METHODS AND SYSTEMS FOR DESICCANT AIR CONDITIONING USING PHOTOVOLTAIC-THERMAL (PVT) MODULES

1 . A desiccant air conditioning system for treating an air stream entering a building space, comprising:

a conditioner utilizing a liquid desiccant for dehumidifying the air stream in a warm weather operation mode and for humidifying the air stream in a cold weather operation mode;

a regenerator connected to the conditioner for receiving the liquid desiccant from the conditioner, said regenerator causing the liquid desiccant to desorb water in the warm weather operation mode and to absorb water in the cold weather operation mode;

an apparatus for moving the air stream through the conditioner;

an apparatus for circulating the liquid desiccant through the conditioner and regenerator; and

a photovoltaic-thermal (PVT) module for heating liquid desiccant to be introduced in the regenerator in the warm weather operation mode and for heating liquid desiccant to be introduced in the conditioner in the cold weather operation mode, the PVT module also including one or more photovoltaic cells for generating electrical power used in operating the desiccant air conditioning system.

2 . The desiccant air conditioning system of claim 1 , wherein the air stream entering the building space flows in a substantially horizontal direction through the conditioner and a return air stream from the building space or outdoor air flows in a substantially horizontal direction through the regenerator.

3 . The desiccant air conditioning system of claim 1 , wherein the air stream entering the building space flows in a substantially vertical direction through the conditioner and a return air stream from the building space or outdoor air flows in a substantially vertical direction through the regenerator.

4 . The desiccant air conditioning system of claim 1 , wherein the conditioner and the regenerator each include a filter media for holding and exposing liquid desiccant to an air stream, and wherein the conditioner and the regenerator each include one or more spray-heads for spraying the desiccant on the filter media.

5 . The desiccant air conditioning system of claim 1 , further comprising a heat pump or a cold source, and wherein in the warm weather operation mode, liquid desiccant from the conditioner is heated by the PVT module or the heat pump and transferred to the regenerator, and liquid desiccant from the regenerator is cooled by the cold source or the heat pump and transferred to the conditioner.

6 . The desiccant air conditioning system of claim 1 , further comprising a heat pump or a cold source, and wherein in the warm weather operation mode, liquid desiccant from the conditioner is cooled by the cold source or the heat pump and transferred to a spray-head in the conditioner, and wherein liquid desiccant from the regenerator is heated by the PVT module or the heat pump and transferred to the regenerator.

7 . The desiccant air conditioning system of claim 1 , further comprising a heat pump or a cold source, and wherein in the cold weather operation mode, liquid desiccant from the conditioner is cooled by the cold source or the heat pump and transferred to a spray-head in the regenerator, and wherein liquid desiccant from the regenerator is heated by the PVT module or the heat pump and transferred to a spray-head in the conditioner.

8 . The desiccant air conditioning system of claim 1 , further comprising a heat pump or a cold source, and wherein in the cold weather operation mode, liquid desiccant from the conditioner is heated by the PVT module or the heat pump and transferred to a spray-head in the regenerator, and liquid desiccant from the regenerator is cooled by the cold source or the heat pump and transferred to a spray-head in the conditioner.

9 . The desiccant air conditioning system of claim 1 , further comprising a humidifier for adding water vapor and another PVT module for adding heat to the air stream treated by the conditioner in the cold weather operation mode.

10 . The desiccant air conditioning system of claim 1 , further comprising a heat exchanger, wherein liquid desiccant is exchanged between the regenerator and the conditioner through the heat exchanger.

11 . The desiccant air conditioning system of claim 1 , further comprising:

an outer enclosure for protecting air conditioning system components from the environment; and

a solar inverter coupled to the one or more photovoltaic cells for inverting direct current electricity generated by the one or more photovoltaic cells to alternating current electricity, said solar inverter being positioned within the outer enclosure of the air conditioning system.

12 . The desiccant air conditioning system of claim 1 , wherein said PVT module comprises a water storage tank beneath the one or more photovoltaic cells for storing a heat transfer fluid heated by the PVT module and functioning as a ballast for the PVT module.

13 . The desiccant air conditioning system of claim 1 , wherein the PVT module comprises a thermal unit for heating a heat transfer fluid and a storage tank to store heat transfer fluid, and wherein the thermal unit and the storage tank are detachably mounted on the storage tank, and wherein the storage tank is configured to store the one or more photovoltaic cells and the thermal unit when the PVT module is in a disassembled state.

14 . The desiccant air conditioning system of claim 13 , further comprising removable supports for mounting the one or more photovoltaic cells and the thermal unit on the storage tank.

15 . The desiccant air conditioning system of claim 1 , further comprising a PVT module for preheating air entering the building space and generating electrical power used in operating the desiccant air conditioning system.

16 . The desiccant air conditioning system of claim 1 , further comprising a humidifier for humidifying the air stream treated by the conditioner in the cold weather operation mode and a PVT module for preheating water provided to the humidifier and generating electrical power used in operating the desiccant air conditioning system.

17 . The desiccant air conditioning system of claim 1 , further comprising a tank connected to the conditioner for storing the liquid desiccant used in the conditioner, wherein the liquid desiccant varies in concentration along the height of the tank, and further comprising a mechanism for drawing liquid desiccant from the tank at different selected heights of the tank in order to obtain liquid desiccant having a given concentration.

18 . A method for treating an air stream entering a building space, comprising:

conditioning the air stream by dehumidifying the air stream in a warm weather operation mode and humidifying the air stream in a cold weather operation mode utilizing a liquid desiccant;

regenerating the liquid desiccant used in conditioning the air stream by causing the liquid desiccant to desorb water in the warm weather operation mode and causing the liquid desiccant to absorb water in the cold weather operation mode; and

heating the liquid desiccant to be regenerated in the warm weather operation mode and heating the liquid desiccant to be used for conditioning the air stream in the cold weather operation mode utilizing a photovoltaic-thermal (PVT) module; and

generating electrical power used in operating the desiccant air conditioning system utilizing the PVT module.

19 . The method of claim 18 , further comprising forcing the air stream while being conditioned to flow in a substantially horizontal direction, and utilizing a return air stream from the building space flowing in a substantially horizontal direction for regenerating the liquid desiccant.

20 . The method of claim 18 , further comprising forcing the air stream while being conditioned to flow in a substantially vertical direction, and utilizing a return air stream from the building space flowing in a substantially vertical direction for regenerating the liquid desiccant.

21 . The method of claim 18 , further comprising cooling the liquid desiccant to be used in conditioning the air stream in the warm weather operation mode, and further comprising cooling the liquid desiccant to be regenerated in the cold weather operation mode.

22 . The method of claim 18 , further comprising transferring heat between the liquid desiccant to be used for conditioning the air stream and the liquid desiccant to be regenerated.

23 . The method of claim 18 , further comprising preheating air entering the building space using a PVT module.

24 . The method of claim 18 , further comprising humidifying the air stream treated by the conditioner in the cold weather operation mode using a PVT module for preheating water provided to the humidifier.

25 . The method of claim 18 , further comprising

depositing the liquid desiccant in a tank;

allowing the liquid desiccant to settle such that the liquid desiccant varies in concentration along the height of the tank; and

drawing liquid desiccant used in conditioning the air stream from the tank at a given selected height of the tank in order to obtain liquid desiccant having a given concentration.