Berlin-based roaming specialist Hubject has teamed up with Heliox, Accelera by Cummins and Blue Bird to enable the first commercial launch of an interoperable, standards-compliant vehicle-to-grid (V2G) charging solution based on ISO 15118-20. The focus is on electric school buses in the USA that not only draw power from the grid but also feed it back to support grids and enable new revenue streams.