storage will be in 2030? Andrew, do you want to go first and then Klara.


[00:34:10.950] - Andrew

Okay. That's setting me up for a fall, isn't it? I think the market for hot water storage devices in 2030, I think was the reference date is going to be something in the order of 50 million units a year. And I think we'll be selling somewhere in the order of one to 5 million of those using the technology platform we're talking about. Many of them, maybe most of them, will not be under the Sunamp brand. Sunamp itself is probably going to have 1000 plus employees at that point. We'll be doing a billion plus of revenue per year. We'll be active across at least 20 countries. We're already active across nearly that many today. And we're likely to have three or four factories, at least one in Scotland, one probably in China, and one probably in the US, and some smaller factories in other places, some under licence.


[00:35:10.510] - Jon

Great. Well, I hope you're not setting yourself up for a fall Andrew. I hope that you reach that or exceed that. But that's a great trajectory you are on and wishing you the best of luck and success on your way to that 2030 vision. Klara, how about you? Advanced thermal storage in 2030?


[00:35:34.750] - Klara

Yeah, well, I'm hoping and assuming that low carbon heating is a lot more widespread than it is now and nearly all of those appliances will require thermal storage, I think I can say with quite a lot of confidence that some kind of thermal storage will be nearly every home. And since if heat batteries, the cost can be brought slightly closer to those of traditional hot water cylinders, and then the benefits they bring around flexibility, then I think it's very likely that a decent proportion of those low carbon heating systems will have heat batteries in eight years.


[00:36:16.660] - Jon

Which fits in with the sort of Andrew’s 50 million, and 1 to 5 million being Sunamp batteries per year, I should say.


[00:36:25.370] - Andrew



[00:36:28.610] - Jon

Well, it sounds like heat batteries are going to be a part of our future heating transition and very possibly very likely a big part of our future heat transition. If we’re to decarbonise heat, we will need thermal storage, and space and flexibility will be key issues in achieving that. Andrew, thanks very much for your time and sharing your thoughts and experiences. I really appreciate that.


[00:36:58.370] - Andrew



[00:37:00.830] - Jon

And Klara, thanks for sharing your expertise today.


[00:37:03.390] - Klara

Thanks for having me.


[00:37:05.150] - Andrew

Klara, thank you for your expertise. I really learned something as well.


[00:37:10.840] - Klara

Thank you. That's very sweet.


[00:37:12.770] - Jon

And as always, thanks to everyone for listening. I hope you've learned a bit about heat batteries and advanced thermal storage today. Maybe going back to your own home and looking at your heating system and having a look at space in your home. Who knows? And look forward to welcoming you back to the episode next week.


[00:37:30.610] - Jon

Thanks very much and goodbye.


Add yourself to our mailing list

Add yourself to our mailing list