admin December 13, 2018

Electric bus batteries used to store solar energy

The inauguration of what is probably Europe’s first ever energy warehouse using electric bus batteries is currently under way. Batteries from electric bus route 55 in Gothenburg, Sweden, are getting a second lease of life for solar energy storage. It is part of a research project where Volvo Buses, Göteborg Energi, Riksbyggen and Johanneberg Science Park are working together to examine electricity storage in apartment blocks that have their own electricity production via solar panels.

The reuse and recycling of batteries is a key issue as increasing numbers of cities plan transition to electrically powered transport. Volvo Buses is taking part in a research project whereby used electric bus batteries get a second lease of life as solar energy storage units. 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 – Positive Footprint Housing. Tenants are just starting to move into their new apartments.

In Viva housing cooperative, Riksbyggen, Volvo, Göteborg Energi and Johanneberg Science Park have created a unique system whereby energy from solar panels on the roofs of the apartment buildings is stored in batteries that previously powered 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. It can also be used to buy and store electricity from the national grid when it is cheap and green, for later use. This improves the efficiency of housing association Viva’s own energy system as well as that of the city’s power 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. 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,” says Ylva Olofsson, Project Coordinator at Volvo.

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. This energy warehouse allows a larger proportion of Viva’s solar-generated electricity to be used for the housing association’s power needs.
About Riksbyggen Brf Viva
Brf Viva consists of a total of 132 apartments. The aim of Brf Viva is to create Sweden’s most innovative and sustainable housing project based on Positive Footprint Housing, (PFH) research. Solar systems, energy storage, heat recovery from ventilation (FTX), car and electric cycle pools, youth seats, distance workplaces and resource-efficient construction in climate-smart concrete show the way to the sustainable living of the future.
PFH is multidisciplinary research for overall thinking about innovative sustainable residential and urban development. The project will result in increased environmental, social and economic sustainability, with acquired insights and lessons gaining its first practical application in Brf Viva. The project was initiated by Riksbyggen in collaboration with, among others, Johanneberg Science Park, Chalmers, Gothenburg University, Gothenburg Energy, City of Gothenburg and RISE.
Some parts, such as energy storage in used bus batteries, are supported by the EU project IRIS Smart Cities. IRIS is a five-year Light House project funded by the EU’s HORIZON 2020. Within IRIS, seven cities, of which Gothenburg are one of them, will develop and test smart, sustainable solutions in energy, mobility and ICT, as well as disseminate solutions across Europe.

Facts

  • The energy storage consists of 14 used lithium ion batteries from route 55
  • The energy stored in the batteries comes from solar cells on the roofs of the property. The batteries can also be charged with renewable electricity from the surrounding power grid when the price is low
  • Energy storage is used to cut off the power ups of the properties. The self-produced soles can be used, stored or sold, whichever is most advantageous at the moment.
  • The energy storage (200 kWh) means that only four percent of the own-produced soles need to be sold compared with 20 percent without energy storage
  • A full energy storage is enough to charge approximately 4.5 electric cars (40 kWh), 30 electric bikes (0.5 kWh) and drive five washing machines (per 1 kWh)