Invest in facilities management tools.
“Ask your facilities manager to implement controls on your HVAC system to manage how much energy is used to heat your building, ranging from a wall-mounted thermostat to a computerized Energy Management System (EMS). An EMS uses sensors to adjust heating and cooling when a room is unoccupied, saving you energy and money.”
https://www.nationalgridus.com/Long-Island-NY-Business/Energy-Saving-Tips/Heating-Cooling