Ejector Refrigeration

Ejector refrigeration is a cooling method that uses a jet of high pressure steam or another vapor flowing through a nozzle to create a low pressure region that draws refrigerant vapor from an evaporator, replacing the mechanical compressor used in a conventional vapor compression system. Because the ejector has no moving parts, the approach can run on waste heat or solar heat rather than electricity to drive the cycle, which has kept it of interest for low cost cooling where cheap heat is available but electricity is expensive or unreliable. It was used commercially for building air conditioning and refrigeration in the early twentieth century before more efficient electric vapor compression systems took over, and it remains an active area of research for waste heat driven cooling.