Document Type: Original Article
School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran
Institute for Environmental Design and Engineering, University College London (UCL), London, England
Auditing electrical energy in buildings is a feasibility study consisting of a comprehensive assessment of a building's electrical utilities in order to optimize energy consumption. In this paper a bottom-up method to estimate electrical loads is formulated that could help in disaggregating electricity use to specific end-uses in the absence of sub-meters in existing buildings. This method can be used for detailed benchmarking and identification of improvement opportunities. Implementation of the method in an office building, located in Tehran, shows that a satisfactorily match (94.66% for off-peak, 88.69% for mid-peak and 94.46% for on-peak) exists between the calculated loads with the data extracted from electricity bills. The building electrical energy auditing shows a maximum share of consumption for office equipment (32%) and a lower consumption for lighting (28%), space heating and cooling (17%), domestic hot water (12%) followed by catering and other electricity end-uses (11%). Through interpreting the energy auditing results, strategies for increasing energy efficiency has been suggested.