Decentralised Hydrogen Fuelled Gas Engine CHP Units: A Feasibility Study with Modelica

Abstract

The use of hydrogen gas as an alternative fuel to power energy systems has been a topic of research over the last few decades and is currently gaining importance, even more due to current circumstances related to decarbonising energy supply. One focus of research is the use of hydrogen gas in combined heat and power gas engines, as this type of energy conversion is known for its high efficiency. For this reason, a cross-border project between France and Germany is developing a living laboratory in the Upper Rhine region to investigate the feasibility of hydrogen gas as an alternative fuel in a holistic decentralised energy system. It consists of several energy components, including a polymer electrolyte membrane electrolyser (PEMEC), gas engine combined heat and power (CHP) unit, photovoltaic (PV) panels, hydrogen storage, thermal and electrical energy storage. To enable and demonstrate multiple what-if scenarios of possible variations of the energy system, a simulation model was developed using Modelica. Users, e.g. local authorities, landlords, businessmen, etc., of this simulation model could utilize it as a decision support tool for designing a carbon-neutral energy system for their own use. This paper describes the development of the model and its application with real measured data from municipal buildings in the city of Offenburg, Germany. The results indicate that the suitability of the model and the use of hydrogen CHPs can be beneficial for this specific use case.