The company has already started building its second solar project in Japan.
It expects to finish the 10.5 MW array in Nogata, Fukuoka prefecture, in the second quarter of 2017.
It also appears set to connect an additional 2 MW of PV to the grid in Ryohashiya, Fukui prefecture, by the first quarter of 2017.
The Bangkok-listed group which primarily operates zinc ore mines throughout Southeast Asia began investing in renewables in 2014, via its PDI Energy subsidiary.
In early September, Thai media revealed Padaeng Industrys plans to invest t1.5 billion baht ($43.2 million) in the development of at least 13 MW of solar capacity in Japan.
The company is the latest in a number of Thai players along with Gunkul Engineering and Bangkok-based developer SPCG to jump into PV investment in Japan, just as the market is shifting away from utility-scale development to a greater focus on residential deployment.