The basic principle of a solar air conditioner is similar to a propane fridge, heat is used (from the solar vacuum tubes) to heat up a cooling liquid. The hotter this liquid gets the better the performance.
Under a normal AC a low boilling temperature gas (refrigerant) is compressed to a high temperature around 170 F by an electrical compressor. It is then and passed through a condensor coil where about 2/3 down the coils it changes from a gas to a partialy saturated gas (liqud). This partial liquid is then sent to an Expansion coil (evaporator) where it looses its pressure and a phase change occurs back to a gas. This phase change takes away heat with it causing the cooling effect on these coils and air is then blown over the coils to produce cold air. Solar Air Condtioning works the same as any air condtioner in this cooling phase change. However it before it passess to the condensor, it 1st passes through special vacuum tube collector that heat the gas up even further to about 350 F.
This hotter gas is passed through the Solar Air conditioner'sconsensor and as such starts its phase change much earlier in the 1st 1/3 of the coil. By the end of the coil it is almost completely liquid versus the partially saturated gas in a regular A/C. The added efficiency from the solar vacuum tube collectors allows the refrigerant to work more efficiently with no additional moving parts or motors. This increases the ability of the gas to change back into a liquid much quicker and dramatically reduces the energy requirement of the compressor. The gas now condenses back into saturated gas in the first third of the condensing coil not the final third. Therefore by the time the refrigerant reaches the expansion devise in the inside coil, it is already almost a liquid. This allows the near liquid refrigerant to be more efficient at absorbing heat, making it 5-6 degrees cooler in the inside coil, delivering colder, drier air to the building. Refrigerant Type - 407c or 410.
