In response to several questions and comments about impact of the new exterior lighting at Hunt Library on CMU energy consumption, an engineer for the project writes:
“The Hunt Library exterior lighting project sought to create an aesthetically pleasing effect on the exterior of the building, while maintaining an energy-efficient and sustainable design. The façade lighting utilizes 50-watt, long-life LED fixtures. By installing high output, energy-efficient fixtures, the design passed the state energy codes for façade lighting by 58%. Although the design only consumes 40% of the energy permitted for façade lighting, the project scope also included the replacement of several site fixtures to offset the increased wattage from these light fixtures. The existing security lighting for the sidewalks adjacent to the Library was previously provided by three 1000-watt flood lights and six 210-watt pole mounted lantern-style fixtures. These fixtures were replaced by six 71-watt LED site fixtures, which are energy-efficient, long-life, and dark-sky compliant. This replacement resulted in a net decrease of about 3800 watts. Overall, the only wattage increase for the addition of façade lighting on Hunt Library, as well as three site fixtures for security lighting along the sidewalk adjacent to the peace garden, was about 800 watts – which is approximately equal to the energy consumption of a coffee maker.”
Amy L. Ford, P.E.
LEED AP BD+C