Ep 5: Digging Deep into Geothermal with Hazel Starmer-Jones
Geothermal Engineering is on the cusp of operating the UK’s first deep geothermal power plant in Cornwall.
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Geothermal energy has many applications, but some of the most novel and interesting are occurring in Cornwall as we discover in this edition of the Netting Zeros podcast!
Despite being successfully deployed in the 1900s, geothermal energy for both heat and power has only recently become economically viable in the UK, making it a potentially impactful means of helping the country meet its net zero targets as costs reduce further.
We’ve talked about the potential for wider deployment of ground-source heat pumps (or shallow geothermal systems) for homes and businesses on the podcast previously, but at Geothermal Engineering Ltd (GEL)’s United Downs Deep Geothermal Power (UDDGP) project, we met a team on the cusp of launching the UK’s first deep geothermal power plant.
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At the time we spoke, our guest and guide on all things deep geothermal, Hazel Starmer-Jones, was GEL’s Development Manager, a role encompassing business development, new site exploration and project management – including keeping the community informed and onside during deep well drilling. She has since moved on to become Senior Development Manager at Penso Power Ltd.
A geologist by training, Starmer-Jones’ passion for her subject radiates like heat through the radioactive rocks that lie beneath the GEL offices and (soon), the UK’s first geothermal power plant.
Having graduated with a MEarthSc degree from the University of Oxford and spending a three-year stint as a geologist, Starmer-Jones took on various civil service roles before returning to geothermal development.
Aside from knowing her subject inside out, she is an articulate and inspirational example for anyone who wants to expand on their core domain knowledge and develop into a sustainability project leader.
“We'll be generating about 3 MW of electricity, which would be enough to power maybe 5,000 homes, so we're scaling up [and] looking at getting four more projects up and running over the next few years, and they'll each be 5 MW.”
Drilling beneath the batholith
Deep geothermal heat and power is an intriguing proposition that has yielded recent exciting developments in the UK. The British Geological Survey, for example, has been mapping the country to unearth sites with the most potential to recover geothermal energy sources.
The BGS team has been looking at carboniferous limestone at depths of about 4km and estimates there is recoverable thermal power of 106-222 GW. This would be 10 to 20 times the current offshore wind capacity in the UK, so it's important to look at these numbers in context. Just because the heat is in the subsurface, doesn’t mean it's economically viable. In any case, United Downs is playing on entirely different terrain…
We discover that a stretch of land running from Dartmoor to the Isles of Scilly sits atop a radiogenic granite batholith chock full of uranium, thorium and potassium isotopes, which release heat as they decay. GEL has tapped into this resource, discovering one of the richest highest concentrations of lithium in Europe in the process, and is now working with partners to extract the lithium at an adjoining processing plant (more on which next episode when we speak with GEL CEO Ryan Law!)
“At concentrations of more than 250 mg/L. GEL’s target to produce 100 tonnes per annum of Lithium Carbon Equivalent (LCE) by late 2024 will be ramped up to at least 1,000 tonnes per annum by 2026.” Source: Think GeoEnergy
The now defunct Cornwall and Isles of Scilly Growth Programme website has an excellent primer on what the UDDGP is doing and how the European Regional Development Fund (ERDF) helped to fund it, too.
GEL has drilled down five kilometres into the unknown beneath the imaging-resistant batholith to discover and tap water resources heated to about 188 degrees Celsius.
Construction of the power and lithium extraction plant is now well underway, with production at both slated to begin by the end of the year. If successful in providing heat and power to the targeted 4,000 local homes and businesses, United Downs will provide the hard commercial evidence required to accelerate similar projects in other areas of the country.
One report has concluded that by 2050, the UK could have 360 geothermal plants producing 15,000 GWh annually. As we hear in the podcast, the sector also requires many of the same engineering and maintenance expertise incumbent in the UK’s waning domestic oil and gas sector.
Community catch
GEL is also developing the first deep geothermal district heating network in the country, again in Cornwall at The Langarth Deep Geothermal Heat Network. The government in 2023 awarded the project a £22m grant as part of the Green Heat Network Fund.
The fund deploys almost £300m “to create the market conditions to accelerate deployment of reliable, decarbonised heating and cooling networks through to 2050.” Applications for Round 8 close shortly and Round 9 will open for proposals shortly thereafter.
Read the transcript:
Nate: [00:00:00] All right. Hi, everyone. I'm Nature Nate here in United Downs at the site of the first geothermal plant, or first geothermal well, in the UK. And I'm here with Hazel Starmer Jones, business development manager, geologist. And she's going to tell us a bit about what's going on under the ground in Cornwall.
But before we do that, Hazel, can you introduce yourself? How did you start working with GEL?
How did you
kind of become a
Hazel: Yeah, of course. Nice to be here, Nate. So I, as you said, I'm a geologist by background and I joined geothermal engineering limited back in the back end of 2020 as their project geologist. And my role to start with was technical reporting. So we were during testing of the wells at that time.
So there was a lot of data coming out of the project that needed to be analyzed. So that was really the focus of my role for the first few months. But then actually as. geothermal sort of interest in geothermal has increased over the last few years. My role has really transformed into future [00:01:00] sites. So gaining planning permission for new sites, making new contacts, getting in touch with landowners that could be interested in new projects.
It's really, really evolved. So I have to say these days, a lot less geology, a lot more project management.
Nate: Well, so it sounds like there's a lot of geothermal potential in the region then.
It's not just this one site. Could you Kind of paint me a picture about the geothermal potential here in Cornwall, and maybe just sort of a simplified explanation of what geothermal energy is, even.
Hazel: Yeah, of course. So really simply, geothermal is using the heat, the natural heat that's underground to generate power, electricity, or even just for heating and cooling as well at the surface. So the Earth has hotspots all over it for many different geological reasons. And here in Cornwall we have what's called a granite batholith, and that's a huge granite body.
Nate: A granite batholith. Yes. That sounds cool.
Hazel: It does, and it's huge. So it stretches all the way from beyond the Isles of Scilly, out in the west, all the way [00:02:00] through to Dartmoor National Park. So you've got the whole of Cornwall and a big chunk of Devon as well. And this granite is what we call radiogenic.
So it has uranium and thorium and potassium isotopes in it. And those are radioactive isotopes that are decaying all the time. And that decay process releases heat.
Nate: So is that a bit like a nuclear reactor under the
Hazel: Yeah, yeah, a little bit, exactly.
I got
Nate: I got that right. So then this, this nuclear reactor under the ground is just naturally heating the water, and then with geothermal we want to drill down and try and pull that water up to the surface, use it to spin a turbine, and then send that electricity, heat, power somewhere else.
And why is this happening now? Because there's geothermal in many parts of the world. Iceland, Philippines kind of small projects starting out. It didn't seem to me like the UK would be a geothermal hotspot. It's not, you know, in the ring of fire, what we might traditionally think of. What what was the barrier to developing geothermal?
[00:03:00] Why now?
Hazel: Yeah. Well, you're absolutely right. I mean, the first geothermal electricity was actually generated in the early 1900s in Italy.
So it's not a new phenomenon. It's not new technology even. It's something that, you know, a developing countries are using all over the world already. But here in the UK, it's a slightly different resource. It's not a volcanic fed system. So you're not getting temperatures that are sort of 300 degrees Celsius or, or around there.
And it's much, much deeper. So you might go out to Indonesia and only need to drill down maybe one or two kilometers to get that sort of temperature and natural flow of the water. Here in Cornwall, that's not the case. We've drilled down to five kilometers. And we do get about 188 degrees Celsius, which is really, really hot, of course.
But the hotter the resource, the more electricity you can generate, and therefore the more economic a project. So it's really, it's been an economic barrier to geothermal, really, here in the UK. And it's been quite a, quite a long journey for GEL to, to start up the UK's first geothermal power plant because of that.
Nate: So, maybe to help listeners [00:04:00] understand, how big a deal is it to drill one kilometre down versus five kilometres? I think we know, you know, most of us have maybe tried to dig a giant hole and at some point the ground gets really tough.
What, what are the barriers there? What, what's the cost increase coming from?
Hazel: Yeah so if you, if you're able to do a big exploration program at the start of your your project, you probably have quite a good understanding of what the geology is like down a few kilometers. If you're in a geological environment which you can use things like Like seismic lines, which is a classic oil and gas technique for exploring an area, you can image really quite deep underground.
However, here in Cornwall, we have essentially just granite from the surface all the way down, which doesn't lend itself very well to imaging using geophysical methods. So, firstly, you're going down a little bit blind. Once you're past a few hundred metres, where all the old mine works are, where you get a lot of data, you don't know for sure what you're going to hit.
So
Nate: It's a mystery. It's like a box of chocolates.[00:05:00]
Hazel: Exactly. You bite into it and you don't quite know what you're going to get.
.
So you do as much as you can to figure it out. But firstly, you have to go down there for really quite slowly because you don't want to meet something that you weren't expecting and be, you know, drilling at hundreds of meters a day.
That's just not sensible and you'll just
So you have to be careful. All of this equipment is standard oil and gas drilling equipment. It's nothing special. It's just onshore drilling.
So so drilling down a kilometer, of course, quite slowly takes a big chunk of time, but you think you're adding another four kilometers onto that, you're going to be taking hundreds of days potentially to do that.
And every day you have a drill rig on site, you're adding tens of thousands of pounds, if not more. So
Nate: Wow, okay.
Hazel: that's really the limiting factor. It's all the same equipment. It's not nothing particularly new or shiny and beyond other drilling projects, but it's just the length of time you need to have the drill rig on site.
Nate: Interesting, so it was cost prohibitive in the past, [00:06:00] because it’s too deep. Um not worth it let’s say. We had other types of energy. What policy changes or sort of market force lately have made drilling down five kilometres economically viable?
Hazel: So it's, it's partially been a technological thing. I mean, there has been incremental improvements.
So we are able to do it slightly quicker than we were. You may be aware that actually there was an initial geothermal project back in the eighties here in Cornwall. It's called the hot dry rock project based in a quarry, not too far from here. And they drilled down about two or three kilometers and tested it.
more as a research project than anything else. So it was possible, just not to the scale that we're doing it now. In a sort of policy context, really in the last few years since I joined GEL, there's been this huge increase in in interest in geothermal politically. There are MPs that are all over the country, not just down here in Cornwall, that are lobbying to use geothermal as a new renewable power whether that's just for heating or electricity.
Nate: Wow, okay. So, where else in the UK can you access geothermal energy? I would assume Bath, because I understand there [00:07:00] was hot springs there, but maybe not quite like the hot springs in Japan or Taiwan.
Hazel: No, perhaps not quite the same same temperature or scale. But absolutely, yeah, there are geothermal resources all over the UK in different geysers.
So places like Bath and other sort of thermal springs where they're relatively low temperature at the surface, but they indicate higher temperatures down underneath the ground. So, the key is finding the right type of reservoir in the different locations. So down here, we're looking at fractured granite, and all of the reservoir is hosted within big fault zones.
But in other parts of the country, you could get hot water in mineshafts that are, you know, created by humans in the past. You can get them in you can get them in sedimentary aquifers as well. If you think of just a big sandstone that could host hot water, if you're down deep enough. So there are lots of different locations that could be suitable.
They'll just give you different temperatures.
Nate: . It sounds like geothermal can kind of be a transition industry in a sense, because you were talking about taking these old oil and gas drilling techniques. You know, if you're an oil and [00:08:00] gas person, this might be a viable industry for you.
You can take old mine shafts. Are you seeing that? Are you seeing people kind of come from maybe traditional extractive industries and working on geothermal?
Hazel: Yeah, absolutely. I mean the, the rig queries we use here, they're not a permanent staff of GEL, but we use them and we will continue to use them on other sites and they all come from essentially Aberdeen up in Scotland. So there's this whole North Sea industry that's, that's UK based that we can bring down here and we would.
It's a slow process, but certainly you can see the, the big oil and gas conferences, for example, in the UK are gradually transitioning into talking about geothermal as well because it's very, a very clear link.
Nate: Something else under the ground. Now, with geothermal, you're pulling up water.
This might be a simple question, but what do you do with that water? Do you put the water back down so it can recharge? Or is it, does it need to be disposed of? What happens?
Hazel: Yeah, of course. It definitely varies by location, but here in Cornwall, what we'll [00:09:00] do is re inject it. So it comes up very simply. It's kept under pressure, so it's kept in this, what we call a closed loop.
We extract the heat in a heat exchanger, and then we just re inject it down our second well. So that's why we have what we call a geothermal doublet, which is just two wells, one production, one injection.
Nate: Okay. Let's talk about heating. So there's a lot of difficulties in the UK at the moment about installing heat pumps.
People might be familiar with that from the headlines. It sounds like geothermal is a potential way of offsetting that heating. How would that work? How would we take the heat from those kind of well heads outside and lead that, lend that into people's homes or businesses?
Hazel: Yeah,
so it is something we're working on here at the United Downs project.
What the plan will be at the moment is to extract the heat for electricity. As I mentioned earlier, we have about 188 degrees down at the bottom hole. So once we've extracted heat for electricity generation, we'll still have somewhere between 60, 70 degrees Celsius to then use for other purposes.
This can be re injected straight down into the well, but if [00:10:00] we can use it for something else, that's just a fantastic local resource that we could tap into. So that, say 60 degrees Celsius, can be piped off into a different heat exchanger, which can then go into some kind of heating system, whether that's for like an industrial greenhouse, or whether that's for a large housing development.
It makes a lot of sense in new houses to install this kind of technology straight off the bat. And we're working with Cornwall Council. We've had a project called Langarth Garden Village, which will be about 4, 000 homes being developed over the next few years. And the hope is that hot water from here will be piped there to heat all of their homes. so that's
Nate: Gonna make them almost like a, not like a zero carbon home, but a low carbon home just out of the gates.
Hazel: Yeah. So it won't be the only thing, but they really are hoping to be the UK's first net zero housing development.
Nate: net zero housing development. Wow, brought to you we were talking about the the quartz and the different things you encounter when you're drilling for geothermal wells. What are some of the other things that [00:11:00] you found while you're drilling down?
Hazel: you have to be fairly careful, particularly at the surface around here, because there's a lot of mine shafts, which some are mapped very well, and some are not. You know, some of these mines date back to the 1700s, and the maps are either so disintegrated from use over the years, or essentially just disappeared.
Really poorly drawn, no scale or
Nate: They didn't know what they were doing back then.
Hazel: they did, they just didn't perhaps document it as well as we do these days,
Nate: these days.
Hazel: So, so yeah, that's the first challenge is making sure you don't hit any of these shafts unexpectedly and making sure you engineer your, your system around it.
But that's really only in the top five, 600 meters or so. Going down, you need to be careful for as, as you've mentioned, sort of big, unexpected, sort of, enigmatic features, such as a large quartz boulder, or even void spaces because if there's an unexpected space, you know, you might expect, oh great, that makes drilling easier, but it doesn't.
If it's unexpected, it's, it's really quite difficult for the, the drilling, the sort of, the steerer of the drill to deal with it.
Nate: Sort of like drilling into your wall at [00:12:00] home and suddenly finding a space there.
Hazel: Exactly, yeah.
Nate: Interesting. And we understand that you've discovered lithium. here in Cornwall. Can you tell us a bit more about that?
Hazel: Yeah, of course. So it's actually, it's been known for centuries. I think back in the 1800s, someone discovered high lithium content in some of the mine water around Cornwall. But at the time, there wasn't really any use for lithium. So no one got very excited about it. They reported it in a scientific paper and that was kind of left alone for a couple of hundred years.
Nate: Wow, so a rediscovery then.
Hazel: Exactly. Yeah. So here in Cornwall, there's There's quite a lot of interest in lithium these days, both in hard rock mining, so classic open pit kind of quarries. But recently in the geothermal water that we've we've produced from our wells here, we found around 300 parts per million of lithium in, dissolved in the water.
That's really globally significant.
Nate: That's high.
Hazel: That's very high, exactly, yeah. So I think we were looking at some data from across Europe, and it was the second highest concentration in geothermal fluid across the whole of Europe.
Nate: [00:13:00] Wow.
Hazel: So it's really exciting. And so we're looking at new technologies that will help us extract that lithium from the fluid, because it's not just about getting the liquid to the surface, it's how you then get it out of the liquid.
Nate: Ah, interesting. So it's not going to be like, well, we're going to just do a mine now after we've discovered this lithium.
You're going to take that fluid and pull the lithium out of it. So you're kind of like Like desalination almost, maybe, or kind of like
Hazel: Yeah, that, yeah, either of those are a good way of thinking of it, exactly.
It's lithium likes to stay in the water, that's its natural state, so you have to find a way, and we call it direct lithium extraction, is the kind of group of technologies being explored at the moment. And there's lots of different options out there, but it's all really quite new. A lot of it's sort of lab scale, there's very few working at commercial scale.
So it's yeah, it's an exciting time.
Nate: Hazel, could you gimme sort of a timeline of GEL and how long this process has taken, where it started? Is this, is this a UK company or is this technology from somewhere else?
Hazel: Yeah, of course. So GEL is a Cornish company. It's set up by our founder, Ryan Law, who's now our [00:14:00] CEO. He's a hydrogeologist by background. So he actually worked on the original Hot Dry Rocks project at Rosemanowes back in the 90s. He was a PhD student, so he was doing his research and he found it fascinating and thought, gosh, yeah, we need this technology but something wasn't quite working with the system that had been designed there.
So he went away, did some more research, and decided that actually there's a lot of hot water running through lots of different mines in Cornwall, and yet the, the wells that we drilled at Rosemanowes are dry, essentially. How can that be? So he realized that what we've got to do is target the fracture zones that are here.
There are natural pathways that fluid can flow through and flow up into the mines around here.
Nate: So a little bit like finding natural fracking to kind of talk about like natural gas, like areas where the rocks are already broken up.
Hazel: Exactly. Yeah So all you need to do is tap into that natural fracture and suck the water out of it essentially and then regenerate it as well by reinjecting so he then Went away thought of a new design came back and set up GEL in [00:15:00] 2008.
Nate: Oh wow. So this has been going on for
quite a while, .
Hazel: It has. Yeah. Exactly. So we identified this site here at United Downs in 2010 and then we went through a long process of raising funding. So that took until 2017 to raise enough money to start drilling here.
Nate: Wow.
That's, yeah, that's several. kind of hype cycles when it comes to renewable energy at that point.
Hazel: Exactly, several political cycles. It's a really tough thing to go through. But Ryan managed it through a combination of, of grants from the European Regional Development Fund from Cornwall Council as well. They were really forward thinking and, and invested themselves in this project too, as well as some private investors.
Nate: So what, maybe if we could kind of, Stick to those policy barriers. What what were the challenges created by policy or what were, you know, alternatively, what were some helpful policies that sped this work up?
Hazel: So,
I guess starting from the heat angle, because a lot of people in the UK at the moment are interested more in geothermal heat than in electricity but you think, we used to have something called the renewable heat incentive, [00:16:00] really, really big thing for something like geothermal but that got scrapped a good few years ago now, so there's currently no incentive for renewable heat generation.
Which is a massive part of our carbon footprint as a country, as well as of course our electricity requirements.
Nate: Right, that huge, you know, cost of living crisis. A lot of that is heating costs.
Hazel: It is, yeah, absolutely. We're a cold country quite a lot of the time, so we need a lot of heating. So things like that, no incentivization for that kind of technology has been quite a big barrier.
And it's one that we're still pushing on. Although there is sort of movement towards getting something in place soon. There's also been, so how we get funding from the government for all renewable energy types, not just geothermal, is through the Contracts for Difference scheme. And that is something where you, as a technology, as a site, you bid into it at a certain strike price.
So a pound per megawatt hour of generation. And the government then allots loads of different projects across different pots of money to, to then fund them for the first 15 years of generation. [00:17:00] Now geothermal hasn't been able to achieve getting a CFD until this year, because it's bidding up against wind and solar and a number of other technologies that don't have the upfront cost of drilling that geothermal has.
So we need a higher strike price to make it economic.
Nate: I see. 'cause for a wind turbine, well you might do some drilling in some foundation setting, but it's not like drilling five kilometers down
Hazel: Exactly. For those sorts of renewables, which absolutely have their place, they have quite high operations and maintenance cost, but quite low initial capex.
Whereas we're the reverse. We have almost no O& M moving forward, operations and maintenance cost, but we have very high initial capex.
Alright lets take a break here. So far in the first part we have covered: what geothermal energy is and how it works, the conditions in cornwall and what makes it suitable but difficult for geothermal, the challenges and costs of geoenginnering in the UK, reminder its how much you have to drill, and the historical context of geothermal which has been largely ignored
After the break we will finish up discussing maintenance of geothermal wells, estimates for geothermal potential, how GEL engages with the community, risk management, and the challenges the industry faces towards scaling
Nate: Yeah, what does that maintenance look like? You just have someone kind of check on the well, make sure everything's going on? Do you have to
Hazel: Yeah, yeah, essentially, I mean, I'm no engineer, but essentially for one or two weeks of the year we shut down the plant.
You plan it for the summer period, of course, when heat generation isn't needed as much. And they, they check whether there's any scaling of the within the pipe work from the geothermal [00:18:00] fluid. Just check that everything's working, essentially, you know, take out any of the condensing fans, perhaps, that aren't working quite as well, replacing small bits along the way.
But that's it.
Nate: So maybe thinking kind of in a positive direction, what were some of the policies or supports that kind of led to this moment? Do things like climate emergencies help? Is there interest from corporates in terms of buying renewables? Help me understand sort of what's coming together now to make this viable, not just here, but in other parts of the UK.
Hazel: Yeah, absolutely. So in the last few years when we've really seen that uptake, it's been mostly because of the climate crisis and the energy security crisis.
Nate: Mmm
Hazel: they've both been really important in showing the people, but most importantly, government, both local and national, that geothermal is a viable way forward and a really important piece of the puzzle.
You know, we, we may not be able to generate geothermal across the whole of the UK and enough to, to power every single person out of their houses. But we can give a sort of steady base load of power, which [00:19:00] other renewables like wind and solar just don't offer because they only work when it's windy or sunny.
Nate: Right, the earth just keeps on generating that heat.
They don't know what time of day it is, I guess.
Hazel: Exactly, yeah. So, geothermal plants are sort of generally working around 95 percent of the time.
Nate: Interesting.
So, let's imagine, you know, it's a few years in the future, geothermal's gotten the support it needs. How much might we expect geothermal to contribute to the UK's either national heating or national electricity?
Hazel: So we're starting small. So we'll be the first project and it's more of a demonstration project to show the UK that we can do geothermal electricity. So we'll be generating about three megawatts of electricity, which would be enough to power maybe 5, 000 homes. off the top of my head future projects, so we're scaling up, we're looking at getting four more projects over the next few years up and running they'll be five megawatts.
So again, more like 10, 000 homes roughly.
Nate: okay
Hazel: But looking forward there have been these really big studies recently across the whole of the UK done by the BGS engineering [00:20:00] consultants like Arup and they've estimated that the geological resource is more like 200 gigawatts of geothermal energy that could be tapped into across the country.
Nate: Wow. And what, can you help me understand that in scale of the current sort of renewable energy production in the UK?
Hazel: Oh gosh. Yeah. So we, we did some calculations when that number first came out and it was something like if 200 odd gigawatts would power the whole of the UK like 17 times over if you just look at sort of average house uses and alike.
So there's a, it would be an amazing thing if all of that could get off the ground.
Whilst the geological resource is there, the practical implications of doing these projects all over the UK will take time and money and consideration, which you're unlikely to get anywhere near that number, realistically.
But if we could even get 10 percent of that, we'd be able to power a lot of the UK with it.
Nate: So that's a, that's a massive opportunity there. What are the types of opposition that you encounter? I mean, this, this site, when we drove up, it seemed pretty [00:21:00] inoffensive just looked like kind of, you know, a lot actually less polluting maybe than kind of the nearby industrial facilities.
So what are some of the oppositions you encounter and how do you engage with the community around those?
Hazel: Hmm. Yeah. So you're absolutely right. That community engagement has been one of the biggest parts of this project beyond just the technical feat of drilling so deep. It's been really important that we've had a dedicated community engagement manager from about six months prior to drilling here on site.
So we've had them for about six years now, and what they do is they go out to local interest groups, go out to, you know, church events, summer fetes, any kind of local event you can think of, and just get to talking to the community, you know, gains their trust, shows that we are a local Cornish company, we are doing something for the good of the planet, for the good of Cornwall, and and really gets them on side.
So that has been huge and has fortunately worked really well around this site. We're often shown to be a model of what community engagement should be around this sort of project, even globally.
Nate: Wow, that's great.
Hazel: Yeah, [00:22:00] absolutely.
Nate: So, there aren't many objections then. People, you know, there's no sound, there's no runoff.
Is, is there any kind of opposition? Just maybe, I guess mining maybe? There's some concern there, or?
Hazel: So honestly, here at our United Downs site because of its industrial nature and because we've had such good engagement with the community for so many years, we see very little objection to what we're doing at this site.
However, as I've mentioned, we're looking at future sites moving forward. We've got planning permission for a few others and we're aiming to get planning permission for some more quite soon. Most of these are greenfield sites. They're not industrial. So you're looking at a farm field which perhaps has grazed cattle on before or isn't quite as productive as it once was and we've made an agreement with the landowner to come in and take over that field for this purpose.
So that is quite a different location. It's and it's amazing how How community engagement stays really quite local. Despite our attempts to really get out and talk to as much of Cornwall as we can. Even, you move ten miles away and a lot of people haven't heard of our project. So it is [00:23:00] a new education process at every single site we go to.
Nate: Well, you must be getting quite good at it then.
Then
Hazel: I like to think so.
Nate: So,
you're targeting fractures, you're drilling, there's seismometers. Is there any kind of earthquake risk or any kind of chance of?
seismic disturbance?
Hazel: Yeah, there is. So at any geothermal project around the world we have the drilling phase, in which as you've seen here, it's a very slow process. You go down metres at a time and there's really no chance of any vibration or seismicity being caused by that process. However, the next phase is what we call testing of the wells.
And that means what we do is we inject just plain tap water down the wells, and we see how the reservoir reacts. We measure things like the temperature down there, we measure the, the pressure, and the flow rates we're able to achieve. That's really important scientifically because we need to understand how we can design the power plant to meet the resource that's there.
But what it does mean is if we're injecting water down, even at really low pressures, you can cause movements on the, the faults, the structures [00:24:00] that we are targeting. So that's why we have the, the network of seismometers to understand when the events happen, how, how big they happen, and to make sure that we're not breaching any kind of regulations, because we are regulated for this, the seismic activity by the local planning authority.
So they make sure that any events that we generate are far less than any quarries do around here. We're quite an active quarrying region. And. So what we do is we have what we call a seismic monitoring protocol so that if we generate an event above 0. 5 millimeters per second, that's the amount of ground motion we actually, we reach what we call a caution state and all of us are alerted and we, we sort of monitor and see if anything else happens.
And if it does, then we shut down operations. So it's really quite tightly restricted
Almost sort of self imposition. We can actually work to quite a much higher level but we don't want to risk that.
Nate: Yeah, what, what hypothetically would happen then if, if it was determined that it was going to cause an earthquake or something like that? Would you have to stop the project completely and start over somewhere else? Is [00:25:00] that kind of like a deal breaker or is there something you can do to kind of manage that?
Hazel: It's a peak ground velocity of 8. 5 millimeters per second in a single seismic event. That's what the local planning authority dictates, and that's what we work to. And if we start going over that, then yes, absolutely, the project can be shut down.
Nate: Wow.
Hazel: So it is something that we have to be very careful about.
But to be honest, more than that, because that's a really big event, and that is, you know, we, our maximum we ever got was 0. 8 millimeters per second. So an order of magnitude less. It's more the public perception that is the concern. So there have been projects all over the world places like Taiwan Basel in Switzerland that have had really large, unexpected seismic events.
We're talking magnitude 5 on the Richter
Nate: Oh wow, okay, you'll feel that.
Hazel: you will. That has destroyed the industry in that country, they, they haven't been able to move forward with geothermal. So you know, it's really important that the public understand that seismicity will happen.
It's something that's very tightly managed and it will never be any [00:26:00] danger to their, their homes or, or themselves at all. So, but if if the public started growing more concerned about it, the planning authority obviously have to step in as well.
Nate: I see. And so then one response to that might just be drilling more slowly or, yeah, I guess. Do you have to just pick a new site?
So
Hazel: So you'd have to change your injection strategy perhaps during testing. That would be really the the thing that controls the seismicity that's happening. If, if some large event were to, to happen then it, yes, you may have to, to move locations.
Nate: But once it, so then once it's drilled, there's no further risk of earthquakes, or any kind of seismic activity
Hazel: Once it's tested, yeah, so you do the drilling, you won't get any seismicity. You do the testing, that's your seismicity period, realistically. Once you're operational, you think you're sucking up water, and you're putting the same water back underground. You've got this closed loop, the pressure isn't changing, the system is, is almost in balance, as it were.
And that means that you won't, you're very, very unlikely to get any seismicity.
Nate: All right. Interesting. Very [00:27:00] clear.
Hazel: I mean, it's, I guess it's worth noting that here at United Downs the primary aim was always to generate electricity and prove that electricity was possible to be generated from geothermal in the UK. But as we've moved on, as new opportunities like the Langarth Garden Village project And, and like the discovery, or the rediscovery of lithium has come on, you know, it's really shown that geothermal is not, is, you know, not a one trick pony.
There are multiple uses that we can have for this single local resource. So it's become more attractive commercially of course but it's become more attractive because it takes up such a small area and yet can be used for so many things that can bring benefit to, to Cornwall in this example.
Nate: As we've been talking to people in Cornwall, we've heard that there's a lot of green skills gaps that could be plumbers or electricians.
Do you run into that with geothermal? Are there enough people here who have the skills to be able to work on this project? Or is there a training gap? Help me understand
Hazel: yeah, of course, so we're really lucky down in Cornwall and that we have a university called the Camberland School of Mines Which is actually a [00:28:00] part of the University of Exeter.
So that's local that's down in Penryn It's just a few miles away from here and that churns out a lot of geologists They have a renewable energy Institute even as part of that And so there's there's quite a lot of skills on that side locally and potentially anyway
What we do lack is engineering skills, I would say.
They're really all locked up in Scotland because of the North Sea projects.
Nate: Ah, interesting. So Already drilling somewhere else.
Hazel: Exactly, yeah. So that's the major, major gap. And I think because Cornwall is traditionally thought of as a sort of summer destination, it really is seasonal work down here.
So even though we have the potential pool of geologists somewhere like the Kanban School of Mines, a lot of them don't even think that they could get a job down here. You know, a lot of them will go up country into the rest of the UK or abroad to big mining projects in Australia, for example. So it is, it is difficult.
You know, and being a, a seasonal location means that. Quite often it's a bit tangential, but quite [00:29:00] often house prices and rental costs are really quite high because of the tourist market. So, you know, you're looking at graduate entry level roles, they're not going to be particularly attractive in a location where rental market is quite high.
Nate: Oh, that's an interesting challenge. Yeah, we've noticed in several pubs their prices are more like London prices rather than
Hazel: It's really surprising. Yeah, absolutely. There's some which is very local and kept very reasonable. But yeah, you go anywhere near the coast and you're back up at London prices.
Nate: So there's the people, there's the training centers, there's the opportunity, they just might not think that Cornwall's the place to be if you're into mining or geology.
So it's about kind of spreading that message and letting people know that, you know, if you have these skills, there's work to be done.
Hazel: Yeah, partially. And then I mean, as our industry goes and, and other adjacent sort of subsurface industries, there's a lot of what I call indirect jobs, you know, not directly working for geothermal engineering, but perhaps The contractors that we use for scaffolding or even the places where if we [00:30:00] have to bring in outside contractors, they stay in accommodation, they eat food, they have to go to all of these different places for hospitality and use different equipment.
So there's all these other businesses of all different types that are also then Gaining jobs. They need more people to bring on to to support us. So there are all these adjacent opportunities as well Things like pr and social media, of course is a big thing these days people don't think about but we need it Even as a small company, so there are lots of these slightly odd maybe unexpected opportunities coming through.
Nate: That's interesting. So geothermal is in some ways kind of bringing back some of these secondary economic sectors that maybe used to support the mining industry here when it was more viable. So it's kind of like a, a second mining boom, maybe not, not quite a boom yet, but
Hazel: Yeah, I kind of affectionately call
I affectionately call it a subsurface renaissance.
Nate: That sounds like I'd like to go to a subsurface renaissance fair
Hazel: That would be interesting.
Nate: How we doing, David? I think we, I think we got a lot.
Yeah.
Hazel: Yeah. Because
Nate: we're, we're going to put this together with the writer [00:31:00] as well. So,
Hazel: Yeah, of course.
Nate: Okay.
Hazel: Although, I think, could we go back because outside on the roof, the wind was
Nate: blowing a bit, I think you were talking about
Hazel: the site
Nate: and
Hazel: what it looks like now versus
Nate: when the power plant
will, yeah.
Okay, yeah. So just, could you describe the site and?
Hazel: Yeah, and
Nate: what's
going to happen over the next year, Okay. So Hazel, could you paint us a picture for our listeners what the site looks like now and what it will look like in the future once it's fully operational?
Hazel: Yeah, of course. So we sit, we're quite an unassuming site. We're a small plot about 5, 000 meters within an industrial estate.
So we've got lots of people around us from sort of welding companies and gas companies, things like that. So we sit in quite a, an unassuming location. And essentially it's just a gravel covered rectangle. In which we have two wellheads in the centre, and they're about eight metres apart, so really quite close.
One is our, our deep well, UG1, which goes down more than [00:32:00] five kilometres, which actually goes down vertically from the site, but then deviates under our office building over into the valley nearby. So at the moment, really all we have on site is some storage containers. These wells in the middle, of course our offices, and a storage pond where we can, when we've done our testing, we've emptied the wells into that storage pond.
However in the future we'll be taking up quite a lot of the rest of the site with the power plant infrastructure. So these well heads in the middle will be connected via pipes into a heat exchanger. And this will have what we call a working fluid within it. And this working fluid will then go into a generator and a turbine.
And then be cooled in a bank of condensing fans. So really the biggest feature on the site will be these condensing fans. And that's it.
Nate: that's pretty low impact.
Hazel: Yeah, absolutely.
Nate: is your job. Yeah, great, great, great descriptions. Yeah, alright. Thanks so much Hazel for taking the time to speak with us today and tell us everything about geothermal, the potential, the [00:33:00] challenges.
A little bit of the history, the skills. It's, it's really been awesome and I'm really excited about the future of geothermal in the UK.
Hazel: Thank you, so am I. Appreciate you guys coming.
Nate: Alright.
We are also excited about the potential for geothermal, not just in the UK but all over the world, well all over the subsurface with hot rocks nearby.
Right now is such an exciting time, we get new types of renewable energy coming online in places that have never had them before. Instead of adding pollution to the atmosphere geothermal takes advantage of excess heat below the ground to help us avoid our own heating costs and we can even get minerals as a bonus with new geothermal techniques.
In the next episode we will speak with CEO Ryan Law about the economics behind geothermal energy and what a geothermal CEO has to work on. His journey gives us a lot of good insights into the challenges energy entrepreneurs face with new technologies and the uphill battle to bring subterranean energy to the surface.
I'm Nate Maynard and this is Netting Zeros, recorded in London and onsite at United Downs in Cornwall.
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Thanks for listening. Keep netting those zeros!