Robust optimal design of renewable energy system in nearly/net zero energy buildings under uncertainties

It is acknow ledged that the conventional design methods can easily lead to oversized system or unsatisfactory performance for different design conditions. M ost existing studies on design optimization of net zero energy building( nZ EB) are conducted based on deterministic data / information. How ever,the question is: How is the actual performance of a design nZ EB in different years considering uncertainties? This study,therefore,proposed a robust design method for sizing renew able energy systems in nZ EB concerning uncertainties in renew able resources and demand load. The proposed robust design method is applied tothe planning of renew able energy system for the Hong Kong Zero Carbon Building. The annual performance of nZ EB under the optimal design options are systematically investigated and compared using the proposed robust design method and the deterministic method. It is meaningful to obtain a fitting formula to identify the relationship betw een the probability of achieving annual zero energy balance and the design mismatch ratio. On the basis of M onte Carlo uncertainty propagation methods, the uncertainty of nZ EB performance is quantified w hich provides flexibility for designers in selecting appropriate design options according to the required probability of achieving nZ EB during the design stage.