Abstract
Integrating photovoltaic (PV) systems into modern building facades is a critical step toward sustainable architecture, allowing buildings to serve as energy generators without compromising aesthetic value. There is a notable absence of analytical methods that systematically relate facade design features to their potential for PV integration, limiting design efficiency and innovation. This study aims to extract design grammar from modern architectural facades using Analytical Shape Grammar (ASG) to serve as a foundation for developing future facade designs compatible with PV panel integration. A set of facade examples is selected based on four key criteria: (1) alignment with modern architectural style, (2) compatibility with existing PV panel specifications, (3) adaptability across various facade levels and positions, and (4) presence of repetitive motifs with geometric variations aligned with PV module dimensions. Each design was visually analyzed to identify initial shapes and transformation operations, resulting in the derivation of shape rules based on Shape Grammar (SG) principles. The analysis yields a structured grammar library comprising 14 initial shapes and 65 transformation rules, organized into 11 rule application scenarios. These components form a systematic vocabulary for generating PV-ready facade compositions, ensuring formal compatibility with PV module dimensions and modular patterns while maintaining modern architectural coherence. The grammar library provides a structured and reusable framework that can inform rule-based PV-oriented design workflows, enabling architects to generate energy-efficient and stylistically consistent facade designs grounded in modern architectural principles.