In its pursuit of development and use of new power sources to achieve carbon neutrality in its products, equipment manufacturer Komatsu has partnered with German hydrogen engine startup KEYOU to develop a conceptual “world’s first” 12-cylinder, hydrogen-powered rigid-frame mining haul truck.

Based on Komatsu’s flagship large dump truck – the HD785 – the concept truck is being equipped with what both parties are calling a “hydrogen combustion engine”.

Not to be confused with hydrogen fuel cells, Komatsu says the use of hydrogen combustion engines in construction and mining equipment has the advantage of a relatively lower cost to implement because the powertrain components of existing diesel-powered machines can be used without replacement.

With a maximum payload of about 92 t, the dump truck started undergoing proof-of-concept tests, with the first firing of the hydrogen engine in January, at Komatsu’s Ibaraki Plant, in Hitachinaka City, Japan.

These tests will focus on evaluating driving performance, continuous operating hours, fuel efficiency, and verifying safety measures related to high-pressure hydrogen gas use.

Through these tests, Komatsu aims to accumulate knowledge on hydrogen engine use, laying the foundation for future development of hydrogen-powered construction and mining equipment.

With “virtually zero” CO₂ emissions, Komatsu says some mining customers have expressed interest in adopting hydrogen engines as one of the options to achieve carbon neutrality at their sites.

“Moving forward, we will continue to develop this technology as one of the key pillars of our carbon neutrality initiatives,” says Komatsu development division president, CTO and senior executive officer Taisuke Kusaba.

Diesel Base, Hydrogen Tech

While developing hydrogen engines as one of the options, Komatsu has focused on the technological expertise of KEYOU, which specialises in the development and implementation of hydrogen engines for large trucks.

The concept mining haul truck is equipped with a hydrogen combustion engine and a 700 bar hydrogen tank system, the latter being mounted on a platform beside the operator’s cab to increase hydrogen storage capacity.

To ensure clear visibility for the operator, cameras and monitors have been newly installed both inside and outside the cab.

The close cooperation between Komatsu and KEYOU was initiated at the World Hydrogen Technologies Conference in Tokyo, in 2019, where KEYOU presented on the opportunities and potential of hydrogen combustion engines, catching the attention of Komatsu.

The start of the dump truck project followed in April 2023, with the first firing of KEYOU’s hydrogen combustion engine taking place almost a year later, at KEYOU’s partner KST, in Bad Dürkheim, Germany.

In addition to the Komatsu partnership, KEYOU is implementing a number of development projects for other selected original-equipment manufacturers, supporting them in efforts to make existing internal combustion engines hydrogen-ready, for both on-road and off-road applications.

“Our partnership with Komatsu is currently our most important customer project in the off-road commercial vehicle sector and demonstrates the performance capabilities of KEYOU-inside technology under extreme conditions,” explains KEYOU COO and CTO Markus Schneider.

In terms of fuel supply, Komatsu says while there are challenges such as safety management and infrastructure for hydrogen supply, it will work to address these issues in collaboration with industry associations and other related stakeholders.

Under its mid-term management plan, Komatsu has set the goal of reducing CO₂ emissions by 50%, compared to 2010 levels, from its products in use and in its production operations, each by 2030, with the challenging target of achieving carbon neutrality by 2050.

In line with these efforts, the company has, to date, introduced hydraulic excavators, tethered electric hydraulic excavators, and small and medium-sized battery-powered hydraulic excavators to the market.

In addition, Komatsu is working on various environmentally responsive technologies from all aspects, including the use of carbon-neutral fuels, the development of power supply systems for battery-equipped construction equipment, proof-of-concept tests for a hydrogen fuel cell- powered excavator, and the development of a power agnostic truck that is capable of operating with multiple power sources, including diesel-electric, battery-electric, trolley (wired), fuel cell and hydrogen.