How charging electric vehicles helps create a stable electricity grid

Building a flexible energy system

The energy system of the future must be flexible. Renewable energy from solar and wind is not always available, which means we need smart solutions to balance supply and demand. Today, fossil-fuelled power plants still fill the gaps — but if we want to reduce this dependency, we need to adapt energy consumption to when green power is available or store it for later use, for example in batteries.

Batteries can be costly, but the Netherlands already has thousands of them on the road: electric vehicles (EVs). With smart charging solutions, these mobile batteries can play a vital role in keeping the grid balanced. Equans is putting this vision into practice.

Smarter charging for a balanced grid

Equans is one of the largest Charge Point Operators in the Netherlands, installing, managing, and operating thousands of charging stations. In partnership with ENGIE, which supplies green electricity, Equans is testing new ways to make charging more flexible.

Traditionally, once you plug in an EV, charging starts immediately and stops when the battery is full. However, on average, cars remain plugged in twice as long as needed to fully charge. This untapped time offers an opportunity: charging can be temporarily slowed or paused when the grid is under pressure.

Making this work, however, is complex. No project of this scale had been attempted before, requiring adjustments to operational processes and overcoming significant technical hurdles. Existing software wasn’t designed to manage charging flexibility on such a large scale. Most importantly, the solution needed to ensure EV drivers were not inconvenienced.

Maximum grid impact, minimal driver impact

To achieve this, Equans and ENGIE co-developed new tools. ENGIE created a virtual power plant that automatically reduces electricity consumption during grid shortages by temporarily slowing EV charging. These interventions are short — typically 5 to 10 minutes — and limited to a few times a day, ensuring drivers notice little to no difference.

Together with Smatch — ENGIE’s smart charging solution — Equans built a platform that reacts instantly when ENGIE signals a shortage. The platform continuously monitors the impact on drivers, adjusting rules whenever necessary to guarantee a seamless experience.

CO₂-Free, controllable power

In the Rotterdam region, Equans installed over 16,000 charging points while ENGIE supplies renewable energy. The scale of this infrastructure gives the virtual power plant significant influence on grid stability and demonstrates the project’s potential for further expansion.

Currently, the system provides approximately 16 MW of CO₂-free, controllable capacity — equivalent to the output of 40,000 solar panels. With future scaling, this approach could significantly reduce the need for fossil-fuelled power plants to stabilise the grid.

And it’s user-friendly: to date, there’s been no noticeable difference in how drivers use the charging stations. This is a strong sign that the system works without compromising the user experience.

The Road Ahead

Flexibility through EV charging will be essential to delivering a successful energy transition. The “Charging on Balance” project has already proved its effectiveness — but this is just the start. Equans aims to expand the project across all charging stations in the Rotterdam region and into other provinces and municipalities. The more stations connected to the virtual power plant, the greater the controllable capacity — and the lower the CO₂ emissions.

Next, the algorithm will be enhanced to respond even faster and more intelligently to fluctuations in the electricity market, while continuing to ensure EV drivers remain unaffected. Smart charging is just one piece of the wider energy transition puzzle. By unlocking flexibility from public charging stations, we can reduce our reliance on fossil-fuelled power plants. With every electric journey, we move closer to achieving our climate goals.