An electrical generator includes a rotor, a stator core disposed axially around the rotor, a stator sleeve assembly disposed axially around the stator core, and a stator housing disposed axially around the stator sleeve assembly. The stator sleeve assembly includes a cylindrical stator sleeve and thermoelectric elements. The cylindrical stator sleeve has a radially inward facing surface and a radially outward facing surface. The thermoelectric elements are affixed to the radially outward facing surface of the cylindrical stator sleeve. The stator housing includes at least one coolant channel. The coolant channel is in thermal contact with the thermoelectric elements. The thermoelectric elements generate power as a function of the temperature difference between the cylindrical stator sleeve and the coolant channel.