Energy: Novel fuel cells produce electricity and heat using gas and hydrogen mix

Developing an innovative cogeneration system with fuel cells capable of operating with mixed hydrogen to produce "carbon free" electricity and heat, promoting diffusion of renewable energy and reducing greenhouse gas emissions, is the objective of the project SO-FREE coordinated by ENEA and including eight other partners from industries and research institutions. The goal is to create a new generation of solid oxide fuel cells capable of operating with different mixtures of combustible gases (biogas and mixtures of natural gas and hydrogen) for an efficient, zero emission, flexible electricity and heat production. A cogeneration system designed for end users in the residential, commercial and agricultural sectors.

 “Modern commercial SOFC-microCHP fuel cell systems, mainly employ natural gas. However, to encourage greater production and use of clean energy while taking advantage of existing infrastructure for natural gas distribution, it is essential to be able to use blends of natural gas from renewable sources, like green hydrogen and biogas,” explained Viviana Cigolotti, head of the ENEA Laboratory for Energy Storage, Batteries and Technologies for the Production and Use of Hydrogen. “With this project – she said – we intend to contribute to one of the most promising technologies for electricity production and heat cogeneration, developing two SOFC-CHP systems based on fuel cell modules from two different manufacturers and making them interchangeable” .

The new systems will be tested in a residential context, specifically in an experimental housing unit at the headquarters of one of the project partners (IEN - Institute of Power Engineering), to evaluate their operation, the production of electricity and heat with different gas mixtures.

Funded as part of the Horizon 2020 Program of the European Commission^[1], SO-FREE is divided into several phases: study of the effects of different fuels on solid oxide systems operation at various operating temperatures; optimization of exhaust gas recirculation; development of two innovative 5 kWe systems suitable for working with different fuels; creation of a communication system between the two different modules in order to make them interchangeable, which will be presented to the International Electrotechnical Commission (IEC) for its standardization; tests conducted in real residential conditions to demonstrate a 40% reduction in CO2 emissions with renewable gas mixtures compared to the same systems powered entirely by natural gas.

The new systems will be tested in a residential context, specifically in an experimental housing unit at the headquarters of one of the project partners (IEN - Institute of Power Engineering), to evaluate their operation, the production of electricity and heat in operation of the different gas mixtures used.

ENEA is involved together with its partner IEN in the characterization of the short-stacks supplied by the ELC (Elcogen Oy) and IKTS (Fraunhofer-Institut für Keramische Technologien und Systeme) industries in the study and validation of their performances, using various compositions (natural gas, hydrogen and blending mixtures) in the conditions envisaged by the project. Furthermore, ENEA will be involved in the management of the dissemination plan, in the valorisation of the know-how and the technology developed and in the development of the NWIP (New Work Item Proposal) to be presented to the International Electrotechnical Commission (IEC) for the standardization of the stack interface -system in the international regulatory field.

The partners involved in the project will conduct in parallel an analysis on market opportunities of cogeneration systems in various European countries, taking into account their specific characteristics (climate and infrastructure), regulatory aspects and incentive mechanisms.