Chris Miller, PE, CxA

1
Sub-Metering Meter Basics And Integration

• Chris Miller, PE, CxA
• P2S Engineering, Inc.
• Chris.Miller_at_p2seng.com

2
Presentation Outline

• Why Sub-Meter?
• What to look for in a Meter?
• Integration into a Control System
• What Can Be Done With the Data?

3
Why Sub-Meter

• Identify where utility money is going (and where
  is shouldnt)
• Baseline Performance and of Post Energy
  Conservation Measures (ECMs)
• Performance Based Maintenance
• Right Sizing of Future Equipment
• Equipment and Integration is cheap

4
Proper Sizing of Equipment
5
What to look for in a Meter

• Liquid Flow Meters
• Chilled Water, Heating Hot Water
• Domestic Cold and Hot Water
• Actual Flow Range
• Temperature Ranges
• Rate of Change
• Ultrasonic
• Magnetic
• Orifice
• Paddle/Turbine

6
What to look for in a Meter

• Gas Flow Meter
• Natural Gas
• Air Flow
• Steam
• Actual Flow Range
• Pressure Ranges
• Thermal Mass Flow
• Vortex
• Magnetic
• Orifice
• Turbine / Rotary Device

7
What to look for in a Meter

• Electric Meters
• True RMS
• Know Actual Range
• Use a Communication Meter
• Modbus / Lon / BACnet Etc.
• No on Analog 4 -20 ma
• Temperature Sensors
• Matched Pair RTDs
• Maintain Meters and Sensors Calibrate Annually at
  Least

8
Integration into a Control System

• Demand Control
• Reset Zone Set Points
• Reset Fan Speeds to 50
• Turn Off Lights or Dim
• Maintain Meters and Sensors Calibrate Annually at
  Least

9
What Can Be Done With the Data?

• Easily Identify Energy Waste
• Simultaneous Heating and Cooling
• With Energy Use Index (EUI)
• Compare energy use of buildings overall
• Compare energy use of subsystems
• Lights, Fans, Pumps etc (kW/sqft.)
• Chiller systems kW/Ton
• Identify Performance Based Maintenance

10
Proper Sizing of Equipment
11
Chilled Water Plant Efficiency

• Operating kW/ton achievable in todays plants
  (includes chillers, cooling towers and pumps)
• 0.5 - 0.7 Excellent
• 0.7 - 0.85 Good
• gt1.0 Needs Improvement
• Do you really know how your chilled water plants
  are performing?

12
Control Systems and Techniques
12
13
Summary

• Knowing where the energy is going is important
• Helps on making economic decisions
• Critical in high performance facilities
• Relative cost is cheap. Not having the
  information is not.

14
Albert Einstein
Everything should be as simple as possible, but
no simpler
Insanity doing the same thing over and over and
expecting different results
14