Fuente: WIPO "sustainability" The invention provides a smart building model (104) for calculating real-time global sustainability score and forecasting global sustainability score of an entity (102) with buildings at multiple geographical locations. The smart building model (104) comprises a data acquisition module (214) that acquires data from a plurality of sensors that monitor data of assets associated with each building. A key performance indicator (KPI) module (216) assess KPIs based on data acquired from the sensors. Sustainability score of each building is evaluated by a sustainability score evaluation module (218) that compares KPIs of the assets against a selected compliance standard. A global sustainability score of the entity (102) is estimated by aggregating sustainability scores of each building and assessing weights assigned to the KPIs by an aggregation module (220). A reporting module (222) displays a report with global sustainability score of the entity (102) along with sustainability scores of each building.