Measurement and verification analysis on the energy performance of a retrofit residential building after energy efficiency measures using RETScreen Expert

Korean old residential apartments built over many decades were constructed without proper energy efficiency measures. This makes the energy performance of existing buildings to be very poor when compared with the energy performance of new buildings. This study presents the use of a 12 years gas consumption data to evaluate the energy performance of an existing residential building in Korea by carrying out Measurement and Verification (M&V) analysis using RETScreen Expert software after building retrofit. From the analysis, a total of 249 Giga Joules (GJ) of Liquefied Natural Gas (LNG) was consumed at the rate of 0.17 GJ/day on an average from the year 2011 to 2014 with the peak consumption in the year 2013 costing the occupant a sum of $5,401. Also, the net energy savings was 64GJ as of June 2019 after the installation of an Energy Conservation Measures (ECMs) with the highest between the year 2016 and 2018. An energy forecast for the year 2020 indicates that 2.71 (tCO₂) GHG emissions will be reduced as a result of the energy that will be saved from the 54 Giga Joule (GJ) fuel consumed. Finally, energy efficiency was attained and this reduced the resident doubt on the benefits of energy efficiency measures.