© Daimler Truck

Germany’s KEYOU will convert Daimler internal combustion engine trucks to run on hydrogen under a new partnership targeting commercial launch of the converted tractor unit in 2027. The deal marks the first time Daimler has backed a hydrogen combustion programme, having previously concentrated its zero-emission investment on battery-electric and fuel cell technology.

Hydrogen ICE as a Lower-Cost Route to Decarbonization

The agreement positions hydrogen internal combustion engines (ICE) as a pragmatic, potentially cheaper way to introduce zero-carbon fuels in heavy-duty transport, since the technology draws on existing engine manufacturing expertise rather than requiring fuel cell stacks or large battery packs. It also adds a third zero-emission powertrain to the Actros platform, alongside the battery-electric variant already on sale and the NextGenH2 fuel cell truck due for customer deployment later this year, with Daimler having separately unveiled a liquid hydrogen fuel cell truck aimed at 2026 production.

Commercial Terms and Technical Specifications

Under the deal, KEYOU will purchase Mercedes-Benz Actros L 1848 tractor units and OM 471 diesel engines from Daimler’s Mannheim plant and modify them into a 350kW port fuel injection truck capable of carrying up to 40 tonnes gross vehicle weight. The majority of the original engine is left unchanged in the conversion. The resulting vehicle, named the KEYOU Hice.40, uses 350-bar compressed hydrogen tanks for a claimed range of up to 650km (400 miles); refuelling time for this 40-tonne variant has not been disclosed, though KEYOU’s smaller 18-tonne truck refuels in about 15 minutes.

KEYOU will sell the converted trucks directly to fleet customers, with conversion support from Bücker + Essing of the Elevion Group. Financing is available through GML Gesellschaft für Mittelstandsleasing, and Keyou has separately agreed an “H2 Mobility as a Service” bundle with German renewable energy company GP Joule covering maintenance, roadside assistance and optional insurance. Andreas Gorbach, Daimler Truck’s board member for truck technology, said the company was partnering with a specialised company to bring hydrogen combustion technology to market quickly and efficiently. Daimler describes the arrangement as a partnership rather than in-house development.

Keyou Track Record

KEYOU, founded in 2015 by three former BMW powertrain engineers, delivered an 18-tonne hydrogen ICE truck to German logistics firm EP-Trans in early 2025, after the operator ruled out battery-electric alternatives, and has worked with Japan’s Komatsu on hydrogen-powered construction equipment, including proof-of-concept tests for what was described as the first hydrogen-powered dump truck. The company received TÜV Süd road certification for that 18-tonne truck and claimed a hydrogen combustion engine efficiency record of 44.5% in 2018. Its investors include the BESTO family office and the European Innovation Council, which contributed €5.8m.

Regulatory Uncertainty Over Emissions Status

Hydrogen ICEs still produce nitrogen oxides when combusted, meaning they are not classified as zero-emission and are often ineligible for the subsidies and tax incentives extended to battery-electric and fuel cell vehicles. Hydrogen trucking group H2Accelerate called on EU policymakers last October to treat hydrogen ICE vehicles the same as zero-emission alternatives. This sits in tension with a separate provision under the EU’s heavy-duty vehicle CO2 standards, which tighten from 2030, under which hydrogen combustion trucks emitting less than 3g of CO2 per tonne-kilometer qualify for the same zero-emission classification as battery-electric and fuel cell trucks — a discrepancy that has not been resolved between the regulatory frameworks.

Implications

The unresolved emissions classification is the central commercial question for hydrogen ICE trucks: if they remain excluded from incentives available to fuel cell and battery-electric vehicles despite qualifying under the CO2 standard, the cost advantage of using existing engine manufacturing could be offset by lost subsidy access. For Daimler, the KEYOU deal allows it to test hydrogen combustion through an external partner without committing in-house development resources, while keeping pace with other companies as the heavy-duty sector hedges across multiple zero-emission technologies ahead of the EU’s 2030 standards.