May 9, 2011 - Energy Efficiency
The Bank of America Plaza anchors a city block at the north end of downtown Columbia, S.C. Since taking ownership of the building in 2006, Cooper Realty Investments has been increasing its energy efficiency and performance with the help of Johnson Controls Inc. and the building’s property-management company.
The plaza is a 17-story complex containing more than 300,000 square feet of commercial office space. The management team capitalized on its energy-efficiency and performance improvements by earning certification under the U.S. Green Building Council’s Leadership in Energy and Environmental Design for Existing Buildings (LEED-EB) rating system.
The plaza was the first facility in the state to achieve LEED Gold certification for existing buildings.
Johnson Controls has been servicing building controls at the plaza since it opened in 1989. After taking ownership in May 2006, Cooper challenged Johnson Controls to provide a solution for improving the building’s performance and energy efficiency, as well as help the organization achieve long-term savings.
Within six months, Johnson Controls initiated a retrocommissioning study to identify potential energy-conservation measures. Over the next 18 months, Johnson Controls implemented a range of approved energy-conservation measures that resulted in an annual utility-cost savings of more than $43,000.
Measures included: upgrading variable-air-volume controls from pneumatic to digital; installing variable-speed drives on all cooling equipment; completing lighting-control retrofits; and upgrading controls to a Johnson Controls Metasys building-management system.
The Metasys system communicates using standard web browsers and maximizes monitoring and control of the building’s mechanical and electrical systems. Johnson Controls completed control-sequencing enhancements on equipment throughout the building. New controls on water heaters and unit heaters allow for off-hour scheduling and control sequencing to reduce energy use. Power-monitoring initiatives include sub-metering of individual floors and specific equipment.
“In the past, our building’s HVAC and lights basically ran 24/7,” says property manager Amy Marthers. “We are now able to better program equipment based on when the building is actually in use. And we’re able to give tenants some control of their own space during off-hours, which they like.”
A keypad on each floor allows tenants to override preset schedules for HVAC and lighting systems. Because the facility can track and report those billable hours, Marthers can better manage energy costs and justify tenant charge-backs when appropriate.
Johnson Controls used Energy Star’s Portfolio Manager energy-management tool to benchmark building performance at the beginning and end of the retrocommissioning process.
During retrocommissioning, Johnson Controls also trained in-house technicians on the proper ways to update the Energy Star data and more effectively use the Metasys system.
Says Marthers, “From where I sit, Johnson Controls’ professionalism and willingness to clearly explain things helps us work efficiently, without a lot of back and forth on a day-to-day basis.”
