The industry ministry is contemplating promoting the use of perovskite solar cells to cover 20 gigawatts of electricity — the equivalent of 20 nuclear reactors — in 2040, officials said.

The plan is part of work to expand the use of renewable energy sources by supporting the introduction of next-generation technologies as the country is racing to reduce carbon emissions.

The ministry aims to include the plan in the country's basic energy program that the government will update within fiscal 2024, which ends next March.

The existing energy program calls for increasing the proportion of renewable energy sources to 36% to 38% of power generation in fiscal 2030, compared with 22.9% in fiscal 2023.

The new program, which sets goals for fiscal 2040, is expected to further raise the renewable energy share in anticipation of the spread of perovskite solar cells.

Perovskite solar cells, which are thin, light and flexible, can be installed anywhere, such as on the wall of a building. As they are more expensive than conventional solar cells, the ministry will subsidize part of the costs for the time being starting in fiscal 2025.

Companies are moving to develop perovskite solar cells as a promising technology for expanding the use of renewable energy sources.

Sekisui Chemical is set to commercialize such cells in 2025, with plans to install them in high-rise buildings in Tokyo with Tokyo Electric Power Company Holdings and others.