The world’s largest PEM hydrogen electrolysis plant is situated on the premises of Shell Rheinland’s refinery in Wesseling. Since July 2021, it has been covering part of its hydrogen requirements via green hydrogen based on electricity from renewable energy sources. A European consortium consisting of Shell, ITM Power, SINTEF, thinkstep, and Element Energy uses the REFHYNE project to not only to reduce the site’s CO2 emissions but also contributes to the energy transition in the refinery industry.

The Shell Rheinland refinery at the Wesseling site, which is Germany’s largest refinery, requires some 180,000 tonnes of hydrogen each year for fuel production. Around 70 to 80 per cent of its overall requirements are produced as a by-product of the refinery’s processes. Before the construction of the plant the company produced the remaining 20 to 30 per cent from natural gas via steam reforming. Now the REFHYNE plant takes over a small part of the hydrogen production in future and reduces CO2 emissions at the site by utilising renewable energies.

Innovation: first large-scale industrial PEM application

Shell joined forces with ITM Power, SINTEF, thinkstep, and Element Energy to implement the project, which is funded by the EU’s Fuel Cell and Hydrogen Joint Undertaking (FCHJU). The plant’s key element consists of a ‘PEM’ electrolyser made by ITM Power. ‘Polymer electrolyte membrane’ or ‘proton exchange membrane’ electrolysers offer excellent performance and can be adjusted almost instantaneously. This makes them particularly suitable for use with fluctuating electricity supplies in order to stabilise the grid in the context of network balancing. The project is the first time the PEM technology has been applied on a large industrial scale in a refinery.

‘REFHYNE is a flagship project for Europe and for Germany’s energy transition, as this is the first time the world’s largest 10-MW PEM water electrolysis plant has been fully integrated and operated in a refinery as a platform for sector coupling,’

Dr. Frithjof Kublik,

Efficiency: using experiences from REFHYNE for a 100-MW design

Based on its capacity of ten megawatts, the plant is capable of producing around 1,300 tonnes of green hydrogen each year. This initially corresponds to around one per cent of the hydrogen required by the refinery. However, the modular structure of the electrolysis system allows the electrolyser to be expanded on a step-by-step basis, which means up to ten per cent of the site’s requirements can be met by green hydrogen in future. As a result, ITM Power wants to build on the experiences gained with the 10-MW plant during the REFHYNE project to develop a design for a 100-MW plant. The high-purity hydrogen the plant produces is intended to be used primarily for processing the refinery’s products. A further conceivable application is using the hydrogen in the transport sector. For example, those behind the project are planning to offer the hydrogen for refuelling vehicles with fuel cells at the Shell filling station in Wesseling.

Impact: sustainable reduction of CO2 emissions

By building a PEM electrolysis plant, Shell is making it possible to integrate renewable energies in the refinery process. This approach not only reduces CO2 emissions directly but also improves the market conditions for electricity from renewable energy sources in this energy-intensive industry. Energy companies like Shell are among the largest industrial users of hydrogen. Producing hydrogen using steam reforming, which is currently the foremost method in large-scale industry, generates large quantities of CO2, with around ten tonnes of CO2 being emitted per tonne of hydrogen. So there is a great potential to make savings by gradually shifting production to electrolysis with electricity from renewable energy sources.