EFC2023 Conference – CNR-ITAE
Abstract
The direct production of highly pressurised hydrogen from electrolytic water splitting can save relevant amounts of energy compared to down-stream gas compression. The aim of ADVANCEPEM is to develop a novel polymer electrolyte membrane (PEM) electrolyser which can produce hydrogen at very high pressures (200 bar) thus reducing the energy consumption required for post-compression. Very pure and high-pressure electrolytic hydrogen can be directly used in various industrial processes such as ammonia synthesis requiring up to 200-300 bar, hydrogenation of oils and other hydrogenation processes in refineries requiring feed pressures up to 200-250 bar, methanol synthesis requiring 70 bar etc. and for direct injection into the high-pressure gas grid (∼ 80 bar).
Another key goal is development of a cost-effective technology enabling large-scale application of PEM electrolysers. A significant reduction of capital costs will be achieved by minimising critical raw materials, developing low-cost coated bipolar plates, operation of the electrolyser at a high production rate while maintaining high efficiency (about 80% vs. HHV) and safe operation. ADVANCEPEM aims to develop a set of breakthrough solutions at materials, stack and system levels to increase hydrogen pressure to 200 bar and current density to 5 A/cm2 for the base load, while keeping the nominal energy consumption <50 kWh/kg H2. Reinforced Aquivion® polymer membranes with enhanced conductivity, high glass transition temperature and increased crystallinity, able to withstand high differential pressures, will be developed for this application. This innovative membrane will be operated at high temperature 90-140 °C under high pressure to provide for increased energy efficiency. To mitigate hydrogen permeation to the anode and related safety issues, efficient recombination catalysts will be integrated into both membrane and anode structure.
The new technology will be validated by demonstrating a high-pressure electrolyser of 50 kW nominal capacity with a production rate of about 24 kg H2/day in an industrial environment. The project will also deliver a techno-economic analysis to assess reduction of the electrolyser CAPEX and OPEX. The consortium comprises an electrolyser manufacturer, membrane and catalyst supplier, a membrane electrode assembly (MEA) developer and an end-user for demonstrating the system.