It is widely accepted that one of the most challenging transport sectors to decarbonise is the heavy-duty and off-highway sector.
With traditional long haul and off-highway vehicles being reliant on the energy dense qualities of diesel for decades, it has become necessary for these sectors to move away from their reliance on fossil fuels and find alternative ways to decarbonise.
We have previously looked at the possibilities of some developers still insisting that electrifying all sectors of the transport system is the only way forward. However, it is also wildly accepted that heavy duty vehicles which depend on being active often twenty-four hours a day, cannot rely on an electrification model to give them the longevity and energy density required to function.
Off-highway vehicles are also often in use twenty-four hours a day and are often running in remote areas, often running in high temperatures and where there is a lot of dust. They also require a fuelling system which will allow them to be running day and night with only a short window of opportunity for refuelling. Furthermore, as off-highway vehicles do not move fast, keeping their engines and systems cool poses additional problems.
Fleet owners are keenly aware that they need to source alternative fuels for their heavy-duty or off-highway vehicles.
However, the cost of replacing entire fleets for some companies would be unfeasible. But there also is a question of sustainability. If there is nothing wrong with the functionality of your vehicle, should you be replacing it with an entirely new one anyway? Surely there must be solution whereby existing heavy-duty, or off-highway fleets can be converted to a less polluting fuel alternative?
Researchers and developers are already retrofitting Hydrogen ICE’s into existing heavy-duty trucks and thereby creating a decarbonisation option without the financial outlay of an entirely new truck. Furthermore, with existing supply chains able to continue to supply the infrastructure parts for existing heavy-duty design, this also means reductions in extensive redevelopment costs and connected additional emissions if entirely new vehicles were to be produced.
Dolphin N2 has gathered three examples of the pioneering work being undertaken by developers and how their hydrogen conversion options could be a game changing opportunity for logistics and haulage companies.
University of New South Wales (UNSW)
Researchers from the University of New South Wales (UNSW) have prototyped and tested a retrofit system capable of converting diesel engines to run on 90 percent H2. The project allows for a considerable reduction in carbon dioxide and the nitrous oxide emissions while also providing a 26 percent efficiency boost.
The conversion still requires the engine to use diesel fuel for 10 percent of its operation making it not 100% emission free. However, what it does offer is a way for businesses to dramatically reduce their GHGs whilst also re-using an existing vehicle and or fleet. The reduced waste can therefore offset a considerable amount of the remaining emissions from the vehicle’s operations.
This system, like most retrofits converting diesel to hydrogen trucks and cars, does not involve the use of fuel cells, but is instead adds H2 injection directly into the cylinder. It also adds independent injection timing control for both the H2 and diesel systems. (1)
In the case of the system developed by the UNSW team, it also doesn’t require the hydrogen fuel to be high purity due to a stratification technique that forms pockets of higher and lower concentrations of H2. In this way, the nitrous oxide emissions are substantially reduced when compared to the operation of a diesel vehicle. (1)
JCB – hydrogen combustion technology.
Early in 2023 JCB announced that they installed one of their highly efficient hydrogen engines into a 7.5 tonne Mercedes truck.
The installation was completed in just a few days and one of the truck’s first test drivers was JCB Chairman Anthony Bamford, who has been spearheading JCB’s £100 million hydrogen project. (2)
The former diesel truck at the centre of JCB’s latest project is a breakthrough in hydrogen combustion technology, underlining that this sort of power could represent a much quicker way to reach global CO2 emissions targets.
“This is a giant leap forward for JCB and the rest of the world because we all have one goal: to reduce emissions. The hydrogen engine we have installed in the truck is the same as those already powering prototype JCB machines, so there is no reason we should not see hydrogen combustion engines in vehicles used on the roads in the future, including cars.” Lord Bamford – JCB Chairman (2)
EU-funded H2Engine project
The EU-funded H2Engine project has demonstrated a solution which can allow the heavy-duty sector to transform a conventional diesel truck into a ‘clean’ vehicle. By retrofitting a hydrogen engine, a truck is subsequently upgraded with hardware and software components enabling it to run on hydrogen.
Other common components developed to meet hydrogen-specific requirements include the engine’s injection and ignition systems as well as software for the engine control unit (ECU). (3)
The H2Engine team fitted a truck with a 7.8-litre hydrogen combustion engine, upgrading the core subsystems with its ‘KEYOU-inside’ technology. (3)
There is a growing interest in hydrogen-based solutions for transport systems, with vehicles fuelled by hydrogen combustion engines meeting the EU’s criteria to be considered zero-emission vehicles. As H2 only emits trace amounts of CO2, H2 vehicles are a front runner in the search for cleaner alternatives to fossil fuels.
With hydrogen combustion being comparable to the performance of traditional diesel propulsion, converting existing vehicles into environmentally friendly ones without loss of performance proves that the technology can resolve the conflict between emissions, efficiency and economy.
Written by Katy Mason for and on behalf of Dolphin N2.