Every private office has an occupancy sensor in our newly built out Thinkspace office.  Our goal is to reduce energy consumption by more than 30% for the space that we occupy.  We installed commercial light fixtures with higher performance ballast and lamps.  That alone should help us get to the 30% energy savings.  In addition to energy efficient commercial light fixtures, we installed occupancy sensors.
There have been a number of times when I have been driving by the building at night and have seen lights on.  Sometimes people accidently leave the lights on in private offices and sometimes the cleaning crew forgets to turn off the lights.  This happens in the evenings during the week day and even over weekends.  With the installation of the occupancy sensor, we can ensure that lights are turned off if people are not working inside the space.
According to the EPA, occupancy sensors can reduce a room’s electricity consumption up to 90%.  Based on a study, here’s the estimated energy savings based on room type:

The other item that we also installed was the VendingMiser on our vending machine.  The VendingMiser powers down the lights and compressor of the vending machine if there are no people around in our kitchen area.  It still keeps the items inside cool but it dramatically reduces the amount of energy consumed by an average of 46%.  This saves about $150 per vending machine on an annual basis as each vending machine consumes approximately 7-14 kWh per day.  It feels great to be reducing our energy consumption as well as creating a more energy efficient space.  These types of energy reducing methods also count toward our LEED certification.
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