Pacific Consultants Co., Ltd. will begin a demonstration project to install floating solar power systems using multiple photovoltaic technologies, including perovskite solar modules, on a dam reservoir in Nagano Prefecture.
The project has been selected under Japan’s Ministry of the Environment’s FY2026 Demonstration Project for Renewable Energy Technologies Utilizing the Spatial Potential of Water Infrastructure.
The demonstration will assess the suitability of floating solar generation on deep dam reservoirs with significant water level fluctuations, while addressing technical challenges related to system design, construction and maintenance.
Pacific Consultants said the project will evaluate the overall system design and construction process, as well as the constructability and maintainability of the solar modules and floating structures. It will also compare the applicability of perovskite, thin-film silicon and conventional crystalline silicon solar modules in the reservoir environment.
The demonstration will be carried out at a water-use dam in Nagano Prefecture.
According to the company, the project is intended to explore the use of water infrastructure spaces for renewable energy generation as Japan works towards its 2050 carbon neutrality target.
If the technology proves suitable for dam reservoirs, Pacific Consultants said it could support wider deployment of floating solar systems at multipurpose dams across Japan, as well as at other underutilised inland and coastal water bodies, including ports and harbours.
The company said it aims to use the findings from the project to develop a renewable energy deployment model for water infrastructure and support the wider implementation of floating solar generation. It added that the project is intended to contribute to decarbonisation efforts while enhancing the value of existing infrastructure.
