Solar power in Japan

Solar power in Japan has been expanding since the late 1990s. Japan is a large installer of domestic PV systems, with most of them grid connected.^[1] The country was a major manufacturer and exporter of photovoltaics (PV), with a global market share of around 50% in the early 2000s. However, by 2019, this had dropped to below 1% due to the rise of state-backed production in China.^[2]

With almost no domestic oil and gas reserves, Japan began investing heavily in research and development of renewable energy and energy conservation following the 1973 oil crisis. The Sunshine Project (1973–1992) explored the potential of solar power, geothermal power, liquefied coal, and hydrogen as primary energy sources. In 1992, during the early years of commercial PV installation, Japan accounted for 27.8% of global PV production, and by 2004, this had risen to 50.4%. Although conventional PV is no longer mass-produced in the country, Japan has been investing in perovskite solar cell technology in recent years, a technology invented by Tsutomu Miyasaka. Commercial production of perovskite cells in Japan is expected to begin by 2027.^[2]

Solar power has become an important national priority since the country's shift in policies toward renewable energy after the Fukushima nuclear accident in 2011.^[3][4] Japan was the world's second largest market for solar PV growth in 2013 and 2014, adding a record 6.97 GW and 9.74 GW of nominal nameplate capacity, respectively. By the end of 2017, cumulative capacity reached 50 GW, the world's second largest solar PV installed capacity, behind China.^[5][6] In line with the significant rise in installations and capacity, solar power accounted for 9.9% of Japan's national electricity generation in 2022, up from 0.3% in 2010.^[7]