New Zealand vehicle-to-house trial allows EV batteries to power appliances in the home

A Mitsubishi PHEV in a drive
There are still limitations, including cost and regulatory approval, to be overcome. Photo credit: Supplied / Mitsubishi

Kiwis with electric vehicles (EVs) may soon be able to use the battery from their car to help power their homes, with the technology close to becoming more widespread, according to Mitsubishi Motors NZ (MMNZ).

In June, the company became the first in New Zealand to install and operate a V2H (vehicle-to-house) unit, which allows electricity stored in an EV's battery to be supplied into a building's power network. 

By installing the module, MMNZ is able to use solar panels to charge its fleet of Plug-in Hybrid EVs (PHEVs) and then use that solar-generated charge in the PHEV batteries to power electric hoists and other appliances. 

MMNZ's technical services manager Lloyd Robinson says the company has been keeping a close eye on the development of this cutting-edge technology for some time and has been encouraging its Japanese parent to fast-track V2H in its cars. 

"We have been aware that V2H modules would eventually land here and so have been able to ensure that all of our current generation Outlander and Eclipse Cross PHEVs, and our previous generation Outlander PHEVs, with CHAdeMO DC fast charge connections are V2H ready," said Robinson. 

While still in its infancy for NZ, the technology has the potential to provide stored energy resilience to New Zealand's power grid, by helping to buffer peak demand, MMNZ said.

Depending on the model, a Mitsubishi Outlander PHEV battery has a total power capacity of up to 20kWh, about the daily power consumption of an average Kiwi household with two adults and two children, according to 2018 figures from the Government.

However the V2H modules can only be connected to properties with 3-phase power networks and can only be active during normal operation of the power grid, meaning they're still limited in scope.  

"The system can't currently be used during a power outage because there is no foolproof way to ensure the power from the battery doesn't flow back into the grid and place electrical workers in danger," said Robinson.

"However, those types of hurdles will be overcome as uptake of the technology grows. 

"V2H is a really exciting development. And, while there are still some regulatory considerations to be worked through, I think we'll start to see consumers looking at their cars in a whole new way." 

One of the other downsides is the units are still relatively expensive, but are expected to come down as demand grows, Robinson said.

In the meantime, late model Mitsubishi PHEV owners who have properties or businesses with 3-phase power and who charge their vehicles on night rates or via an alternative generation source can now store that cheap power in their vehicle's battery and pass it back into their premises when electricity prices are higher.