BMW Files Patent That Could Allow EVs to Harness Energy From Speed Bumps

A patent from BMW would create a new vehicle suspension design that could harness energy as the vehicle drives over speed bumps.

CarBuzz, a website for vehicle news, uncovered documents from the German Patent and Trade Mark Office for a suspension design by BMW that could obtain energy from speed bumps and other road obstacles. By doing so, it could charge EVs as they drive.

As a vehicle drives it usually absorbs energy from road obstacles into the springs of the suspension, and the energy then dissipates as heat. But BMW’s design includes a generator that, through an actuator, connects to a suspension control arm. As a wheel goes over a bump, a stabilizer arm twists and rotates the actuating disc, CarBuzz explained. The wheel goes back down to meet the road after passing the obstacle, and the energy moves to the spring. 

The stabilizer arm and actuating disc rotate again, and the one-way clutch engages and uses a gear mechanism to increase the speed, torque and rotation of the flywheel on the generator. Then, the energy can be stored in a 12V electrical battery or high-voltage traction batteries.

CarBuzz predicts that the patented idea, if sent to production, could be found in electrical versions of BMW’s flagship vehicles. Inside EVs notes that this feature may be considered premium and will come at a higher cost rather than being included on basic EV models or could be offered on a subscription basis.

But as The Verge, which also obtained and verified the patent documents, pointed out, many vehicle manufacturers file patents often, but that doesn’t mean they will all come to fruition. BMW is also not the only company working on innovations similar to this that can harvest and use energy from vehicles as they encounter road obstacles. In October 2022, CarBuzz also reported that Gig Performance has showcased the Roadkil 5000, a suspension accessory that could harness energy from speed bumps and other bumps in the road and use it to extend an EV’s range.

A 2015 study also explored how to absorb and reuse energy from vibrations, particularly through energy recovery in the suspension via a dual-mass piezoelectric bar harvester. Another study from 2009 reviewed energy regeneration of active suspension for hybrid vehicles that could improve fuel economy and extend the life of the car battery.