Next-generation Bi-fuel Diesel-Hydrogen Propulsion in Commercial Vehicles – Revolve’s ground-breaking H2ICED™ builds on the successful H2ICE project in latest-generation Transit

This demonstrator carries on from Revolve’s advanced H2ICE petrol transit by modifying the engine of the latest Euro5 Ford Transit’s 2.2l Puma Diesel vehicle to operate using compressed hydrogen gas as the main fuel, with minute quantities of diesel as the ignition catalyst. The vehicle seamlessly operates in fully diesel-only mode or as a unique bi-fuel diesel-hydrogen engine, without any adverse effects.

The specially built demonstration vehicle is the first in a fleet of similar vehicles about to be produced to promote eco-friendly green vehicles designed to show that hydrogen as a fuel – and the associated equipment – is practical and efficient in a vehicle powered by an internal combustion engine. The concept is expected to accelerate the availability of ultra-low CO2, hydrogen-fuelled commercial vehicles operating in Britain.

The conversion features Ford’s 2.2-litre 4-cylinder Puma diesel engine, to which we have added hydrogen injection and separate ECU control system. This provides hydrogen into the engine which is then ignited in a carefully controlled manner using the right quantity of diesel injected at the right time. The engine retains its conventional diesel injection and ECU control system which allows it to maintain its full diesel range.

The higher compression of the diesel engine (over the previous-generation petrol units) improves thermodynamic efficiency, with the engine’s existing turbocharger providing the optimum low speed boost, and running the system throttle-less is ideally suited to hydrogen’s wide combustibility range (like diesel itself) allowing the engine to achieve in excess of 40% thermodynamic efficiency during its extensive dyno development phase.

At higher loads, the engine utilises larger quantities of diesel injection with the hydrogen to achieve the same torque curve as the diesel-only engine, meaning no performance degradation at all. The hydrogen naturally promotes incredibly clean combustion with particulate masses being in excess of a factor of 10 lower than diesel-only.

Uniquely, the use of EGR while running on hydrogen allows the NOx emissions to match or better the NOx of the base diesel calibration at part load which itself is using high percentages of EGR.

The hydrogen fuel is currently designed to be stored in two large tanks, under-slung below the vehicle floor. This installation provides a usable storage capacity for up to 3.2 kilograms of hydrogen at 350bar (5000psi) and gives an estimated range between 95 miles for the urban cycle and 135-plus miles for open highway running. Utilising the maximum energy from hydrogen, the engine consumes a miserly five litres of diesel at the same time which gives in excess of 100mpg diesel consumption.

Additional hydrogen capacity can be added if required, extending the range further. Importantly, the location and configuration of the tanks allows the retention of the volume and load height of the base vehicle – with absolutely no intrusion or interference within the load space.

For more information, please contact Alec Pell-Johnson at Revolve on +44 (0) 1277 261400 or email Please quote Reference H2ICED™