On October 1, an official completion ceremony was held for the Toyohashi City Biomass Utilization Center in Toyohashi City, Aichi Prefecture, Japan. The project is the largest integrated renewable energy facility for the combined anaerobic digestion (AD) treatment of sewage sludge, septic tank sludge and food waste, which up to now had been treated separately, solar PV and digestate carbonisation into a biomass fuel.
A large number of distinguished guests and related persons attended the ceremony. The Mayor of Toyohashi City, Koichi Sahara, commented that he “hopes this advanced scheme to utilize waste and sewage sludge as resources will become a standard for Japan as a whole.”
The integrated treatment process not only achieves effective utilization of energy from waste that previously was not recovered but it also realizes complete energy conversion by converting the digestate into a fuel sold externally by using a carbonization process.
In comparison with treatment by separate facilities, this combined treatment plant makes it possible to reduce the costs of construction, maintenance and operation.
BOT model
Commissioned by the client, Toyohashi City, the plant is built using the build, transfer and operate (BTO) method of the private finance initiative (PFI). In this method, a private company raises construction funds. After the completion of the facilities, ownership is transferred to Toyohashi City, and the private company runs the facilities.
The project to build and operate the facilities consists of:
- a business of selling electricity generated by the biogas power plant,
- a business of selling fermented sludge to other companies as carbonized fuel and
- a business of large-scale solar power plant using idled land (as a subsidiary business).
The operating body of Toyohashi City Biomass Utilization Center is Toyohashi Bio Will KK, a special purpose company (SPC) financed by JFE Engineering Corp, Kajima Corp, Kajima Environment Engineering Corp and Otec. Toyohashi Bio Will KK, will perform maintenance and operation for a period of 20 years, and the power generated by the facility will be sold using the FIT scheme.
JFE Engineering expects that similar integrated treatment facilities would become popular among local governments throughout Japan in the future. Using the Toyohashi plant as an advanced model, the company will actively propose such solutions to local governments in Japan and across other regions in Southeast Asia where urbanization is progressing rapidly, and not only power shortages but also the treatment of sewage sludge and food waste have become issues.
