A Community Building Energy Modelling – Life Cycle Cost Analysis framework to design and operate net zero energy communities

Abstract

Despite building codes and standards helping build energy-efficient structures, most focus only on typical individual buildings. Second, they do not discuss community-based renewable energy adoption strategies as part of the standards. However, to facilitate the transition to net zero emissions in the upcoming decades, policies and recommendations from standards must enhance their scope from the buildings to communities and exploit the maximum energy retrofit opportunities available within the community premises. This study proposes a Community Building Energy Modelling – Life Cycle Cost Analysis (CBEM - LCCA) decision-making framework to analyze the techno-economical feasibility of the residential community-wide implementation of any building retrofit scheme. The framework developed is applied in a 14-building residential community in Mumbai, India, to compare the techno-economic benefit of implementing community-wide renewable installations against the existing national Energy Conservation Building Code (ECBC). The results reveal that all the communities together have the potential to generate 333 MWh of electricity per year from solar rooftops alone against the consumption of 369 MWh. The communities are observed to be capable of achieving nearly net-zero energy after adopting a community-wide rooftop solar photovoltaic installation with fewer than eight years of simple payback period (SPP). A thorough sensitivity analysis also reveals that the community rooftop solar strategy proves economically far superior to ECBC compliance of individual building envelopes. Among the retrofits, the roof-wall combination gave the minimum SPP of 8.38 years at a 100 % cooling space fraction. The findings provide evidence for why only a small number of states support ECBC code compliance, and it is recommended that policymakers use the proposed CBEM-LCCA framework to create appropriate energy policies for developing community-wide rather than individual building-level retrofit strategies.