Development of numerical trigeneration system cascade analysis with transmission and storage energy losses consideration

Abstract

Depletion and rising prices of fossil fuel, as well as environmental pollution, have led the world to find energy-efficient technologies such as improvement of efficiency of the current energy systems. The thermal efficiency of the current systems can be improved from 30 - 40 % to 80 - 90% through implementation of trigeneration system. Trigeneration is a system which can improve the efficiency of the current energy systems by reusing the waste heat to produce power, heating and cooling from a single fuel. Pinch Analysis is a methodology which enables users to optimize the energy, water and other resources. Trigeneration System Cascade Analysis (TriGenSCA) is developed to minimize power, heating and cooling energies as well as obtain optimal sizing of the trigeneration system. In the previous TriGenSCA, transmission energy losses which contribute significantly to the final amount of energy arrived at the demand was not considered. This leads to an optimistic target for energy reduction. The objective of this work is to develop an extension of numerical insight-based Pinch Analysis methodology for optimal trigeneration system which considers energy losses in the transmission lines and storage systems. There are three major steps on developing TriGenSCA, which are data extraction, construction of TriGenSCA with transmission and storage energy losses, and comparison of TriGenSCA with and without transmission energy losses consideration. The transmission energy losses are included in the TriGenSCA where energy depleted due to the transportation of energy from the trigeneration system to the demand load, separated by 10 km of distances. Aluminium cable steel, carbon and stainless steel pipelines are used to transfer power and thermal energies to the demands. Based on the case study, the energy difference of TriGenSCA with and without transmission energy losses is 76.83 MWh/d. This shows huge energy is lost due to the transmission process. The development of this systematic methodology can give benefits to engineers, designers and power plant managers in order to determine the exact value of utility and thus, perform the optimal design of a trigeneration system.