A rotor for a pneumatic tool having electricity-generating capabilities includes a shaft and an integral rotor body. The rotor body includes recesses dimensioned to receive an insulated subassembly having a magnet received within a nonmagnetic insulator to allow flux to be concentrated against stator windings. The rotor can be used in a conventional pneumatic tool, but can also 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 connected to a supporting circuit by a connector and is supportable by a nonmagnetic end plate of the pneumatic tool and is disposed between the rotor and the rotor bearing.