EVs are more than just a cleaner transportation alternative. With V2G technology, they can become key players in the energy transition, benefiting both the electricity system and EV users. But technical hurdles and regulatory challenges are slowing widespread adoption. 

 By Lisa Calearo, Senior R&D Engineer at Spirii  

Increasing EV adoption is a critical step in tackling climate change, yet it poses serious challenges for the power grid. 

But what if EVs could actually help solve the problem? 

EVs can already help stabilise the grid by adjusting their charging power. With vehicle-to-grid (V2G) technology, this potential goes even further, allowing them not only to draw power from the grid but also to feed energy back into it. 

Turning EVs into profitable energy assets  

Current EVs hold significant energy potential, with batteries ranging from 50 to 100 kWh in passenger cars and up to 500 to 700 kWh in heavy-duty vehicles. Even accessing a small portion of this capacity could offer major benefits to the electricity system. 

V2G technology allows EVs to act as both load and generator: when energy production exceeds demand, such as during periods of strong wind, EVs can charge and absorb surplus electricity; conversely, when demand is higher than supply, they can discharge energy back into the grid. 

On a local level, V2G can improve energy resilience. In Japan, where earthquakes frequently disrupt the power grid, bidirectional charging has been considered as a backup solution since 2012. 

For V2G to succeed, it must deliver clear value to EV owners. Imagine a fleet depot where hundreds of EVs are parked overnight. V2G technology would enable fleet operators to sell power back to the grid during peak demand and recharge at lower, off-peak rates. This could create an additional revenue stream, ultimately reducing the total cost of ownership (TCO). 

Compelling, right? So, are we all set to plug in and cash out? Unfortunately, not yet. 

Regulatory and technical roadblocks 

The core technology already exists. Households can install batteries to store solar energy, use it in the evening, or sell it back to the grid. 

So why is it more complicated with EVs? 

The key difference is mobility. EV batteries, often five times the size of home batteries, connect to various parts of the grid. This makes it harder to ensure smooth, standardised interaction between vehicles, chargers, and grid operators. 

Currently, automakers, energy providers, and regulators are not fully aligned, resulting in inconsistent technical standards and fragmented deployment. 

One of the biggest barriers is the lack of standardised infrastructure that supports bidirectional charging across EVs, hardware, and software. 

While the industry recognises the potential of V2G, regulatory frameworks have to adapt to facilitate EVs to feed energy back into the grid in an easy and profitable manner.  

To make V2G viable at scale, we need new pricing models that fairly reward EV owners for contributing to grid stability and make participation financially worthwhile. 

Scaling up V2G through collaboration 

Despite these technical and regulatory barriers, V2G is becoming a reality. It is already being tested with various EU pilot projects, marking an important step forward, but broader deployment requires greater regulatory and infrastructural alignment. 

At Spirii, we are actively maturing V2G technology through EU research and development projects. 

Notable examples include the FLOW project, which explores user-focused and interoperable solutions to enhance V2G opportunities, and the AHEAD project, which investigates the cybersecurity challenges associated with implementing V2G.  

Ultimately, V2G technology will only reach its full potential when we achieve the right combination of advanced charging infrastructure, standardized protocols, and financial incentives for consumers. 

For this to happen, governments and industries must collaborate to create policies that encourage this transition and allow the technology to scale, empowering both the EV owners and the electrical grid.