Energy Savings by

1
Energy Savings by Balancing Plant Air
Faiz Yono May 2008
2
Balancing Plant Air

• Background
• A transmission manufacturing facility
• Plant began production in 1956
• There have been 12 plant expansions
• Current plant area 3.1 million square feet

3
Balancing Plant Air

• Air Balance Analysis
• Goal was to reduce heating costs
• Retained services of a consultant (Benham
  Engineering)
• Field survey heating and ventilation system
• Walkthrough of all inlets / outlets
• Measurement of key ventilation parameters
• Review of air quality data

4
Balancing Plant Air

• Plant Air Flow Balance
• Air Supply
• Air Handlers
• Roof Blowers

Air Handlers
5
Balancing Plant Air

• Plant Exhaust
• Building Exhaust Fans
• Oil Mist Collectors (Process Exhaust)
• Production Washers (Process Exhaust)
• Heat treat Furnaces (Process Exhaust)

Roof Exhaust
Oil Mist Collectors
6
Balancing Plant Air
Production Washers
Heat Treat Exhaust Fans
7
Balancing Plant Air

• Scope of Problem
• Process exhaust air has been added over the
  years to improve air quality
• Oil mist collectors account for 1.5 million
  CFM compared to a total of 2.2 million CFM
• 68 increase in exhaust with no additional
  increase in supply or reduction in other exhausts
• Plant had negative pressure
• Any changes cannot adversely affect air
  quality and should help improve it

8
Balancing Plant Air
Effects of Negative Pressure

• Flexible roll-up doors pushed inward
• Plant perimeter cold in the winter months
• Infiltration as high as 1,250 ft per minute
  (equivalent to a 14 mph wind)

9
Balancing Plant Air
Air Balance Study Recommendation

• Four Operational Modes
• 1. Shutdown Mode (long holidays)
• Shut off roughly 80 of all ventilation
  equipment
• 2. Winter Operation
• Shut down the majority of building roof
  exhausters
• 3. Spring / Fall Operation
• Maximize operation of roof exhausters
• 4. Summer Operation
• Similar to Winter Operational Mode

10
Balancing Plant Air
Implementation Holiday Shutdown

• Operate one third of the units used during
  normal operations
• Turn off ALL building roof exhaust fans
• Shut down oil mist collectors
• Reduce by 10 degrees the temperature set-points

• Results
• Positive plant air pressure
• More uniform facility temperature
• Take advantage of large thermal mass

11
Balancing Plant Air
12
Balancing Plant Air
Implementation Winter and Summer Operation

• Turn off building roof exhaust fans and close
  dampers
• Increase outside supply air by zone
• Reduce air supply units set points

• Results
• Reduced Infiltration
• Positive air pressure
• More uniform facility temperature
• Improved air quality

13
Balancing Plant Air
14
Balancing Plant Air
15
Balancing Plant Air
16
Balancing Plant Air

• Conclusion
• 30 Reduction in Natural Gas Usage
• 10 Reduction in Electricity Usage
• Improved Air Quality
• More Uniform Temperatures Throughout the
  Facility