MAN's SPIRIT-E project shows eTrucks can feed up to 350 kW back into the grid

After three years of running, the SPIRIT-E research project involving MAN Truck & Bus has ended with a clear result: battery-electric trucks can not only draw electricity but also store it and feed it back, improving the economics of their operation. Eight project partners led by the Technical University of Munich (TUM) researched bidirectional charging for electric trucks and tested it in a real-world lab at the haulage company Spedition Schmid in Regensburg. The trucks were also shown to take part in electricity trading and to help the grid operator stabilise the network. The project examined under which conditions the technology can be made commercially viable for hauliers, grid operators and solution providers, and which hurdles remain before market maturity. The results were presented to the public on 30 October 2026.

Bidirectional charging functions were developed and tested both on the MAN eTGX and on mobile and stationary charging systems from project partner SBRS. The partners aligned the interfaces between vehicle, charging post, the charging operator's control software, the site's energy management, the electricity marketer and the grid operator. The work also produced a reservation system for charging stations and software that optimally plans depot charging of the eTrucks. The core of the project was the implementation of ISO 15118-20, the international standard for communication between vehicle and charging infrastructure when charging and discharging. In the real-world lab, a MAN eTGX with 480 kWh of usable energy fed power back through a bidirectional DC charging station at up to 350 kW into the local energy network of Spedition Schmid in Regensburg (vehicle-to-site) and into the public power grid (vehicle-to-grid); charging other vehicles from the truck battery (vehicle-to-vehicle) was also tested successfully.

Beyond the hardware, the project tested how a truck battery can be used on the electricity market: in a test environment run by software provider PowerBot, it played through how the eTruck buys power when it is cheap and sells it when it is expensive. Via the European platform EQUIGY, the partners also tested how electric trucks can help grid operators balance bottlenecks in the power grid. SPIRIT-E thus shows that the technical foundations for integrating electric trucks as flexible storage into the energy system exist, and that depot charging in particular is easy to plan, creating large potential to relieve the grid as fleets grow.

Whether bidirectional charging pays off depends on the user's individual circumstances: duty profile and mileage, standing times and battery size, electricity prices and grid fees, own generation such as photovoltaics, available connection capacity, and whether the stored power can be marketed to the electricity market or to the grid. It is particularly attractive for electric trucks with regular depot standing times and less than 100,000 km of annual mileage. Vehicle-to-site and vehicle-to-vehicle applications in particular unlock savings: internal project calculations found an average saving of around ten percent, with up to 20 percent lower energy costs possible under optimal conditions.