Electric bus batteries reused to store solar energy

Batteries from retired electric buses will be used to store solar energy via a new housing association research project in Gothenburg, Sweden.

The ‘energy warehouse’ is giving electric bus batteries a second lease of life as part of a collaboration between Volvo Buses, Göteborg Energi, Riksbyggen and Johanneberg Science Park. The partners will be working together to examine electricity storage in apartment blocks that have their own electricity production via solar panels.

The research is taking place in Riksbyggen’s Viva housing cooperative in Gothenburg, an apartment complex that aims to be Sweden’s most innovative and sustainable housing project. Energy generated via the solar panels on the roof will be stored in batteries that previously powered the Volvo electric buses on Route 55.

The energy warehouse is used to cut the property’s power consumption peaks, and to store or sell surplus solar energy back to the grid.

“We know that electric bus batteries have good potential for other applications such as energy storage after the end of their life in public transport,” says Ylva Olofsson, Project Coordinator at Volvo.“What we are examining here is exactly how good that potential is. Use of the batteries in an energy warehouse gives them an extended service life which in turn means better resource utilisation and less environmental impact.

“Here at Volvo we are examining various possibilities for the reuse of bus batteries for energy storage, and Viva is one such example.”

The battery warehouse consists of 14 used lithium-ion electric bus batteries. They are installed in a battery chamber and linked together to create a 200 kWh storage pack.