A number of OEMs have publicly dedicated to hydrogen combustion engines for future mid-size and heavy tools. However are they market-ready and is the market prepared for them?
Whereas battery expertise and electrification are making market progress as sensible different energy choices for compact development and agriculture automobiles, nearly all of producers would seem satisfied hydrogen-fuelled variations of typical engine bases supply one of the best mix of attributes for heavier machines and better energy calls for. However though latest years have seen loads of prototype unveilings at commerce exhibitions and press occasions, full market availability and broad trade adoption of such energy expertise would seem nonetheless a way off.
Whereas the framework has lengthy been in place to provide, retailer and dispense liquid fuels and electrical energy, growth of the required expertise and infrastructure to do the identical with hydrogen is probably a superb few steps behind that of the machines that may use the gas. It’s this that might look like what the market must spark demand for hydrogen-fuelled farm and development tools. However is it that easy? What stage are producers at with their machines?
Refuelling growth
Whereas initially trialling hydrogen gas cell expertise to energy a prototype 360-degree excavator, JCB latterly shifted its hydrogen focus to much less complicated and extra responsive hydrogen-fuelled inner combustion engines, with the added advantages of much less cooling demand and much-reduced weight over a battery-based hydrogen gas cell unit. Effectively-established in its dedication to hydrogen engine energy for its bigger automobiles, having publicly demonstrated backhoe loader and construction-spec telehandler working prototypes, JCB has gone some technique to additionally develop the required expertise to assist hydrogen-engined automobiles.
“Our hydrogen engine growth isn’t a conversion, however new combustion expertise,” says Ryan Ballard, engineering director for powertrain at JCB, talking concerning the firm’s four-cylinder engine that options in these working prototypes, and which was given its standalone world debut finally 12 months’s ConExpo.
“Due to the totally different traits of a gasoline gas in comparison with a liquid one, it requires a very totally different low-pressure, low-temperature combustion course of. Now we have developed a selected oil and additive pack that, at low preliminary engine temperatures, traps the water produced as a combustion by-product. Because the engine warms to working temperature, that water then dissipates.
“We’ve additionally developed a high-efficiency turbocharger that forces far more air into the engine than
a normal unit, serving to maximise hydrogen combustion effectivity.”
However whereas the precept of the engine has now been established for a while, the infrastructure required to assist it and others prefer it – and the practicalities of fuelling a machine powered by the unit – are one thing JCB has solely addressed extra lately, with the revealing of its cell hydrogen refueller.
Based mostly on the stretched platform of one in every of its Fastrac 4000-series tractors, the refueller is designed to switch hydrogen gas between on-site bulk storage and hydrogen-powered machines. It options commonplace nozzle expertise for hydrogen gas supply from refueller to machine, and refuelling time is comparable with that required for refilling with diesel, while the unit’s capability provides it the power to offer as much as 16 refills earlier than the unit itself wants replenishing. The corporate suggests this technique will go well with most customers in that it mirrors how they already handle the refuelling necessities of diesel-powered machines.
Manitou prototypes
Amongst different dealing with tools makers, Manitou Group says that, by 2030, low-emissions merchandise – electrical plus hydrogen – will symbolize 43% of its product line. The agency has opened devoted amenities for hydrogen-powered machine growth and has a hydrogen-powered prototype telehandler – based mostly on an current 18m-reach development machine – in growth, with exams ongoing to ensure vary and reliability in real-life situations, plus element sturdiness. Whereas this preliminary prototype makes use of gas cell expertise, Manitou says it’ll finally choose the hydrogen energy system greatest suited to its prospects’ wants.
“We’re finding out all of the hydrogen-related applied sciences based mostly on what customers want,” says Michel Denis, president and CEO of Manitou. “This present prototype is just step one – a second rotating telehandler prototype will likely be developed within the coming months.”
To develop an answer suited to full industrialisation, assist from public authorities to develop an rising ecosystem is essential, emphasises Julien Waechter, Manitou Group vice-president of R&D. “The inexperienced hydrogen sector is step by step turning into extra established with the entry of extra gamers,” he says. “All the assist mechanisms proposed by the totally different governments will encourage the transition to hydrogen, and can pace up the event of the distribution community and finally the discount within the utilization prices of our machines utilizing this vitality. Our intention is to have a 100% hydrogen-powered telehandler available on the market by 2026.”
Whereas JCB has arguably taken a sector lead in hydrogen-engined off-highway car growth, different multinational OEMs are additionally committing critical R&D cash to hydrogen engine automobiles. Elsewhere within the development sector, Liebherr continues to work on its H964 four-cylinder and H966 six-cylinder engines, the latter having been developed at the side of the agency’s R 9XX H2 excavator. Collection manufacturing of its hydrogen engines is predicted to start in 2025.
Injection challenges
With greater injection stress and the publicity to combustion pressures and temperatures elevating necessities on injector tightness and sturdiness, Liebherr continues to check its H2 gas injectors and full injection methods for secure and correct direct injection operation. Utilizing a system-oriented method to hydrogen injection, the intention is to match the efficiency of an H2 DI engine to that of a diesel engine, requiring any system to be able to making certain excessive move charges.
Because of the low density of hydrogen gasoline, an injector wants giant valve cross-sections. To allow exact management of small portions, the system stress have to be regulated with pinpoint accuracy, factors out Liebherr. Within the agency’s hydrogen injection system, that is achieved through a gasoline quantity management valve, working alongside different pressure- and flow-regulating parts to create a system-oriented method to hydrogen injection. Along with its direct injection actions, Liebherr says it’s working in parallel on consumption manifold injection parts to fulfill totally different engine necessities.
The corporate has been working with Mahle Powertrain to include the latter’s prechamber jet ignition system (MJI), with engine exams exhibiting that its use can combust the hydrogen/air combine at a excessive compression ratio, maximising the method’s stability and effectivity and enhancing inexperienced hydrogen’s suitability for heavy-duty and off-road purposes.
“The problem is to cease engine knocking and untimely ignition with out lowering the compression ratio and thus effectivity and efficiency yield,” says Mike Bunce, head of analysis for Mahle Powertrain US. “To be able to obtain secure operation with a excessive compression ratio while avoiding engine knock and pre-ignition, hydrogen engines have to be operated with a considerable amount of air. The vitality from a traditional spark plug is inadequate to ignite such a combination. Our Jet Ignition solves the issue by burning a small quantity of an ignitable combination in a prechamber. The ensuing gasoline plasma is handed via small openings into the primary combustion chamber and, as a consequence of its excessive vitality content material, quickly and evenly ignites the primary gasoline combination. Exams with Liebherr’s H966 and H964 engines have delivered wonderful outcomes by way of combustion pace, efficiency and emissions.”
Indian push
By way of agricultural automobiles, Indian tractor large TAFE used Agritechnica 2023 to mark its broader push into the total western European farm tractor market by unveiling to attendees each battery- and hydrogen-powered developments.
Ravindran Vijayakumar, the corporate’s chief engineer, has revealed that the modified Simpson engine within the tractor produces 55hp/41kW from its three cylinders, however has additionally acknowledged that little additional info will likely be out there till additional growth had been carried out.
“It is a fully-working prototype, and we all know we will carry adequate gas for lengthy working intervals, with our design engineers having integrated appreciable gas storage functionality into the tractor via purpose-designed tanks behind the operator’s seat and beneath the platform ground,” says Vijayakumar. “That will likely be one of the essential points of machine acceptance. A tractor with this gas sort can be focused initially at markets with the infrastructure to assist it, which is why we’re making a concerted push into western Europe.”
By way of corporations targeted solely on manufacturing engines for OEMs, Antonio Leitao, vice-president of off-highway engine enterprise at Cummins, additionally used Agritechnica to underline the corporate’s dedication to hydrogen as a gas for the event of future sustainable drivetrains. By creating options aligned with present car designs, the corporate is ready to minimise complexity for OEMs and end-users, whereas utilizing a foundation of current parts the place potential gives the maker with economies of scale potentialities and prospects with reliability and sturdiness equal to diesel.
“Hydrogen-fuelled inner combustion engines can meet the calls for of essentially the most difficult purposes, offering the robustness similar to a diesel engine to fulfill agriculture’s excessive working and environmental situations,” says Leitao. “The first distinction is within the machine’s on-board gas storage. Via our three way partnership with NPROXX, a specialist in excessive stress hydrogen storage for each stationary and cell purposes, we’re working to assist OEMs with the event of storage tanks offering as much as 700-bar stress functionality to maximise capability.”
Solely ag
With a most energy ranking of 290hp (216kW) and 1,200Nm peak, Cummins says its B6.7H hydrogen engine is aimed squarely on the calls for of agricultural tractors and different machines. Based mostly on a next-generation Stage VI/Tier 5 platform, the engine’s base is unchanged from the six-cylinder block on the agency’s commonplace B6.7. Cummins calls the engine’s design ‘agnostic’, that means it allows constant mounting/house declare for clear diesel, pure gasoline or hydrogen fuelling infrastructure, and it’s the cylinder head and gas system which might be chief variations.
“We imagine hydrogen gas cells can supply an environment friendly energy resolution for heavy-duty purposes with excessive utilisation and vitality calls for, whereas assembly zero-emission wants, working alongside battery expertise – ultra-capacitors, lithium-ion, or lead-acid – in a parallel hybrid set-up to ship instantaneous response,” says Leitao. “We see hydrogen engines and gas cells as complementary energy sources providing totally different choices to prospects relying on the place they’re on their path to zero carbon. Introducing hydrogen engines out there can even speed up the expansion of hydrogen infrastructure to assist the widespread adoption of gas cell powertrains.”
This text first appeared within the June version of iVT Worldwide – https://ivt.mydigitalpublication.co.uk/june-july-2024
