We recently showed that ceramic-based electrocaloric regenerators are very interesting for cooling applications [A. Torelló et al., 2020, Science: https://doi.org/10.1126/science.abb8045, J. Li et al., 2023, Science: http://dx.doi.org/10.1126/science.adi5477]. However, the potential of polymer-based electrocaloric regenerators is more than one order of magnitude larger, thanks to a much larger voltage-driven entropy change. This is what we want to investigate in this project, namely polymer-based electrocaloric coolers. 

Hence, thanks to the recent progress made in electrocaloric polymers (ARKEMA Piezotech, France), in electrocaloric heat exchangers (Luxembourg Institute of Science and Technology (LIST), Luxembourg) and in electronic modules for electrocaloric cooling (University of Stuttgart, Germany) , combined with the scale up capabilities of this consortium (KEMET, Italy), the goal of this project is to make an air conditioning system with a high temperature span, a low temperature below room temperature, 1 kW-cooling power and 60 %-efficiency. This requires a multidisciplinary approach combining 1) materials science (development of efficient electrocaloric materials and associated cooling modules), 2) thermodynamics (heat exchange and efficient cycles) and 3) electrical engineering (cooling control and energy recycling to increase efficiency). 

To reach this final goal, three objectives (KO*) have been defined in this project, as sketched in above figure. 

• Key objective 1 (KO1) – Development of electrocaloric polymers-based cooling modules (multilayer capacitors) with a high temperature variation.

• Key objective 2 (KO2) – Fabrication of regenerative heat exchangers with electrocaloric polymer cooling modules reaching a high temperature span and a cooling power density.

• Key objective 3 (KO3) – Reaching high efficiency (coefficient of performance COP relative to the Carnot-limit) by recycling electric energy. 

*More specific and quantitative objectives, approaches and KOs, where already defined project-internally and will be revealed in publications throughout the project duration.

The following information is from https://ec.europa.eu/info/funding-tenders/opportunities/portal/screen/opportunities/topic-details/horizon-eic-2023-pathfinderchallenges-01-01 

Background and scope

Cooling is an essential process across many areas of society, important for human well-being, economic growth, sustainable urbanisation, reduction of food scarcity, and for socio-economic development. It presents relevant applications in sectors such as (i) built environment, heat, ventilation and air conditioning (HVAC), building health and comfort, interoperable urban energy systems, (ii) data centres, electronics and superconductors, (iii) food production (i.e. vertical farming), processing, storage and refrigerated transport, (iv) cold energy carriers production, transport and network integration (liquid H2, LNG, etc.), (v) chemical, metallurgical and hard to abate industries (including cryogenic carbon capture) and (vi) medical applications (e.g. vaccines that need refrigeration).

In terms of cooling technologies, vapour compression is the most widely applied method for air-conditioning and refrigeration. However, a wide range of alternative methods have been developed or are under active development including thermochemical (e.g. sorption) and solid-state (e.g. magnetic, electrochemical, thermo-acoustic, thermo-elastic) based cooling solutions. At the same time, the need for mechanical cooling can be mitigated by using nature-based solutions (such as trees and plants), passive cooling techniques (such as natural ventilation, shades, thermal insulation, radiative cooling etc.), the use of natural energy (e.g. winter cold for summer use, or solar cooling) and behavioural changes or other demand-based technologies.

The demand for cooling is rising and cooling processes often result in significant greenhouse gas (GHG) emissions, due to the use of hydrofluorocarbons (HFCs) or fossil fuel to power cooling equipment. At the same time, the global energy market disruption and increasing costs of energy supply are threating the competitiveness of several high cooling demand sectors, so that the availability of super-efficient and low-cost cold technologies is crucial. These needs call for novel solutions as they cannot be addressed by simply adapting conventional cooling processes and solutions, nor relying on existing supply chains for components and devices. The alternative cooling technologies under development are either for small scale (e.g. solid-state refrigeration) or for a limited temperature range (e.g. sorption based refrigeration).

This Challenge is strategic for the European Green Deal ^[1] and the REPowerEU ^[2] plan, Renewable Energy Directive (RED II), and Energy Efficiency Directive (EED) EU policy objectives, transforming the EU into a resource-efficient and competitive economy, increasing Europe's autonomy on energy and critical materials, preserving Europe’s natural environment, tackling climate change and adaptation to it, food security and health protection, and strengthening the EU technological leadership in this strategic sector.

Overall goal and specific objectives

This EIC Pathfinder Challenge aims at advancing scientific knowledge and technological development of novel, clean and efficient cooling solutions that fully underpin “cold economy” vision.

For this purpose, the portfolio of projects supported under this Challenge should explore the potentials of new devices, processes, components and materials for clean cooling generation, storage and/or transport, such as:

• Generation of clean cooling which may integrate the use of renewable energy, waste heat/ cold harvesting, passive and radiative cooling, thermochemical and hybrid heat pumps, heat transformers, waste heat recovery, heat pipes); solutions for a wide range of applications ranging from vaccine storage temperature (-80 to 4°C), food (-40 to 12°C), data centres and air-conditioning (6 – 12°C) are eligible;
• Store and/or transport of cooling (spatially and/or temporally decoupling demand and generation), clean cold chain transportation, thermal energy carriers, inter-seasonal storage, including charging/discharging dynamics where relevant (i.e. short charging times and mid to long duration storage);
• Utilization and/or management of cooling, such as cascade use of cold energy for different temperature requirements, integration of innovative and low/ net zero cooling concepts in critical demand segments (i.e. data-centre, hard-to-abate industrial sectors, buildings, specific solutions for food processing or medical applications) or other demand side related technologies).

Specific objectives of the Challenge are to explore new devices, processes, components and materials for cooling. Technologies to be integrated in products and services shall demonstrate their potential to (i) reduce investment/operational costs, (ii) increase efficiency, operational reliability and interoperability, (iii) avoid the use of critical raw materials ^[3] or harmful refrigerants and (iv) pursue circularity by design approaches, low environmental impact and low carbon footprint.

The proposals should refer the expected COP (coefficient of performance) to the max theoretical COP of the inverse Carnot cycle and describe how the proposed solution can be competitive with the state of art at the proposed operating range. The proposed solutions should aim to achieve single stage temperature gradients higher than 5 °C at a competitive COP.

The proposals submitted in response to this Challenge may address fields such as:

• unconventional refrigeration technologies and systems including but not limited to functionalised Phase Change Materials (PCM), thermochemical materials, thermophotonic, elastomeric, barocaloric, magnetocaloric or thermally regenerative electrochemical cycles; new compression-expander mechanisms (i.e. electrochemical compression), use of mixed refrigerants or other novel cycles configurations;
• computational modelling and validation of energy-intensive low-temperature heat transfer processes, materials and components including their design, manufacturing, optimisation and dynamic performance (i.e. novel heat exchangers, compressors etc.);
• ultra-energy efficient operations and logistics along the cooling supply chain and final use, decoupling supply and demand via thermal carriers (PCMs, thermochemical materials, ice slurries, liquid air, molecular storage etc.) or systems integration, including mobile cold energy storage and associated charging solutions; interoperability of district networks, reversible heating and cooling infrastructures, or cold-to-power solutions;
• new designs and concepts for food processing and medical applications; unconventional refrigeration principles (such as thermoelectric, magnetocaloric, electrocaloric, elastomeric or barocaloric, photonic cooling conversion) or new compression-expander mechanisms (scroll, electrochemical compression), mixed refrigerants, novel cycles configurations.

The proposals may include smart interoperability solutions for electricity, heating and cooling networks integration, including reversible heating and cooling infrastructures, or cold-to-power solutions with waste heat and cold energy streams recovery from industrial processes, data centres and/or air conditioning of buildings.

Expected outcomes and impacts

The supported projects shall individually provide proof of concepts for unconventional approaches (at materials, component, process or device level) that can convincingly impact the energy consumption, emission reduction and cost reduction of the cooling sector. The portfolio of supported projects should contribute to one or more of the following medium to long-term impacts:

• Increase the EU technological leadership in the cooling sector and in strategic productive fields strongly linked to cold production (such as food),
• Improve building comfort and health in living environment,
• Increase operational security of server and computing facilities,
• Reduce carbon footprint of energy systems and address climate change mitigation,
• Address climate change adaptation (in particular in semi-desert areas) and food security, including possibilities of international outreach,
• Reduce EU dependency from, and diversify EU sourcing of, critical materials supply.

For more details, see the EIC Work Programme 2023.

[1]A European Green Deal | European Commission (europa.eu)

[2]REPowerEU: affordable, secure and sustainable energy for Europe | European Commission (europa.eu)

[3]Critical raw materials (europa.eu)