The aim of exergy-based methods in energy conversion plants is to identify important interrelationships (for example, among thermodynamic performance, investment costs and environmental impact, or among important plant components) and to supply vital information for system improvement from the thermodynamic, economic and environmental viewpoints. The information obtained through exergy-based methods cannot be supplied by any other method and assists the engineer’s knowledge, experience, and creativity.
The so-called exergoeconomic and exergoenvironmental analyses pinpoint the magnitude, sources and causes of thermodynamic inefficiencies and allow for the quantification of the costs and environmental impacts associated with these inefficiencies. These analyses are conducted at the plant component level and, on one side, allow a comparison of the investment costs with the costs associated with thermodynamic inefficiencies (exergoeconomic analysis) and, on the other side, a comparison of the environmental impact associated with the construction and operation of a component (exergoenvironmental analysis). Exergy-based methods provide a uniform, consistent and integrated tool for simultaneously evaluating the thermodynamic performance and the cost and environmental impact associated with the final product(s) of an energy conversion plant.
At the Chair of Energy Engineering and Environmental Protection we work on the further development of the so-called advanced exergoeconomic and exergoenvironmental analyses. In these advanced methods, exergy destruction, costs, and environmental impacts associated with each component are categorized based on whether they are endogenous or exogenous as well as avoidable or unavoidable. An advanced evaluation only uses the avoidable endogenous and the avoidable exogenous thermodynamic inefficiencies, investment costs and component related environmental impacts and identifies (a) the interdependencies among plant components and (b) the potential for improvement for each component and the overall plant.
Exergoeconomic and exergoenvironmental analyses were conducted for a variety of different processes and plants that provide electric power, hydrogen, heat and cold, as well as for energy-storage processes and energy-intensive chemical processes. Our research group is one of the leading groups in this field internationally.