Smart energy: Why vehicle-to-grid technology is on the move

There’s a lot to be said for using car batteries as temporary energy storage facilities, but significant barriers still stand in the way of widespread uptake, as Jessica Twentyman explains.

What do you get if you cross an electric vehicle with a smart building? According to Hitachi Europe, Mitsubishi Motors, and energy company ENGIE, the answer could be an energy-neutral office block that uses cars in the parking lot as a temporary energy storage facility.

Last week, the three companies announced a project in the Netherlands that will see them test out their theories, by linking a Mitsubishi Outlander plug-in hybrid electric vehicle (PHEV) to ENGIE’s office building in Zaandam, via Hitachi’s two-way V2X Charger.

The V2X Charter can be used not only to recharge an electric vehicle (EV), but also to discharge the energy held in its battery back into a building when needed. In this way, when a building equipped with solar panels generates more energy than it needs, for example, the excess might be stored in vehicles until it’s required.

For the next stage of its project, the consortium will examine how EVs, renewable energy, and smart building energy management systems might be more closely coordinated to reduce energy costs and emissions, with the ultimate goal of making buildings energy neutral, according to Hitachi Europe’s chief digital officer, Ram Ramachander.

“Our technology can also help to create new business cases across the EV value chain,” he says, “including vehicle-to-grid technology, which enables flexibility with their energy distribution.”

V2G promises

The term ‘vehicle-to-grid’, or V2G, is not new. The idea of using car batteries as a source of power in grid services has been seen as attractive for several years, not only because of the growing lithium-ion capacity tied up in EVs, but also because much of that energy is not being used a great deal of the time.

As Vincent Cobee, corporate vice president at Mitsubishi Motors, puts it, the project in Zaandam aims to show that EVs and PHEVs “can be a vital component of energy in the future.”

Last month, automaker Nissan announced a partnership with energy giant E.ON at the Geneva Motor Show, which focuses in part on “vehicle-to-grid infrastructure and advanced bi-directional charging technology to allow customers to optimise their energy use and costs.”

The UK government seems to see a lot of promise in V2G, too. In February 2018, the Department of Transport announced a new £30 million investment in V2G technologies, which it hopes will unlock the potential for EVs to be used to power homes, rather than the other way around.

Transport Minister Jesse Norman certainly didn’t hold back his enthusiasm for the technology. “These projects are at the cutting edge of their field,” he said. “Just like the visionary designs of Brunel and Stephenson in transport, they could revolutionise the ways in which we store and manage electricity, both now and in the future.”

One of the groups that will benefit from that funding brings together energy storage specialist Moixa Energy, the UK’s National Grid, Western Power Distribution, and Nissan’s Technical Centre Europe, among others.

If electric vehicles are left plugged into smart, two-way charging points when not in use, argue the consortium’s members, their batteries can feed power into the network at times of peak demand. Just ten new Nissan LEAFs can store as much energy as a thousand homes typically consume in an hour, they claim.

“Smart chargers can also control when cars recharge to avoid stressing the network and to store surplus power when demand is low. This will allow the grid to operate more efficiently, support high levels of renewables, and rely less on fossil fuel power stations,” the consortium says.

Its study, V2GB – Vehicle to Grid Britain, aims to establish the best way to incentivise a rapid rollout of the technology, via sharing the revenues that result from V2G energy flows among drivers, owners of smart charging stations and car parks, and aggregators of battery capacity.

Internet of Business says

A promising technology, but the journey to becoming a mainstream, everyday option is still some way off for V2G. One concern it that discharging energy from a stationary EV stresses its battery, which is one of its most expensive components.

Paying drivers to take part may prove to be the critical incentive that helps V2G schemes succeed, but not all drivers will be persuaded to participate, especially if they’re concerned about their EV being drained of power just before they set off on a journey. This is where smart energy management software may play a big role, by helping to ensure that charging and discharging fits in with drivers’ preferences and schedules.

Utilities’ ability to keep up is also in question. It’s no secret that many are already struggling to deal with growing EV charging requirements, even though they look set to gain massively if they can reposition themselves as ‘the new petroleum companies’.

Recent analysis by research firm Wood Mackenzie, for example, predicts that simultaneously charging 60,000 EVs in Texas could cause a massive grid failure in that state – even though that total accounts for just 0.25 percent of the 24 million vehicles registered by the Texas Department of Motor Vehicles.

Plus, there just aren’t that many EVs available that support two-way flows. Most EVs can chug away at charging points, but vehicles capable of regurgitating the contents of their battery for use elsewhere are yet to emerge in substantial numbers.

In short, automakers have a lot of work to do to make V2G systems work.

But that is not to say that the hurdles can’t be overcome in time. The benefits are potentially huge: a more resilient smart grid, energy-neutral buildings, cleaner air, and lower carbon emissions.