This paper is concerned with commercially available absorption units and their application to solar collector systems. Interest in these heat power chillers has been increasing steadily because of the energy shortage and the rapidly rising energy costs. Many papers have been presented previously at solar conferences and workshops. These have generally been the result of projects originally funded by the National Science Foundation. Of the many absorbent refrigerant combinations that have been studied, only the ammonia water and the lithium bromide water combinations have been commercially successful. Most of the previous papers have been based on these absorbent refrigerant combinations and have concluded in general that the lithium bromide water cooled unit is the more logical choice for use on solar systems. Generally, the ammonia water with some cycle variations requires higher heat source temperatures than are available with flat plate collectors. If the costs of concentrating collectors are reduced, then this system may be more attractive.

This paper will deal specifically with a water cooled aqueous lithium bromide unit.