The reduction in energy consumption can be astounding if you commit to making some small behavioral adjustments within your organization.
Shut blinds at night (and, in hot weather, during the day) to help insulate. Open blinds in cold weather to help passively heat the space.
Shut computers down at night & over the weekend. Plug monitors into power strips and turn off at night & over the weekend. Switch PCs to “energy efficient” modes. Read more about computer energy efficiency here.
Plug computer monitors and other electronic equipment that doesn’t need to stay on over the weekend and overnight (i.e. not fax machine or server) into a power strip, and turn power strip off during off hours. This will help prevent these “energy vampires” from continuing to draw a charge even when not in use.