Osaka Gas: the e-methane plant in Nagaoka has started trial operation and feeds the existing gas grid

Osaka Gas reported in May 2026 that in February it had started trial operation of a plant producing e-methane in Nagaoka in Niigata Prefecture, built jointly with Inpex. The annual production capacity corresponds to the gas demand of about 10,000 households, and the synthetic gas is already being injected into existing pipelines.

What e-methane is and why inject it

E-methane is methane produced from hydrogen obtained from renewable sources and CO₂. According to Jiji Press, because the CO₂ used in the process is taken from the air, its amount in the atmosphere does not increase when the synthetic gas is burned. The main components of e-methane are the same as those of natural gas, so existing pipelines and other gas installations can be used. Osaka Gas assumes that in fiscal year 2030 e-methane will replace 1% of the city gas feedstock.

Supply plans

The company intends to source e-methane from the United States too, to diversify supply in the face of the risk of LNG supply disruptions linked to tensions in the Middle East. Osaka Gas is taking part in a project in Nebraska led by a TotalEnergies subsidiary together with Toho Gas and Itochu; production is to start in fiscal year 2030 at about 75,000 tonnes a year.

Use during Expo 2025

According to Jiji Press, during Expo 2025 in Osaka the company ran a test of producing e-methane from waste generated at the exhibition site; the gas was used in kitchens in facilities, including the state guest house.

The challenge: cost

E-methane remains expensive to produce; mass-production technologies are needed to bring costs down. The scale of 10,000 households is very small compared with Japan's total gas demand.

Significance for biomethane

For the biomethane market, this is a signal that Japanese gas companies are betting on synthetic gas injected into the existing grid, and the Expo 2025 project also shows an attempt to link waste with e-methane production. The Nebraska plan envisages exporting e-methane to Japan using existing pipelines and LNG facilities in the USA (the gas would reach Japan by ship as LNG).

Conclusion

The Nagaoka plant is a pilot, not a commercial breakthrough. Its significance will be determined by falling costs and the availability of renewable CO₂ and cheap electricity.