Toyota, oil company Idemitsu Kosan and two other Japanese companies said Monday they have launched a joint study on introducing and promoting carbon-neutral fuels for automobiles.

With the aim to introduce these fuels around 2030, the four companies — also including oil company Eneos and Mitsubishi Heavy Industries — will consider methods for mass production and related systems.

Specifically, the four will jointly explore ways to commercialize "e-fuels," or synthetic fuels produced from hydrogen and carbon dioxide refined with renewable energy, and plant-based biofuels.

Toyota will also independently develop engines that can use such fuels efficiently.

Carbon-neutral fuels have the potential to be used in existing engine vehicles. Refueling times are as short as gasoline, while electric vehicles require long charging times.

Given these advantages, Toyota sees carbon-neutral fuels as a promising tool for promoting the decarbonization of automobiles.