Turn out lights when not needed
Why
A Saskatoon school saved 43% of their lighting energy by turning off unnecessary lights. This would result in GHG emission reduction of 42 Tonnes CO2/year. In the attached graph, January and February are before the behaviour change, March is when unnecessary lights are off.
How
Start by encouraging people to turn lights off when they leave the room.
Can you rearrange workspaces to make better use of natural light? Would a small task light make some workspaces more comfortable than using the overhead lights?
Use signage at light switches, notes in newsletters, reminders at staff meetings, etc. to ensure everyone knows which lights are to be left on and which should be turned off.