UC wants to boost home energy efficiency with materials that act as “thermal batteries”

The Faculty of Sciences and Technology of the University of Coimbra (FCTUC) is coordinating the international project Optimising Energy Efficiency with PCM Integration in Portuguese Residences (3D-EE-Struct), which aims to enhance the energy efficiency of Portuguese homes by integrating phase-change materials (PCMs) into building materials, including walls, ceilings and floors.

Ajitanshu Vedrtnam, a researcher at the Association for the Development of Industrial Aerodynamics (ADAI) at FCTUC, explains that these materials act as ‘thermal batteries’, naturally regulating indoor temperatures by storing heat during the day and releasing it when needed. This reduces the reliance on traditional heating and cooling systems.

“The 3D-EE-Struct project focuses specifically on lightweight building structures, which are ideal for the Portuguese climate. The main goals are to reduce household energy consumption and greenhouse gas emissions, to develop practical and proven strategies for incorporating PCMs into both new buildings and renovations, and to optimise the type and placement of PCMs through advanced computational modelling and laboratory testing," Vedrtnam notes.

The research team also aims to provide solutions that improve indoor thermal comfort while significantly reducing energy costs.

"We anticipate potential energy savings of up to 25% in heating and cooling requirements for small dwellings, with automatic indoor temperature adjustments of up to 5–8 °C in summer and winter. We also plan to develop practical and clear guidelines for architects, builders, and policymakers interested in implementing PCM-based energy solutions,” says Nelson Soares, professor at the Department of Mechanical Engineering at FCTUC and researcher at ADAI.

The team's plans include validating simulation models in a real flat in Coimbra, facilitating accessible, climate-adapted housing solutions, and reducing reliance on mechanical heating and cooling systems. Additionally, the researchers will develop new scientific tools and structural solutions to support future research and commercially viable applications in the field of sustainable construction.

Coordinated by the University of Coimbra, the project brings together experts from Portugal, the United States, Slovakia and India. It has been awarded a grant of approximately €173,000 under the Marie Skłodowska-Curie Postdoctoral Fellowships scheme, managed by the European Research Executive Agency (REA) as part of the Horizon Europe programme.