The Road to Net Zero: Lighting
In our last post, we focused on glazing and the View Dynamic Glass system. Next up, lighting.
In the typical commercial building in the US, lighting accounts for about 20% of the total energy (fossil fuel and electric) usage. Lighting is very interactive with occupant activity, daylight, and building schedules which provides great opportunities to “right-size” the required light levels and make the system responsive to dynamic variables. “Right-sizing” is defining the required light levels by space type and designing the lighting layout to provide the required level, and nothing more.
In order to optimize energy savings, the original fluorescent and incandescent lighting systems were retrofitted or replaced with LED alternatives. Existing fluorescent T12 office fixtures were replaced with pendant or surface-mount LED fixtures and existing historic fixtures were retrofitted with LED lamps (before and after pictures below).
The daylighting in our building provides significant interior light levels during the day. To respond to the varying daylight levels, all employees have the ability to adjust the general lighting in their area and also have LED task lighting to meet specific needs. As an added bonus, all occupants have the ability to control both color temperature and dimming options through a smartphone app.
As seen in the graph below, our energy consumption falls below both our predicted use and the ASHRAE 90.1-2007 baseline. Lighting accounted for 8% of our modeled energy usage and 11% of our actual energy use. The higher percentage of actual lighting usage for our building is due to the significantly reduced HVAC and plug load usage….more on that in our next update.
Extrapolating our savings data to account for an entire year gives a savings total of 17,300 kWh savings. That’s enough energy to power two American homes for an entire year!
More to come on our Road to Net-Zero in future building updates.