Main Library Energy Retrofit
Innovation SummaryThe Main Library is over 700,000 square feet of space built in three stages beginning in 1955. The HVAC units were also added in phases and are inefficient and costly. Working with Duke Energy through their SmartBuilding Advantage program changes are being implemented that improve efficiency and reduce costs 37%.
Problem StatementOur Main Library is a sizable building designed and constructed in three stages. The first portion relocated the former Main Library collection in 1955. An addition was constructed in 1982 and a second addition was constructed in 1995. When the 1995 addition was constructed, the then administration decided not to run a gas line to the new addition requiring heat and hot water to be piped across the street to the addition. This decision coupled with the age of the HVAC units in the earlier buildings and the mix of heating and cooling equipment and controls used made heating and cooling the Main Library very expensive. With utilities costs rising, operating budgets shrinking and a desire to be a greener organization, it was time to look at changes to the Main Library.
Through Library Trustee Bill Moran we learned of a program offered by Duke Energy called SmartBuilding Advantage. This program promotes and implements commercial and institutional building efficiency improvement, an element of Duke Energy’s ongoing commitment to energy efficiency and customer service. Over a period of about one year, Duke and engineering firm Building Intelligence worked with our staff to make recommendations of changes to our facility that would reduce operating costs, save energy and make our building more comfortable year round. The cost of the engineering study was paid for by Duke. The proposed revisions recommended for the Library span a spectrum of mechanical, lighting and controls improvements. Major elements include: • Lighting upgrade: Retrofit remaining T-12 florescent lighting to T-8. • Lighting controls: Apply daylighting at perimeter zones, and occupancy control in offices, conference rooms, and restrooms. Lighting energy savings can be further augmented by applying automatic lighting timers in the stacks. • Re-commissioning: Re-commissioning of HVAC systems including the boiler and chiller plants. • Major mechanical retrofits: For the aging mechanical systems in the 1952 and 1982 buildings, a phased program of equipment replacement is recommended. • Building automation and control system upgrades: Upgrade of building automation and controls to a web based system. • Alternate summer re-heat: In order to eliminate operation of the main boiler plant during the cooling season. The proposed revisions are estimated to yield annual energy savings of over $430,000 per year, a 37% improvement overall, at an estimated cost of approximately $2.64 million before factoring in incentives provided by Duke. Incorporating estimated incentives reduces the cost to $2.26 million.