One Buckhead Plaza, Atlanta, GA
EMCOR Services Aircond was selected by the client for their ability to complete projects on time—while keeping tenants in place in the building—and their knowledge and expertise in applying for energy rebates on behalf of its customers. Upon successful completion and submission of the energy rebate paperwork, Aircond obtained $49,000 in rebates for the client.
The client was in need of mechanical and building automation construction services for a 410,000-square-foot multi-tenanted commercial class A office building in Atlanta known as One Buckhead Plaza. All services needed to be completed while the building remained up and running and occupied with tenants.
The One Buckhead Plaza HVAC retrofit project included two major renovations: mechanical and automation. Both projects were integral in securing the $49,000 of energy rebates from GA Power. The project consisted of replacing a 600-ton chiller, a four-cell cooling tower, and various pumps. Along with the mechanical upgrades, the controls were updated and replaced from pneumatics to DDC.
The One Buckhead Plaza mechanical renovation involved the upgrade of several major mechanical components within the 1,600-ton central cooling plant. The total cooling for this 20-story building includes two 600-ton water-cooled chillers and one 400-ton tenant- water-sourced heat pump loop heat exchanger.
The mechanical renovation included replacement of the 1986 York Constant Speed Centrifugal 600-ton chiller with a Trane Variable Speed Centrifugal 600-ton chiller; replacement of a four-cell, four-fan 1,600-ton cooling tower; replacement of two constant speed 15-hp primary chilled water pumps and two constant speed 30-hp secondary chilled water pumps with two variable primary 50-hp chilled water pumps; and conversion of the primary-secondary chilled water piping to variable primary chilled water piping. We also put VFDs on four existing condenser water pumps, two existing 50-hp condenser water pumps serving the two 600-ton chillers, and two existing 40-hp condenser water pumps serving the 400-ton tenant water-sourced heat pump loop heat exchanger.
The One Buckhead Plaza automation renovation included full replacement and upgrade of the existing HVAC control system with a new SmartStruxure DDC control system; conversion of the pneumatic controllers for the 500 VAV and series and parallel fan- powered boxes to DDC controllers; replacement and upgrade of the pneumatic/electric controllers for the 22 VAV chilled water air handling units (AHUs) with DDC controllers; and replacement and upgrade of the pneumatic/electric controllers for the central cooling plant to DDC controllers. Additionally, the control system was programmed with HVAC control strategies, such as supply air temperature reset, air static pressure reset, water differential pressure reset, chilled water supply temperature reset, and condenser water supply reset to maximize energy savings.
Aircond was able to apply and qualify for two energy rebates on behalf of the client under the Georgia Power Commercial Energy Efficiency Program: the Custom Savings Measure Rebate and the VFD Measure Rebate. Qualification for the Custom Savings Rebate required detailed energy analysis of the One Buckhead Plaza building comparing two energy models (baseline versus proposed) to determine projected energy savings. The baseline and proposed models were required to follow the ASHRAE/ANSI 90.1-2007 Energy Standard for Commercial Buildings. The proposed model included energy modeling of the mechanical and automation upgrades and new automation strategies. The estimated projected savings in energy consumption and costs was determined to be 642,000 kWh and $51,400 per year. GA Power, through ICF International, reviewed and approved the energy modeling and analysis and awarded the client the $40,000 rebate maximum.
Qualification for the VFD Measure Rebate required that all variable frequency drives (VFDs) be installed on existing motors in existing HVAC systems. All motors were required to be 2- to 200-hp and have greater than or equal to 1,500 annual hours of operation. Additionally, the energy savings from the motors getting VFDs could not be included in any other energy rebate. The two 50-hp condenser water pumps and two 40-hp tenant loop condenser water pumps qualified for this measure, which paid $50/hp. GA Power awarded $9,000 for this measure.
One Buckhead Plaza, a 410,000 square foot commercial Class A office building, is positioned at the intersection of Peachtree Road and West Paces Ferry, and is considered one of Atlanta’s most prestigious business addresses. The building houses a conference center, a 9-level parking garage, and two of Buckhead’s top restaurants.