When storms erupt or the grid fails, EV charging stations need a backup plan to keep the lights on and the power flowing. A process called islanding can help EV charging operations sail through grid disruptions without a hitch.
What Is Islanding?
Islanding is a way to separate a building or complex from the grid during outages. In most cases, these buildings can generate their own power from off-grid resources.
EV charging stations capable of islanding utilize renewable energy sources or battery storage to generate enough power to operate during grid outages. With the right approach, EV charging stations with that capability can mitigate risks and keep people on the road. Here are six ways to use islanding to keep your customers happy and their cars running.
1. First, Mitigate Islanding Risks
While helpful for EV drivers, generating power independently from the grid does have its risks. If, however, the energy the charging station’s power source generates can still flow back into the grid, it can injure utility workers who don’t know that some of the lines are still live.
However, there’s an easy fix: using an inverter fitted with anti-islanding protection. Inverters with anti-islanding features can detect the moment when the grid goes down using voltage and frequency measurements. As soon as it detects the outage, it stops sending power to the grid, protecting workers and first responders from serious injury or death — and your EV charging station from legal liability.
Islanding capabilities without anti-islanding protection can also overload your inverters, causing permanent damage. Having protection is also the law in most places, so it pays to have it.
2. Provide Customers with Non-Stop Service
Islanding-capable backup systems can switch from grid power to backup battery power in mere seconds — nearly in real time. That capability guarantees charging access even during weather emergencies or massive outages.
Most backup systems can integrate a generator if their renewable energy source goes down or their battery runs out of power. If the charging station and its power sources are part of a linked microgrid system, the less affected microgrid could share its power with the more affected one to maintain functionality.
3. Feed Power Back into the Grid for Added Revenue
With a grid-tied inverter equipped with safety protection, you can put its bidirectional charging capabilities to good use even when the grid is up and running. Feeding some of the energy your renewables generate back into the grid during peak usage times can earn extra revenue for your EV charging business. Utility companies pay top dollar for that energy because it keeps the power on for their customers.
4. Maintain Your Complex’s Amenities During Outages
Today’s smart EV charging station owners are adding the same kinds of amenities one finds in gas and diesel stations. Restaurants, restrooms, snack vending machines, and retail stores are all popping up inside fueling complexes to generate revenue and improve customer experience.
When you use an islanding-capable battery electric storage system (BESS) combined with renewable energy sources, it’s not only your charging capability that keeps on going during storm-related outages. The system can also power the buildings housing these amenities, turning them into an island of safety and comfort for drivers who come inside to escape the storm while their vehicles charge.
5. Turn Solar-Powered Fleet Charging Centers into Islanding Microgrids
If you’re a fleet manager whose charging centers use solar power, or a stand-alone EV charging center that charges heavy-duty commercial vehicles, consider turning your facilities into microgrids that can keep the trucks and buses rolling during power outages.
Located on an actual island, a Martha’s Vineyard bus fleet did exactly that, using microgrid controllers to transform its solar-plus-storage charging facilities into microgrids. Solar-plus-storage systems enable drawing power from both battery and solar resources, enabling off-grid capability.
To reduce its dependence on grid power coming from the mainland, the island’s transit authority wanted to transition its bus fleet to a solar-powered electric one, a process that began in 2018. In 2021, the agency began using a solar canopy to charge its new fleet vehicles.
Finally, the bus line installed battery storage with microgrid controllers to create an islanding-capable microgrid. Once that solar-plus-storage system was up and running, it enabled the chargers to keep the buses running even during outages.
6. Create Microgrids to Power Essential Community Services
Setting up a microgrid with your charging stations as a base can do more for your community than providing EV charging services during outages. With renewable power sources, such as wind or solar, plus adequate battery storage, your charging stations can disengage with the local grid and serve as a temporary power source for your community.
Partner with other businesses in your area that have also set up microgrids. Connecting your island-capable microgrids to theirs can provide even more power to your community during storms, cyberattacks, or other disasters.
Black-Start Research
Eventually, these community-wide microgrids might be able to help local utilities jump-start service in their areas through a process called “black-start.” The National Renewable Energy Laboratory (NREL) is conducting research on using microgrids to replace diesel-powered generators to restore power.
The black-start process, as the NREL puts it, is “the ability of generation to restart parts of the power system to recover from a blackout.” It involves various power stations across the area, which start up individually and then gradually reconnect to each other.
Currently, most utilities use batteries to start on-site auxiliary diesel generators, which enables the black-start process. Since island-capable microgrids and other distributed energy resources are growing in popularity as backup power sources, they could become valuable contributors to power restoration during disasters.
Other researchers are exploring how EV charging stations with off-grid power sources can form microgrids and share power. Should the NREL study prove fruitful, having the capability to share power among EV charging stations can make those stations a potent source of energy to assist in black-starts.
Research on EV Charging Stations as Communication Hubs During Islanding Events
Closely related to the black-start studies, a University of Central Florida research project has proposed using EV charging stations as central communication hubs for wireless sensor networks. This is to mitigate transient overvoltages (TOVs) that occur when a distributed energy resource (DER) continues to provide energy to the grid. The wireless sensor networks, combined with the charging stations, could also disconnect the DER from the grid in the process.
If the researchers’ work pans out, it could help solve the problem of some wires remaining live during outages because they’re still receiving energy from DERs, such as solar generators, wind turbines, or backup battery storage.
Instead of actual equipment, the researchers used a simulation to examine the problem. In the simulation, EVs that were connected to the chargers acted as “fast-acting loads for the mitigation of TOVs.”
While many nations have enacted standards to mitigate the risk of TOVs, such as requiring PV inverters to switch off their power supply upon detection of transient overvoltages, there is still potential for failure. In fact, the study shows that there have been several instances of such failures.
For this reason, utilities and DER operators need a fail-safe method to prevent these overvoltages. Quick detection and mitigation are critical to avoid disaster. Communication protocols, too, must transmit data in real time to detect electricity flowing into parts of the grid from a DER.
Power line carrier communication (PLCC) can mitigate transient over-voltages. Installing a transmitter and power switch on the line and a receiver near a PV inverter can be effective. However, the broadcasting equipment required for this type of mitigation comes at a high cost.
Using existing EV charging stations as personal area network (PAN) coordinators, though, won’t incur such a cost. Sensors and actuators along the network can detect and communicate with islanding situations that still feed energy into the grid. EV charging stations have “sufficient processing power, control capabilities, and a direct connection to the EV battery.”
If the connected EVs cannot mitigate the voltage to a safe range, the system will shut down all the network DER inverters, making it a reliable backup plan. If such a system’s real-life performance can equal that of the simulation, this solution will make EV charging stations essential players in keeping people safe and the lights on during storms and other emergency outages.
Learn More About Emerging EV Charging Technologies at the EV Charging Summit
If you’re passionate about emerging technologies and want to learn more about EV charging’s potential as a backup power source and safety valve during outages, you need to reserve a spot at the next EV Charging Summit. With some of the finest minds in EV charging technology presenting their latest discoveries and a wealth of other experts in several EV-related tracks, you’ll go home even more enthusiastic than ever.
Ignite the power of your own EV charging business with the information you’ll gain. Reserve your spot at the Summit today!
