Mon, 15 July, 2024
Belgian geothermal stakeholders met GeoSmart project partners in Brussels on July 4th during a workshop co-organised by VITO and EGEC. Held as a parallel session to the larger EU Geothermal power event, the workshop focused on the Belgian geothermal sector while also addressing broader topics.
The workshop aimed to introduce Belgian stakeholders to the GeoSmart project and its innovations, discussing their potential to address challenges in managing geothermal resources in Belgium.
Namrata Kale from TWI provided a general introduction to the GeoSmart project. This was followed by presentations from pilot site leaders Zorlu and VNI on innovations for both low and high enthalpy geothermal projects.
Ural Halaçoğlu from Zorlu updated on GeoSmart activities at the Kizildere II Geothermal Site. Innovations to address silica scaling and thermal energy storage were detailed. A system using a scaling reactor and retention tank was designed to manage scaling in a controlled environment before fluid injection. For thermal storage, a phase change material (PCM) heat exchanger and steam accumulator were chosen initially. However, after having technical discussions and feasibility studies, steam accumulator installation was cancelled. Mechanical and electrical site works are ongoing, with most civil works completed. The scaling reduction system and PCM tank are installed, with secondary items in production. The system is expected to be commissioned by the end of September and tested for at least two months. While these innovations are primarily for high enthalpy geothermal resources, Belgian stakeholders acknowledged their importance in such contexts.
Gawan Berentelg from Natürlich Insheim discussed innovations for low enthalpy geothermal plants, highlighting the Insheim plant in Germany. He presented solutions for flexible heat supply for district heating and ORC using thermal energy storage. At Insheim, a 90 m³ thermal energy storage system (160°C, 8 bar) is being tested to enhance plant flexibility and district heating redundancy. Further, since it is known that air-cooled condensers limit power production at high ambient temperatures, GeoSmart's high-pressure ultra-fogging technology below the air-cooled condenser (so-called adiabatic cooling) was introduced to improve the efficiency of power production. However, note that the adiabatic cooling method used in Insheim is not feasible in Belgium due to restrictions on water spraying and dissipation without reinjection. Although geothermal heat production is the main current focus, and no ORC plants are in operation in Belgium the thermocline storage could be an interesting solution to improve both the flexibility of heating and power production of geothermal plants and the redundancy for district heating systems.
The workshop then focused more on the Belgium context. Ben Laenen (VITO) presented an update on Belgium's geothermal market and its potential. Despite existing deep geothermal potential, its use remains limited, with a focus on heat production due to low to mid-enthalpy geothermal conditions. Belgium currently has five operational plants (Saint-Ghislain, Ghlin, Douvrain, Mol, Beerse) with a total heating capacity of 37 MW, of which 14 MW is not used In 2023 the 5 plant provided 27GWh of heat. 6 plants are under development or under investigation. Regional targets for heat delivery from deep geothermal inh2030 are 99 GWh/y in Flanders and 251 GWh/y (including mine energy) in Wallonia. The Walloon region is actively funding large exploration projects to enhance subsurface knowledge and accelerate deep geothermal deployment. In Belgium, there is an interest in provinces outside the traditional exploration areas. The developments in parallel to the standard doublets include geothermal heat extraction and thermal storage in deep mines, exploration of deep geothermal potential in the crystalline basin (Exploration license Wiesbeke) and single well systems in hot dry rock.
Ben Laenen also discussed thermocline storage's impact on Belgium's geothermal context. Theoretical modeling applied to VITO's plant showed increased efficiency (up to 5% more heat and less brine produced annually), but also higher levelized costs due to depreciation and maintenance of the thermocline. Careful case-by-case assessment of thermocline storage's added value is necessary, with consideration of alternative, cheaper solutions.
Johan Van Bael (VITO) highlighted smart and innovative control strategies to increase flexibility in district heating networks. He presented the STORM District Energy Controller, an AI-based control system developed by VITO that optimizes network operation by leveraging the thermal mass flexibility of buildings without compromising service quality. Also the further innovations related to the STORM district energy controller have been presented. Johan Van Bael also mentioned the follow-up Horizon Europe projects of the h2020 Geosmart project:
- PUSH-IT Focus on the use of the underground (ATES, BTES and MTES) to store heat and demonstrated in 3 demo sites. 3 innovations: 1/ Enhanced drilling & water quality control, 2/ Social justice & regulation and 3/ Optimal system integration & control to be tested at 3 demonstration sites.
- HOCLOOP Development of new drilling technologies, an environmentally friendly geothermal solution using a horizontal closed loop, alternative circulation fluids, scale test operation to TRL5 and development of models for heat flow simulations.
- Push2Heat Focus on optimizing four heat upgrade technologies, market potential, new business models, and demonstrating four full-scale pilot plants in various industrial applications..
- nGel project “Next generation flexible tri-generation geothermal ORC plant”. (Start June 2024)
Additionally, Van Bael mentioned the VLAIO-funded project iamhex focusing on "Revolutionizing Heat Exchanger Design, Optimization, Manufacturing with 3D printing, and Testing."
Finally, to conclude the workshop, Wilfried Bero (VITO) presented the results of a national consultation with key geothermal stakeholders from the GeoSmart project. The interviews revealed that heat production is the primary focus for geothermal energy in Belgium, particularly for district heating networks and the aquaculture, horticulture, and agro-food industries. Greenhouse horticulture is a growing market in Belgium and presents a significant opportunity for decarbonizing the heat supply. Currently, combined heat and power (CHP) systems in this sector are primarily powered by natural gas, which contributes to greenhouse gas emissions. Geothermal energy can play a crucial role in reducing these emissions by providing a sustainable and renewable heat source. However, the main challenge lies in adapting geothermal solutions to fit the needs of such small, family-owned businesses. To achieve this, securing Heat Purchase Agreements (HPAs) is essential, ensuring that these businesses can reliably access and afford geothermal heat.. Stakeholders emphasized the importance of public acceptance and identified several challenges: the need for political support, limited reservoir extensions, underexplored areas requiring seismic exploration campaigns, subsurface data transparency, space constraints for permits, and the necessity for new technologies for large-scale deployment.
The workshop provided the participants with valuable insights into market opportunities, and innovative solutions driving the future of geothermal energy. This event attracted about 50 participants and fostered collaboration and knowledge exchange in the Belgium geothermal sector and beyond.
(Article published courtesy of VITO)
This project has received funding from the European Union's Horizon 2020 research and innovation programme. Grant agreement 818576.