Specific Exergy Costs and Revenues in a Two-Pressure Combined Cycle Plant

Abstract

Paulus and Tsatsaronis presented a method with which specific exergy revenues can be calculated, as opposed to specific exergy costs. In this paper, specific exergy revenues and costs are calculated for a hypothetical two-pressure combined cycle power plant. First, the plant-internal specific exergy revenues and associated exergoeconomic variables are calculated for the case when the product revenues are equal to the product costs. The exergoeconomic, revenue-based variables are then compared to those resulting from the traditional, cost-based methods. The good agreement of the exergoeconomic variables calculated by both methods provides evidence of the validity of the proposed auxiliary equations for calculating revenues. Then, a parametric study with varying product revenues is performed. The resulting exergoeconomic variables show that, for a fixed fuel input, increased capital investment is desired as the products become more valuable.