India's green startup ecosystem has grown rapidly since 2016, yet no cross-sectoral, comparative Business Model Canvas (BMC) analysis of this cohort exists. This study applies the nine-block BMC and Triple-Layered Business Model Canvas (TLBMC) to five Indian green sectors — clean energy, electric mobility, waste management, sustainable agriculture, and green packaging — using exclusively freely accessible secondary sources: public portals, media archives, open-access academic publications, and company disclosures. Drawing on documented cases including Phool, Ather Energy, Fasal, Oorjan Cleantech, and others, the study maps common business model patterns, traces documented strategic pivots, and identifies scalability mechanisms and constraints. Findings reveal three recurring BMC archetypes, a dominant pivot trigger pattern centred on regulatory and supply shocks, and a persistent growth-stage capital gap that constrains scalability. The paper proposes a preliminary India-Specific Green Startup BMC Framework and offers implications for entrepreneurs, investors, DPIIT, and SIDBI.