NOVELTY - The device has a turbine (30) with multi-stage turbo expand format and a generator (60) mounted to a shaft, where the turbine and generator are exposed within a monocoque chamber. A sealed shell is housing the turbine and the generator. A propellant mixture lubricates bearing systems of the device and cools the generator by exhausted gases exiting from the turbine within the sealed shell. A throttle control (40) regulates the flow of the mixture through the turbine. A centering and support bearings is located at a top and a base of the turbine and the generator respectively.    USE - Used for generating electrical power and installed in hostile e.g. temperature and chemical environments on the earth`s surface.    ADVANTAGE - The turbine and the generator are exposed within the monocoque chamber and encased in porous raceways, thus eliminating the need of the separate lubrication for bearing systems of the turbine and the generator. The design configuration of the generator reduces/eliminates the gas leakage and allows the transferring of the generated electrical energy to the outside of the housing with total safety and ready to attach with the cables. The provision of the propellant mixture permeates the monocoque sealed shell, thus lubricating the bearing systems. The design configuration of the device provides a low cost alternative power generating device for closed loop circuit generators through the ability of ease of mass production and adaptation to generating systems. The design configuration of the device provides a self-contained, self-cooling, self-lubricating power generating device.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for an energy producing apparatus comprising a heat exchange device.    DESCRIPTION OF DRAWING(S) - The drawing shows a view of a monocoque turbo- generator device.    Heat exchange feed line (20)    Heat exchange interface case (25)    Turbine (30)    Throttle control (40)    Transverse tube tunnel (50)    Generator (60)    Coupling shaft dome (70)    Drive shaft (80)    Exhaust tube plenums (90)