• Japanese automaker Daihatsu will publicly display an actual ammonia/hydrogen co-firing engine for the first time at Japan Mobility Show Bizweek 2026.

• The system converts part of its onboard ammonia into hydrogen before co-firing the two fuels, with Daihatsu now seeking partners for ammonia reforming, emissions treatment, safety and fuel-supply infrastructure.

 

Daihatsu will unveil an actual development-stage ammonia/hydrogen co-firing engine for the first time this month, as the Japanese automaker steps up work on an alternative combustion system designed to use ammonia as both a fuel and hydrogen carrier.

 

The engine will be shown at Japan Mobility Show Bizweek 2026, running from October 13-16 at Makuhari Messe in Chiba, Japan.

 

Rather than relying solely on ammonia combustion, Daihatsu's system takes some of the ammonia stored in a dedicated onboard tank and converts it into hydrogen using a plasma reactor and catalyst installed above the engine.

 

The resulting hydrogen is then burned together with ammonia.

 

The approach is intended to address one of ammonia's fundamental problems as an engine fuel: it is considerably more difficult to ignite than conventional fuels. Adding hydrogen is intended to improve combustion stability while allowing ammonia's relatively high energy density and easier liquefaction to support vehicle driving range.

 

Daihatsu has not announced performance figures, efficiency, engine output or a timetable for commercial production. The engine remains under development.

 

The company is now looking for outside partners to work on some of the technical and infrastructure problems that would have to be solved before the technology could move towards practical deployment.

 

These include ammonia reforming, exhaust-gas purification, system downsizing, safety technology and the infrastructure required to supply the fuel.

 

The actual engine will be displayed as part of the Japan Automobile Manufacturers Association's joint exhibition at the event.

 

Ammonia Used as Both Fuel and Hydrogen Carrier

 

The design reflects growing interest in ammonia not only as a potential carbon-free combustion fuel, but also as a means of carrying hydrogen.

 

Ammonia can be liquefied more readily than hydrogen and has a comparatively high volumetric energy density. Daihatsu's approach effectively uses the vehicle's ammonia supply for two purposes — directly as an engine fuel and as the feedstock for producing the hydrogen needed to support combustion.

 

The company says co-firing hydrogen with the difficult-to-ignite ammonia is intended to provide stable combustion while maintaining sufficient driving range.

 

However, Daihatsu has not said whether the ammonia used in a future commercial vehicle would be renewable or low-carbon.

 

That distinction would ultimately determine much of the system's lifecycle carbon benefit, since ammonia itself contains no carbon but its production can carry substantial emissions when made conventionally from fossil fuels.

 

BEVs Become Mobile Batteries

The ammonia/hydrogen engine will form part of a broader group of technologies Daihatsu is presenting under the theme of "Connecting Energy."

 

The company will also show a regional microgrid combining solar generation, stationary batteries and battery-electric vehicles.

 

Daihatsu's system treats BEVs as mobile energy-storage units and combines them with power-conversion equipment, including the Smart Power Hub, housed in a transportable container.

 

During normal operation, the system is intended to reduce peak electricity demand and CO₂ emissions. During disasters or other grid outages, it can continue supplying electricity to help maintain public services.

 

Demonstration testing of the concept has been underway since last year.

 

Cow Manure Turned Into Fuel for Car Production

Daihatsu will also present a separate circular-energy project being developed around its Shiga (Ryuo) manufacturing plant.

 

The project links agriculture, livestock farming and vehicle manufacturing in Ryuo Town.

 

Manure from Omi cattle is used to produce biogas, which can then be used as a carbon-neutral fuel at the vehicle manufacturing plant. Compost and liquid fertiliser left after fermentation are returned to agricultural use.

 

Alongside its energy projects, Daihatsu will demonstrate AI-based manufacturing and customer applications and its "GOISSHO" shared transportation service for welfare and nursing-care facilities.

 

But the ammonia/hydrogen engine is the most significant new energy technology being presented.

 

Its first physical public display moves the programme beyond a conceptual vehicle installation. Daihatsu is also openly acknowledging that several significant engineering and infrastructure hurdles remain — and is now looking for partners capable of helping solve them.

 

Source:   FCW Team