Optimising energy use in an existing commercial building: a case study of Australia\u2019s Reef HQ Aquarium

Sascha Thyer,Michael Ridd,Severine Thomas,Craig Mcclintock

doi:10.1007/s12053-017-9556-x

Abstract

Reef HQ Aquarium is a major tourism attraction in tropical North Queensland, Australia. In 8 years, a 50% reduction in grid electricity was achieved through targeted infrastructure investment, whilst growing the business. Initially, grid energy consumption was 2438 MWh per annum, with 490-kW peak demand and energy intensity of 1625 MJ m−2 year−1 used on typical equipment such as HVAC (heating, ventilation and air conditioning), machinery, lighting and catering equipment. Savings of 13% were achieved in the first year by increasing indoor air temperature set-points by 1.5 °C with no significant costs or impacts on occupant thermal comfort or worker productivity. Peak demand was decreased by 46% by upgrading the computerised building management system (BMS), HVAC, machinery and lighting; and by installing a 206-kW photovoltaic (PV) solar power system. This case study illustrates that (a) significant energy use reductions are possible at low cost; (b) capital investment in energy-efficient infrastructure can have short payback times and high direct and indirect benefits, particularly where equipment is ending its life. This study is unique as it examines how a commercial building with integrated chilled water thermal energy storage (TES) and a 3.2-ML chilled seawater aquarium system can be controlled by a BMS to optimise solar power to manage peak energy demand and also increase the utilisation of generated PV power in the absence of electrical battery storage. An interesting building is used to demonstrate efficiency methods with elements such as HVAC and lighting which usually consume over half commercial buildings’ energy use.

Highlights

In developed countries, the buildings sector uses between 20 and 40% of final energy consumption (Perez-Lombard et al 2008)
This work aims to bridge the gap between the demonstration of new energy efficiency models in scientific settings, and energy efficiency retrofit measures applied by an owner/manager in a real-world setting which takes into account the practicalities of an ageing commercial building and resourcing for retrofit actions
The objective of this study is to examine the efficacy of the methods used for a comprehensive energy efficiency retrofit undertaken over many years by a commercial building owner/manager

Summary

Introduction

The buildings sector (residential, commercial, and public) uses between 20 and 40% of final energy consumption (Perez-Lombard et al 2008). In Australia, the buildings sector represents approximately 23% of Australia’s total greenhouse gas emissions (Australian Sustainable Built Environment Council 2008). There is evidence that energy efficiency can have a positive effect on economic growth (Vivid Economics 2013) and reductions in commercial buildings energy use represent an opportunity to reduce global greenhouse gas emissions (Pitt and Sherry 2014; Levine et al 2007). Total energy consumption within the Australian economy has been falling since 2011–2012 despite a growth in the economy, in part due to increases in energy efficiency (Department of Industry and Science 2015). This work aims to bridge the gap between the demonstration of new energy efficiency models in scientific settings, and energy efficiency retrofit measures applied by an owner/manager in a real-world setting which takes into account the practicalities of an ageing commercial building and resourcing for retrofit actions

Objectives

Methods

Results

Discussion

Conclusion