Photo/IllutrationSolar power is all the rage in this residential area in Saitama Prefecture. (Asahi Shimbun file photo)

It's not just utilities that are power hungry.

All sorts of business opportunities are opening up to lure power-generating households to part with their electricity.

This is due to a soon-to-expire government program that obliges utilities to purchase surplus electricity from private homes at fixed prices under a feed-in tariff system to promote clean energy.

Some companies are offering to purchase surplus household solar power, while others are introducing battery systems that allow the energy to be stored for later use.

With the feed-in tariff program winding down from 2019, housing development and other enterprises, eager to pick up the slack, are racing to purchase the energy resource.

Electronics manufacturers and other entities are also vying for a slice of the pie with devices that allow households to make efficient use of surplus electricity.

Under the feed-in tariff system, utilities are obligated to purchase solar power from private homes at fixed rates over 10 years.

While 350,000 households signed electricity trade contracts with utilities when the predecessor of the renewable energy purchase mechanism was initiated, their contracts will expire in November 2019, according to the economy ministry.

The households have a combined power production capacity of 1.35 gigawatts, a level comparable to that of a large nuclear reactor.

As utilities will not need to purchase home-generated electricity at higher rates after the contracts expire, households are expected to switch to providing their surplus power to other types of companies or store it for later consumption.

Housing developer Sekisui House Ltd. saw this as too good an opportunity to miss out on. It intends to purchase surplus solar power from private homes not covered by the feed-in tariff system to eventually meet its goal of covering its own power needs with renewable energy.

Homes sold by the company that are equipped with power generators will be able to sell their surplus electricity to Sekisui House at 1 to 2 yen higher than the per kilowatt-hour wholesale rate.

Sekisui House’s purchase price will be lower than power utilities’ fixed rates under the feed-in tariff system. Households that concluded contracts in fiscal 2009 can, for example, sell their surplus power at 42 yen per kilowatt-hour.

Manufacturers of storage batteries, as well as electronics companies, predict that households will increasingly reply on home-produced power. These entities are moving to grab a slice of this emerging market.

For example, Toshiba Lighting & Technology Corp. began marketing the eneGoon smaller battery system for home use in July last year. The 7.4-kilowatt-hour battery is sufficient to power a refrigerator, lighting, TV and other basic home appliances for 14 hours straight.

Electronics parts maker Omron Corp. began selling a home-use battery system last October that can be installed even after a house is built.

A new entry to the power business, Tokyo-based Looop Inc., introduced a service last September to allow customers who purchased its special storage cell to buy electricity at 3 yen cheaper that the ordinary per kilowatt-hour rate.

The company is hoping to appeal to households whose fixed price purchase contracts have expired.


A lot is riding on whether companies divulge details of customers selling power through feed-in tariff contracts.

If they don't, it will be difficult for other companies to win over new consumers, experts say.