When will Europe harness the grid power of mobile batteries as stationary storage?

Batteries are booming and awareness is growing that they are essential for stabilizing renewables-powered grids.

Julian Jansen, vice president of the European Association for Storage of Energy underlines that battery storage is not only useful for grid flexibility by being able to move demand from one part of the day to another, but it also plays a crucial role in “energy security, energy affordability, and sustainable energy supply.” So what role do electric vehicles (EVs) play in stationary storage?

For a start, Europe needs more battery capacity than it currently has. Walburga Hemetsberger, CEO of SolarPower Europe, says stationary battery storage in Europe has grown but it’s still not fast enough. Herbert Diess sees that electric vehicles will play an essential role here. The former CEO of Volkswagen is now CEO of The Mobility House, which specializes in V2G technology so that electric car batteries can be fully utilized.

“The car is only used for an hour [each day],” Diess explained. This means that the high performance automotive battery, that represents the most expensive part of the vehicle, remains unused for most of the time.

Diess maintains that the addition of bidirectional charging capabilities to electric vehicles will mean that grids need less building out because the EV batteries can soak up excess renewable energy when it is most abundant and, with V2G technology, drivers can release energy back into the grid when it is needed.

The Mobility House already has the first 500 customers engaging with V2G and says this has been an “extremely positive” result so far. “Everything works, now we just scale it up,” he says.

Diess points out that the number of V2G-equipped electric cars is increasing, such as the Renault 5 and others, already on the market. These vehicles using their batteries for the grid enables more renewable energy to come online. “The advantages go far beyond the cost-free use of the electric car,” enabling grid providers to save on battery storage as these drivers add their batteries to European grids.

For the drivers engaging with V2G-capable EVs, it means keeping their electric cars plugged in for as long as possible while stationary, ideally for around 10 hours each day, while their charging becomes basically free.

What is missing, he notes, are the relevant standards and regulations so that drivers are paying as much to charge their cars as they can easily recoup by plugging in with V2G capability. Currently in Germany, there is a problem with double taxation that needs to be solved but, generally, all of the technology is available and ready to go. Now it is a matter of activating regulations, business models, partnerships, and collaborations to unleash this capacity.

Chris Heron, secretary-general of E-mobility Europe says, “We have a mountain to climb … to make sure that by 2028, which is when the German government says vehicle-to-grid could be/should be mainstream, we’re ready for that.” European demand for electric cars is rising, he says. “At the start of 2025, we saw 30% sales growth, that’s largely a consequence of European manufacturers implementing their strategies to meeting CO₂ limits that come in place this year, and we have pricing strategies and a wealth of new, affordable models hitting the European market. We’ll have 12 electric car models hitting the market this year for under €25,000 [$28,000].”

Michael Villa, executive director of smartEn explains, “We cannot have 27 different ways for each member state. EVs are no longer only transport assets, these are also decentralized energy resources.”

Hemetsberger said some of the European legislation is already in place. “Germany, Italy, the UK, Austria, and Sweden all have capable market conditions that make sure that there are more batteries being rolled out.”

Jansen says there is a lot to be done in this regard in all European countries, but agrees that a few stand out.

“In Europe, we only have FCR [grid frequency containment reserve] which has a longer activation time so you’re not fully utilizing battery energy storage capabilities to respond enough with 150 ms frequency deviation in that.” Jansen points towards the United Kingdom in this regard, and the creation of a marketplace mechanism to bring in storage to provide stability service like synthetic inertia, synthetic grid-forming capability, and stability voltage control. “If you look at that from the market perspective it gives you the strongest mix,” he says.

Italy stands out too, when it comes to stationary storage, with its Electricity Storage Capacity Procurement Mechanism (in Italian, the Meccanismo di Approvvigionamento di Capacità di Stoccaggio Elettrico: MACSE).

When it comes to Italy, Villa points out here that it really matters what kind of legislation is implemented in order to implement which kind of energy storage facility.

“Italy is definitely … very important and interesting for grid connected storage batteries but it is definitely not an interesting market for vehicle to grid capable vehicles.” He says this is because there is specific state support for stationary storage, “and there is a problem because if we are going to try and integrate as much renewables as possible we need all solutions to target that objective that can compete [with each other] to support that objective.”

Villa emphasizes that EVs are as relevant as grid-scale storage for inter-day generation fluctuation of renewable energy so policy should be also be directed towards bidirectional charging of electric and other opportunities – like flexible demand.”

“Eastern and Southern Europe is getting a good kick start with the European Recovery and Resilience program funds that drive market and regulatory change.” This is, Villa says, because it encourages initial market build up. “To activate new markets for energy storage, those funding mechanisms are really an enabler, and we see that the market frameworks follow, whether that in the Baltics, in Poland, with the creation of frequency markets, and now we’re looking at wholesale ancillary markets in Eastern and south eastern Europe.”

Heron, from E-mobility Europe, summarizes that the field of V2G charging describes a new landscape: “It’s a shared responsibility of vehicle manufacturers, charge point operators, and grid operators to come together and chart that path forwards. By 2027, charge point operators will have to make sure that their installations are compliant and ready for bidirectional charging.” Jansen says, in summary, that from a stationary perspective, “we have to be clear that vehicle to grid has a role to play in the wider battery storage landscape but it does not replace or compete with stationary storage, it’s complimentary and a different framework.”