Systems and methods utilize a cogeneration system for providing heating, cooling, and/or electricity to an enclosure. The system includes a heat engine for heating and supplying electricity to the enclosure through fluid transfer from the heat engine to the enclosure to transfer thermal energy from the fluid to the enclosure. The system further includes a heat pump configured to supply at least heating and cooling to the enclosure through movement of fluid from the heat pump to the enclosure to transfer thermal energy from the fluid to the enclosure.

Systems and methods utilize a cogeneration system for providing heating, cooling, and/or electricity to an enclosure. The system includes a heat engine for heating and supplying electricity to the enclosure. Coupled to the heat engine is a first conduit configured to transfer fluid from the heat engine to the enclosure to transfer thermal energy from the fluid to the enclosure. The system further includes a heat pump configured to supply at least heating and cooling to the enclosure. Coupled to the heat pump is at least a second conduit. The second conduit is configured to move fluid from the heat pump to the enclosure to transfer thermal energy from the fluid to the enclosure.

Provided is a vehicle air-conditioning apparatus heat pump system configured so that an excessive increase in the temperature (superheat degree) of refrigerant discharged from a compressor can be prevented in air-heating operation. The heat pump system (HP) includes a compressor (C) and an indoor heat exchanger (HXC2) on a refrigerant circuit (RC). A first branched flow path (BC1) on which a first expansion mechanism (EX1) of which opening degree is adjustable and a first heat absorption heat exchanger (HXA1) are arranged in series and a second branched flow path (BC2) on which a second expansion mechanism (EX2) of which opening degree is adjustable and a second heat absorption heat exchanger (HXA2) are arranged in series are arranged in parallel on the refrigerant circuit extending from the indoor heat exchanger to the compressor.

A recovery system is provided to recover energy from heat. In an embodiment, the system includes an evaporator to receive a flow of natural gas at a first temperature and output the flow at a second, lower temperature. The evaporator may receive a flow of cooling media to cool the natural gas and output a flow of heated cooling media. The system may further include: a heat-to-mechanical energy converter coupled to the evaporator to receive the flow of heated cooling media and to output first cooled cooling media; an induction generator coupled to be driven by the heat-to-mechanical energy converter; a medium voltage drive coupled to receive power from the induction generator and to condition the power for output to an electrical distribution system; and a condenser to condense the first cooled cooling media to provide the flow of cooling media to the evaporator.

A recovery system is provided to recover energy from heat. In an embodiment, the system includes an evaporator to receive a flow of natural gas at a first temperature and output the flow at a second, lower temperature. The evaporator may receive a flow of cooling media to cool the natural gas and output a flow of heated cooling media. The system may further include: a heat-to-mechanical energy converter coupled to the evaporator to receive the flow of heated cooling media and to output first cooled cooling media; an induction generator coupled to be driven by the heat-to-mechanical energy converter; a medium voltage drive coupled to receive power from the induction generator and to condition the power for output to an electrical distribution system; and a condenser to condense the first cooled cooling media to provide the flow of cooling media to the evaporator.

Proposed is a gas heat-pump system including: a compressor discharging compressed refrigerant; an indoor heat exchanger causing heat exchange to occur between indoor air and the refrigerant; an outdoor heat exchanger condensing the refrigerant; a four-way valve switching a flow direction; an engine; a radiator cooling heated coolant; an exhaust gas heat exchanger causing the heat exchange to occur between the coolant passing through the radiator and exhaust gas from the engine; and a first three-way valve switching a flow direction of the coolant and controlling an amount of the flowing coolant in such a manner that the coolant passing through the radiator flows toward at least one of the exhaust gas heat exchanger and the engine.

Proposed is a gas heat-pump system including: a compressor discharging compressed refrigerant; an indoor heat exchanger causing heat exchange to occur between indoor air and the refrigerant; an outdoor heat exchanger condensing the refrigerant; a four-way valve switching a flow direction; an engine; a radiator cooling heated coolant; an exhaust gas heat exchanger causing the heat exchange to occur between the coolant passing through the radiator and exhaust gas from the engine; and a first three-way valve switching a flow direction of the coolant and controlling an amount of the flowing coolant in such a manner that the coolant passing through the radiator flows toward at least one of the exhaust gas heat exchanger and the engine.

Proposed a gas heat-pump system including: a compressor compressing refrigerant and discharging the compressed refrigerant; an engine providing a drive force to the compressor; a radiator that cools coolant which is heated while passing through the engine; an indoor heat exchanger causing heat exchange to occur between indoor air and the refrigerant and thus cooling or heating an indoor space; an outdoor heat exchanger condensing the refrigerant; a four-way valve switching a flow direction of the refrigerant in such a manner that the refrigerant discharged from the compressor flows to the outdoor heat exchanger in a cooling operation mode and flows to the indoor heat exchanger in a heating operation mode; and a hot-water storage tank causing the heat exchange to occur between stored water and the refrigerant, and thus cooling the refrigerant in the cooling operation mode and heating the refrigerant in the heating operation mode.

Proposed is a gas heat-pump system capable of supplying recirculation exhaust gas to an engine using an exhaust gas turbocharger and thus actively controlling an amount of the flowing recirculation exhaust gas and pressure thereof.

The integrated desalination and air conditioning system can provide desalinated (fresh) water, cold air or both in a single efficient system. The system incorporates a humidification-dehumidification (HdH) desalination system with a water-lithium bromide (H.sub.2O—LiBr) vapor absorption cycle (AbC) system. The AbC system includes an AbC generator that provides a heating source for an AbC condenser that heats the air input of the HdH; two AbC absorbers that provide heating sources for the feed seawater; a first AbC evaporator that provides a cooling source for the humidified air produced in the HdH; and a second AbC evaporator that provides a cooling source for use outside the system. The heat input for the AbC generator can be provided by low-grade heat sources, such as waste heat or solar thermal energy. The system is capable of producing fresh water and/or cold air at different capacities, depending on water demands and cooling load requirements.