ULEMCo and its R&D partner Revolve Technologies have demonstrated thermal efficiencies of 45% in engine control strategies for a 100% hydrogen-fueled engine being developed for the Mega Low Emissions (MLE) truck demonstrator unveiled earlier this year. (Earlier post.)
The 100% hydrogen engine runs stably at air/fuel ratios in excess of 300:1.
This milestone performance shows that it is possible to go well beyond previously reported energy efficiency results for hydrogen combustion, at the same time as achieving immeasurable NOx levels, according to ULEMCo. The company says that the results point to the realistic prospect of zero emission trucks running on 100% hydrogen in the relatively short term.
ULEMCO’s approach of adapting existing diesel engine designs to run on hydrogen-diesel dual fuel has provided substantial learning on the opportunity for zero-emission engines. This ultimately provides routes to the much quicker adoption of hydrogen in heavy duty applications than alternative approaches, which are still many years away from cost effective commercial availability, the company suggests.
A recent report from the Department for Business, Energy and Industrial Strategy (BEIS)-sponsored Committee on Climate Change (CCC) on the future role of hydrogen in a low carbon economy referred to hydrogen in vehicles as potentially playing an important role for heavy-duty vehicles (e.g. buses, trains and lorries).
Similar conclusions were reached for longer-range journeys in lighter vehicles, where the need to store and carry large amounts of energy is greater.
The report acknowledges that although overall well-to-wheel efficiencies are less for hydrogen than for battery EV, the latter’s negative impact on payload means that according to the report he aim should therefore be to move HGVs to zero-carbon energy (i.e. electricity and/or hydrogen) where feasible by 2050.
As a hydrogen vehicle can be refueled quickly, fleet operators can also plan for similar numbers of vehicles to their current operation, rather than needing to increase fleet size to cover lengthy charging times for EVs.
These excellent results represent engine efficiency levels very similar to those seen with some fuel cell technologies. Combining these results with our knowledge of how to ensure that the engine can operate over a wide performance curve—and with industrial grade hydrogen—gives us confidence in this approach. Vehicle operators, particularly in heavy duty applications, will have a truly cost effective option for very low carbon and zero emission driving in the future.—Amanda Lyne, Managing Director at ULEMCo