Beyond transport: Electric buses are becoming power sources, emergency assets and energy market players

“The future of bus transport is not just electric. It’s intelligent,” says VTT’s Senior Scientist Yancho Todorov.

Every two years, the world’s largest bus exhibition, Busworld in Brussels, gathers manufacturers, consultancies and researchers to showcase the latest developments in public transport.

This year’s event, Todorov notes, left no doubt: the future is already electrified. The question is no longer whether electrification is possible, but how to make it work efficiently in practice.

“Electric bus technologies are already quite mature. The biggest challenges are now related to infrastructure and asset optimisation: how to optimise charging networks and adapt bus fleets to local conditions such as climate, terrain and urban density.”

In many cities, electric bus fleets are expanding rapidly. What used to be experimental has become an everyday reality, and the focus has shifted to optimising investment and operational costs (CAPEX and OPEX).

“We’re seeing a strong emphasis on digital tools, smart charging systems and simulation-based planning,” Todorov explains. “Virtual piloting allows operators to test different fleet configurations, routes and energy use scenarios before making costly investment decisions. This helps to reduce the risk of purchasing vehicles and creating transport systems that don’t fully meet operational needs.”

For instance, weather conditions, street layouts, elevation and the placement of depots or opportunity charging stations can significantly affect fleet performance. Simulations help operators understand these constraints and prepare for potential disruptions from power shortages to extreme weather events.

Battery technologies are improving rapidly, and the new generation of electric buses can operate longer with high-capacity batteries that will gradually eliminate the need for opportunity charging in some routes. This enables simpler infrastructure and more flexible scheduling.

“Thanks to higher battery capacity, we can now think beyond mobility,” Todorov says. “Electric buses can act as mobile energy storage units supporting the grid during peak hours or even serving as emergency power sources in disasters or large-scale evacuations.”

The concept, known as Vehicle-to-Grid (V2G), enables buses to discharge electricity back into the grid when demand is high and generate profit for their owner. Combined with smart charging that takes advantage of low-price periods, this can significantly reduce operational costs.

The EU’s new Battery Regulation is important not only for its environmental impact but also for its economic impact. The regulation will require unique identification numbers for each battery cell and detailed data on battery charging cycles by 2027, paving the way for a battery second-life market.

“Operators could sell or reuse batteries that are no longer optimal for buses but still useful for stationary storage. In practical terms this would mean lower CAPEX by transferring the remaining value of a second life battery to a new one leading to longer fleet operational lifecycle. In some cases, selling used batteries could reduce the cost of new ones by up to 25 per cent.”

Another promising avenue is the shared use of charging infrastructure in bus depots.

“Most depots are only fully used at night, and mostly empty during morning and afternoon rush hours,” Todorov explains. “Opening them up for other electric vehicles throughout the day, such as long-distance coaches or heavy-duty trucks, could create new revenue streams for operators and optimize the power usage at the depot.  Megawatt-level charging technologies present quite good prospects to make this possible and attractive as an option.”

The next three to five years, Todorov predicts, will be about integration and cost efficiency. “We will see a move towards connecting vehicles, depots, and energy markets into one intelligent ecosystem.”

From a long-term perspective “Automation will also enter the picture,” he says. “In smaller towns or lines with a social function and low frequency of usage, driverless buses could make public transport more affordable and cost efficient while maintaining social accessibility.”

For now, though, the focus remains clear: turning data and simulation into practical decisions.

“The technology exists,” Todorov says. “Now it’s about making the system work — reliably, economically, and sustainably — for every city’s unique needs.”