Hydrogen-powered engines
There are two technologies: hydrogen fuel cell electric vehicles (FCEVs) and hydrogen internal combustion engines (H2ICE). FCEVs generate electricity from hydrogen in a device known as a fuel cell that is used to power the electric motor, whereas H2ICE burn hydrogen in an internal combustion engine.
While most discussions around hydrogen are centered on efficiency gains achievable using fuel cells, there has been a renewed interest in H2ICE lately. Powertrain development companies are developing H2ICE for heavy-duty applications, with a focus on increasing the efficiency potential of multiport and directly injected hydrogen concepts, utilizing the existing powertrain architecture. For instance, a multinational engine manufacturing and fuel technology company recently developed a H2ICE engine for heavy-duty trucks across the 10 to 26 ton GVW (gross vehicle weight) range. A major construction equipment manufacturer has invested 100 million pounds to produce super-efficient hydrogen engines, rolling out its 50th H2ICE in January 2023.
Most of these OEMs are modifying their existing conventional spark-ignition engines to develop H2ICEs. This is because a four-stroke H2ICE operates on the same cycle as a regular natural gas engine and shares most of the components. H2ICE, however, requires minimum changes to the fuel injection and ignition systems, along with different controls, to handle high pressure hydrogen fuel and the corresponding light changes to the cylinder head.
With higher part-sharing and a known technical arena, R&D costs required to develop H2ICE from a base spark-ignition engine are much lower than the cost of FCEV development. Also, with these engines being manufactured in the same production facilities and following the same manufacturing processes as conventional fossil-fuel ICE, with limited changes, economies of scale could be achieved faster. Moreover, the existing and established ICE supply chain can be leveraged efficiently.
An area where additional investment would be needed is that H2ICE requires a storage tank similar to FCEVs. In comparison to H2ICE, fuel cell technology is very cost-intensive. Operationally, it requires pure hydrogen and a high specification compressor to supply compressed air. Intricate designs of critical components such as bipolar plates, membranes, etc., add to the cost. Also, new development and testing methods are required to validate the technology.