Effect of building energy efficiency certificate on reducing energy consumption of non-residential buildings in South Korea

An accurate understanding of the effect of energy efficiency policies is a key to achieving national goals. This study aims to analyze the effects of building energy efficiency certificates (BEEC) using the data on 222,813 non-residential buildings in the Korea national building energy database. First, the actual source energy use intensities (EUIs) were compared with the simulated source EUIs of certified buildings. The actual source EUIs were larger than the simulated source EUIs, and the difference became greater as BEEC level rose. For instance, the gap was 15.5% in buildings with BEEC level 2 in the central region, whereas it was 63.0% in buildings with BEEC level 1++. Second, the source EUIs of certified and noncertified buildings were then compared, revealing that the source EUI for heating energy of certified buildings was 33.8% to 58.1% smaller than that of non-certified buildings. This suggests that BEEC contributes greatly to reducing heating energy usage. However, the source EUI for baseload and cooling energy consumption was larger in buildings with BEEC level 1 and 2 than in non-certified buildings. The result shows that a significant amount of energy that cannot be taken into account in the scope of BEEC is being used in non-residential buildings. Nevertheless, there was an apparent decrease in the source EUI for the certified buildings with BEEC level 1 + or higher. This indicates that in buildings with BEEC level 1 + or higher, energy saving technologies offset the increased baseload and cooling energy and are effective at reducing energy consumption. This in turn suggests that it is appropriate for the government's plan to require all buildings with a gross floor area of more than 1000 m(2) to obtain a BEEC level of 1++ or higher from 2025. (C) 2021 Elsevier B.V. All rights reserved.