CNRS-PROMES: innovation for TCM energy storage

CNRS-PROMES: innovation for TCM energy storage

The National Centre for Scientific Research (CNRS) is the largest public research organisation in France, accounting for around 1 100 services and/or research units throughout the country. With more than 32 000 people (researchers, engineers, technicians and administrative staff), a 2009 budget of 3.367 billion euros, an implementation on all national territory, the CNRS is an active multidisciplinary institution that covers all fields of scientific research driving various programs and actions designed to address society and industry expectations. CNRS conducts research in all scientific, technological and societal like mathematics, physics, communications, nuclear physics, chemistry, social sciences, environmental sciences or engineering. The CNRS administration at the local level relies on its 18 Regional Delegations. 


The research unit CNRS-PROMES (UPR8521 – Laboratory for PROcesses, Materials and Solar Energy) involved in MiniStor project is a key laboratory belonging to the Institute for Engineering and Systems Sciences (INSIS) of the CNRS and is closely associated to the University of Perpignan. CNRS-PROMES is located in three close sites: Odeillo-Font Romeu (1 MW CNRS Solar furnace), Targassonne (5 MW Themis solar tower) and Perpignan (Tecnosud).


Odeillo-Font Romeu CNRS Solar furnace Targassonne Themis solar tower Perpignan_Tecnosud

PROMES laboratory: (from left to right) Odeillo-Font Romeu / Targassonne / Perpignan


CNRS – PROMES has been involved in solar energy for more than 50 years. Its mission is the development of science and technology using unique properties of concentrated solar energy to enhance and create new applications of this renewable energy resource. PROMES is the leader of the laboratory of excellence SOLSTICE (Solar Energy: Science, Technology and Innovation for Energy Conversion). CNRS-PROMES laboratory have a long experience in the coordination of European and national collaborative research projects in energy conversion/storage fields. For the five past years, CNRS-PROMES is involved in 26 collaborative projects and manages 8 of them.


The scientific and technical staff of PROMES is about 150 persons including PhD students. The main research activities of the laboratory are related to the efficient energy conversion using innovative thermodynamic and thermochemical processes, the improvement of high temperature materials, and the development of low environmental impact processes. High priority scientific topics focus to solar power generation using thermodynamic cycles, hydrogen production, medium and high temperature heat storage, high energy density thermal storage, high temperature materials characterization, materials synthesis, solar heating and cooling of buildings,..


Contribution of CNRS-PROMES  in the MiniStor Project

The EU-funded MiniStor (Minimal Size Thermal and Electrical Energy Storage System for In-Situ Residential Installation) project aims at developing an advanced compact and integrated thermal storage system. One of the storage unit that is developed into MiniStor system is a thermochemical process (TCM) enabling to high energy storage capacity (200-250 kWh/m3 of material). Such a thermochemical system implements a reversible reaction between ammonia and calcium chloride.  CNRS-PROMES play a leading role in the design optimization and implementation of TCM storage units:


  • Optimize the salt/graphite reactive material that is implemented in such thermochemical storage with the aim to achieve high energy and power density under variable thermal energy input/output. 

  • Dimensioning and design optimizisation of the TCM thermochemical reactor. 

  • Definition of the design specifications and sizing of the different components and ancillary equipments (evaporator, condenser, compressor, valves,…) of the TCM storage unit.

  • Realisation of preliminary performance tests of the TCM unit, in controlled operating conditions before their installation in demonstration sites.

  • Safety assessment and risk management linked to the use of ammonia in TCM storage unit: procedure for a safe handling of ammonia, first ammonia charging in the TCM unit, prevention of leakage, implementation of specific measurement and control instrumentation…