Polish bus manufacturer Solaris said its electric bus retrofit programme now covers around 170 vehicles across Europe, as operators seek to extend the lifespan of early-generation battery-electric fleets.
The update was shared during the Mobility Move event in Berlin, with details reported by Sustainable Bus. The programme includes 105 buses for Berliner Verkehrsbetriebe (BVG), as well as additional vehicles in cities such as Kraków, Cluj-Napoca, Hamburg, Jaworzno, Brussels and Warsaw.
Solaris said the retrofit initiative targets approximately 1,325 battery-electric buses delivered between 2013 and 2019, representing about 22% of its electric fleet currently in operation. The company aims to prevent older vehicles from being retired prematurely by replacing key components, particularly batteries, under its “Zero-Emission Vehicle Retrofit” programme.
When the service was launched in December, Solaris said it was designed to provide operators with an “effective solution” to maintain the competitiveness of early electric buses in public transport fleets. The programme allows for “post-warranty replacement of EV components with new ones,” the company said.
The retrofit includes battery replacement, upgrades to thermal management systems, and updates to battery management systems, along with compatibility checks for existing charging infrastructure. Operators can choose between different battery chemistries, including LFP, NMC and LTO, depending on operational needs.
Solaris highlighted that rapid technological advancements in battery systems have accelerated obsolescence in earlier electric bus models. The company described this as a technological evolution “taking place in a relatively short time with an unprecedented evolution of the solution defined,” adding that such changes can lead “to technological obsolescence during the normal vehicle exploitation period.”
The programme reflects a broader trend in the industry, where manufacturers are increasingly offering upgrade solutions for early electric vehicles. Daimler Buses, for example, has introduced battery services for its eCitaro model and plans to offer upgrades to newer battery generations from 2026.
Solaris said it provides comprehensive support during retrofits, including technical analysis, documentation, battery replacement and integration of updated components. Pricing details for the service were not disclosed.