General Electric will evaluate a highly efficient heat engine for natural gas pipeline compression. The project is centered on the conceptual design of a novel, hermetically sealed oil-free super-critical carbon dioxide (SCO₂) bottoming cycle for a natural gas combustion turbine used for pipeline compression. The effort enables heat engine cycle efficiencies >50% by demonstrating the feasibility of a two-machine oil-free drivetrain consisting of a high-speed SCO₂ turbo-compressor with a direct drive starter-generator aerodynamically coupled to a 60hz 10MW SCO₂ turbo-generator. The primary deliverable of this project is the conceptual design of a 10MW SCO₂ bottoming cycle and associated turbomachinery. The conceptual design includes an integrated approach between different disciplines such as thermodynamic cycles, aero design, rotor dynamics, bearing design, and electric machine sizing. One project outcome will be the definition of a suitable SCO₂ bottoming cycle for highly-efficient heat engines that is deployable into remote locations with minimal to no operation oversight. Another outcome is the development of a process gas lubricated bearing system for MW-class turbomachinery for implementation in SCO₂.