Simplified VO M&V ProtocolsApproved May 4th, 2010
1. Simplified VO M&V Protocol can be applied to distribution systems with Residential and Small Commercial Loads to verify energy savings from reduced voltage operation.
2. Protocol makes use of historical data, system modeling, 7-day M&V ‘on’ and 7-day ‘off’ hourly measurements, and “Deemed” end-use VO Factors determined from NEEA DEI Study 2007 results.
3. Protocol can be used with three Voltage Regulation Techniques, VFR, LDC, and AVFC.
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126Volts
120
114Feeder Length
Three Voltage Regulation Techniques1. Voltage Fixed Reduction (VFR)
• Fixes the voltage level at the substation source and the voltage level at the end of the feeder varies with load
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• Old voltage setting Vset = 125V, R and X settings = 0
• New voltage setting Vset = 122V, R and X settings = 0
Existing Vset = 125VNew Vset = 122V
126Volts
120
114Feeder Length
Three Voltage Regulation Techniques2. Line Drop Compensation (LDC)
– Fixes the voltage level at the end of the feeder and the voltage level varies at the substation source with load
3
• Old voltage setting Vset = 125V, R and X settings = 0
• New voltage setting Vset = 120V, R and X settings = 3 to 5
Existing Vset = 125V
New Vset = 120V, R and X setting = 3 to 5
Three Voltage Regulation Techniques3. Automatic Voltage Feedback Control (AVFC)
– Fixes the voltage level at the substation source based on real-time voltage feedback sign from the end of the feeder
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(s)
126Volts
120
114Feeder Length
Three Voltage Regulation Techniques3. Automatic Voltage Feedback Control (AVFC)
– Fixes the voltage level at the substation source based on real-time voltage feedback sign from the end of the feeder
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• Old voltage setting Vset = 125V, R and X settings = 0
• New voltage setting Vset = 119V, R and X settings = 0
Existing Vset = 125V
Vset = Adjusts for load conditions based on end of line feedback
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Voltage Control Zones
Load Tap Changer (LTC)
Transformer
Feeder Breaker
Feeder
VCZ for LTC
Secondary Voltage
Zone
Primary Voltage Zone
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Voltage Control Zones
Load Tap Changer (LTC)
Transformer
Feeder Breaker
Feeder
VCZ for V-RegVCZ for LTC
V-Reg
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Four Stages to Simplified VO M&V Protocol
Existing Performance Assessment and
VO Implementation Plan
System Improvements Baseline Pre-VO
measurements
VO Implementation Post-VO Measurements
and Verification
Persistence Measurements
Historical Load Data: kWh-annual, Volt_Drop-max, kWpeak-demandDistr _Line ModelingLoad_Flow AnalysisThreshold AnalysisDetermine end-use VO FactorEstimate Potential SavingsInstall VO and SI Improvements
1.
2.
3.
4.
7-day measurements ‘OFF’Veol, Vset, Esub Calculate Vpre-annual average
7-day measurements ‘ON’Veol, Vset, Esub Calculate Vpost-annual averageDetermine Verified Savings
Performance Thresholds• Power Factor
Power Factor on average > 98% (period)Power Factor minimum > 96% (period)
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• Phase UnbalanceMust be < 0.15pu, or < 40 amps
• Voltage Drop (Vd) for each voltage control zoneMust be < 3.3% on primary at feeder peak loads
Performance Thresholds (continued)
• Maximum Voltage Drop (Vd) for secondary
– Must be < 4.0%, based on design standards and criteria
• Voltage level must be > (114V+1/2 Bandwidth) and less than (126V-1/2 Bandwidth)
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• Maximum Voltage Drop Variance (Vdv) between feeders within the same voltage control zone (during period)Must be < 0.25 p.u. or < 2.0V
Why Performance Threshold are Critical
Establishing thresholds helps to resolve key issue found in the pilot NEEA projects that did not perform well.
• Reduces voltage fluctuation due to changing loads/conditions
• Reduces losses in the distribution system• Allows recording periods to be minimized (1 week to
establish daily load shapes and weekend/weekday load shapes)
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VO Factor Determination
• Uses Results from the NEEA DEI study to determine
– Heating and cooling zones
– Residential and commercial load
– End-use load characteristics• Electric heating
• Air conditioning
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395
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NEEA DEI Study VOf SensitivityMinor impacts due to AC End-Use Load
VOf with Heating Zone = 2 Cooling Zone = 2Each Curve Represents % of Homes with Airconditioning
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 10 20 30 40 50 60 70 80 90 100
% Non-Electric
VO
f R
es
ide
nta
l H
om
es
0
10
20
30
40
50
60
70
80
90
100
16% Variation
Voltage Reduction Calculation
• Calculate ΔV for each voltage control zone• Dependant on which voltage control method
– VFRAdjusted Average Voltage for VFR =
[Regulator_Set_Point_Voltage_Setting – ½ * A * Annual_Load_Factor]
– LDC/AVFCAdjusted Average Voltage for LDC =
[Regulator_Set_Point_Voltage_Setting + Annual_Load_Factor *[B - 1/2 *A]]
Where:A is the maximum voltage drop at peak load, and B is the Calculated Regulator Maximum Annual Volt-Rise
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Energy Saved = Change in voltage x Voltage Optimization Factor x Annual Energy +
Energy Saved from System Improvements
E Saved = ΔV x VOf x E Annual + ΔE SI
• ΔV - determined from this program
• VOf - derived from NEEA load research study and confirmed by EPRI studies, and other industry pilots and research
• E Annual – Metered Data from Utility• ΔE - Energy Saved from System Improvements
From NEEA’s DEI research and pilot
VO calculation method already “approved” by RTF
Method of Calculating Energy Savings (Delta V)
From proposed protocols