Hydrogen vehicles:
cleaner mobility


Hydrogen-powered internal combustion engines promise two things: to put cleaner automobiles on to our roads, and to launch Europe as a world leader in the hydrogen-based economy of the future. At the forefront of this drive appears a European research project HyICE, coordinated by the BMW Group and bringing together 11 partners from 4 EU Member States.

The project has made huge leaps towards these goals through the optimisation of hydrogen-powered internal combustion engines. The team made spectacular improvements to energy efficiency and engine power, and developed the components needed to make hydrogen-powered vehicles a reality. Furthermore, a hydrogenadapted calculation tool for series development has been made commercially available.

This was the first time that a research project was able to concentrate exclusively on the hydrogen combustion engine and thus the specific properties of hydrogen. Previous engine designs were intended for both petrol and hydrogen due to a lack of hydrogen-equipped filling stations. But facilities are now being put in place in Scandinavia, Germany, Japan and North America for hydrogen-only vehicles.


A simple gas – not a simple issue

The aim of HyICE was to develop an internal combustion engine utilising hydrogen fuel. The new engines should be as efficient as diesel engines but without the pollution, and with as little trade-off as possible between engine size and power.

By use of the well-established internal combustion engine, the chemically bound energy of hydrogen can be converted directly into mechanical propulsion energy. Europe’s competitiveness is linked to its ability to transport goods across and between countries efficiently and inexpensively. The environmental costs of transport are also of increasing importance, and another reason for research projects such as HyICE: hydrogen fuel generates practically zero emissions.

At its core, HyICE is about hydrogen fuel, but its peripheral influence is significantly larger than this. The technology discovered within the project could be shared, built upon and utilised in industries requiring stationary power generation in the near future.

The motivation behind developing hydrogen-based internal combustion engines revolves around these factors, and is additionally driven by the desire to free the EU of dependency on limited resources of fossil fuels. Furthermore, stringent EU environmental laws have pushed researchers and developers to investigate alternative fuels. Hydrogen constitutes the only carbon-free energy vector that glimmers with potential for the solutions needed.

The HyICE effect: more powerful than a standard modern engine

HyICE is structured around multiple sub-projects. For example, the project investigated two approaches for mixture formation – direct hydrogen injection and the injection of deep-frozen hydrogen into the inlet port of the engine. In this case the injection takes place at very low pressures at the same conditions as the hydrogen is stored in the fuel tank of the vehicle. Both approaches were found to be equally effective, producing a 25 % increase in power output. At the same time, sub-projects developed new hydrogen injectors fitting to the specific principles of mixture formation. To support the development process of future series hydrogen engines, Computational Fluid Dynamic modules have been adapted and validated by experiments. These proven modules have then been integrated into a commercial solver now available for any engine manufacturer.

A major success was an enormous improvement in energy efficiency by the hydrogen engine and a power density of 100 kW/litre displacement, which equates to a horsepower of around 136. This by far exceeds the level of the average modern car diesel engine, which is around 77kW/litre or 105 horsepower.

Engine-driven coordination

HyICE used expertise from across the globe. The team shared its findings on a regular basis with researchers from the US Department of Energy laboratories, as well as universities in the US. The EU and US have strong links in the area already, dating back to a 2001 agreement on cooperation in hydrogen and fuel cells research. The impact of HyICE will be seen far beyond Europe’s borders, and while Europe is leading the way in innovative combustion engines, it is also ahead of the competition in hydrogen research in general. The EU has proposed a Joint Technology Initiative (JTI) on hydrogen and fuel cells, which receives EU funding and is driven by European industry.

A bridge to a hydrogen future

Today’s gasoline and diesel engines represent economic energy converters. The production costs of monofuel hydrogen engines designed in line with the outcomes of HyICE will roughly be the same. The results of HyICE prove that hydrogen engines have the capability to surpass the efficiency of diesel-based technology and remain nonpolluting.

In combination with an optimised energy management of the vehicle a consumption of 1 kg hydrogen/100 km, representing 3,7 l gasoline fuel should be achievable with a passenger car. All that is missing now is the infrastructure that must be in place to get these engines in vehicles and on the road. The next step will therefore be a deeper investigation of two major areas in this respect: hydrogen production, storage and supply. As always, laboratory research needs practical application so that it is tested and assessed. This is taking place in other EU-funded projects, such as HyFLEET: CUTE, which is putting 47 hydrogen buses in 10 major cities, from Amsterdam and Barcelona to Beijing, Reykjavik and Perth. They are operating under real-life conditions.

HyICE is not only conducting fundamental research and development in components vital for hydrogen-based engines, such as lubrication, piston rings and liners. It also heralds a promising future by offering an economic solution for the creation of hydrogen-based transport and a hydrogen-based economy.