Title A Comparative Analysis on the Energy Mix Performance of Zero Energy Building (ZEB) Grade 5 Multi-Family Housing by Building Energy Model
Authors 김경욱(Kyungwook Kim) ; 함남혁(NamHyuk Ham)
DOI https://doi.org/10.5659/JAIK.2026.42.4.293
Page pp.293-304
ISSN 2733-6247
Keywords Zero Energy Building; ZEB; ECO-2; DesignBuilder; EnergyPlus; Geothermal; Heat Pump; Solar PV
Abstract This research evaluates the energy independence performance of multi-family residential buildings classified as ZEB Level 5 under different renewable energy mix scenarios. Using both the quasi steady state based ECO-2 program and the dynamic simulation tool DesignBuilder (EnergyPlus engine), models were constructed for district heating, geothermal, and photovoltaic (PV) systems. A baseline model without renewable energy was first calibrated to achieve less than ±5% deviation in annual and primary energy consumption between the two programs. Subsequently, energy-mix scenarios combining geothermal and solar systems were simulated to assess each source’s contribution to total primary energy reduction. The results indicate that higher shares of geothermal heating and cooling systems lead to greater primary energy savings, even under identical ZEB 5 requirements. DesignBuilder estimated PV-related savings to be about 10.9% lower, whereas geothermal savings were estimated to be about 27.8% higher than those calculated by ECO-2, likely due to differences between static and dynamic analysis algorithms. These results indicate that incorporating dynamic simulation models capturing actual operational characteristics can improve the reliability of renewable-energy evaluations in Korea’s ZEB assessment framework.