Multi-scale smart management of integrated energy systems, Part 1: Energy, economic, environmental, exergy, risk (4ER) and water-exergy nexus analyses

A holistic analytical approach is proposed to study the performance of fossil fuel burning integrated energy conversion systems considering energetic, economic, exergetic, environmental and risk (4ER) aspects in a framework. For this, life cycle assessment is conducted to study environmental impacts while other analyses are performed using the algebraic thermo-mathematical programming. The hazardous risks are also investigated using a hazard and operability approach. The external hot and cold utilities are also studied using a novel water-exergy nexus (WExN) analysis. Accordingly, two configurations are developed that integrate a Rankine cycle (RC) and an ejector refrigeration cycle (ERC) for two purposes: power and cooling co-generation (CGS) and power generation (MGS). Water losses in both systems are studied considering three cold utilities and two fossil fuel cycles using the WExN analysis, and the performance of the CGS and the MGS are compared employing several organic fluids. The results showed that the MGS had greater energetic and exergetic efficiencies, better environmental performance, and less hazardous risk impacts compared to the CGS employing almost all working fluids. The smallest exergy loss in the cooling system was 3.90 MW and 7.94 MW in the MGS allocating R123 and the CGS using R718, respectively.