Building energy management systems automate certain processes to maximise their efficiency, reducing electricity and heating demand.

Building energy management systems are also known by various other names such as building control systems, building automation systems, or smart building controls. These are designed to automate and optimise certain building processes, thus saving money on energy bills, manpower costs, and equipment maintenance.

Some examples of processes these systems control include heating, ventilation, cooling, chillers, solar shading, Lighting & Lighting Controls, electricity generation, import, export, storage, carbon dioxide (CO₂) intensity, and supply to different areas, lifts, CCTV, building access, public address systems, and alarms.

Building energy management systems vary widely in their capability, which systems they can be integrated into, complexity, capital and maintenance costs, and payback. Systems can be 'turnkey', requiring minimal setup, right the way through to bespoke systems made uniquely for one building. A key consideration is how much capability a building can benefit from. What current equipment would be most compatible with a control system? What process would be most cost-effective to automate?

A building energy management system will require electricity, internet, and equipment room space. For each aspect of the building that is to be controlled, the system will also need inputs, monitoring, and communication. The system could need either wired or wireless communication with any Smart Meters, Heating Controls, Lighting & Lighting Controls, and Battery Storage monitoring, as well as potentially supplementary sensors too.

As with any system, security is an important issue. Cybersecurity flaws have previously been found in building energy management systems, so it is important to take appropriate precautions around passwords, firewalls, and other cybersecurity measures.