Photo/IllutrationSolar panels installed on the roofs in a residential area of Saitama Prefecture (Asahi Shimbun file photo)

Have extra solar power at home? You may soon be able to sell it to other households.

Kansai Electric Power Co. said last month that it has started a study with the University of Tokyo, MUFG Bank and Nihon Unisys Ltd. on a system that will allow transactions among individuals.

The peer-to-peer (P2P) energy trading technology would provide an alternative for households currently selling solar power under a government program, which requires utilities to purchase it at a premium for 10 years.

The program was introduced in 2009 to promote renewable energy. The purchase price guarantee will be phased out from next year.

Kansai Electric will continue the study until March and plans to move on to an experiment involving households.

In the study, households buying solar power generated at other homes would pay in virtual currency.

Data on transactions, such as electricity volume and prices, would be recorded with “blockchain,” a technology used as a public ledger for cryptocurrency trading.

In November 2019, the 10-year purchase price guarantee will end for about 380,000 households that concluded a contract when the surplus power purchase program started.

The solar panels installed at those homes have a combined power generation capacity of 1.4 gigawatts, equivalent to more than a typical nuclear power reactor.