Abstract
The potential to reduce energy consumption in buildings is high. The design phase of the building is very important. In addition, it is vital to understand how to measure the energy efficiency in the building operation phase in order to encourage the right efficiency efforts. In understanding the building energy efficiency, it is important to comprehend the interplay of building occupancy, space efficiency, and energy efficiency. Recent studies found in the literature concerning energy efficiency in office buildings have concentrated heavily on the technical characteristics of the buildings or technical systems. The most commonly used engineering indicator for building energy efficiency is the specific energy consumption (SEC), commonly measured in kWh/m2 per annum. While the SEC is a sound way to measure the technical properties of a building and to guide its design, it obviously omits the issues of building occupancy and space efficiency. This paper studies existing energy efficiency indicators and introduces a new indicator for building energy efficiency which takes into account both space and occupancy efficiency.
Highlights
According to the International Energy Agency (IEA), 9% of the world’s energy is consumed in commercial buildings, contributing a total of 12% of global CO2 emissions, either directly or indirectly [1,2]
That indicator is very precise to measure the technical properties of a building during the design phase, but it does not perform well when the building occupancy and space efficiency are considered in the building operation phase
This study clearly showed that energy efficiency can be measured by using different indicators and it confirmed that different indicators have different impacts on the results showing the efficiency
Summary
According to the International Energy Agency (IEA), 9% of the world’s energy is consumed in commercial buildings, contributing a total of 12% of global CO2 emissions, either directly or indirectly [1,2]. Commission [4] are among the latest organizations to uncover the greatest energy saving potentials in buildings compared to other sectors of the economy. These results were lately further corroborated by the industry’s own findings, published by the World Business Council for Sustainable Development [5]. Concerning commercial buildings a review of studies by U.S Department of Energy [6]. The most commonly used engineering indicator for building energy efficiency—called the specific energy consumption (SEC), commonly measured in kWh/m2 per annum— appears as the most common indicator in the literature reviewed for this study. The higher the occupancy and space efficiency, Energies 2017, 10, 628; doi:10.3390/en10050628 www.mdpi.com/journal/energies
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
