Recommending a thermal energy benchmark based on CIBSE TM46 for typical college buildings and creating monthly energy models

According to Chartered Institution of Building Services Engineers, CIBSE TM46 benchmarks, a typical college building needs 240 kWh/m2 thermal energy annually. This paper firstly analysed the accuracy of the CIBSE TM46 'University Campus' benchmark against the thermal consumption values displaying on Display Energy Certificates (DECs). The DECs of 52 typical college buildings in Dublin were assessed and based on the 46% discrepancy between the median of samples and the CIBSE benchmark a new benchmark of 130 kWh/m2/yr was recommended. Secondly, monthly thermal energy models (MTEMs) which take into account the variations of heat demand during a year were generated. MTEMs were created using five key factors, including the mixed use method, CIBSE UC recommended benchmark, activities area, heating degree days, and typical operational hours of heating systems. The high level of accuracy of MTEMs was assessed against the actual consumption. The developed methodology predicts an accurate and detailed estimation of monthly thermal energy consumption in typical college buildings. In addition, a new definition for typical college buildings which is a mixed use building including seven major activities is presented.