A rotor for a pneumatic tool having electricity-generating capabilities comprises a shaft and an integral rotor body. The rotor body includes recesses dimensioned to receive an insulated subassembly comprising a magnet received within a nonmagnetic insulator. The nonmagnetic insulator acts to allow flux to be concentrated against stator windings. The improved rotor can be fitted with the insulated subassemblies in order to cooperate with a stator in the tool to generate electricity upon rotation of the rotor when pressurized fluid is applied to the vanes. A ring stator is supportable by a nonmagnetic end plate of the pneumatic tool, is disposed between the rotor and the rotor bearing and is preferably formed of Silicon Core Iron “B-FM” and magnet wire.