Mazda showcases on-board CO2 capture tech

MAZDA Motor Corporation has announced that it has begun demonstration experiments of Mazda Mobile Carbon Capture, its unique on-board CO2 capture system said to further assist in reducing the manufacturer’s vehicular greenhouse gas emissions.

Showcased at the Japan Mobility Show 2025, the technology works in unison with biodiesel fuel technology and a zeolite ‘filter’ to absorb carbon dioxide from the vehicle’s exhaust gases.

Little other technical information is offered on the system, Mazda stating only that it will be tested in the Super Taikyu racing series to help realise its goal of sustainable mobility.

The Japanese manufacturer also demonstrated its Vision X-Coupe that runs on a turbocharged twin-rotor microalgae-fuelled ICE engine and electric motor PHEV system capable of travelling up to 800km between refilling and recharging.

Speaking at the event, Mazda Motor Corporation chief technology Ryuichi Umeshita said the technology will not only be environmentally friendly, but also enjoyable to drive.

“We have continuously pursued cars that feel good to drive, with particular attention to handling and ride comfort,” he stated.

“That commitment will never change. But our responsibility as a company to contribute to the environment has grown.

“We also realise that customers can’t purely enjoy driving unless they know their cars come from a company that’s environmentally responsible and truly contributes to society.

“We want people to feel the joy of driving from the heart. That’s what the Mazda Vision X-Coupe represents.

Mr Umeshita said that unlike other green vehicular technologies, the Mazda system aims to be better for the environment the further it is driven.

“Until now, we’ve developed technologies aimed at reducing environmental impact and minimising negative effects. This time we’re going further: The more you drive, the more you fuel a sustainable tomorrow,” he explained.

“In other words, the more the car is driven, the more it helps reduce atmospheric CO2 and creates a positive impact on the environment.

“And because of this positive feeling, you can enjoy the joy of driving even more purely, more wholeheartedly. Your enjoyment actually benefits society and the planet. That’s the message we’re sending.

Kazuo Ichikawa from the Advanced Environmental Technology Research Field, who researches carbon-neutral fuels, added weight to Mr Umeshita’s words, explaining that the Vision-X Coupe is one of the first vehicles of its kind to make use of microalgae and CO2 capture technology.

“(This fuel) is a type of plant-based biofuel, and like fossil fuels, it emits CO2 during driving,” he said.

“But the algae absorb CO2 through photosynthesis as they grow. So, the emissions are effectively zero.

Biofuels are already widespread in Japan and are available at regular service stations.

But microalgae have an extremely high oil storage capacity compared to common biofuels like corn-based ones.

They can efficiently produce fuel in limited space, which is why they are attracting so much attention.

“What is revolutionary this time is that we have added CO2 capture technology on top of this biofuel,” added Mr Ichikawa.

“Were not just absorbing atmospheric CO2 to grow microalgae. We are also capturing CO2 from exhaust gases during driving.

“Then we can use that captured CO2 to grow more microalgae or repurpose it to promote the growth of crops like tomatoes and strawberries or turn it into high-performance carbon materials for car parts.

“So, we’re not just achieving carbon neutrality. We’re achieving carbon negativity where CO2 actually decreases the more you drive.

“We’re turning CO2 from waste into a valuable resource and creating a sustainable cycle.

The cycle shows promise for other applications beyond vehicle fuels, the microalgae able to be grown at relatively low cost for use as a raw material for food and supplements, and even as livestock feed.

As for the rotary engine, it is now evident that the once highly polluting unit may have finally found its forte.

“The rotary engine is characterised by the unique feel of its revs, and its satisfying sound and power delivery. It’s truly an engine where you can experience the joy of driving. It’s technology that has a special place in our heart at Mazda,” said Mr Umeshita.

“But (in) considering the environmental impacts from exhaust gases, we ended mass production in 2012.

“However, we were determined to revive the rotary engine, and we relaunched a new project team in early 2024.

“We’re developing a new rotary engine that has overcome challenges while enhancing its appeal.

“As a generator, we’ve finally reached the point where we can meet strict environmental regulations in Europe and America, so we decided to install it in this vision model as well.

“Any car enthusiast will be able to sense how much passion the engineers poured into this rotary engine.

The sentiments around Mazda’s beloved rotary engine were echoed by Mr Ichikawa.

“I have very high expectations for Mazda’s new rotary engine too. Before being a researcher, I’m a huge car enthusiast,” he enthused.

“As Umeshita-san says, the sound and the feel of the engine are important elements for car enthusiasts. They create that ‘Ready, set…’ moment of anticipation in the driver’s seat, and for me that’s the starting point for the joy of driving.