Sensitivity analysis of macro-parameters in the system design of net zero energy building

The rapid growth of building energy has imposed increasing pressure on environmental protection. Net zero energy building (NZEB) is widely considered to be an effective solution. Various macro-parameters in a NZEB have different impacts on system design and very few studies have investigated such impacts in a NZEB. Therefore, a systematic sensitivity analysis of macro-parameters in a NZEB has been conducted in this study. Differential sensitivity analysis, a local sensitivity analysis method, is performed on a constructed dynamic simulation platform to study the impacts of each macro-parameter on the sizes of key NZEB systems. The systems include heating, ventilation and air-conditioning (HVAC) system, renewable energy system and energy storage system. The influence coefficient of each parameter is calculated to quantify its sensitivity impacts. Meanwhile, an exhaustive search approach is proposed to minimize the overall initial investment cost of the renewable energy system and storage system. The study results are valuable to help designers improve NZEB system design through carefully selecting more accurate design parameters especially those identified with heavy sensitivity impacts. The study also provides a method to optimize the initial investment cost of systems in a NZEB.