Hyundai is the latest automaker to explore uses for so-called “second-life” electric-car batteries. It’s teaming up with Finnish energy-technology company Wärtsilä to use these batteries for stationary energy storage.
Even after they have degraded too much for continued automotive use, electric-car batteries still have plenty of usable storage capacity. Energy storage is an attractive second use for these batteries because it can boost the adoption of renewable energy. The more renewable-energy sources used to generate electricity, the greener electric cars become. It’s all connected.
While renewable-energy sources like wind and solar help reduce carbon emissions, the wind isn’t always blowing and the sun isn’t always shining. Energy storage helps adjust for the intermittent nature of these power sources by charging up with energy when it’s available, and discharging at a later time. Much of that energy would go to waste without storage batteries, since wind turbines and solar panels often harvest more than is needed at any given time.
Hyundai has already constructed a one-megawatt-hour test array using Ioniq Electric and Kia Soul EV batteries. Going forward, it plans to provide batteries to Wärtsilä, which will then market them to electric utilities and other companies as part of complete energy-storage systems.
Hyundai expects 29 gigawatt-hours of used electric-car batteries to be available by 2025, compared to the 10 GWh of batteries currently available for the energy-storage market. The prediction is based on an assumption of vastly expanded electric-car sales. Tesla has already pioneered the model of selling both electric cars and batteries for energy storage. BMW, Daimler, and Nissan have also discussed selling energy-storage battery packs, but not on the same scale as Tesla.
Other automakers have also experimented with alternative uses for electric-car batteries. Nissan plans to use Leaf batteries to power streetlights in a Japanese town devastated by the earthquake and tsunami that struck the country in 2011. Nissan partner Renault is using second-life batteries as part of its “Smart Island” project off the coast of Portugal. General Motors and Toyota have used batteries from the Chevrolet Volt and Camry Hybrid, respectively, in small-scale projects.