Keywords

1 Introduction

A key ambition of the European Green Deal is to supply “clean, affordable and secure energy” (European Commission, 2019, p. 6), which has been bolstered by measures to rapidly diversify and roll-out renewable energy technologies in the REPowerEU planFootnote 1 (European Commission, 2022). In this context, geothermal energy has a major role to play in moving the EU away from our reliance on gas, as recognised in the Revised Renewable Energy Directive in 2023 (European Union, 2023), yet it is not currently realising its potential across Europe. At the same time, the European Green Deal aspires to a “just and inclusive” transition (European Commission, 2019, p. 2) where communities and citizens can work in partnership with institutions and organisations in energy decision-making. However, societal engagement tends to be neglected in strategic documents on upscaling geothermal technologies, e.g. the recent Implementation Plan of the Geothermal Implementation Working Group only mentions communities in passing (Geothermal IWG, 2023), and inadequate engagement risks eroding the social legitimacy of geothermal energy and may limit the potential to achieve just transition ambitions.

To address the challenge of increasing the uptake of geothermal energy whilst including communities in energy decision-making, we assembled an interdisciplinary team of international experts, representing several areas of Geoscience (including Geophysics, Subsurface Exploration, and Predictive Modelling); Science Communication; Citizen Engagement with Research and Innovation; Environmental Social Science; Social Geothermal Sciences; Human Geography; and Environmental Sociology.

Over the course of four months, we engaged in iterative mutual expert elicitation (i.e. gathering expert knowledge and judgement) through several preparatory virtual meetings, followed by a face-to-face, in-depth interactive workshop to tackle three key themes: (1) understanding different types of geothermal technologies and their associated risks and benefits, (2) how to advance the role of society in transition to climate neutrality, and (3) how to increase engagement at a project level, given the specificities of geothermal projects. In our face-to-face workshop, we worked through disciplinary definitions of key terms and exchanged knowledge of state-of-the-art research—materials which were co-produced at the workshop, including mind maps, are available open access (Rohse et al., 2024). Our mutual expert elicitation enabled us to understand disciplinary knowledges and how disciplinary siloes may be bridged.

At the Geoscience end of the spectrum, we explored the complexity of geothermal technologies, their specific risks and mitigation measures, and discussed how the initial set-up can be costly and lengthy. We also observed how the Social Sciences tend to be neglected within geothermal projects, uncovering how top-down approaches to engagement (e.g. those focused on information sharing) tend to dominate. From the Social Science perspective, we unpacked many different understandings of engagement, and discussed examples of good practice, both from within and outside the geothermal sector. Our key learning concerns the abstract nature of Social Science frameworks and the need to translate them into practice. Our interdisciplinary encounter therefore allowed us to consider those abstract frameworks in the ‘real-world’ context of several geothermal technologies.

As a result, we provide recommendations on incorporating societal engagement throughout geothermal project developments aimed at: (1) decision-makers at EU and national levels, as they set national energy agendas and should be responsible for giving societal engagement an equitable place in policymaking, (2) local and regional decision-makers, as they plan and implement local energy plans, and 3) geothermal operators across Europe, as they propose and implement projects.

In the main body of the chapter, we outline (1) current understanding of geothermal technologies, (2) how geothermal energy may be introduced in EU, national and local energy decision-making, and (3) how societal engagement in geothermal projects can become more inclusive.

2 Technology and Society in the Geothermal Sector

2.1 Understanding Geothermal Technologies

One goal of our interdisciplinary encounter was to ensure that we shared disciplinary perspectives on geothermal technologies, including their diversity and their associated opportunities, risks, and challenges. This enabled us to consider how these specificities may play out in practices of societal engagement, as we explore below.

Geothermal energy can be found everywhere. It is a non-intermittent flexible resource, which offers promising opportunities in the renewable energy landscape. Geothermal technologies provide a sustainable energy source, with generally minimal greenhouse gas emissions and a light environmental footprint overall. In terms of societal perceptions, we hypothesise that the low-carbon nature of the technology could make it appealing, bearing in mind that opposition to another subsurface technology, hydraulic fracturing for shale gas exploitation, has been partly driven by concerns about the impacts of fossil fuels on the climate. Indeed, in our experience in the UK, geothermal energy has appeared to have a receptive welcome, with community members near some UK geothermal sites reflecting on how geothermal energy can help shift us away from a reliance on fossil fuels. However, we acknowledge this is only part of the picture. Whilst, as a subsurface activity, geothermal energy is almost invisible and takes up a relatively low surface area, there are impacts related to surface operations (e.g. land occupation, visual impact, noise) that could affect local communities, and raise concerns over the distribution of costs and benefits of these developments.

There is a diversity of applications for geothermal energy, which can be harnessed for electricity generation, heating and cooling, hot water, and minerals supply (e.g. lithium). This diversity of applications means that the range of risks and impacts are broad and vary. However, the environmental risks and technical challenges associated with geothermal developments are well-documented and mitigated thanks to regulation and best practices (Chen et al., 2020; Gombert et al., 2018). For example, geo-mechanical changes (e.g. seismicity) and underground changes (e.g. disturbance of non-targeted aquifers) both require careful monitoring and mitigation. In terms of societal engagement, some of our research in the UK shows seismicity was a concern in other subsurface sectors (Ryder et al., 2023). Yet, seismicity (and other environmental risks, like chemical leakages) is not a risk for all geothermal applications. Therefore, we highlight the importance of developers being clear and transparent about risks and mitigation for proposed technologies as paramount for trust-building and engagement.

In addition, financial challenges exist. Initial drilling and exploration can be relatively costly and lengthy, which makes attracting investment challenging, especially as the uncertainties relating to variability of the underground and to gaps in knowledge tend to be high before drilling and can remain significant during operation. The length of time it can take for geothermal projects to be set up and completed can have implications for engagement. On the one hand, a longer process provides opportunity for more engagement; on the other hand, supporters may eventually lose faith in a project ever coming to fruition.

2.2 Introducing Geothermal Energy in EU, National and Local Energy Decision-Making

The growth of geothermal technology holds the potential to significantly contribute to a cleaner and more sustainable energy future. Yet, public awareness of geothermal technologies is low, and societal engagement in geothermal developments tends to be top-down and focused on acceptance. This is in contrast with EU efforts to make citizens’ voices heard (e.g. via the Conference on the Future of EuropeFootnote 2), including specifically on the transition to climate neutrality. As a result, we propose that (1) policymakers should support initiatives to make energy decision-making more inclusive, ensuring that geothermal is appropriately represented in deliberation processes on energy futures at EU and national levels, and in deliberations about local technology choices, and (2) that operator- and developer-led engagement can be bottom-up and inclusive (see Sect. 3.2.3). We start by exploring the first of these below.

Public deliberation exercisesFootnote 3 are proliferating in Europe at various scales—for example, national climate assemblies, such as in Denmark (The Citizens’ Assembly on Climate Issues, 2021), and at regional level, such as in Lombardy, Italy (Simone et al., 2023), to collectively design the path towards carbon neutrality, and align public strategies and actions to the views, needs, and concerns of communities. This type of broad societal engagement can enable a more inclusive and just energy transition. For example, it can contribute to setting goals beyond electoral mandates, giving legitimacy to public authorities’ choices, and building trust and alliances between different societal actors.

We argue that EU and national policymakers should support public deliberation exercises on the future of energy in which geothermal technologies are presented within a range of potentially viable options. This is necessary due to the geothermal sector being at an earlier stage of expansion compared to other sectors. Indeed, there are practical challenges associated with representing a full range of energy technologies at an appropriate level of detail to communities (Elstub et al., 2021). As such, less common technologies such as geothermal ones may be at a disadvantage when compared to more mainstream options with which the public is more familiar, and where more evidence about effectiveness exists.

The relative novelty of geothermal technologies means in some areas, the potential economic, environmental, and system benefits may be unknown or unclear. Similarly, the novel nature of geothermal projects means that perceptions about associated risks may not be based in real-world experiences or may be affected by ‘spillover’ from other projects, where negative perception of other energy projects lead to negative perceptions of geothermal projects (Westlake et al., 2023). As such, there is a need for objective evidence to help guide decision-making processes, whilst also recognising and valuing knowledges and expertise from within communities, such as local underground knowledge (Ryder et al., 2023). Deliberative processes are ideal to bring those different types of knowledges together.

In addition, deliberative exercises have the potential to support communities in identifying appropriate geothermal opportunities at a smaller scale. Local authorities have a major role to play in this process. For instance, they can have identified geothermal energy as a technically viable option for local heating or cooling, and they need to work with local communities to establish whether it is a socially viable option, as in St. Gallen, Switzerland (Ejderyan et al., 2020). Within such processes, technical assessments must be transparent, emphasising a holistic view of potential risks and benefits across a project life cycle, and include different technologies to ensure that decision-making is informed and balanced. When this is enacted, communities can make informed decisions about future energy provision, including whether geothermal energy is ‘right’ for them and under what conditions, which deliberative and co-creative processes can help identify. Accepting the decisions that emerge from societal engagement, including if they reject a project or a technology, is essential.

Whilst there is a role for EU, national, and local policymakers in large-scale deliberation on the future of energy, or small-scale deliberation on local energy plans, geothermal projects are for the most part developer- and/or operator-led. In the next sub-section, we draw on our team’s experiences with existing practices of engagement in geothermal energy, drawing attention to important considerations for developers and operators to widen their approaches to societal engagement.

2.3 How Societal Engagement in Geothermal Projects Can Become More Inclusive

As an author team, we collectively have in-depth experience working in several European contexts. In our workshop, we identified that the development of geothermal energy is inherently intertwined with local socio-economic contexts, and that societal engagement requires a case-specific approach. At the same time, through our international and interdisciplinary experience, we established the collective importance and desire for inclusive engagement to move the geothermal sector forward. Here, we provide examples of bottom-up and inclusive approach to societal engagement in the geothermal sector.

To our knowledge, a mark of success in geothermal developments is the ability to establish and sustain a high level of community trust and support. This achievement is directly tied to prioritising meaningful dialogue in the engagement process and leveraging mutual benefits. Fostering trust, which is closely connected to co-production and psychological identification with a project at the community level, is key in societal engagement and negotiating a “Social License to Operate” (Barich et al., 2022). A notable example is Iceland, where communities view geothermal projects not just as energy initiatives but as integral contributors to their well-being. Iceland has become a hub for knowledge transfer, capacity building and geothermal outreach. This has stemmed from a culture of open collaboration between sectors from within the country, which is being consciously maintained through meaningful dialogue with local communities and stakeholders.

How operators view, approach, and support communities, their willingness to be honest about risks and unknowns, and the way they accommodate and reduce community impacts are ways that industry-community relationships have been strengthened (Ryder et al. under review). One UK example of this is when an operator chose to use a more expensive drill because of the noise reduction it would provide, reducing local disturbance.

Community-led geothermal initiatives, such as those in Madrid, Spain, (Hildebrand & Klein, 2022) and in Darmstadt,Footnote 4 Germany, are examples of residents coming together to shift their heating sources from fossil fuel to geothermal energy, reflecting a desire for greener technologies and heat supply. This demonstrates that under the right conditions, bottom-up projects are possible, and highlights the need for the industry to be visible and approachable to facilitate such participation in the energy system. Relatedly, alternative financial schemes such as crowdfunding for geothermal projects (e.g. Friederichs, 2021) can highly influence the deployment rate of geothermal energy.

However, there are some barriers for operators to gain community support. For instance, although several projects in the Upper Rhine Graben (e.g. Soultz-sous-Forets, France) proved their efficiency, poor project management and lack of transparency led to failure in other similar projects (e.g. Vendenheim, France), and strong rejection from local communities (Chavot et al., 2018), destroying trust in the sector in that area for years. Even in the positive examples of the UK, one operator who had previously engaged their community extensively faced pushback to a new project, in part due to a lack of in-depth engagement. This demonstrates the importance of early and continuous engagement within a project, and from one project to the next.

3 Achieving Our Recommendation

As per the title of this chapter, our core recommendation is that policy should prioritise inclusive, early, and continuous societal engagement to maximise the benefits of geothermal technologies.

Through our STEM-SSH collaboration, we have uncovered how the technical specificities of geothermal technologies and the social challenges they face intersect, and require interventions across scales from EU, national, local policymakers, and operators to ensure that the potential of geothermal energy in decarbonising heating, cooling, and electricity production can be realised, meeting the ambitions of the European Green Deal and the REPowerEU plan for renewable energy technologies in a way that is fair to European communities.

Our iterative elicitation process enabled us to rapidly gain knowledge across disciplinary divides to identify points of connection between social and technical challenges, which led us to identify how several actors can support societal engagement specifically in geothermal developments, and recommend that policymakers and industry operators should prioritise inclusive, early, and continuous engagement across scales to maximise the benefits of geothermal technologies in the quest to supply clean energy across Europe (European Commission, 2019), whilst “promot[ing] the participation of local communities in renewable energy projects” (OJEU, 2023, p. 8).

At the local level, several examples in the geothermal sector demonstrate that valuing, resourcing, and implementing inclusive societal engagement is possible. Tools such as community-led initiatives, alternative modes of financing, deliberative energy decision-making and the Social License to Operate framework are ethical and transformational tools that can help broaden our understanding of societal engagement that can mutually benefit the geothermal sector and communities. However, these are scattered examples; embedding inclusive societal engagement requires formal support through EU, national, and local policy instruments in the process of scaling up geothermal technologies. To advance geothermal technologies as part of a fair energy transition, EU and national policymakers should mandate that energy decision-making processes be more inclusive, supporting both wider deliberation on the energy transition where the geothermal sector should be appropriately represented, and the inclusive engagement of local communities in geothermal projects at local and regional scales.

Local and regional policymakers should plan and implement inclusive societal engagement that goes beyond the minimal requirements of consulting and informing at planning stage, to incorporate processes of deliberation and co-creation with local communities. Whatever the mechanisms adopted, accountability of commissioning authorities is key. Anchoring engagement methods within public strategies or policies can help to ensure that public authorities act on co-created outcomes, making communities feel heard, which contributes to the credibility of such exercises.

Geothermal industry actors should practise inclusive societal engagement, which is early, continuous, and sensitive to the technical specificities (e.g. local resource; subsurface uncertainties) and social challenges (e.g. low public awareness) of geothermal technologies. Given the degree to which geothermal heating and cooling rely on local use, engagement with local communities is especially important for geothermal technologies. This local focus also opens doors for the possibility of more equitable distributions of the burdens and benefits of resource development. It is possible to expand the geothermal sector in a fair and inclusive way through: transparency about our understanding of the risks involved and of mitigation measures; designing projects addressing community members’ expectations; maintaining meaningful dialogue; creating local benefits (e.g. local employment opportunities; domestic value chains); and establishing community-based projects. All of these require STEM-SSH collaborations.