Turning up the heat on geothermal power

The Scottish Government first explored the potential for deep geothermal as an alternative source of energy over a decade ago.

Itis a type of renewable energy created by the heat found at the earth’s core. It is extracted through drilling, and it is then used to generate electricity and heat homes amongst other uses.

Unlike other forms of green energy such as wind and solar power, geothermal provides a consistence source of energy as it is not dependant on the weather, making it a critical part of the future renewable energy mix.

In 2013, the government commissioned AECOM to look into deep geothermal, and it’s study found more than 200 Scottish oil and gas supply chains were capable of diversification into the geothermal supply chain. However, it warned that a strategy and a vision statement were required for the geothermal sector to see any significant development.

More than a decade later, shifting from high-emission energy sources towards low-carbon energy sources has become essential to reaching key climate change targets. Yet, the Scottish Government is still to publish a comprehensive strategy or a vision statement on how it will unlock the full power of deep geothermal.

And although 32 deep geothermal projects have been launched across the UK, evidence shows we are only exploiting a fraction of its potenial, with research by the Durham Energy Institute (DEI), estimating the UK has sufficient deep geothermal resources to satisfy its heat demand for at least a century.

Holyrood spoke to Charlotte Adams, director of the National Geothermal Centre (NGC) – the UK’s first national centre to advance geothermal energy, on what the sector’s role is in helping achieve net zero and in ensuring energy security.

Co-funded by the Net Zero Technology Centre (NZTC), the project aims to help fill the regulatory, research and expertise gap in the sector.

Scotland aims to reach net zero by 2045, five years before the rest of the UK. How much of a role can geothermal energy play in reaching this?

I think following the growth in other nations that have similar geothermal resources to the UK, we would expect to see an annual 10 per cent growth in geothermal heat uptake. Although there’s been a lot of success in decarbonising electricity, with the uptake of wind, solar and nuclear energy decarbonising heat remains a big challenge with not that many low-carbon technologies that can work at scale to address that challenge. However, the heat decarbonisation challenge aligns well with what geothermal can offer, as it could be used for heating, cooling, and storage.

And, cooling is becoming increasingly important, especially with things like data centres. So, although we might not need a lot of domestic cooling yet, the need for cooling in industry is growing.

If geothermal benefits are so clear, why is it taking so long for geothermal to be one of the it not one of the focal points of discussion in Scotland’s net zero journey?

I think the upfront cost and risk have always been perceived as a challenge to geothermal development. However, once you've got over that, and you've got your geothermal terminal system in place, it's there for a very long time.

I also think a lot of people don't realise that the resource is there and the benefits it has, including being predictable, and controllable.

Another key thing is it uses proven existing technology.

For example, there are still questions being asked regarding hydrogen whether it would leak and where it would leak if it was introduced into the gas network. So, we know the technologies for producing hydrogen from a green source are probably a lot less technology-ready than that of geothermal. At the moment, in its most basic form, it uses borehole drilling, which both the water and oil and gas sectors have been doing for many years, and heat pump technology, which has been around since the 1950s.

So, it's a lot more technology-ready. But, the problem comes back to the upfront cost and risk.

Also, there's not really been a voice for it before. When I worked in the coal authority, we couldn't lobby for it because we were a government organisation. On the other hand, there are some quite powerful lobbying networks in some of the other energy sectors.

Has the cost and risk associated with geothermal energy made it difficult to develop the industry?

I think it's one of the challenges. Other nations with similar resources to the UK who have developed their geothermal energy sector further, tend to have three things in place. They have a sort of feeding tariff or renewable heat incentive, so they earn income from every kilowatt hour of geothermal heat they produce. They have an insurance scheme against geological risk, so if you drill and don't find what you're expecting, the scheme covers that. And their access to data is also a bit more widespread.

In the UK, we only have one of those things at the moment - access to data. The Renewable Heat Incentive (RHI) for geothermal was removed a couple of years ago and we don't have risk insurance against geological risks. So, I think talking to the countries that have worked for those three things [incentives, insurance and access to data], and then advocating for the same kind of approach here, will help to improve investor confidence.  

The Scottish Government recently scrapped its 2030 climate target. Do you think if we had explored the opportunity offered by geothermal energy, this could have been avoided?

I think it's always good to have done something earlier. Personally, it's something that I wanted to do 20 years ago, but obviously, the economic climate wasn't right at that time. I think it could have helped towards our heat and decarbonisation ambitions for Scotland, which is a tricky challenge because the use is so disparate, and cuts across a lot of different sectors from domestic to industrial to municipal.

A lot of the other renewable technologies produce electricity, whereas geothermal is predominantly used for heat, hence helping our heat decarbonisation challenge.

It's also continuous, and secure. It generally has stable temperatures, which means you can predict the output. So, if you're a business looking to sell heat, geothermal enables you to predict your income from sales, and offer secure pricing.

And as heat doesn’t travel that well beyond the heat network, it has to be used locally, giving local benefits to people. Whereas you could argue when something like coal was being mined, it was mined, traded, and burnt, and all the people in the area where the mines got employment, there weren't any longer-term benefits. So, the fact that the heat has to be used locally is a benefit.

Earlier this year the Scottish Government published guidelines outlining the regulatory framework for “exploring and exploiting” Scottish geothermal resources. However, this was only a “point of reference”, and was not “a comprehensive list of all legislation” relevant to geothermal heat projects. Would you say that bureaucracy is slowing down the geothermal energy sector? If so, what would a good policy framework look like?

We must first look at where regulation is needed to avoid the risk of over-regulating the sector.  I mean, geothermal is an embryonic industry. At the moment, there aren't many installations, so how much do we actually need to regulate?

Unfortunately, we currently don't have any bespoke regulations for geothermal. It is fitted into other things, mainly water regulation. And although it's not preventing projects from happening, there needs to be regulation more tailored to geothermal. For example, geothermal schemes generally don't consume water, but a lot of the water regulation is geared towards abstractions and does not tackle water going back in and there might be temperature changes between the water you take out in the water you put back in. So, I think regulation could be more streamlined so that the developer wouldn't have to go to several different bodies to get all the approvals.

So, a good policy framework would be created by a good consultation period with our network to get the necessary policy changes made that will support the development and provide sound evidence to show what new policies would bring about.  

You mentioned having sufficient energy as being essential to stop us from depending on other countries. The NZTC is currently carrying out a project to export hydrogen energy to Germany. However, you have just said that geothermal energy is to be used locally, so what are the supply chain opportunities it offers?

I think certainly in terms of the supply chain, there are opportunities to export our skill set. The water and oil and gas industries have a lot of the skills that will be directly transferable to geothermal, particularly around drilling, where we have abundant expertise in the northeast of Scotland. So, there is an opportunity for that to be shared globally, as well as demonstrated nationally.

I'm also aware of UK-based multinational companies looking at geothermal because gas heating in the UK has become expensive. So, geothermal offers an opportunity to keep business in the UK while also attracting new business.

What would happen if we didn't take advantage of this geothermal opportunity we have right now?

Well, the nation is becoming increasingly reliant on energy imports, and as an island nation, this leaves us at risk for geopolitical shocks that could impact energy supply in future. It would be more difficult to meet our net zero targets without geothermal as it aligns well with the heat decarbonizing challenge.

We have already faced an energy crisis and a significant cost increase. So, if we can produce more of our own energy, whether it is from geothermal or other low-carbon sources, we will then have more control over pricing.