Sweetening the absorption option

Today’s single-stage absorbers can generate chilled water from hot water as low in temperature as 190°F.
By Gas Technology August 12, 2016

Single stage absorption chillers are available in sizes from 50 tons to several thousand, and can be designed to generate chilled water from relatively low inlet temperatures. Courtesy: Broad U.S.AEspecially in institutional applications, it may also make sense to use recovered heat, perhaps from a boiler economizer, to supply energy for a single-stage absorption chiller. This unit could supplement an existing chiller plant to provide chilled water at an operating cost much lower than an electric chiller in the warm months, or even year-round. Today’s single-stage absorbers can generate chilled water from hot water as low in temperature as 190°F.

Even if the temperature of the recovered heat stream is not this high, it could very effectively reduce the cost of the heat input to either a hot water or steam absorption chiller. Again, it’s important to balance the cost of adding absorption chiller capacity versus the reduction in operating costs. If you already operate a hot-water chiller, the payback from streaming hot water with recovered heat could be very attractive.