Nestled in the hills surrounding the verdant agricultural plains of Kunitomi - literally "beautiful place" - the ¥100bn ($1.2bn) plant, capable of producing 900MW of thin-film modules a year, is the result of over three decades of research and development by parent company Showa Shell Sekiyu.

Spanning three storeys in a 158,000-square-metre building, Solar Frontier's highly automated operations are vast by any standards.