Vapor cyclic refrigeration methods and systems are either 1. Vapor-compression refrigeration; 2. Vapor-absorption refrigeration (no compressor); or 3. Vapor-adsorption refrigeration (no compressor)
In adsorption refrigeration, the refrigerant or adsorbate vapour molecules adsorb onto the surface of a solid instead of dissolving into a liquid. While in an absorption system, an absorber absorbs the refrigerant vapour into a liquid. Adsorption refrigeration also includes a generation process where refrigerant vapour molecules desorb from the solid.
A variant of Vapor-absorption refrigeration is the Electrolux Refrigeration is also known as Domestic Eloctolux refrigeration or sometimes known as Three fluid Refrigeration as it uses three fluids for the cooling process which are ammonia, water and hydrogen. Hydrogen gas is used to increase the rate of evaporation and hence rate of cooling. No pump or compressor is used.
The absorption cycle is similar to the compression cycle, except for the method of raising the pressure of the refrigerant vapor. In the absorption system, the compressor is replaced by an absorber which dissolves the refrigerant in a suitable liquid, a liquid pump which raises the pressure and a generator which, on heat addition, drives off the refrigerant vapor from the high-pressure liquid.
Some work is needed by the liquid pump but, for a given quantity of refrigerant, it is much smaller than needed by the compressor in the vapor compression cycle. In an absorption refrigerator, a suitable combination of refrigerant and absorbent is used. The most common combinations are ammonia (refrigerant) with water (absorbent), and water (refrigerant) with lithium bromide (absorbent).
Adsorption refrigeration was invented by Michael Faraday in 1821, even though the basis of artificial modern refrigeration dates back to 1748 with William Cullen experiments. Adsorption refrigeration technology has been extensively researched in recent 30 years because the operation of an adsorption refrigeration system is often noiseless, non-corrosive and environment friendly.
In the early years of the twentieth century, the vapor absorption cycle using water-ammonia systems or LiBr-water was popular and widely used, but after the development of the vapor compression cycle it lost much of its importance because of its low coefficient of performance (about one fifth of that of the vapor compression cycle).
Absorption refrigerators are a popular alternative to regular compressor refrigerators where electricity is unreliable, costly, or unavailable, where noise from the compressor is problematic, or where surplus heat is available (e.g., from turbine exhausts or industrial processes, or from solar plants), and in recreational vehicles that carry LP gas. It is also used in industrial environments where plentiful waste heat overcomes its inefficiency.
So, Why we Waste Car Radiators Heat Instead of Using it for Air-conditioning? The heat energy in car radiators could eliminate the need for compressors and be used in the generator process in Vapor-absorption or Vapor-adsorption systems for car air-conditioning.
It is better to utilize cars engines surplus heat using adsorption/ absorption systems low efficiency rather than waste energy into air, and using more energy to run compressors.
Not only the World wastes cars’ heat but also consumes huge energy in air-conditioning and refrigeration in too many countries having high solar heat by using compression refrigeration