Panasonic, which leads Japan’s market for standard EV chargers and solar panels, starts sales of its vehicle-to-home (V2H) system in February. It will market the product through 5,000 business partners from electrical contractors to homebuilders.
V2H systems include two-way chargers, which let electricity flow both into and out of batteries, as well as power conditioners that turn direct current from batteries into alternating current for use inside homes.
EVs have been slower to catch on in Japan than in the US or Europe. But homeowners who are likely to use V2H technology already have solar panels and storage batteries at home, Panasonic said.
Adding an EV into the mix lets customers consume more – around 90% – of the electricity produced by their solar panels, reducing the need for purchases from the grid at a time when power prices are soaring.
Electronics manufacturer Omron brings its V2H system to market in May. The company, best known for medical devices, designed the system to weigh 25 kg so it can be installed by a single worker.
Sharp plans to enter the V2H market within a few years as well.
The V2H market is in its infancy worldwide, and widespread adoption will require standardisation of charging and discharging technology. Tesla vehicles are not considered compatible with V2H at this time.
Japan’s slow adoption of electric vehicles led Mitsubishi Electric to exit the V2H space in 2021. But EV sales in the country are rising, hitting a record 17,771 – or 1% of new vehicle sales – in the first half of 2022.
Two-way EV chargers alone usually cost over ¥1 million (US$7,600) in Japan. Subsidies cover up to half of their cost, to a cap of ¥750,000. V2H systems involve even more components. But interest in their ability to promote the use of renewable energy has grown as electricity prices soar in Japan.
Nichicon, mainly known for producing industrial capacitors, is investing around 2 billion yen to enlarge its Kameoka factory in Kyoto prefecture for V2H systems and home batteries. It aims to open the wing in 2023.
The company this year also aims to double production capacity of two-way chargers for V2H systems, currently around 1,000 units a month.
Nichicon said it controls around 90% of Japan’s V2H market, which it entered in 2012. It has partnered with overseas automakers like Mercedes-Benz.
“Our order backlog is continuing to grow,” Chairman Ippei Takeda said, partly due to supply chain disruptions caused by the coronavirus.
Asked whether frequent V2H charging and discharging could wear EV batteries down faster, a representative at one V2H tech maker said: “There is some effect, but we believe it is negligible given how durable the batteries are.”
V2H does not cause any problems in terms of degrading batteries, a representative at an automaker said.
V2H systems can serve as an emergency power source during natural disasters. Nissan Motor’s top-end Leaf EV carries a 60 kilowatt-hour (kWh) battery – as much power as a typical family uses in four days. Its Sakura mini electric vehicle comes with a 20 kWh battery, still larger than the typical home battery in the 5 to 10 kWh range.
V2H system makers say expanding will present a challenge given the lack of universal standards.
“No clear standards have emerged for charging and discharging batteries,” Takeda said. “We want to be involved in the rule-setting process.”