Simple Economic Model for Solar Cooling and the Potential for the ICPC Collector

A simple model to analyze the economic viability of solar absorption cooling systems is presented. A given system and application can be characterized by a single figure of merit, V, defined as the ten-year cumulative value of the solar cooling provided (in dollars per square meter). To quantify this description, the model introduces five dimensionless parameters, all of order unity. Thesedescribe 1) the solar availability for a particular collector type in a particular location, 2) the collector performance (annual thermal efficiency), 3) the prevailing cost of electricity, 4) the performance of the absorption chiller and 5) the performance of the vapor compression chiller whose cooling is being displaced. The quantity, V, is then the product of a constant Vo and these fivedimensionless quantities. As a rule of thumb, the initial cost of any collector system plus the cumulative ten year maintenance costs should be less than V. The constant Vo depends only on conversion factors and representative normalization quantities and is equal to $380/(m2-10 years). For purposes of illustration, this figure of merit, V, is determined for four different 'generic' collectortypes (flat plate, evacuated flat fin, integrated CPC, and parabolic trough) in three difference locations (Phoenix, Boston, and Miami). The implications of the variations of this quantity, along with the relatively low value of Vo are discussed.