Techno-economic Assessment of Retrofitting Heating, Ventilation, and Air Conditioning System – Case Study

Abstract

Retrofitting heating, ventilation, and air conditioning (HVAC) systems in existing buildings and applying energy-efficient technologies can significantly reduce energy consumption and greenhouse gases emissions. In this work, two options of HVAC retrofitting were proposed and discussed for the existing heating system of school of engineering at the University of Jordan as a case study. The experimental tests showed that only one of the three diesel boilers work normally while the other two boilers are not efficient, with actual efficiency of 25%. The first retrofitting was to upgrade the existing heating system to a liquefied petroleum gas (LPG) boiler system with estimated annual saving of 29,757 Jordanian dinar (JOD), and a payback period of 3.9 years. The second option for retrofitting was a new HVAC system for the building including heating and air conditioning with a variable refrigerant flow (VRF) system and heat pump chiller. The estimated cost showed that the VRF system was the lowest one in running cost in winter. The diesel boilers had the highest greenhouse gas emissions with an average value of 377.3 tons of CO2 per year, while LPG boilers achieved the second highest emissions of around 279 tons of CO2 per year, whereas the heat pump chiller in winter produced 199 tons of CO2 and the VRF system emitted 180 tons in winter. The LCCA economic analysis was performed for the proposed systems, showing that the LPG boilers system was more feasible than the diesel boilers system, while the VRF system was more feasible than the heat pump chiller system