Value Delivered
For One Buckhead Plaza, EMCOR Services Aircond provided major renovation of HVAC and building automation systems.
Throughout this 410,000-square-foot multi-tenant Class A commercial space, we performed all services while the building remained open and occupied with tenants.
Our analysis estimated energy savings of 642,000-kilowatt hours and cost savings of $51,400 per year. Based on this analysis and use of variable frequency devices (VFD), we were able to complete and submit energy rebate paperwork that helped the client obtain $49,000 in rebates from Georgia Power.
Client Objectives
The client needed installation of complete mechanical and building automation solutions throughout a 20-story office building in Atlanta, Georgia while the building remained occupied.
Solutions
Our mechanical scope of work for this HVAC retrofit project involved replacement of an aging 600-ton chiller, four-cell cooling tower, and pumps with higher-efficiency units.
In addition to converting the primary-secondary chilled water piping to variable primary chilled water piping, we installed the following upgrades:
- Variable speed centrifugal 600-ton chiller
- Four-cell, four-fan 1,600-ton cooling tower
- Two variable primary 50-horsepower (hp) chilled water pumps
We also installed VFDs on:
- Four condenser water pumps
- Two 50-hp condenser water pumps serving the two 600-ton chillers
- Two 40-hp condenser water pumps serving the 400-ton tenant water-sourced heat pump loop heat exchanger
To renovate the building automation system, we converted pneumatic controllers and parallel fan-powered boxes to direct digital control systems. We replaced and upgraded the following to direct digital control systems:
- HVAC control system
- Pneumatic/electric controllers for 22 variable air volume chilled water air handling units
- Pneumatic/electric controllers for the central cooling plant
To help maximize energy savings, we programmed the control system with HVAC control strategies, such as:
- Air temperature reset
- Air static pressure reset
- Water differential pressure reset
- Chilled water supply temperature reset
- Condenser water supply reset
Additionally, we helped our client qualify for Custom Savings and VFD rebates through the Georgia Power Commercial Energy Efficiency Program.
To qualify for the Custom Savings rebate, we conducted a detailed energy analysis of the building, comparing baseline and proposed energy models for the mechanical and automation upgrades to determine projected savings.
Georgia Power, through ICF International, approved our energy modeling and analysis and awarded the maximum rebate amount of $40,000.
To qualify for the VFD Rebate, we installed VFDs on 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 VFDs could not be included in any other energy rebate.
The client’s two 50-hp condenser water pumps and two 40-hp tenant loop condenser water pumps qualified for this measure at $50/hp, earning a $9,000 rebate.
Client Background
One Buckhead Plaza is a 410,000-square-foot commercial Class A office building that houses a conference center, nine-level parking garage, and two premier restaurants.