A hybrid model for ranking CCHP systems with regard to sustainability criteria (Case study: Taleghani hospital)

Rational and efficient energy production and distribution is one of the main issues of sustainable development. ‘’Combined Cooling, Heating and Power (CCHP)’’, has significant environmental benefits by increasing energy efficiency, reducing environmental pollution and consumption of thermal energy from fossil fuels. However, these systems have also higher cost of investment and more maintenance complexity. Therefore, In order to select the best CCHP system, these systems must investigated from the technical and sustainable aspects. In this paper, a hybrid model is developed for selecting and assessing the prime movers of CCHP which is using fuzzy multi criteria decision making (FMCDM), fuzzy TOPSIS method (FTOPSIS) and modified digital logic method (MDL). Thus, fuzzy theory, modified digital logic method and FMCDM model are explained and the various types of prime movers of CCHP systems, including Stirling engines, gas turbines, solid oxide fuel cells and micro-turbines and gas engine are studied according to the objectives of sustainable development and also are compared with a separate production system. To select the optimal system, the proposed decision model is implemented at Taleghani hospital in Tehran regarding to technical, economic, social and environmental aspects and its effectiveness has been analyzed. The results show that the best choice among the alternatives is reciprocating gas engine.