ABSORPTION EQUIPMENT FOR ENERGY SAVINGS: A CASE STUDY IN SICILY

Abstract

This paper considers a feasibility study on the recovery of the reject heat available from an electric utility with two units operating with 120-MW gas turbines; these units have a heat recovery system that feeds the district heating pipeline of an industrial consortium. Thus, feeding the expeller of the absorption equipment installed in a cooling plant for foodstuff stocking represents an opportunity for the feasibility study. This plant operates at both 0 °C and -18 °C. The feasibility study covers two aspects: (1) the technical feasibility of a suitable absorption cooling plant that uses two separate pieces of absorption equipment working with the pair ammonia-water and (2) the relevant economic venture analysis. The feasibility study pertains to both the optimal design of the absorption equipment and the energetic and exergetic analysis of the plant; moreover, the same type of analysis was performed for a reference case pertaining to a two-stage reciprocating compression refrigerating plant. An economic analysis of the venture demonstrated that the expected time of return on the differential investment is less than 4 years and that the specific investment costs expected given the differential costs between the two alter- native options are 11.28 €/toe of primary energy savings and 15.84 c€/t(CO2,eq) of reduced greenhouse gas emissions.