Towards energy-positive and eco-profitable future: a perspective on building-to-vehicle-to-building ecosystems

Globally, sustainable urban development increasingly prioritizes energy-positive and eco-profitable systems. This study examines the emerging building-to-vehicle-to-building (V2B²) ecosystem—an integrated framework extending beyond traditional vehicle-to-grid (V2G), vehicle-to-home (V2H), and vehicle-to-building (V2B) technologies. Given limited direct V2B² empirical evidence, this review develops the first systematic V2X-to-V2B² extrapolation framework incorporating five quantitative assessment criteria with explicit confidence classifications. The analysis examines how V2B² enhances energy system integration, reduces carbon emissions, enhances economic viability, and improves occupant comfort across four sustainability domains. Energy system integration enhancements range from 35-65 % (95 % CI: 41–55 %) compared to conventional grid-tied buildings, with grid electricity usage reductions of 52–77 % (95 % CI: 58–71 %). Economic projections indicate payback periods of 4.2–8.4 years (95 % CI: 5.4–7.2 years), while carbon reduction potential ranges from 38-83 % (95 % CI: 42–63 %) depending on regional grid carbon intensity and renewable energy penetration. The review explores challenges and opportunities associated with scaling V2B² implementation, examining technological advancements, policy frameworks, infrastructure requirements, and consumer demands. Critical limitations include predominance of simulation-based findings (78 % of studies) and limited geographic scope. This study establishes replicable methodology for emerging technology assessment under data scarcity, providing transparent framework for evidence-based decision-making while maintaining scientific rigor through explicit uncertainty quantification.