Gyrodrive Original Equipment Development

A flywheel system originally built for Le Mans racing cars will now be fitted as standard equipment on new city buses. The technology, called Gyrodrive, captures energy normally lost when a bus brakes and stores it in a high-speed spinning flywheel. That stored energy then helps accelerate the bus again, cutting fuel use. Previous tests on retrofitted buses showed fuel savings of more than 25 percent. The problem is that retrofitting existing buses is expensive and limits how widely the technology can spread. This project brings together the flywheel developer Williams Hybrid Power, the manufacturer GKN, and Alexander Dennis Limited—the UK’s largest bus builder—to design the system so it can be installed during bus manufacture, not added later. That shift from retrofit to original equipment should lower costs, increase production volumes, and open export markets. If successful, the project could make city buses significantly cheaper to run while reducing their carbon emissions. GKN also plans to adapt the same flywheel technology for off-highway vehicles such as construction and mining machinery, where braking energy is also wasted. The direct impact on daily life would be quieter, more efficient buses on city streets, and lower operating costs for public transport operators.