Abstract: An air-handling system selectively heats and/or cools a target space by circulating ambient air from the target space across a heat exchanger. The system operates along an air flow path having an inlet from the target space and an outlet back into the target space. Air-handling turbines or pumps are located near the inlet and outlet. The heat exchanger is placed in the flow path between the turbines or pumps. The heat exchanger transfers heat into or out of the air, causing a natural pressure increase or decrease in the air. The turbines or pumps are configured to harvest work from the induced pressure differential in order to conserve energy. A combustion chamber may be included directly in the flow path upstream of the heat exchanger for combusting a fuel in the air during a high heating mode.

Abstract: Devices and methods for moving a working fluid through a controlled thermodynamic cycle in a positive displacement fluid-handling device (20, 20?, 20?) with minimal energy input include continuously varying the relative compression and expansion ratios of the working fluid in respective compressor and expander sections without diminishing volumetric efficiency. In one embodiment, a rotating valve plate arrangement (40, 42, 44, 46) is provided with moveable apertures or windows (48, 50, 56, 58) for conducting the passage of the working fluid in a manner which enables on-the-fly management of the thermodynamic efficiency of the device (20) under varying conditions in order to maximize the amount of mechanical work needed to move the target quantity of heat absorbed and released by the working fluid. When operated in refrigeration modes, the work required to move the heat is minimized. In power modes, the work extracted for the given input heat is maximized.

Abstract: Devices and methods for moving a working fluid through a controlled thermodynamic cycle in a positive displacement fluid-handling device (20, 20?, 20?) with minimal energy input include continuously varying the relative compression and expansion ratios of the working fluid in respective compressor and expander sections without diminishing volumetric efficiency. In one embodiment, a rotating valve plate arrangement (40, 42, 44, 46) is provided with moveable apertures or windows (48, 50, 56, 58) for conducting the passage of the working fluid in a manner which enables on-the-fly management of the thermodynamic efficiency of the device (20) under varying conditions in order to maximize the amount of mechanical work needed to move the target quantity of heat absorbed and released by the working fluid. When operated in refrigeration modes, the work required to move the heat is minimized. In power modes, the work extracted for the given input heat is maximized.