A compact energy cycle construction that utilizes a working fluid in its operation is disclosed having a compact housing of a generally cylindrical form, an orbiting scroll type expander, a central shaft which is driven by the expander, a generator having a rotor and a stator with the central shaft being mounted to the rotor for rotating the rotor relative to the stator, a pump mounted to the central shaft, an evaporator positioned between the expander and the generator and surrounding the central shaft, and the orbiting scroll type expander, the central shaft, the generator, the pump, and the evaporator being housed within the compact housing to form an integrated system operable in accordance with an energy cycle.

A compact energy cycle construction that operates as or in accordance with a Rankine, Organic Rankine, Heat Pump, or Combined Organic Rankine and Heat Pump Cycle, comprising a compact housing of a generally cylindrical form with some combination of a scroll type expander, pump, and compressor disposed therein to share a common shaft with a motor or generator and to form an integrated system, with the working fluid of the system circulating within the housing as a torus along the common shaft and toroidally within the housing as the system operates.

A compact energy cycle construction that operates as or in accordance with a Rankine, Organic Rankine, Heat Pump, or Combined Organic Rankine and Heat Pump Cycle, comprising a compact housing of a generally cylindrical form with some combination of a scroll type expander, pump, and compressor disposed therein to share a common shaft with a motor or generator and to form an integrated system, with the working fluid of the system circulating within the housing as a torus along the common shaft and toroidally within the housing as the system operates.