Biogas-based Cogeneration, PV Generation Combined at Sewage Plant

2014/03/07 20:00
Kenji Kaneko, Nikkei BP CleanTech Institute

Energy Bank Japan (EBJ) Co announced March 5, 2014, that it has launched a power production business using a biogas-based cogeneration system in addition to a solar power generation system at Tarumi Sewage Plant in Kobe City.

EBJ is a wholly-owned subsidiary of Osaka Gas Co Ltd and is based in Chuo Ward, Osaka. The power production business is a joint project with Kobe City and was named "Kobe W Eco Power Generation Project."

On the facilities of the sewage plant, a 2MW mega-solar (large-scale solar) power plant was installed. And 350W of biogas-based cogeneration facilities were installed on the property of the same sewage plant. It is Japan's first power generation system that uses both PV power generation and biogas-based cogeneration.

Biogas is an inflammable gas whose main component is methane, which is generated when an organic substance (e.g. sewage sludge and food residue) ferments. Kobe City has been making efforts to effectively use biogas by, for example, starting to inject biogas into the pipes for city gas on a trial basis in fiscal 2010 for the first time in Japan.

Osaka Gas established EBJ in April 2010 and since then has been providing services that enable customers to install renewable energy-based power generation facilities without initial investment. Based on the services, EBJ established a scheme that includes the technical evaluation, engineering and maintenance of power generation facilities. And it is running power generation businesses in collaboration with municipalities.

As of the end of December 2013, the company had concluded contracts to install a total of about 26MW of solar power generation facilities.

The scheme for the new project was established using EBJ's financing technique. The company raised capital, installed power generation facilities and began to operate them. Kobe City provides the business site and biogas. EBJ concluded a contract to sell electricity based on the feed-in tariff (FIT) scheme. And part of the profit that EBJ earns by selling electricity will be transferred to Kobe City in accordance with the amount of electricity sold.