Osaka Gas tests bioplastic-to-energy conversion with partners

Osaka Gas Co. has conducted a demonstration project converting
used bioplastic bento containers into energy, highlighting efforts
to find effective uses for such materials despite government
promotion, Kyodo News reports.

The company explored biomass gasification at a sewage treatment
facility in collaboration with the Osaka municipal government and
Osaka Metropolitan University, targeting potential commercial
application around 2030.

In the joint trial, lactic acid derived from the decomposition
of nearly 1,000 used bioplastic containers collected from a
university cafeteria was added to sewage sludge in a digester tank
at a facility in Osaka. The process was repeated several times
between December 2025 and March, the company said.

The project has been completed, with both the breakdown of the
containers into lactic acid and their conversion into biogas
proceeding smoothly, although detailed results were not
disclosed.

According to Osaka Gas, earlier small-scale testing showed that
adding lactic acid to sewage sludge increased biogas output by
around threefold. Based on estimates using 3,500 containers, the
volume of biogas produced would be sufficient to meet the daily
energy needs of about 30 households.

The company indicated that wider adoption of bioplastics will be
necessary to supply sufficient feedstock for community-scale energy
production once the technology is commercialised.

A key factor in expanding biogas use will be the government’s
ability to raise bioplastics consumption to about 2mn tonnes by
2030, up from 150,000 tonnes in 2022, according to people familiar
with the matter.

The trial forms part of broader efforts within the gas industry
to replace carbon-intensive natural gas with lower-emission
alternatives, including biogas and e-methane synthesised from CO2
and hydrogen, in city gas networks as part of decarbonisation
strategies.