Europe’s electric vehicle boom is colliding with an electricity grid under growing pressure from electrification and renewable variability. In the long run, millions of parked EVs could become the distributed storage backbone of Europe’s energy system. But bidirectional charging will scale only with scientific progress, market readiness and public engagement is effective — and a survey confirms it: the human factor will be decisive.

During AFC Ajax match days at the Amsterdam Johan Cruijff ArenA, the spectacle is not confined to the pitch. As tens of thousands of fans stream into the stadium, long rows of electric vehicles remain parked outside, quietly storing solar energy collected over the afternoon and later feeding part of it back to the stadium when demand surges. A scene that would have sounded futuristic only a few years ago is now technically feasible, and researchers developing advanced charging systems say the foundations are already there. As Professor Gautham Ram Chandra Mouli of TU Delft explains, this scenario illustrates a broader point emerging from advanced charging research: “An electric vehicle is not just a load but a potential micro–storage unit, capable of supporting the grid when managed through precise modelling and controlled charging.” In his view, “mobility and energy are no longer separate systems: if managed correctly, the EV becomes part of the energy infrastructure.” The timing is relevant: according to the European Automobile Manufacturers’ Association (ACEA), in 2025, battery electric vehicles accounted for around 16% of new-car registrations in the EU, reflecting strong growth in EV uptake. This growth overlaps with a grid increasingly strained by electrification, local congestion and renewable variability. As highlighted in the IEA’s World Energy Outlook 2023, Europe faces more than €3.5 trillion in required grid investments by 2035 to modernise and digitalise its electricity networks. In this context, turning EVs into distributed storage is not a futuristic idea but one of the most realistic forms of flexibility available at scale. As Mouli adds, the logic is simple: “The vehicles are already there, already plugged in, already carrying large batteries.”

Yet today’s EV ecosystem has a core limitation: most vehicles can receive energy but not return it to the grid. Many models technically could, but this function is deactivated due to uncertainty. “Battery lifetime, thermal behaviour and charging dynamics must be modelled precisely before exposing users to additional cycles,” Mouli notes. Automakers remain cautious because ageing mechanisms vary widely across chemistries and thermal systems, and warranties must be built around predictable patterns. From the grid operator’s perspective, the challenge is scale. Luiz Dias of EDP NEW, a DriVe2X project partner, summarises it clearly: “To unlock flexibility at the scale Europe needs, vehicles must become two-way devices — not just consumers of electricity but contributors to local stability.” The long-term vision is neighbourhoods, workplaces and mobility hubs where EVs provide electricity when demand spikes and absorb excess when renewables surge. This intersection of technology, infrastructure and user behaviour is exactly what DriVe2X is testing across several European cities. Solutions that perform well in simulations are being validated in open, real-life environments to see how EVs behave under daily constraints. Beyond the ArenA, tests in Budapest are taking place in private homes where charging routines interact with rooftop solar generation and tariff optimisation. At Porto Airport, vehicles remain plugged in for long stays, offering insight into predictable charging patterns and user satisfaction. In Maia, northern Portugal, vehicle-to-everything (V2X) is being added to a dense network of charging points. The project also explores tourism-driven charging behaviour on the Isle of Wight in the UK, where EVs remain parked for extended periods, and the ASM living lab in Terni, Italy, where blockchain-enabled energy transactions are complementing incentives for smart and bidirectional charging.

The demonstrations show that bidirectional charging works best when users trust the system. This trust depends on infrastructure availability, clear information and the certainty that the car will always be ready. As Dias notes, “We face challenges in each of these dimensions, but two are particularly present: the lack of vehicles truly compatible with bidirectionality and the need to design operations that are as open to the public as possible.” At the technical level, research within DriVe2X indicates how advanced modelling can reduce battery stress. Mouli’s team integrates empirical and physics-based ageing models to simulate how different lithium-ion chemistries react under bidirectional cycles. “We model applications, battery types and thermal behaviour together,” he explains, “so we can predict ageing accurately and ensure V2G does not compromise user needs.” Their work suggests that, when managed carefully, V2G can even reduce certain forms of degradation by keeping batteries at moderate charge levels rather than fully charged for long periods — an insight that challenges the common fear that bidirectional charging necessarily accelerates ageing.

But the most decisive element in transforming cars into active energy resources is the human factor. A large-scale survey was designed to understand how people think about, use and emotionally relate to EV charging. It captures technical preferences as well as cultural habits, socioeconomic conditions and behavioural patterns that will shape electrified societies. “One of the clearest barriers emerging is a persistent lack of clarity,” explains Carlos Montalvo, Senior Scientist on Strategy and Innovation Policy at TNO. “People don’t really know how the battery will behave in the long run, how much they could earn, or who is responsible if something goes wrong. This makes the survey a mirror of a changing society.” The paradox is that several EVs already have the technical capacity for V2X, yet the function remains disabled because responsibilities and warranties are not standardised. Montalvo highlights how striking the survey results were: “Beyond cost and convenience, emotion emerged as one of the strongest predictors of willingness to engage in V2X: feelings of pride, usefulness and contribution to the common good correlate strongly with acceptance.” Participants who already own solar panels, home batteries or efficient heating systems “are far more inclined to try V2X because they already understand energy flows and see the vehicle as part of a broader household ecosystem.”

After mapping these emotional, behavioural and informational patterns, the implications become clear: bidirectional charging will scale only if technology and infrastructure evolve alongside people’s expectations, habits and uncertainties. The scene at the Amsterdam ArenA offers a glimpse of what this transition could look like: in the long term, millions of EVs — which spend 92% of their time parked — could become the distributed storage backbone of Europe’s energy system. Its deployment will depend on scientific progress, market readiness and public acceptance. As Mouli notes, “There is still a lot to be done, from battery lifetime to uniform grid codes, but once these challenges are addressed, mass adoption becomes possible.” Dias agrees: “The experience must be smooth, practically intuitive. Smart charging should be the default — with ‘dumb’ charging as the last resort.” What ultimately determines adoption, Montalvo concludes, is “whether citizens feel that V2X is safe, fair, understandable and compatible with daily life.”

Article by Martino de Mori