A Methodology for Screening Office Buildings for Energy Retrofit Measures

Abstract

Both private and public sectors own and operate an array of office buildings that consume energy and contribute to the emission of greenhouse gases. In an attempt to reduce energy demands, an analysis into the cost/benefit relationship of incorporating energy retrofit measures (ERMs) was carried out. The main objective was to develop a methodology for screening office buildings for both their current level of energy efficiency and their potential for retrofit applications. Optimal retrofit options can be determined by examining how different building characteristics affect the benefits received from improving various components. By characterizing the office building stock into a manageable set of representative models, it was possible to make estimations on energy consumption for lights, computers, pumps, fans, hot water supply, cooling and heating loads. Employing EnergyPlus, an energy modelling software package, these representative building models were analyzed using three different climate regions for the specific effects that altering building components have on energy consumption. Using a statistical regression analysis, a set of equations was derived for determining the energy consumption based on building-specific variable values. A life cycle cost analysis was used to obtain the net present value associated with the implementation of various retrofit ERMs. Payback period was adopted to quantify the cost effectiveness of ERMs.