Advances in Kalina cycle technology (1980-1991). Part 1

The history of thermodynamics has been marked by steady improvements in power plant efficiency. Because the second law of thermodynamics sets an upper limit on the efficiencies of heat engines operating between fixed temperatures, many of the advances have been made by raising the temperature of the heat source. These advances have usually been won by improved materials, by developments in fluid machinery, and by better manufacturing techniques. The second law limit is not attainable because all real power producing processes are thermodynamically irreversible. The only way to increase the efficiency of a cycle with fixed temperature heat source and coolant is to reduce its irreversibilities. This paper presents an example of systems design, guided by thermoeconomic analysis, in producing successively superior structures, each of which takes into account the properties of the working fluid and, in some cases, adjusts these properties. Systems design is illustrated as an iterative decision making process. The steps taken in each iteration are essential to an understanding of the final design. Our experience illustrates the wisdom of the saying, You don't learn to design, you design to learn. Each design inspires new options