Process for the manufacture of a concentrated solution, like a concentrated aqueous hydrogen peroxide solution, by distillation and evaporation of a dilute solution, in which the distillation and the evaporation are carried out in two distinct pieces of equipment which are easy to dismantle and to transport. The vehicle powertrain system also has at least one controller programmed to filter a frequency content of a speed or torque command for the electric machine corresponding to a resonant frequency of the engine, damper and electric machine to reduce resonance of the engine, damper and electric machine. When a user desires to power a device, the cable may be used to connect the device to the electronic equipment.