A quickly attachable electric generator device for producing electric power from surfaces of hot or cold pipes. The invention provides a thermoelectric unit which includes a pedestal comprised of a material with high thermal conductivity on which a thermoelectric module is located. The pedestal includes a heat transfer element made to conform to a hot or cold cylindrical surface. The module also includes a module-to-air heat transfer element and the thermoelectric module is compressed between the air-to-module element and the pedestal. This element is referred to as a heat sink when energy is extracted from a hot surface and is referred to as a heat source when energy is flowing from the air and a cold surface. In preferred embodiments the heat transfer element is a thin flexible heat conductor that conforms to the hot or cold surface of various shapes and serves as a heat transfer conduit to transfer heat to or from a rigid portion of the pedestal. Electric energy is generated from the heat flowing through the module.