Innovators at NASA’s Glenn Research Center have developed an automated pulse-and-glide technique using a flywheel energy storage system for on-road vehicles; the technology, which NASA Glenn says can improve fuel economy over existing internal combustion or battery hybrid systems by 40-100%, is available for licensing. Drivers can use a manual “pulse-and-glide” (PnG) driving technique—accelerating and decelerating an automobile in cycles of approximately 10-30 seconds—as a way to improve fuel economy. A 2009 SAE paper by a team from Virginia Tech and Argonne National Laboratory found that a simulated PnG driving strategy in a Ford Focus delivered 33-77% fuel economy improvement depending on different speed ranges and acceleration times. The fuel economy results of a 2004 Toyota Prius from simulation and testing showed 24-90% fuel economy improvement with PnG drive cycles compared to steady speed results.