Absorption Cycle Heat Pump Integration for Locally Integrated Energy Sector

Abstract

Energy losses in daily life has caused energy inefficiency whereby contributed to serious environment impacts such as carbon emission, greenhouse effect and global warming. The increasing of greenhouse gases emission and crude oil usage have become a main focus to improve world energy efficiency. In order to minimizing the emissions and environmental pollution, Process Integration (PI) through Pinch Analysis (PA) is used to increase the energy efficiency. Total Site Heat Integration (TSHI) is integrated several processes with the centralized utility system. TSHI is extended to Locally Integrated Energy Sectors (LIES) whereby it provides energy integration with end users from various sectors such as the industrial, services, residential, agriculture, transportation and public sectors within a local area, as well as the integration of renewable energy sources. In order to handle the intermittent steams, energy storage is proposed for recovering energy across time period. In this study, waste heat recovery system by using absorption cycle heat pump is highlighted. Two types of absorption cycle heat pump such as absorption heat pump (AHP) and absorption heat transformer (AHT) are used to integrate with LIES utility system to maximize the energy recovery. This new methodology deals with the amount of AHP and AHT heat generation from the enthalpy of working fluid pair in water-lithium bromide with heat storage system in LIES. An illustrative case study is performed for demonstrating and verifying the proposed framework, whereby waste energy recovery opportunities are found from the system studied. Economic analysis on payback period is also performed to compare with the system with and without usage of AHP and AHT. This developing methodology provides a better guidance to engineers especially during the design stage on the performance limitations and specific compromises within a system. At the end of this research, cost saving is achieved, a shorter payback period than existing system and overall energy efficiency is improved within heat storage system for LIES by adding in the absorption heat pump cycle.