Net Zero Energy Public: proposal for a method to transform public buildings into Net Zero Energy

Abstract

Climate change and the energy crisis are major global challenges today. Among the economic sectors, the building sector stands out because of its higher energy consumption and CO2 emissions than other sectors. In this sense, it is necessary to implement measures that promote energy efficiency and the use of renewable energy sources to reduce the energy consumption of these buildings. Net Zero Energy Buildings (NZEB) are emerging as a promising alternative. Although the focus of NZEB studies and applications is on reducing energy consumption in new buildings, existing buildings offer greater opportunities for energy savings. The public sector, on the other hand, represents a significant share of energy consumption, and its efficiency can result in reduced public expenditures, thus reducing its impact on society. In this context, this study proposes a methodology to transform existing public buildings into Net Zero Energy Buildings (NZEB) in the Brazilian context, using the Design Science Research (DSR) research methodology. The proposed method, called Net Zero Energy Public (NZEP), is composed of five macro-steps unfolded in 25 micro-steps, which considers from the selection of the building to be transformed to the measurement and verification of the transformation results. The proposed methodology was evaluated and validated by experts in NZEB and DSR and applied in two transformation projects in Brazilian public buildings, demonstrating its effectiveness in reducing energy consumption and operating costs in the sector. The results show that NZEP can support the transformation of existing public buildings by integrating NZEB concepts with INI-C assessments. The proposed methodology can help promote the research and transformation of the Brazilian public building stock to NZEB standards. In addition, it can help accelerate the efficiency and labeling process of the segment, resulting in reduced energy consumption and operating costs for the sector.