Itochu owns a 50% interest in the installation, while Fuyo General Lease holds 25%. A joint venture between Tokyo-based Shinwa Energy and gas specialist Saisan has also taken a 25% stake.
Toshiba handled EPC services, while construction firm Obayashi helped to develop the site. The PV module supplier was not disclosed.
The array will annually generate about 43 million kWh, or enough electricity for roughly 7,600 homes, according to an online statement.
The electricity will be sold to regional utility Chugoku Electric Power over a period of 20 years.
Mizuho Bank arranged loans to back construction, in cooperation with several other undisclosed banks. Itochu did not reveal the financial terms of the project, which was first announced in late 2014.
Itochu is now building 130 MW of capacity, with plans to expand its pipeline to 200 MW, according to an online statement.
In June 2015, it switched on its first PV array, a 33.79 MW project in Saijo, Ehime prefecture.
In January 2016, Itochu finalized a deal with Bank of Fukuoka to finance the development of 21 MW in Karatsu, Saga prefecture.
And last March, it switched on a 44.8 MW array in Hiyoshibaru, Oita prefecture.