Evaluation of the effect of a building energy efficiency certificate in reducing energy consumption in Korean apartments

The building energy efficiency certificate (BEEC) is considered an important tool for saving energy in buildings and for reducing greenhouse gas (GHG) emissions in South Korea. To evaluate its effects, data on the site energy use intensity (EUI) of 2,660,159 certified and non-certified apartment units were collected from the Korea National Building Energy Database and compared. The site EUIs for total energy use of the certified apartment units with BEEC levels 1+ and 1 were 1.4–20.2% lower than those of the non-certified apartment units. Particularly, the gas use (for heating) intensity was 3.5–26.4% lower compared to that of the non-certified apartment. However, the electricity use intensity has not decreased despite BEEC because it does not consider the electricity consumption by appliances. In addition, the EUI of the certified apartment units with BEEC level 2 was higher than that of the non-certified apartment units in Group B. These show that the BEEC level 1 or higher contributed to reducing heating energy although its effect was different by climatic regions and the size of apartment units, but its effect on the electricity use intensity was insignificant. It shows that BEEC needs to be improved and some policies are needed to make residential building occupants more aware of the need for them to reduce their electricity consumption and to encourage them to do so.