A system for electromagnetically transferring heat from one region to another region. To cool one region in a chamber, antennas in the chamber to be cooled preferably have a broad beam to collect thermal radiation as much as possible within the chamber. Antennas to be used for heat pumping are preferably of high directivity where the antenna beam is pointed to a cold region such as the zenith of the sky. The system for electromagnetic heating is similar to that for electromagnetic cooling except heat flow is reversed. Here, the antennas outside a chamber have a highly focused beam to a hot area, such as the sun. The collected heat is channeled into an area to be heated by low-directivity antennas within an enclosed volume to be heated.

A heat pump is provided with a compressor; an oil separator provided on a discharge path of the compressor; an accumulator connected to the compressor via a suction path; and a bypass circuit configured to supply a gas refrigerant separated by the oil separator. The bypass circuit is connected to the suction path.

Disclosed is a two-stage heating geothermal system using geothermal energy. The two-stage heating geothermal system includes a geothermal heat exchanger, a geothermal heat pump, a booster heat pump, a bypass line, and a bypass line opening and closing valve. The operating efficiency of the two-stage heating geothermal system using geothermal energy is significantly improved. Hot water supply, auxiliary heating, and the like are controlled to be completely independent of main heating.

Disclosed is a two-stage heating geothermal system using geothermal energy. The two-stage heating geothermal system includes a geothermal heat exchanger, a geothermal heat pump, a booster heat pump, a bypass line, and a bypass line opening and closing valve. The operating efficiency of the two-stage heating geothermal system using geothermal energy is significantly improved. Hot water supply, auxiliary heating, and the like are controlled to be completely independent of main heating.

An air conditioning system is provided and including a solar heat generator configured for collecting solar radiation and for heating fluid by the solar radiation and a fluid container coupled to the solar heat generator and being configured to maintain the heated fluid. The system further includes a heat exchanger disposed inside the fluid container and being configured for transferring heat from the heated fluid to refrigerant inside the heat exchanger, the heat exchanger is configured to increase pressure and temperature of the refrigerant. The system further includes a condenser, an expansion member and an evaporator configured to form together with the heat exchanger an air-conditioning cycle.

In this container refrigerator, the permissible equivalent negative-phase-sequence current of a generator to be connected is calculated in Step S3 based on its capacitance. Next, in Step S4, the power consumption of an inverter device to generate the equivalent negative-phase-sequence current is calculated. Then, in Step S6, the equivalent negative-phase-sequence current generated by the container refrigerator is calculated based on the power consumption of this inverter device. Thereafter, in Step S9, I.sub.t is compared to I.sub.tg. If I.sub.t>I.sub.tg is satisfied, I.sub.t is restricted until I.sub.t≦I.sub.tg is met by lowering the output frequency of the inverter device repeatedly in multiple stages. Consequently, even if the generator connected has small capacitance, the operation may be continued at a number of rotations appropriate for that small capacitance without causing the generator to overheat or be burned out.

In this container refrigerator, the permissible equivalent negative-phase-sequence current of a generator to be connected is calculated in Step S3 based on its capacitance. Next, in Step S4, the power consumption of an inverter device to generate the equivalent negative-phase-sequence current is calculated. Then, in Step S6, the equivalent negative-phase-sequence current generated by the container refrigerator is calculated based on the power consumption of this inverter device. Thereafter, in Step S9, I.sub.t is compared to I.sub.tg. If I.sub.t>I.sub.tg is satisfied, I.sub.t is restricted until I.sub.t≦I.sub.tg is met by lowering the output frequency of the inverter device repeatedly in multiple stages. Consequently, even if the generator connected has small capacitance, the operation may be continued at a number of rotations appropriate for that small capacitance without causing the generator to overheat or be burned out.

An example transport refrigeration system includes first and second refrigeration circuits configured to cool first and second transport compartments, respectively. An electric machine powers the first and second refrigeration circuits. A controller is configured to monitor a temperature of the electric machine, and reduce a cooling capacity of a selected one of the first and second refrigeration circuits based on the temperature exceeding a first threshold.

An example transport refrigeration system includes first and second refrigeration circuits configured to cool first and second transport compartments, respectively. An electric machine powers the first and second refrigeration circuits. A controller is configured to monitor a temperature of the electric machine, and reduce a cooling capacity of a selected one of the first and second refrigeration circuits based on the temperature exceeding a first threshold.

Techniques for providing carbon dioxide include generating thermal energy, an exhaust fluid, and electrical power from a power plant; providing the exhaust fluid and the generated electrical power to an exhaust fluid scrubbing system to separate components of the exhaust fluid; capturing heat from a source of heat of an industrial process in a heating fluid; transferring the heat of the industrial process captured in the heating fluid to a carbon dioxide source material of a direct air capture (DAC) system; providing the generated electrical power from the power plant to the DAC system; providing the thermal energy from the power plant to the DAC system; and separating, with the transferred portion of the heat of the industrial process and the provided thermal energy, carbon dioxide from the carbon dioxide source material of the DAC system.