Energy benchmark for naturally ventilated medium-sized supermarkets
Supermarkets are responsible for more than 12% of the total electricity consumed by the commercial sector in Brazil. However, studies still need to be done to establish typical consumption in this typology, and the development of energy benchmarks can help fill this gap. Two approaches to creating benchmarks are usually used: top-down and bottom-up. This research aimed to compare distinct approaches to create an energy benchmark for the typology of medium-sized and naturally ventilated supermarkets in Brazil's Southeast region. The methodology comprised two case studies, the development of a representative model, the development of a parametric database containing energy consumption data and the comparison between the two approaches. The parametric simulations generated a database with 1536 models from which the most influential parameters in the bottom-up approach were identified through a sensitivity analysis, and a percentile analysis was performed for the top-down approach. The bottom-up approach showed that the construction variables and the weather have a minor influence on energy consumption. The limits for the typical EUI (benchmark) were similar for both approaches, but the bottom-up showed aspects of energy use that cannot be identified in the top-down. Thus, it was confirmed that the bottom-up approach is more costly but allows studies and conclusions about the building performance and the singularities of the typology, while the top-down approach does not create detailed information. The choice of approach should consider the reference knowledge of the building stock.
Keywords: Energy efficiency, benchmarking, supermarket.