Plugged In: the energy news podcast
Coming from the heart of the Montel newsroom, Editor-in-Chief, Snjolfur Richard Sverrisson and his team of journalists explore the news headlines in the energy sector, bringing you in depth analysis of the industry’s leading stories each week.
Richard speaks to experts, analysts, regulators, and senior business leaders to the examine not just the what, but the why behind the decisions directing the markets and shaping the global transition to a green economy.
New episodes are available every Friday.
Plugged In: the energy news podcast
Drink whisky, help save the planet - fuelling the energy transition
How could our Christmas leftovers, such as rejected potatoes and 'pottail' from whisky distilleries, fuel the energy transition?
In our final episode for 2025, Richard sits down with a company in Scotland to discuss how they produce bio-based green chemicals from food and drink byproducts, and how these greener alternatives are already helping pharmaceutical and cosmetic industries wean off fossil fuel chemicals.
Host: Richard Sverrisson - Editor-in-Chief, Montel News
Contributor: Gabriel Power - UK Reporter, Montel News
Guest: Mark Simmers - CEO, Celtic Renewables
Editor: Oscar Birk
Producer: Sarah Knowles
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Hello listeners, and welcome to Plugged In - the Energy News podcast from Montel, where we bring you the latest news, issues and changes happening in the energy sector. Well, the festive season is nearly upon us. In the coming days, many of us will be enjoying a Christmas tipple or two and indulging in some traditional Jul tied food with all the trimmings. But could our festive leftovers fuel more than just our stomachs. Last week we had the EU Energy Commissioner on the podcast discussing among other things the importance of the move away from fossil fuels. This week we delve a little deeper. We speak to a small company in Scotland that is working with whiskey distilleries and food producers on the ground to make this mission a reality. The energy transition requires not only a switch away from gas and power generation. The bigger picture, but also the greening of many processes that are hard to abate on a much smaller scale. These small companies will play a vital part in the greening of the economy. I'll be speaking to our guest all about this very shortly, but first, I'm pleased to be joined by our UK reporter, Gabriel Power. Welcome back to the podcast, Gabe.
Gabriel Power - UK Reporter, Montel News:Thank you for having me back. So nice to see you.
Richard Sverrisson - Editor-in-Chief, Montel News:We are talking about the small companies involved that are also very important in the energy transition, Gabe, but how much are big companies like pharmaceuticals, cosmetics, et cetera, reliant on fossil fuel based chemicals for their products?
Gabriel Power - UK Reporter, Montel News:Well, very reliant. According to UK energy bodies, almost all chemicals used today, including those used in pharmaceuticals. Cosmetics are still made from fossil oil and gas. And so yeah, we're not talking about energy. We're talking about the literal basic ingredients that go into things like medicine, personal care, and everyday materials. Even companies that have made progress on decarbonizing, their electricity supply will still mostly depend on fossil derived feed stocks in their supply chains. And that's why according to the BBIA, which is the bio-based and Biodegradable Industries Association, the chemical sector alone accounts for around 10% of global greenhouse emissions. So it's a huge and often overlooked part of the climate change problem.
Richard Sverrisson - Editor-in-Chief, Montel News:And if we're gonna make the energy transition a success, we have to get these companies on board, or they have to start greening their processes, right? We're going to be speaking to a UK based companies shortly that, that produces bio-based green chemicals as an alternative to actually exactly what you were mentioning, the oil and gas feed stocks. Are we seeing a growth in these types of businesses in the UK?
Gabriel Power - UK Reporter, Montel News:Yes. It's becoming a very big sector in its own right in the uk UK government data from DEFRA, which is the department for Environment, food and Rural Affairs shows that large volumes of agricultural and food related byproducts are already being used across the bio economy. In 2023 alone, which is the most recent data that they published around 130,000 hectares of UK farmland were linked to bioenergy production, while millions of tons of food waste, crop residues, agricultural byproducts, et cetera, were used in processes like anaerobic digestion. As a result, industry and government strategy documents show a clear shift from using these materials. Just the energy towards higher value uses like low carbon chemicals, as you said, and other materials. And the UK chemical sector has set out a target that by 2050 it wants to have doubled in size while sourcing 30% of its carbon feed stock from fire mass. Again, that's according to the BBIA.
Richard Sverrisson - Editor-in-Chief, Montel News:And these 23 figures. So they might be quite, look quite different than 2025. Go. But that's, that'll be pure speculation on our part. Thanks very much Gabriel. So how can rejected potatoes and whiskey byproducts help the energy transition? It's my pleasure to welcome to the Plugged In podcast Mark Simers, who's the CEO of Celtic Renewables. A warm welcome to you, mark. You're gonna talk to us about, to the byproducts of whiskey, for example, and how that can be used through to to push through the green transition.
Mark Simmers - CEO, Celtic Renewables:Delighted to be here, Richard and looking forward to our conversation.
Richard Sverrisson - Editor-in-Chief, Montel News:So Mark, what are bio-based green chemicals and how are they created?
Mark Simmers - CEO, Celtic Renewables:Yeah, so we use a process called ABE Fermentation, which stands for acetone, butanol, ethanol, and these three based chemicals. Particularly aceton and butanol almost exclusively come from fossil fuel. And so what we're doing is making the same chemical but through a sustainable biological pathway by using the byproducts and leftovers of other industries, particularly food and drink. And so we're creating really the same molecule that's used all over the world to make lots and lots of everyday items, but doing it through a sustainable biological pathway.
Richard Sverrisson - Editor-in-Chief, Montel News:What kind of fossil fuels are used in that process then?
Mark Simmers - CEO, Celtic Renewables:Yeah, so I mean, ultimately it'll come out of crude oil or natural gas. And effectively through the refining and cracking process of that, you know, you end up with these two chemicals and it's used in pharmaceuticals, cosmetics, personal care products, food, flavorings et cetera. There's so many sectors that use these chemicals on an everyday basis, the customers that we're deep engagement with now are all looking for an a, a biological, a bio-based chemical as an alternative.
Richard Sverrisson - Editor-in-Chief, Montel News:And you mentioned byproducts and waste products as well, Mark. What ones in particular?
Mark Simmers - CEO, Celtic Renewables:So we're based here in Scotland, and so to begin with we're using the Leftovers, a whiskey production. When you make, you know that famous Scottish product of clearly other countries make whiskey as well, but we're very proud of that here in Scotland. Or less than 10% of what comes outta a distillery is actually the spirit that becomes, that amber liquid and the rest are byproducts and those present the whiskey industry with a disposal challenge and potentially a commercial cost of disposal. And we provide a process that would utilize those, those production leftovers and put them to better use to create a value add. And what works for whiskey in Scotland would work for drinks industries for potentially food to leftovers. We're using reject potatoes in our plants, so effectively the. The byproducts of agriculture and a whole range of other feedstocks where we're creating a really good circular reuse model for what is currently, a kind of byproduct or waste from another industry.
Richard Sverrisson - Editor-in-Chief, Montel News:No, it's very interesting. So also intrigued by the whiskey side of things here, the mark. As this, the grain we're talking about also some of the liquid. Liquid byproducts as well.
Mark Simmers - CEO, Celtic Renewables:So yeah, predominantly are we using the liquid byproduct. So that's what's left over after the first distillation of spirit unit distillery. It's called pottail and it costs the industry money to get rid of this byproduct, but it's got good nutrients in it, you know, it's actually a liquid that can be utilized particularly for biological processes like ourselves. You know, we. Have that delivered from two or three local distilleries to our first plant here in Central Scotland. And then we add, some sources of carbohydrate, the reject potatoes I talked about, to make a recipe that then becomes the basis from which we can make these chemicals.
Richard Sverrisson - Editor-in-Chief, Montel News:That's fascinating. Are these big distilleries you deal with or are they smaller scale, or could they be based anywhere in Scotland basically?
Mark Simmers - CEO, Celtic Renewables:Yeah based anywhere. Yeah. We're working with three out of what, 130 distilleries. One is owned by Diageo, one of the biggest strengths brands in the world. One's a distillery that's relatively local to us in Falkirk, in Sterling. And ultimately they love the sort of provenance story of what we're doing. It's very fitting with their own net zero and decarbonization ambitions. And it's just a great circular story in terms of using primary industries byproduct and doing something you know, really valuable and that's good for the planet.
Richard Sverrisson - Editor-in-Chief, Montel News:And I'm sure once you are looking for new distilleries to source from 'em. You can go around and have a little tip away there. I presume Mark.
Mark Simmers - CEO, Celtic Renewables:Yeah. It's a great industry to be aligned with, obviously some iconic brands and yes a weed glass of whiskey is always very nice to to try now and again.
Richard Sverrisson - Editor-in-Chief, Montel News:Absolutely, and especially in this festive period. But Mark, if we, you say this could also apply to, for example, producers of vodka or tequila or gin. There's a preponderance of gin distill distilleries all over the UK. There's had quite a rebirth, hasn't it? But the same principles could apply there then, could they?
Mark Simmers - CEO, Celtic Renewables:Yeah, absolutely. This is a global opportunity. We're part of, for instance, the Clean Ganges program in India. There are 24 distilleries in the Ganges base, and we could help to prevent the disposal of, whiskey effluent there. We're in discussions with a number of distilleries and that make rum in the Caribbean. So this has got, application all around the world.
Richard Sverrisson - Editor-in-Chief, Montel News:But these sort of acetone, butanol, ethanol components, do they have to be used in combination with carbohydrates and other waste products then?
Mark Simmers - CEO, Celtic Renewables:No, not at all. We're working now with customers where they would entirely move. Some of their production processes or the products that they're making onto purely bio-based chemicals and move completely away from fossil based equivalents.
Richard Sverrisson - Editor-in-Chief, Montel News:So how are these bio-based green chemicals used then?
Mark Simmers - CEO, Celtic Renewables:In the same way for instance, we're working with a chemical intermediary company in Germany and they're making what's called emollient for skin creams. To effectively to make skin creams go on really smoothly. And at the moment they're using fossil based butanol to make those emollient. And they're really excited about being able to make an emollient from effectively a bio-based chemical rather than a fossil based chemical. We're working with a number of the pharmaceutical giants who use both acetone and butanol as effectively reagents or catalysts within the medicine production processes, and again, they're trying to move away from using fossil based chemicals to using bio-based chemicals. And those are just two out of really hundreds of examples of where these bio-based chemicals can be used.
Richard Sverrisson - Editor-in-Chief, Montel News:And is there any difference between those that are used, bio-based and those that are, fossil fuel based in terms of the quality of the end product?
Mark Simmers - CEO, Celtic Renewables:One of the things that we realized in terms of building up, this opportunity is that our chemical had to be at least of the same level of quality as the fossil based equivalent. Ultimately that had to happen to ensure that these major customers could effectively swap onto a buy based alternative without having to change their processes or recertify. I processes to be able to use them. So ostensibly it's just a drop in replacement.
Richard Sverrisson - Editor-in-Chief, Montel News:And in terms of costs?
Mark Simmers - CEO, Celtic Renewables:Yeah, we're, we're not cost competitive at the moment because we're only producing at a relatively small commercial scale. This process was born out of a university research project. We've built our first of a kind commercial plant in Scotland. The net stage is to build a much bigger industrial scale plant, which will start construction of next year in 2026. Yeah when we get to full scale we should be able to be cost competitive with, the current pricing of fossil based chemicals.
Richard Sverrisson - Editor-in-Chief, Montel News:And where are you building this plant?
Mark Simmers - CEO, Celtic Renewables:We're actually gonna build it in Grange mouth and where our first plant is, there's been, recent closure of the Petra refinery here in Grange mouth, which is obviously not great for the Scottish economy. So Scottish and UK governments are really focused on redeveloping grange, both as a low carbon manufacturing complex. So we are one of the first processes that will spearhead that transition from, effectively petrochem to biochem and so. There's good support for that, but also it's a great opportunity to repurpose land, repurpose utilities, and we have access to a really good sort of pool of manufacturing and operating talent from a chemicals production perspective.
Richard Sverrisson - Editor-in-Chief, Montel News:So providing jobs in the area as well? No less. But in terms of scaling it up, is that quite feasible then?
Mark Simmers - CEO, Celtic Renewables:Yeah, it's a batch fermentation process if any of your listers and viewers have been to a distillery or a brewery, they're just great big fermentation tanks and we've got five large fermentation tanks in our first plant. We'll have 16 slightly larger fermentation tanks in our next plant, and with the ability to scale beyond that the scalability of this process is pretty straightforward and doesn't involve any degree of further technical challenge.
Richard Sverrisson - Editor-in-Chief, Montel News:Could there also beer production or wine production, is that also the same so that you could use some of the byproducts from there as well?
Mark Simmers - CEO, Celtic Renewables:Absolutely. A lot of these brewing and distilling processes, they're both, they're solid and liquid leftovers are applicable for this process. So yeah we're in discussions with large brewery companies, certainly looking at the wine industry, both across Europe and the rest of the world as potential sources of this feedstock. Where we build these plants is largely, will largely be feedstock led. We want to build them close to the source of feedstock and then ship the products on from there. So that it then creates really good sort of circular and synergistic link with the upfront originators of those feedstocks. That's the kinda model that we're focusing on.
Richard Sverrisson - Editor-in-Chief, Montel News:Oh, fascinating. I'm sure a lot of beer, wine and whiskey drinkers will be very happy that they're contributing to the green transition there, Mark.
Mark Simmers - CEO, Celtic Renewables:Yeah, Yeah. We sometimes foresee say, drink more alcohol to save the planet,
Richard Sverrisson - Editor-in-Chief, Montel News:but I could subscribe to that.
Mark Simmers - CEO, Celtic Renewables:That's perhaps, yeah. Yeah. I was gonna say that's probably not terribly moral in terms of a suggestion, but yeah, it's purely meant ingest, but ultimately, being able to reuse material that currently is a disposal problem, is the way forward.
Richard Sverrisson - Editor-in-Chief, Montel News:Absolutely. And so in terms of the carbon emissions is it zero emissions here or is it, how does it compare to the fossil fuel production of these chemicals?
Mark Simmers - CEO, Celtic Renewables:So at the moment we're about 60% Richard. Saving on a like for like basis, we're pretty encouraged with that. One of the key approaches we've got with our next plant is to begin to integrate other biological processes. So not only will we produce aceton, butanol, ethanol, but we'll integrate biogas production. We make green hydrogen and food grade CO2, and ultimately we will then clearing up the water at the back end and recycle that. So we, we expect that by the time we build our explan, we'll be, virtually carbon neutral if not a carbon, sump in terms of what we do. So we will get to, a hundred percent carbon saving, which is where we want to get to.
Richard Sverrisson - Editor-in-Chief, Montel News:Absolutely. In terms of the financing, are you relying on any sort of public funding or subsidies?
Mark Simmers - CEO, Celtic Renewables:We work with the Scottish government and the UK government in terms of sort of capital investment and they've been very supportive of us. But, certainly around chemicals, unlike energy there's no subsidy that's applicable to what we do. We hope that in the not too distant future, governments will start to mandate targets around biochemicals and biomaterials to really encourage. Both industry and consumers to move away from fossil based materials. And that's where we're aiming to get to.
Richard Sverrisson - Editor-in-Chief, Montel News:Absolutely. And do you, is there any kind of guarantee of origin kind of certification for some of the, these processes as well? Mark?
Mark Simmers - CEO, Celtic Renewables:We have a hundred percent biogenic carbon certification that we utilize for all our products just to prove that, none of what we produce is, has come from fossil fuel. And so that, that's the main certification we've got from that perspective that is required by our customers.
Richard Sverrisson - Editor-in-Chief, Montel News:And, you guys a very good example of how you can move from fossil fuel to low carbon chemicals. What are the challenges faced by industries such as yours?
Mark Simmers - CEO, Celtic Renewables:I think scaling is just really hard. We started out as a, literally a test tube in a lab and trying to navigate through, we've been going now for 13, 14 years since that, that early stage. It takes a lot of time, energy, investment and real belief in what you're trying to achieve. We're a very purpose led business, in what we're trying to do, but there's lots and lots of examples of similar businesses to ours that haven't made it. So it's a pretty hard journey to get from, where we came from in a lab and a university up to, the scale we're operating at now. We're frankly pretty proud of what we've managed to achieve, but it's not an easy journey and particularly the investment markets in it, not just the UK but actually really much across the world in terms of growth capital, are very risk averse at the moment. The challenge of raising capital for something that is a varying capital intensive endeavor is not easy.
Richard Sverrisson - Editor-in-Chief, Montel News:Absolutely. I can see that the marketing conditions at the moment are probably not the best they could have been, but, but Mark, in terms of the feedback you get from customers and who are using these products, is that, can you see a growth in demand out there and in which industrial sectors in particular.
Mark Simmers - CEO, Celtic Renewables:More and more demand coming. And I think we are really a pioneer in terms of what we do in terms of producing bio-acetone and bi-butanol. And you can see, big pharma companies. Companies and cosmetics and personal care, kinda saying. Oh, we've been waiting for this for such a long time. We really wanted to be able to source large quantities of bio-based chemicals that would be applicable for our processes. And they're really thankful that this, this is now really coming and that. Our ambitions for scale marry up with the scale of their demand going forward. We're not mandated, there's no incentives. There's no requirement for these customers to take a bio-based alternative. This is very much a voluntary choice from their perspective, but the fact that choice is there and we're able to meet that desire from their side to get hold of this bio based alternative is really exciting. And I think, we'll only grow.
Richard Sverrisson - Editor-in-Chief, Montel News:Yeah, absolutely. And it, it comes at a time when there is in some areas a bit of a backlash against the green transition, seeing it in the company reports and also ESG reporting, et cetera. A question as well about the sort of a circular supply chain. How challenging is it to build that on an industrial scale Mark?
Mark Simmers - CEO, Celtic Renewables:Yeah, ultimately as a new technology, you are a disruptor. So you're trying to persuade, large whiskey companies in our position and others to go a different route and ultimately back, what is quite new. We've got to make sure that not only are we presenting a really good environmental proposition, but actually improving their commercial proposition and trying to create that sort of win-win scenario so they can really see the environmental and social benefit of the circular solution, but also benefit commercially too, ultimately. As you've just pointed out, renewables, renewable energy, renewable materials, biomaterials, fundamentally have got to be profitable endeavors and have gotta make sense. And they can't penalize customers or whether their business customers or the consumers as a whole. That you've gotta operate a business like, like ours. And in terms of developing, these new approaches, from that perspective.
Richard Sverrisson - Editor-in-Chief, Montel News:So this is a very good example whether the commercial aspects and the environmental ones go almost hand in hand here.
Mark Simmers - CEO, Celtic Renewables:Yeah, ultimately this is about both planet people and profit. And all those three have gotta be aligned. And I know that's a bit of a cliche, but actually it's a reality of running a business that like the one we are.
Richard Sverrisson - Editor-in-Chief, Montel News:You'll obviously have a bit of work to do traveling around Scotland and visiting all this distilleries. Some may envy you that task Mark. But a final question. How do you see....
Mark Simmers - CEO, Celtic Renewables:i'm really excited about it. I attended an event with the Bio-Based Industries Association at the House of Commons at the start of December 2025, which brought together, a whole range of businesses operating in a similar way to Celtic renewables. And I think our sector now really has good political backing and understanding in terms of what we're trying to achieve. And I think there's a real momentum building for those bio-based industries. Yeah I think it's moving forward in a very positive way. And there's more and more companies like us that are starting to succeed. That's a critical element in terms of both attracting investment but also, really getting public policy and government on board in terms of backing what we're trying to achieve.
Richard Sverrisson - Editor-in-Chief, Montel News:Brilliant. Mark. I think good luck with that and I think for all your listeners out there when you're next having a glass of whiskeys, think about you, you're possibly saving the planet.
Mark Simmers - CEO, Celtic Renewables:Yeah.
Richard Sverrisson - Editor-in-Chief, Montel News:So thank you very much for being a guest on the Plugged In podcast, Mark.
Mark Simmers - CEO, Celtic Renewables:Thank you Richard. It's been a pleasure.
Richard Sverrisson - Editor-in-Chief, Montel News:And new listeners, thanks for listening to this episode of Plugged In. If you enjoyed this discussion, please like rate and follow to make sure you get the latest podcast episodes as soon as we release them every Friday. We'd also love to read your reviews of the podcast. It helps us to keep up to date with what you, our listeners think of our podcast and what content you want to receive more of. Finally, you can head to montelnews.com for more news and analysis from our team of journalists across Europe and beyond. See you next time.
