Multi-scale UBEM-BIPV coupled approach for the assessment of carbon neutrality of commercial building stock
Usama Perwez, Keita Shono, Yohei Yamaguchi, Yoshiyuki Shimoda
Abstract
The transitional pathway to carbon neutrality in commercial building stock requires improvement of energy efficiency, use of renewable sources and implementation of non-technological mitigation strategies. However, several methods have been developed to assess the carbon neutrality of commercial building stock but they mainly lack the ability of spatiotemporal quantification of energy demand and decarbonization potential which hinders the evaluation of carbon neutrality at multiple scales. This paper presents a GIS-synthetic hybrid urban building energy model (UBEM) coupled with a physical-based approach of building integrated photovoltaics (BIPV) potential estimation to incorporate a building-level energy model at a large scale that could further evaluate the feasibility of carbon neutrality of commercial building stock at a multi-scale level. As a case study, the proposed coupled scheme is applied to the commercial building stock of Tokyo to evaluate the cofound influence of active and passive design measures, and BIPV on the overall decarbonization potential. The results indicate the following findings: the annual CO2 emissions can be reduced by 84% with the simultaneous implementation of all the measures; focusing on passive design measures is not enough to achieve carbon neutrality in commercial buildings that only contribute 10% of the overall reduction potential; 16% to 40% of the decarbonization potential is contributed by BIPV that is less than efficiency measures; and the scale-bounded comparative analysis shows that total BIPV potential changes in the order of magnitude of 29 to 54 with the variation of scale (with reference to district scale) and 4–16% more self-sufficiency observed at the building-by-building level in comparison to district and city scales. This demonstrates that this coupled approach can provide a purpose-driven perspective for the energy transition of commercial building stock at multiple scales with reduced computational time. Overall, this analysis provides a multi-level perspective to energy modelers and policymakers on how to achieve carbon neutrality in the commercial building stock.