A Comparative Study of Energy Consumption for Residential HVAC Systems Using EnergyPlus

Samah K Alghoul

doi:10.11648/j.ajmie.20170202.16

Abstract

Energy conservation and sustainability have become an attractive field for research due to the growth in population and continuing search for better living standards. Heating, Ventilation, and Air Conditioning (HVAC) systems account for almost half of consumed energy in buildings and around 10 to 20% of total energy consumption in developed countries. In general, the trend of installing central HVAC systems increases in residential and commercial buildings. In this research, a study of energy consumption of HVAC systems in residential buildings has been conducted with the aim to compare those systems from an energy consumption point of view. The final goal of this research is to reduce energy requirements of residential buildings sector to save energy and reduce carbon emission. A medium size residential building in the city of Tripoli, Libya, was selected as a case study. EnergyPlus building simulation software along with OpenStudio software were used to model the house and HVAC systems. The results show that the virtual component “ideal air loads” used in EnergyPlus is very easy to use, however, its calculated energy consumption is overestimated compared to other models. Therefore, using that component can be misleading and may result in high monthly and annually energy consumption results. The results also show that in a residential building, unitary systems consume the least annual energy consumption compared to other models. It was concluded that variations in energy consumption of the considered HVAC systems decrease as the coefficient of performance (COP) increases and visa verse.

Highlights

One-third of the world’s energy consumption is associated with Buildings [1]
The results presented below focuses on the electricity consumption by the proposed HVAC systems/models
Energy consumption of Unitary and Packaged Terminal Heat Pump (PTHP) models are very close to that of the Ideal air loads whereas high energy consumption resulted in other systems

Summary

Introduction

One-third of the world’s energy consumption is associated with Buildings [1]. Air conditioning systems consume more energy than any other devices used in building services, that was estimated to be about half of the energy consumed in buildings, and between 10% to 20% of total energy consumed in developed countries [2]. Albayyaa et al [10] compared energy consumption for Air Conditioning systems among various residential buildings. Their results show that modern buildings require 53% less energy compared to old buildings. The conclusion of their work is that the software is capable of modeling conventional HVAC systems, there were discrepancies in the results due to differences in input parameters and control strategies. They found that EnergyPlus has more comprehensive component models than the other programs. They used the IDA ICE 3.0 simulation optimize five selected design variables in the building program and the GenOpt 2.0 optimization program to construction and HVAC system

Objectives

Methods

Results

Conclusion