Optimal Energy Allocation of Net-Zero Energy Building

For a microgrid with flexible modes of operation in net-zero energy building (NZEB), a systematic scheme, from design to realization, is proposed. According to climate information and load demand, an optimal allocation algorithm is proposed to ensure both reliability and economy. Then, a two steps design including PVsyst energy balance and HOMER economic optimization is adopted to verify that energy allocation algorithm. The feasibility of the design scheme of the NZEB is verified by comparing actual operation data with simulation data of electricity consumption and generation. This system can operate in either grid-connected or islanded mode, and is able to seamlessly transfer from one to another. The proposed procedure provides an optimal solution to a PV system in microgrid in NZEB in early design phase, and is useful for final decision-markets such as construction managers or contractors.