Automakers Subaru, Mazda, and Toyota collaborate on lowering engine carbon emissions via joint innovation and competitive spirit.
Japanese Automakers Embrace Traditional Engines in Carbon-Neutral Strategy
In a joint workshop, Subaru, Mazda, and Toyota emphasized the continued importance of traditional engines such as Toyota's inline 4-cylinder, Subaru's horizontally-opposed (boxer), and Mazda's rotary engines in achieving carbon neutrality in the electrification era.
The workshop, held on May 28, marked a significant step forward in the automakers' plans to co-develop next-generation petrol engines designed to be more efficient and high-performance while running on carbon-neutral or low-carbon fuels.
Rather than relying solely on electric vehicles (EVs), these Japanese automakers promote a diversified carbon neutrality approach. This involves combining electrification with continued improvements in combustion engines, including efficiency gains and alternative fuels usage such as carbon-neutral synthetic fuels or hydrogen.
Toyota, for instance, is refining its technology to achieve higher efficiency by leveraging the respective areas in which electric motors and engines excel. The company is developing new low-displacement inline 4-cylinder engines, aiming to thoroughly refine the characteristics of these engines and develop them into powertrains that can create diverse cars in the age of carbon neutrality.
The inline 4-cylinder engine has a long history of refinement and versatility, supporting a diverse product lineup from family cars to sports cars. Toyota President Koji Sato emphasized the need to refine engine characteristics to create diverse cars, stating that the company aims to make it possible to create hybrid and plug-in hybrid vehicles that are "electric-rich."
Subaru’s boxer engine, Mazda’s rotary engine, and Toyota’s inline 4-cylinder engines possess distinctive characteristics like compactness and smoothness, which can be enhanced for reduced emissions. Evolving these traditional engines to run on hydrogen or synthetic carbon-neutral fuels may provide an interim or complementary solution to full electrification, addressing challenges like energy storage, charging infrastructure, and range.
The trio acknowledges the legacy value and specific technical advantages of their unique engine architectures. Each company is pursuing its own battery EV initiatives in addition to new engine developments. Toyota, along with Idemitsu Kosan, ENEOS, and Mitsubishi Heavy Industries, aims to consider establishing a carbon-neutral fuel supply chain.
The focus of the workshop was on developments of new engines for the electrification era. Over the past few years, the companies have been refining their engine technology in motorsports, leveraging what is unique to Subaru, Mazda, and Toyota. The leaders shared their thoughts on the initiatives, with Toyota President Koji Sato discussing a multi-pathway approach to carbon neutrality at the Multipathway Workshop.
This approach arises partly from the companies’ current positions in the EV market—they are comparatively behind global leaders in full electrification and thus emphasize improving internal combustion engines alongside accelerating EV development. The joint workshop by Subaru, Mazda, and Toyota views advanced, efficient versions of their traditional engines as a vital component of a multi-pathway strategy toward carbon neutrality, bridging the current gap between legacy internal combustion technology and the future electrified transportation landscape. This reflects a pragmatic and gradual adaptation rather than outright abandonment of petrol engines in the carbon-neutral transition.
- In their joint carbon-neutral strategy, Subaru, Mazda, and Toyota, while developing new battery electric vehicles (EVs), are also focusing on refining traditional engines like the inline 4-cylinder (Toyota), Subaru's boxer, and Mazda's rotary engines to run on carbon-neutral or low-carbon fuels, such as hydrogen or synthetic fuels, in the financing and technology sectors.
- While promoting electrification, the Japanese automakers, including Toyota, Subaru, and Mazda, are simultaneously emphasizing the role of traditional engines like the inline 4-cylinder in transportation, as these engines can be evolved to reduce emissions, provide interim solutions to challenges like energy storage, and contribute to a diversified carbon-neutral strategy rather than solely relying on electric vehicles.
