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.

1

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

2

• 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

4

(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

5

• 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

6

Voltage Control Zones

Load Tap Changer (LTC)

Transformer

Feeder Breaker

Feeder

VCZ for LTC

Secondary Voltage

Zone

Primary Voltage Zone

7

Voltage Control Zones

Load Tap Changer (LTC)

Transformer

Feeder Breaker

Feeder

VCZ for V-RegVCZ for LTC

V-Reg

8

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)

9

• 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)

10

• 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)

11

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

12

395

13

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

14

15

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