Systems and methods for compressing, storing, and expanding refrigerant in order to supply low-cost air conditioning

A compression unit for a cooling system, comprising:

• at least two pairs of liquid-gas pistons, wherein each pair of liquid gas pistons comprises first and second cylinders having substantially equal volumes, and a combined volume of liquid substantially equivalent to a volume of one of the liquid-gas pistons;
• a pressure equalizing valve arranged between the first and second cylinders of each pair of liquid-gas pistons;
• a liquid pump in fluid communication with each of the four liquid-gas pistons;
• a gas intake valve for low-pressure gas and a gas outlet valve for high-pressure gas arranged at each liquid-gas piston;
• and a series of valves arranged between the liquid pump and the respective liquid-gas pistons, wherein the valves may be alternatively opened and closed such that pressure equalization among each pair of liquid gas pistons, and pressurizing of gas through pumping of liquid through each pair of liquid gas pistons, is performed in a constant time shift.

An expander, comprising:

• a first cylinder, a U-shaped duct, and a second cylinder connected in series,
• wherein the first cylinder is connected to a source of compressed refrigerant and an evaporator;
• wherein the second cylinder is connected to a fluid pump and to a low-pressure fluid reservoir;
• and
• wherein, during expansion of refrigerant, compressed refrigerant enters the first cylinder from the source of compressed refrigerant, and displaces fluid from the first cylinder, duct, and second cylinder to the fluid pump, and, wherein, following expansion of refrigerant, liquid from the low-pressure fluid reservoir enters the second cylinder, duct, and first cylinder to thereby evacuate expanded refrigerant from the expander into the evaporator and refill the expander with fluid.

A method of air conditioning, comprising:

• compressing a gaseous refrigerant;
• storing the compressed refrigerant;
• expanding a volume of the compressed refrigerant with an expansion valve or expander;
• evaporating the refrigerant with an evaporator and thereby causing the refrigerant to absorb heat from a surrounding environment;
• collecting discharged refrigerant vapor from the evaporator;
• and
• conveying the discharged refrigerant vapor to an intake of the compressor, and repeating each of the previous steps.