Reducing energy consumption with innovative solutions: is the answer beneath our feet?


In a constantly developing world, with a rising population and technological developments, we need energy. Energy and environmental problems are closely related since it is nearly impossible to produce, transport, or consume energy without significant environmental impact.

European energy consumption escalates annually, with buildings responsible for half of the total usage. Residential sectors heavily rely on energy for space heating, cooling, and hot water, contributing up to 80% of consumption according to the latest figures from Eurostat.

In a climate change emergency, it is crucial to develop local and affordable low-carbon energy sources with low environmental impact. When electricity gets cleaner, switching to super-efficient ground source heat pumps for heating and cooling can help cut down on using non-renewable energy and lower CO2 emissions.

Infographic on energy consumption in EU householders: 64.4% space heating; 14.5% water heating; 13.6% light and electrical appliances; 6% cooking; 1.1% other uses; 0.5% space cooling. (% share 2021)
Source: Eurostat

However, high capital investment costs and installation time remain significant barriers to uptake. Despite the enormous potential, geothermal energy systems see fewer installations compared with other renewables. Since the 1980s, the development of Energy Geostructures (EGs) has allowed shallow geothermal energy (SGE) to be exploited from structural concrete elements in contact with the ground (e.g., piles foundations, retaining walls, tunnels) by integrating heat exchanger pipes into them.

Energy Geostructures represents a promising innovation in the realm of sustainable energy solutions. These structures integrate ground heat exchange systems within various ground-contact infrastructures, such as retaining walls, piles, tunnels, and other buried structures. By leveraging the stable thermal properties of the earth, EGs offers an efficient means of heating and cooling buildings, reducing energy consumption, and mitigating environmental impact.

One of the key advantages of EGs lies in their ability to tap into the Earth’s natural thermal energy, providing a renewable and low-carbon alternative to conventional heating and cooling systems. By circulating fluid through embedded pipes within the structures, heat exchange with the surrounding ground occurs, allowing for efficient temperature regulation of buildings above.

Despite their considerable potential, EGs face several challenges that hinder their widespread adoption and implementation at a large scale. One of the primary technical challenges involves the design and optimisation of these structures to ensure optimal heat exchange efficiency while maintaining structural integrity. Achieving the right balance between thermal performance and structural stability requires sophisticated engineering and modeling techniques, as well as careful consideration of site-specific conditions and constraints.

Another technical challenge is the integration of EGs with existing building and infrastructure projects. Retrofitting older structures to incorporate these systems can be complex and costly, requiring coordination among various stakeholders and disciplines.

There is a need for understanding among developers, contractors, and policymakers regarding the benefits and feasibility of these systems. Overcoming misconceptions and promoting education and training initiatives are essential for fostering greater acceptance and uptake within the construction industry. The lack of political awareness and promotion activities creates another barrier to strategic investments for EGS at the city scale, calling for a European network.

Introducing FOLIAGE COST Action

To address the identified challenges, the European network for Fostering Large-scale Implementation of Energy Geostructure (FOLIAGE) is a new European network of researchers and engineers, all experts in thermal energy efficiency, geological engineering, and geotechnical engineering. This collaborative network currently gathers 155 researchers, from 32 countries intending to develop collective understanding, share techniques, facilities, and data, and work jointly in disseminating the obtained results across the EU.

Portrait photo of a man

“Foliage is a highly dynamic network in which we bring together stakeholders with different backgrounds and skills to promote the use of Energy Geostructures in civil engineering projects, whether as part of new construction or within the context of retrofitting. We aim to overcome the scientific barriers that hinder the promotion of this technology by acting on the increase of knowledge at different levels: technological issues regarding mechanical and energy design, implementation, and finally the socio-economic issues including financial and life cycle analysis.

Prof. Hussein Mroueh, Chair of FOLIAGE

FOLIAGE COST Action is collecting all needed information to reduce these barriers and foster development by creating a multi-disciplinary network between the different stakeholders (local authorities, communities, developers, designers, academics, contractors, …).

“We are committed to transferring knowledge to young people and innovators who will be the decision-makers and builders of the future. We are implementing these principles and concepts for the benefit of our university community, as part of a full-scale demonstrator, with three main objectives: demonstrate the effectiveness of the technology; stimulate research in geothermal energies, and re-design our pedagogical provisions” adds Prof. Hussein Mroueg.

Energy Geostructures represent a promising track for achieving energy efficiency, sustainability, and resilience in the built environment. By collaborating across disciplines and sectors and investing in research, innovation, and policy support, FOLIAGE COST Action aims to unlock the transformative power of EGs and accelerate the transition to a more sustainable future.

Additional information

View the Action webpage

View the Network website

Eurostat Energy consumption data