Small-Scale Industrial Cogeneration: Design Using Reciprocating Engines and Absorption Chillers

Abstract

This paper describes a packaged cogeneration system designed for light industrial applications (i.e., situations where a user wants a maximum of 1 MW of cogenerated electricity). The design employs reciprocating engines fueled with natural gas or liquid fuels. Waste heat from the engine exhaust and jacket water is used to drive an absorption chiller. This approach yields a variety of unique advantages, including: (1) ability to satisfy the needs of facilities that have a low ratio of thermal-to-electric energy needs, and which have significant refrigeration loads, and (2) the ability to provide greater operating efficiency in the <1 MW size range, especially at part load, when compared to systems based on gas turbines or steam turbines. Although component substitution can be used to vary the energy output capabilities of the system, the discussion focuses on a unit having an electrical rating of 418 kW and cooling capacity of 160 tons. This paper discusses component selection, operating parameters, economics, maintenance issues, and other factors.