Synthetic methane is produced through methanation, a process that combines hydrogen and CO₂ to create methane—the main component of natural gas.

When hydrogen is produced from renewable sources—such as green hydrogen generated via electrolysis using surplus solar power—the CO₂ emitted during combustion is offset by the CO₂ captured during synthesis, resulting in no net increase in atmospheric CO₂. This achieves carbon neutrality by balancing emissions with removals.

Synthetic methane made from non-fossil energy sources like green hydrogen is called e-methane, and it is considered a clean, carbon-neutral energy solution.

E-methane is gaining attention due to its advantages in cost, safety, and raw material availability.

First, it is cost-effective because e-methane shares the same properties as methane—the main component of Liquefied Natural Gas (LNG)—allowing the use of existing natural gas infrastructure without fuel conversion. It can also be blended with LNG, enabling a smooth and gradual transition toward carbon neutrality.

In terms of safety, e-methane can be regulated under the existing safety standards for LNG, making additional regulations generally unnecessary.

Regarding raw materials, e-methane can be produced at a much larger scale than biomethane. Promoting methanation within Japan is expected to enhance energy self-sufficiency and ensure a more stable domestic energy supply.

In November 2020, Japan’s gas industry pledged to achieve carbon-neutral gas by 2050, contributing to a decarbonized society. To this end, the industry is pursuing next-generation thermal energy solutions through strategies such as methanation and direct hydrogen utilization.

To guide progress toward 2050, an action plan has been outlined with three key pillars:

As a milestone, the industry has set a goal of achieving a carbon-neutral gas rate of 5 % or more by 2030. This includes injecting at least 1 % carbon-neutral methane into natural gas pipelines as an initial step toward implementing methanation.