There are over 2000 golf courses in Japan, with the game reaching the peak of its popularity during the "company golf" craze in the 1980s and 1990s when the number of new golfers peaked at one million a year. Subsequently, the number of people playing the sport has waned in recent years, and golf courses have gone out of business, with many sites left vacant and abandoned.

Dwindling membership meant the Suwa Golf Club, Nagano prefecture, was forced into bankruptcy, leaving the landowners with the costs of unpaid leases and property taxes.

A local developer Sun Holdings, which maintains a minority stake in the plant, saw the opportunity to return the area to productive use and develop a solar PV plant. Sonnedix, leveraging its global experience, quickly became involved and was instrumental in the site’s construction and ongoing operation. Sonnedix, as the plant owner, stepped into the leases with the same landowners to restart their cashflow. The Suwa solar plant started commercial operation in December 2017.

Sonnedix has focused on building long-term relationships with the local community and preserving the local environment: During 2018, Sonnedix installed solar roadside lighting and contributed to the rejuvenation of the Zazenso-no-sato Park, a local natural park located adjacent to the solar plant which gets its name from the valuable and rare Zazenso flower, with approximately 1500 people visiting the park each March to see the flower in bloom. The Sonnedix Group provided financial support company to repair a walking trail and pruning trees.

In July 2019, over 70 members of the local community, including 30 children between the ages of 6 and 12 years old, participated in an open day which focused on preservation of the local environment and started with litter collection, followed by a walk to collect rhinoceros beetle larvae and cocoons for the children to nurture. The event culminated with everyone moving on to the solar PV plant site itself, where they spent an hour learning about how the plant works and the benefits of solar power.