This document has established a new harvesting energy technology for sustainable energy in smart building. However, smart buildings are considered by the combination of several technologies, sensors, and devices designed to capture and analyze data. In addition, building data is used to improve the operational efficiency of buildings, particularly in the management and optimization of resources and services. Additionally, this approach brings together data from a variety of sources, including people, equipment, infrastructure, and systems. Furthermore, these integrated systems contribute to the sustainability of buildings by optimizing energy consumption and minimizing waste. Additionally, the energy harvested can be used to power sensors, appliances, and other infrastructure components, enhancing building intelligence and efficiency. Beyond improving energy efficiency, this approach ensures that energy collectors in public buildings are managed in line with sustainable development objectives, reducing dependence on conventional energy sources. Finally, digital simulation confirms the monitoring and control of essential systems such as energy, lighting, heating, aeration and air conditioning (HVAC). In the same way, the consumption of this public building has been reduced, and its dependence on conventional energy sources is minimized.