A continent-sized sponge—that is what electric vehicles could become for Europe's energy grid, soaking up excess wind and solar power when the sun blazes and the wind whips, then feeding that stored energy back into the system when demand peaks. But a new study warns that weakening the EU's electric car targets would drain that sponge dry, forcing Europeans to build 150 new power plants and spend an extra €4 billion annually just to keep the lights on.
The culprit is a simple physics problem: without millions of EV batteries distributed across roads and parking lots, Europe loses a critical buffer for its renewable energy system. Transport accounts for a vast slice of Europe's emissions, and the EU has set ambitious CO2 targets for car manufacturers to ensure mass adoption of electric vehicles. Yet the automotive industry lobby, ACEA, has demanded those targets be weakened—a move that would result in 49 million fewer EVs on European roads by 2040.
A new study by Fraunhofer ISI for Transport & Environment examined what would actually happen if ACEA got its way. The findings are stark. With fewer EVs, there would be 37% less new solar capacity installed between 2025 and 2040—a loss of 51 gigawatts of solar potential. Renewable energy farms would be forced to disconnect at times of peak generation simply because there wouldn't be enough demand or storage capacity to absorb the excess power. The result: Europe would waste an additional 6 terawatt-hours of clean energy per year by 2040, roughly a quarter more renewable electricity than would otherwise be curtailed.
When peak demand hits and there aren't enough EV batteries feeding power back into the grid, something has to fill the gap. That something, according to the study, is an additional 13 gigawatts of backup capacity—the equivalent of 150 "peaker" power plants, those diesel and gas facilities that fire up when the grid is strained. Building that infrastructure, along with the thicker cables and additional transformers needed to handle heavier loads without local EV discharge capacity, would cost Europeans €4 billion annually in grid upgrades alone.
Geert Decock, electricity and grids manager at Transport & Environment, framed the paradox clearly: "EVs can act like a continent-sized sponge to soak up excess solar and wind energy and feedback into the grid when it's needed. But the car industry's demands to weaken EU electric car targets would result in far less EV battery storage being available. That would change the business case for renewables and suffocate solar deployment."
The economic calculus flips entirely if the EU maintains its current targets. Hitting those standards would allow the bloc to save €27.9 billion per year on fuel costs, more than offsetting the cost of the energy transition. The obstacle isn't physics or economics—it's political will.
There is one caveat: today, most new electric cars sold in Europe cannot talk back to the grid. The EU's Automotive Omnibus legislation should require all new EVs to have compatible, bidirectional onboard chargers from 2032 onwards, ensuring the full potential of vehicle-to-grid technology can be unlocked. Without that mandate, the batteries on wheels remain mostly one-way streets for energy. With it, Europe gains a resilient, cost-effective path toward a fully renewable electricity system. The choice between cheaper coal and gas backup plants or cheaper renewables backed by distributed EV storage belongs not to car manufacturers, but to European policymakers.