If every consumer vehicle on the planet were electric last year, the total energy consumption worldwide would have been 13% higher than the previous year. As Electric Vehicles (EVs) drastically increase energy drawn from the electric grid and contradict sustainability efforts, the importance of Vehicle-to-Grid (V2G) charging solutions cannot be understated. Because it's still a relatively new technology, this resource will explain how V2G works.
What Is V2G?
V2G is a bidirectional charging technology available to electric vehicle owners. This allows Distributed Energy Resources (DERs) like vehicle batteries to receive and send energy back to the electric grid. As a result, grid operators are better positioned to handle peak load demand periods. Moreover, a vehicle can be transformed into a charging station to power a home and appliances.
V2G solutions are best for EV drivers or commercial fleets that don’t travel too many miles and are often parked during the day. This ensures that the battery’s State of Charge (SoC) is consistently high. In return for sharing energy from their electric vehicle, users are rewarded with monetary benefits.
How Does V2G Work?
First, the V2G process involves the electric grid sending signals to available vehicles about dynamic energy needs in the area. Then, based on the signal, the energy management system automatically adjusts charge and discharge rates.
Excess energy, including renewable sources (e.g., wind and solar), is temporarily stored in the EV battery. When there is demand, the power will be sent back to the grid for consumption. For utility providers, the EV charging technology helps keep load capacity sufficient, even when demand is volatile.
V2G technology is also essential for capturing intermittent renewable energy sources. The sun is less intense during peak energy demand from 6 p.m. to 8 p.m. But a V2G-supported EV with energy storage capabilities can capture solar energy from earlier in the day and reallocate it to the grid later. Similarly, if the wind isn’t blowing, EVs can send the solar power it previously stored back to the grid.
Figure 5: How V2G Works
Requirements for V2G to Work
Although V2G supports the electric grid effectively and sustainably, it’s also the most challenging form of bidirectional electric charging to incorporate into the consumer space.
For starters, the EV owner needs to possess an advanced separated bidirectional converter to enable the connection to the grid. In addition to compatible hardware, V2G solutions require smart grid infrastructure, energy management platforms, a contract between users and the utility company, and user consent to allow energy suppliers to access their devices.
On top of that, V2G charging technology necessitates platforms that meet the regulatory criteria. Assuming that a user knows when the vehicle will be unplugged and how full they want the battery to be, a cloud-based smart charging platform ensures that an EV is always charged when energy must be drawn from it. This makes aggregators, such as Nuvve and Kaluza, key partners serving as a “central hub” for DERs interacting with the grid.
Why V2G Works Better for Commercial EVs
For V2G to work within the consumer segment, you would need around 5,000 vehicles to make a meaningful contribution to the electric grid. This is because consumer EV batteries have significantly lower storage capacity than large commercial vehicle batteries.
For this reason, in combination with range anxiety, V2G solutions have been more popular among commercial fleets, notably school buses. Not only is there an apparent Return on Investment (ROI) for commercial users, but school buses, refuse trucks, and commercial delivery fleets meet the right conditions required for V2G to work optimally, such as the following:
- Habitual time and route-based schedule with predictable energy needs.
- Batteries are constantly charged and ready to store or provide energy back to the grid because the vehicles sit idle most of the day.
- Larger batteries found inside these vehicles can store a substantial amount of energy. Compared to the 7 Kilowatts (kW) of power capacity found in private cars, a school bus can hold 60 kW to 125 kW of power, according to Nuvve.
School buses, in particular, are ideal for V2G considering the entire fleet is back at the warehouse and hooked up to the electric grid during peak demand periods.
The chart below forecasts the number of vehicles that will ship with V2G technology between 2022 and 2027 globally.
Learn More about V2G and Other EV Charging Technologies
As the world transitions to clean energy, municipalities worldwide must understand the crucial role that V2G will play once the EV installed base increases. Without V2G technology, electric grids will continue to be unsustainable.
To learn more about the role of V2G and other EV charging solutions in supporting the electric grid, read our Electric Vehicle Smart Charging: Preventing the Dreaded Grid Blackout Research Highlight.