The hydrogen and
fuel cell center
ZBT GmbH

HiPowAR - Highly efficient Power Production by green Ammonia total Oxidation in a Membrane Reactor

Within the EU project HiPowAR ZBT will be responsible for the assesment of the economic feasibility and competitiveness and the environmental impact of the developed technology compared to the use of ammonia in solid oxid fuel cells (SOFC) and internal combustion engins (ICE) by means of LCC/LCOE and LCA methodologies.

Partner: INP Greifswald, ZBT GmbH, POLIMI, Fraunhofer IKTS, PBS, RANOTOR

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 951880.

Renewable ammonia is considered increasingly as a carbon-free green fuel opening up the path to a new nitrogen-based energy economy. Its energy density by volume is nearly twofold compared to hydrogen with easier shipping, storage and distribution. As the market grows due to efforts of various companies (e.g. YARA) into greening the production process, the distribution routes for importing ammonia and ammonia fueling technologies will follow suit. The project shall promote the acceptance of ammonia as a synthetic fuel without CO2 emissions. It focuses on a breakthrough in the direct energy conversion from NH3 fuel to power.

For that purpose, a new promising process based on a membrane reactor will be realized and characterized experimentally. The process is comparable to a fuel cell with an inner short circuit but without any typical electrical interconnections avoiding electrical losses. Therefore, the system is much simpler and less expensive than a SOFC (Solid oxide fuel cell). The chemical energy of liquid ammonia is converted into a highly compressed gas (N2 + H2O) through a so-called self-pressurizing combustion in a pressure vessel with constant volume. The power is collected by the work of expansion using a gas expander, e.g. in a gas expander like a steam turbine or engine. Since high pressure enhances the total process efficiency, membrane reactor consists of tubular ceramic membranes able to withstand very high outside gas pressure. The membranes are conductive for oxide ions and electronic charge carriers and realize the inner electrical short circuit in a single element. They are also called MIEC (Mixed Ionic Electronic Conductor), ITM (Ion transporting Membranes), OTM (Oxygen transporting Membranes). Comparable to the fuel cell, thermodynamic efficiency of the process is not restricted. In contrast to internal combustion engines, steam power plants or other processes based on cycling of a working fluid, a much higher efficiency is expected.