The New Volvo EX90 EV SUV's Bidirectional EV Charger Explained
To truly be green, EVs must be able to store surplus power by day, then share it with the grid during peak consumption hours.
All the cool greenies have one, and so must the 2024 Volvo EX90. The bidirectional EV charger is this season's must-have green gizmo. Big-battery EVs draw heavy fire for the ethical and environmental impacts of mining their materials and the amount of CO2 expended in battery production, not to mention worries about overloading an aging, overtaxed power grid that may still rely a bit too heavily on coal. One sure-fire way to reframe the narrative is to allow your big-battery EV to share its energy back to the grid, allowing it to suck up green power while the sun shines or the wind blows, then give it back when demand peaks. Then it can be a savior of both the beleaguered power grid and your family when the power goes out. Remember the glowing headlines all those Ford F-150 PowerBoost hybrids made during that winter blackout in Texas last year?
What is a Bidirectional EV Charger?
Quite simply, it's the ability for power to flow back out from the EV's battery, through the charge port, to a specially designed bi-directional charger. The vehicle hardware and software needs to support power export—as opposed to import, in which it simply charges itself—and to date most bi-directional charging has required a DC connection, which was provided on many CHAdeMO connectors, which is why the Nissan Leaf and Mitsubishi Outlander PHEV were first to offer this feature. The Ford F-150 Lightning utilizes the lower-two DC fast-charging pins on its CCS plug to export power.
Outside of the car, the wall-box needs additional hardware to convert DC back to AC home power. And the whole thing requires communication, typically via cloud, to authorize power flow from the vehicle to the charger.
Here are Four Ways to Export Power:
- V2L: Vehicle-to-load. This one's easiest. Volvo envisions providing an adapter that plugs into the EX90's charging port, that simply has an AC power outlet designed for the voltage and configuration of the market. That adapter will communicate via the CCS port that AC power is being used, specifying a current-draw limit (which Volvo has yet to disclose). Hyundai and Kia currently offer such a V2L plug for the EV6 and Ioniq 5 EV crossovers.
- V2V: Volvo-to-Volvo. The EX90 will offer an accessory cord with CCS plugs on both ends that allows EX90 owners to buddy-charge another Volvo (without using the DC plugs). To start, the communications link through the cable limit charging capability to other Volvos only, but this could be expanded in the future.
- V2H: Vehicle-to-Home. The installation of any bi-directional EV charger (or home solar, or hard-wired backup generator) must include a grid isolator, to prevent harming workers repairing a power line. Then with a smart-charging app (a prerequisite for bi-directional charging), owners can direct their EV to charge when grid pricing is lowest or green energy production is highest; then ask the car to power the home when demand or power-pricing is highest.
- V2G: Vehicle-to-Grid. Arranging for an EV to share power with the grid requires another layer of buy-in from the local utility, which can then take control of that grid isolator and allow your power meter to "spin backwards," presumably paying you something for the privilege.
How Does Volvo's Bidirectional EV Charger Compare?
Good question! At this point Volvo isn't divulging many specifics, or even confirming that North America will get this feature at the time of the 2024 Volvo EX90's launch in the second half of 2023. We don't know the wallbox supplier, whether the company has partnered with any power companies, or even the peak power export rate for any of the four charging scenarios above. We do know the company plans to be competitive, and for its bidirectional charging systems to be compatible with (or somehow connectable to) similar systems in the market today that may also include battery backup storage systems.
What Will Bidirectional Charging Cost?
The onboard capability for bidirectional charging will come standard on the EX90 and we're assured the wall-box will be priced competitively. Ford charges $1,310 for the F-150 Lightning's 80-amp Charge Station Pro unit, or about triple the rate of a one-way charger. Of course that does not include installation, which may also cost more if there's not already a grid isolator in the home.