A gaseous compression system for compressing a gas from an initial pressure to an exit pressure with a first, blower compression bank and a second, mechanical compression bank. Each compression bank has plural stages of gaseous compression with a gaseous fluid compressor and a heat pump intercooler. The heat pump intercooler comprises a cascading heat pump intercooler with a high temperature section, a medium temperature section, and a low temperature section, each temperature section with an intercooler core. Each stage of the blower compression bank has a high-pressure blower, and each stage of the mechanical compressor bank has a mechanical compressor. A final stage of gaseous compression is without a heat pump intercooler. Gas compressed by the gaseous fluid compression system can be injected into a gas-driven generator to generate electric power from movement of a working fluid induced by injection of the compressed gas.

The disclosed technology includes devices, systems, and methods for heat pump systems configured to operate in low ambient temperatures. The disclosed technology can include a heat pump water heater system having an evaporator, a first compressor configured to compress refrigerant to a first pressure, and a second compressor configured to compress the refrigerant to a second pressure. The second pressure can be greater than the first pressure. The heat pump water heater system can include a preheater configured to receive the refrigerant at the first pressure and heat water and a condenser configured to receive the refrigerant at the second pressure and heat water. The water can be passed through the preheater before being passed through the condenser.

There is disclosed a multi-stage air handling unit for linear capacity output comprising condenser coils, expansion valves, evaporator coils, and compressors. The condenser coils convert a refrigerant from a gas state to a liquid state to transfer heat to a first air medium. The expansion valves decrease pressure in the refrigerant. The evaporator coils convert the refrigerant from the liquid state to the gas state to transfer heat from a second air medium. The compressors increase pressure in the refrigerant and provide the linear capacity output. The compressors consist of one variable capacity compressor and at least one constant capacity compressor. For other aspects, data associated a multi-stage air handling unit is collected, a scroll compressor may be identified, the air handling unit is converted, a multi-stage compressor may be determined, and multiple states of the compressors are operated as linear capacity output.

A cooling system includes a heat exchanger through which a refrigerant flows, the heat exchanger having a fluid passing therethrough such that heat is rejected to the fluid, an evaporator, a refrigerant piping split point that receives the refrigerant at a given pressure from the heat exchanger and splits the refrigerant flow into a first circuit and a second circuit, the first circuit having an expansion valve that receives the refrigerant at the given pressure, and the second circuit having a first turbine coupled to a first compressor, wherein the first turbine receives the refrigerant at the given pressure, and a set of valves arranged to direct the refrigerant through the first circuit, the second circuit, or both the first and second circuits based on ambient conditions of the cooling system.

A heat source device includes a heat medium channel through which a heat medium flows, a plurality of refrigerant circuits through which refrigerant circulates, and a plurality of heat-medium heat exchangers configured to cause heat exchange to be performed between the heat medium in the heat medium channel and the refrigerant in the refrigerant circuits. The plurality of heat-medium heat exchangers include a first heat-medium heat exchanger to which at least one of the refrigerant circuits is connected and a second heat-medium heat exchanger to which a greater number of the refrigerant circuits are connected than to the first heat-medium heat exchanger.

An air-driven generator system for generating electric power from movement of a working liquid. The system includes an air-driven generator that includes a liquid turbine system fluidically interposed between the lower end of an elongate gravitational distribution conduit and the lower ends of plural elongate buoyancy conduits. A heavy working liquid flows from the upper ends of the buoyancy conduits and is fed into the upper end of the elongate gravitational distribution conduit. Working liquid flows down the elongate gravitational distribution conduit to actuate the liquid turbine system. An injection of air into the working liquid in the plural elongate buoyancy conduits induces upward flow of the working liquid. The system includes a solar thermal heating system fluidically coupled to heat exchangers that transfer heat collected by the solar thermal heating system to the working fluid through a thermal transfer fluid circuit.

A refrigerator includes a controller that is configured to perform operations including driving a refrigerator compartment compressor, determining whether a sensed temperature in the refrigerator compartment satisfies a first temperature, driving, based on the sensed temperature in the refrigerator compartment satisfying the first temperature, a freezer compartment compressor, stopping the refrigerator compartment compressor, maintaining, after stopping the refrigerator compartment compressor, operation of the freezer compartment compressor, restarting the refrigerator compartment compressor, and varying a driving frequency of the refrigerator compartment compressor.

A method of controlling a refrigeration system including a medium temperature refrigeration load and a low temperature refrigeration load. The method includes selectively bypassing refrigerant between a medium temperature suction group and a low temperature suction group via a bypass line using an electronic valve positioned in the bypass line. The method also includes controlling flow of refrigerant between the medium temperature suction group and the low temperature suction group via a controller communicatively coupled to the valve, and modulating the valve at any position between a closed position and a full open position to vary an amount of refrigerant flow between the medium temperature suction group and the low temperature suction group in response to determining, via the controller, one or both of a state of the medium temperature suction group and a state of the low temperature suction group.

The present invention provides a system and method for an improved multistage, cascade refrigeration system using hot gas defrost to rid the evaporator of ice build-up which accumulates over time, while the air in the evaporator enclosure remains below the freezing point of water. The present invention thus provides greater defrost flexibility with increased ease of design and implementation than current refrigeration systems, which allows for more robust hot gas defrost function for multistage refrigeration systems, such that it is unaffected by temperature changes of the condensing fluid (ambient air temperature for air cooled condensers, water temperature for water cooled condensers), and can be readily adapted to any refrigerant suitable for a selected temperature range.

A refrigeration apparatus, comprising: a compressor, the compressor being provided with an air exhaust opening and an air return opening; a condenser, a first end of the condenser being connected to the air exhaust opening; an evaporator, a first end of the evaporator being connected to the air return opening, a throttling element being connected in series between a second end of the evaporator and a second end of the condenser; a first control valve, the first control valve being connected in series between the evaporator and the compressor; an air suction device, a gas port of the air suction device being connected between the first control valve and the air return opening; and a control device, the control device being connected to the compressor, the first control valve, and the air suction device.