Electricity use trends in New Zealand office buildings, 1990-2008

Purpose - This paper aims to determine trends in office building electricity use in New Zealand. Design/methodology/approach - The research examined Property Council of New Zealand annual operating expense survey data for the period 1990-2008 and identified trends in both electricity expense and consumption per square metre. Findings - Electricity consumption was surprisingly stable over the study period and electricity expenditure per square metre decreased in real terms until very recently. There were some significant differences in the level of consumption between different quality buildings and different locations but the trends were the same. Research limitations/implications - The findings revealed major problems in the accuracy and extent of electricity use data collected. Social implications - Globally the built environment has been assessed as accounting for 40 per cent of energy consumption. While New Zealand generates most of its electricity from sustainable hydroelectric sources, there are limited opportunities to expand such generation. As a result, the NZ government has been promoting energy efficiency as a means to reduce growth in electricity demand. Efficiency policies relating to office buildings have recently been proposed, but few benchmark figures are available on which to base such policies. Originality/value - Little research of this nature has occurred in New Zealand previously and it is necessary to establish benchmarks against which improvements in the sustainability of buildings can be measured. It is also important to identify problems in data collection so that benchmarks are robust.