Energy performance evaluation of a plus energy house based on operational data for two years: A case study of an all-electric plus energy house in Korea

Abstract

The concept of zero-energy buildings is gaining much interest, and its technical feasibilities have been demonstrated for sustainable development. Although several case studies present how effectively zero-energy performance can be achieved, there is still a lack of data understanding adopting different combined passive and active systems for zero-energy performance. In response to this gap, this study introduces new integrated systematic approaches of enabling all-electric zero-energy performance and presents these features and operating performance for each part of energy consumption contributors based on measured data over two years. Structural insulation panels, vacuum glazing with heated glass were applied as passive techniques. An air-source heat pump and package air conditioner were used for heating and cooling systems, respectively. In addition to the passive and active systems, building-integrated solar thermal and roof-integrated photovoltaic (RIPV) systems were installed to offset all the remaining energy in the house. The energy use intensity of the house was 77.98 kWh/m2·yr; heating and domestic hot water had the highest consumption. To save cooling consumption, exterior electric venetian blinds and natural ventilation were used to cut down energy consumption. The house consumed 7,368.95 kWh/yr and produced 11,439.68 kWh/yr through the RIPV, the annual RIPV surplus accounting for 35.58 % of the annual energy production. The results from this case study provide a comprehensive overview of the feasibility of different combined technologies and insights into proper design strategies to improve the performance of zero-energy houses and buildings from another point of view.