 The company said it "cannot [reveal] the core part of this invention" yet, but it disclosed that the system used an onboard energy generator, which it called a "membrane electrode assembly", to extract the hydrogen using a "mechanism which is similar to the method in which hydrogen is produced by a reaction of metal hydride and water".The hydrogen was then used to generate energy to run the car.This led to speculation that the metal hydride is consumed in the process and is the ultimate source of the car's energy, making it a hydride-fuelled "hydrogen on demand" vehicle rather than water-fuelled as claimed.