Efforts to establish a robust hydrogen-based transport sector in Europe must be underpinned by an equally healthy manufacturing industry for essential hydrogen-powered vehicle components.
While Europe has lagged behind Asia and North America in developing hydrogen fuel cells for automotive applications, several initiatives by leading vehicle manufacturers, parts-makers and research institutes are helping European industry catch up and build the know-how, technology and capacity to compete effectively.
The vast majority of hydrogen fuel cell vehicles on Europe’s roads today, from public buses to a small but increasing number of private cars, rely on fuel cell stacks from companies in Japan, Canada and the United States. The fuel cell stack contains the key components – bipolar electrically-conductive plates and membrane electrode assemblies – that enable the electrochemical process of turning hydrogen and oxygen into electricity to power the drive train. Fuel cell stacks are therefore the heart of all hydrogen-powered vehicles and, by extension, of a sustainable, efficient and pollution-free transport sector.
“Industrial fuel cell development in Europe has lacked both state-of-the-art stack products and competitive stack suppliers for automotive applications. Only a few European suppliers can deliver mature components with the requested specifications, resulting in European vehicle manufacturers using components from abroad, particularly Japan and Canada,” explains Ludwig Jörissen, head of the Fuel Cell Fundamentals department at German research institute ZSW.
That situation is gradually changing, however, not least due to a series of projects in recent years funded through the Fuel Cells and Hydrogen Joint Undertaking (FCH JU), a European public-private partnership supporting research and demonstration activities in the sector.
Beginning with AUTO-STACK in 2009 (which laid the foundations for a European fuel cell stack industry) through to STACKTEST (which established testing specifications and standards for the sector) and the ongoing AUTO-STACK Core, the initiatives have brought together key stakeholders, especially small and medium-sized enterprises, in a collaborative effort to make state-of-the-art fuel cell stack production commercially viable in Europe.
Jörissen, the coordinator of all three projects, says the efforts are contributing to a significant evolution in the industry that is reflected by strong improvements in component and stack properties. This is enabling the commercial production of fuel cell stacks from European suppliers that are able to meet durability, efficiency, power density and cost requirements.
A platform to build economies of scale
The most recent initiative, AUTO-STACK Core, which builds on the predecessor projects, establishes a platform concept to substantially improve economies of scale and reduce critical investment costs for individual manufacturers. By sharing the same stack technology and hardware for different vehicles and vehicle categories, the approach addresses some of the most critical research, development and cost-efficiency challenges of fuel cell stack manufacturing and commercialisation.
Involving three vehicle manufacturers, three system integrators and three component manufacturers as well as five research institutes, the project has so far developed a fuel cell stack able to generate 95 kilowatts (kW) with a weight of just 47 kg and a volume of 35 litres, providing a market-competitive power density of 2.8kW/l. In a second version, currently undergoing testing, the stack weight has been reduced to 33.4 kg and the volume to 29.3 litres while stack power has been maintained.
The fuel cells use polymer electrolyte membrane (PEM) technology, the current standard for hydrogen-powered automotive applications due to its comparatively high power density and low operating temperatures and pressures. Though cost remains a challenge, largely due to the use of platinum in the membrane as the catalyst for the electrochemical reactions, it is an issue that all manufacturers face globally and will only be solved by the discovery of a revolutionary alternative, Jörissen points out.
“In AUTO-STACK Core we carried out extensive cost engineering to ensure that the stacks we are developing are cost-competitive. This can largely be achieved with design-to-cost methodologies and through building economies of scale. At just a few tens of thousands of units per year – quite a small number in the automotive industry – manufacturing these components using our approach would be commercially viable,” Jörissen says.
The project is targeting stacks that can be priced competitively at under €40 per kilowatt, a price that is only likely to be achieved through sharing the initial costs of developing a common stack hardware platform. This will enable manufacturers to establish economies of scale in the beginning of the commercialisation phase, when individual volumes are still low.
“Manufacturers can of course develop fuel cell stacks independently but they would be repeating the development processes and multiplying the costs across the industry,” Jörissen notes. “What we are saying is that it is better to develop the underlying platform together and then manufacturers can go on to differentiate their specific designs when the market is more mature.”
A similar need for the industry to work together was reflected in the STACKTEST project, which developed and validated industry-wide harmonised test procedures for fuel cell stacks focused on performance, durability and safety. The initiative has made a significant contribution to the development of international standards, particularly International Electrochemical Commission standards on the testing of automotive fuel cells.
All of these developments point to the increasing maturity of the sector and the functional readiness of hydrogen fuel cells in automotive applications, although considerable scope remains for performance and efficiency improvements through future research and development.
As environmental awareness increases and more stringent emissions regulations come into effect, hydrogen-powered vehicles are already becoming a growing presence on Europe’s roads. Within a few years, the fuel cell stacks that turn hydrogen into clean, efficient electrical power onboard the vehicles may be produced commercially in Europe as well.