This paper introduces HEMIS, a home energy management intelligent system based on a hybrid cognitive reactive multi-agent system. Thanks to smart metering, HEMIS provides real time and easy access to multiple physical properties including energy consumption, temperature, air quality This collected data is used by the system in order to activate predefined scenarios enabling home automation and energy saving. The system acts on the environment via actuators such as heater controllers, roller shutters on windows or doors, alarms The HEMIS consists of two layers: cognitive multiagent systems where concepts which are easily understood and used by the users, are represented by cognitive agents and a reactive layer closer to the physical world. Our system is accessible anywhere thanks to the HTML5 web application.