Filed under: Hybrid , Technology , Hatchback , Toyota If rumors are to be believed, big changes are in store for the next Toyota Prius . UK outlet Auto Express recently spoke with a Toyota engineer who leaked details concerning the development of the popular hybrid’s successor. According to that engineer, “The next Prius will redefine the hybrid as we know it.” The forthcoming Prius will be constructed on a new C platform, good for a 70-kilogram (153-pound) reduction in weight. The car’s current 1.8-liter engine will be modified, and the electric motor and power inverter will be downsized. But, according to the Auto Express source, it will deliver more power. It will also be more fuel efficient – which we kind of assumed – however, the source is claiming 90 miles per gallon fuel economy (on the UK cycle, we imagine, so something closer to 75 mpg here). If true, that’s definitely impressive. While the standard Prius will get these drivetrain changes, the plug-in version will remain largely the same. That said, both models will receive an electric motor that drives the rear wheels, as part of an e-4WD system. According to the source, Toyota would be, “targeting snowy areas” and said that the rear wheels will be driven at speeds “up to 37 mph.” Interestingly enough, Toyota will stick with nickel-metal hydride battery for the Prius, with lithium-ion fitted for the plug-in model.