The first thing you notice about the WattStation by GE, this magazine’s sponsor, is the striking design: a brushed-metal cylinder rises from the pavement and is capped by a circular touch-screen that welcomes you with a “Hello.”
But beneath the fetching exterior – crafted by industrial designer Yves Behar, creator of the Jawbone phone headset – lies a tool capable of not only charging electric vehicles rapidly, but also communicating with your car, your home, your smartphone and the smart grid.
You can expect to see WattStations on public streets soon. So how do they work?
Ease your car up beside a WattStation with a glowing green ring around the face, which signifies that it’s ready to charge.
Press the touchscreen, which will then prompt you through the steps. (If you’re at a private charging station, you may need to wave a radio frequency identification card, or RFID, provided by the station’s owner, to gain access.) You can input your phone number or email address so the machine will ping you when the charge is complete.
Then, remove the connector from the station and plug it into your car. The ring will glow blue to indicate the station is in use.
Once the charging begins, you’re done until it’s complete. “You don’t need to stand next to it and babysit it,” says Daniel Ciarcia, EV product manager at GE.
The WattStation home charging system, which can sit on the wall of your garage, is even simpler. Just plug it in and go.
A handshake, then a negotiation
When an EV is first plugged into a WattStation, the two devices recognize each other through the five-pin connector that fits all standard electric vehicles.
“It’s a handshake to say, ‘I am an electric vehicle,’” Ciarcia says. “The vehicle says, ‘I’d like X number of amps.’” The WattStation either accepts or negotiates a different standard of power and then begins the charge.
The WattStation accesses the grid’s power through a secure connection in the ground. The power moves through a “contactor,” which opens and closes to energize the connector. Fuses and ground fault monitoring ensure the device delivers reliable and safe power, Ciarcia says.
The WattStation is a Level 2 charger, which means the power delivered to the car is 208-240 volt AC at 30 amps with a maximum output of more than four times that of a Level 1 charger – essentially, a 110V household wall outlet. It can provide a full charge in four to eight hours, compared with 12 to 18 hours at standard outlets.
Communication is key
The WattStation communicates with your car and your phone, but it can also talk to the smart grid, if the function is enabled, through advanced metering infrastructure, or AMI.
For example, if the grid is close to capacity and needs to shed some power load, it notifies the WattStation, which then responds by reducing its charging level.
WattStation owners – for example, a city authority – can also receive data from their units to track usage and access.
The EV-charging market is expected to grow rapidly in the coming years. Research indicates that there will be a demand of 1.4 charging stations for every EV sold and GE wants to make the WattStation the charger of choice.
“The goal was creating a very pleasant experience for the drivers,” Ciarcia says.