As much as 75% of CO2 emissions produced today come from buildings and transport combined. So when a new technology innovation arises which promises to promote energy efficiency and the integration of renewable energy within both sectors simultaneously, it is worth exploring.

Electronics giant Hitachi, along with Mitsubishi Motors and energy firm ENGIE have come together on a new demonstration project to investigate the potential for electric vehicles (EVs) to act as a means of energy storage for an office building. "This demonstration will help provide a new energy solution for energy efficient, low carbon smart buildings. We are aiming to show that EVs and PHEVs (hybrid) can be a vital component of urban energy in the future," said Vincent Cobee, Corporate Vice President at Mitsubishi Motors.

Vehicle to building (V2B) technology is not new. In fact, it has long vowed to play a crucial role in reducing carbon emissions around the world. So what’s “new” about this “energy solution” as Cobee and this consortium suggests?

The status of the firms involved certainly create some excitement. By bringing together respective expertise of Mitsubishi Motors, ENGIE and Hitachi, the consortium believe that an innovative V2B charging station can lead to more intelligent and efficient building energy management systems. For their demonstration project, the alliance linked their first vehicle to everything (V2X) charger to ENGIE’s office building in Zaandam, Netherlands.

ENGIE will connect the battery inside the electric car via a V2X Charger to the building's energy supply system and integrate it with solar panels or other renewable energy sources within the smart grid.

Mitsubishi Motors meanwhile, is providing its Outlander PHEV SUV to act as an energy storage center that building power systems can utilize to access a stable supply of renewable energy.

Hitachi will be providing the crucial V2X charger, which enables bi-directional charging between the electric car battery and the building or electricity grid. It is also supplying the technology which enables the integration of energy between the vehicle and the building, and the vehicle and the electricity grid.

“Hitachi's innovative V2X Charger is the first recharger that cannot only recharge an electric car but can also discharge the energy back into the building/grid providing different flexibilities including kW, ΔkW, kWh and VAR. Moreover, it is possible to connect solar panels and external storage directly to the recharger, allowing a much more efficient electricity supply to buildings,” the consortium states.

So the V2X Charger is connected to the building's energy supply and, when the building generates more solar power than it needs, this excess energy is stored in the battery of the electric car. From there, the energy can then be discharged back into the building or the grid, meaning the car battery acts as an energy storage device, as well as an emergency power supply.

“We reached out to Hitachi and Mitsubishi,” said the folks from smart grid consultancy V2G based in Cornwall, UK. “Hitachi point out that “the PV/Battery inverter functionality is the unique aspect of our charger”, but it’s still not clear to us in what way Hitachi’s claim to offer “the first vehicle to everything (V2X) charger” is justified,” V2G continued.

Things do get a little more interesting in the next stage of the project however. The consortium intends to examine how electric vehicles, renewable energy and Building Energy Management Systems (BEMS) can work together to enable buildings to become energy-neutral. This should lead to a more intelligent and efficient form of microgrid that can interact with BEMS in new ways. Essentially it allows the system to use the available energy in the smartest way possible, thereby minimizing emissions and reducing costs for the building.

“This project demonstrates how our IoT and digital capabilities can help customers make buildings energy-neutral, increasing their energy efficiency and reducing costs, by optimizing EV charging infrastructure. Our technology can also help to create new business cases across the EV value chain, including vehicle to grid technology, which enables flexibility with their energy distribution,” said Ram Ramachander, Chief Digital Officer at Hitachi Europe.

The role of EVs to act as energy storage through a city-wide charging infrastructure must be the ultimate goal. The increasing and expected popularity of EVs will create huge latent storage capacity unless this type of technology can be developed and adopted on a wide-scale. All the elements seem to be falling into place, a 2017 project by the University of Warwick, UK, even demonstrated that such a system that can actually improve performance and longevity of EV batteries.

"This project provides a powerful demonstration of the outstanding effectiveness of energy storage technology,” said Hans Boot, COO at ENGIE Services Netherlands. “This charger exceeds smart charging as we know it and is basically the first real 'smart grid charger'. We hope to begin installing this system for all companies who are eager to take the next step towards becoming truly energy-neutral."

Be it “the first real smart grid charger” or just another attempt to perfect V2X technology, this new project may help us get one step closer to deeply integrating buildings and transport into a futuristic, clean and efficient urban energy system.