DISTRIBUTION EFFICIENCY UPDATE

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Distribution Efficiency – Quick Review

• Tier 1 study (19 circuits) completed in 2011– Four circuits identified for pilot (Mill Creek, Clinton substations)– Seven circuits had at least one unstudied adjacent circuit

• Identified influential circuit parameters for CVR• Simplified Measurement & Verification Protocol for pilot• 2012 savings target: 0 – 0.111 aMW (972 MWh) from pilot• Planned Tier 2 study, circuit prioritization

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PacifiCorp’s 2012 Activities

• Engaged in industry research– DSTAR (www.dstar.org) Project P13-7 (still in progress)

• Distribution Systems Testing Application and Research

– NEETRAC (www.neetrac.gatech.edu) Project 11-136 (still in progress)• National Electric Energy Testing Research and Applications Center

• Engaged in Regional Technical Forum (RTF)

– Automated CVR Subcommittee & protocol development

• Review of applicable PacifiCorp standards• Clinton and Mill Creek pilot projects• Tier 2 study in Washington

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DSTAR Findings1. Demand :: Voltage relationship varies w/ feeder, time of

day, season, and over the long term2. Estimating circuit CVR factors from lab values (bottom

up) cannot work (too little information)

3. Accurate long-term day on/ day off is extremely difficult4. Increased frequency & severity of voltage sags5. Software estimates may not suffice for M&V

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NEETRAC Findings1. Statistical analysis performed on pilot by Palmetto

Electric Cooperative (SE South Carolina)

– Could not apply RTF’s Automated CVR Protocol #1 due to limited data

– 13 interested utilities participating in project

2. Demand :: Voltage varies w/ temperature, humidity, demand on previous day, and demand on same day of previous week

3. Must be analyzed on circuit by circuit and day by day basis

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RTF Progress• Currently two custom CVR protocols exist

– Simplified VO M&V Protocol (Approved 5/2010)

– Automated CVR Protocol #1 (Approved 4/2004)

• Both are under review for compliance w/ new (6/1/2011) RTF guidelines*, including:– A maximum error introduced by sampling– Sources stated for all assumptions– Results are reliable and sufficient to meet the needs of planners

and “support regulatory processes related to the adoption and planning of energy efficiency initiatives.”

*Guidelines are available at http://www.nwcouncil.org/Energy/RTF/Measures/Support/

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Questioning Protocol Assumption #1• Loads do not have to be distributed evenly?

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Questioning Protocol Assumption #2• End-of-line voltage varies linearly with load?

– Example from “Robustness of Simplified VO M&V Protocol Measurement Period of 7 Days” by Utility Planning Solutions, PLLC

– If end of line voltage can be estimated by load, then several calculations can be “simplified”

– The chart shown was derived from software, not actual reads

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Questioning Protocol Assumption #2• Actual pilot measurements show low linear correlation

15-minute averages shown

Large (~ 2v) bandwidth for any given load

No model predicts this accurately

Pilot Circuit

R2

Value

5Y608 0.02

5Y610 0.00

5W116 0.09

5W127 0.01

9Substation MVA

End

of L

ine

C p

hase

vol

tage

Measurement & Verification Considerations

• Physics of individual appliance (lab test) well understood• Physics of aggregate system not understood

– Variables exist on every level, and they change over time

• Substantial assumptions have to be made for M&V– Pre- and post-reduction average voltage must be estimated for all

customer locations, all year long– Energy response to voltage reduction must be estimated for all

customers, all year long (VO or CVR factor)– To date, no way to determine accuracy of estimates over time

• Who can find a consistent, accurate, low cost method to determine energy savings from voltage reduction?

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Review of PacifiCorp Engineering Handbook

• 1C.2.1 Voltage Level and Range June 2004

– High level look at ANSI service & utilization voltages• 1C.2.2 Steady State Voltage Level Nov. 1998

– Settings methodology (§ 4.1.3 and § A4) is CVR• 1C.3.1 Voltage Balance Nov. 1996

– Cites 3% maximum voltage unbalance as target– Accounts for economics, lowest total cost to customer and utility

• 1E.3.1 Distribution System Planning Study Guide Feb. 2000; minor updates Feb. 2012

– Discusses current unbalance, voltage unbalance, LDC settings, and capacitor location & settings in § 7.4, 7.8 and 7.11, and economics in § 8.3

• Overall a good balance of economics and efficient system design• Simplified Protocol states that standards become “entrenched” after three

years

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Clinton/ Mill Creek Pilot• Using two 7-day test periods for M&V yields energy savings of

±0.54 aMW, before improvements were initiated.• Example from 5Y610 (VO factor 0.446):

Week of 6/25: average voltage = 122.8 Week of 9/10: average voltage = 121.2

• How do we handle data issues?– One missing value affects all calculations– What if one of nine protocol thresholds is not met for a period of

time? Is the circuit non-compliant?

• At what point is the ‘cost-effective, reliable, feasible’ criterion of RCW 19.285 not met?

VO energy change by Simplified Protocol:

0.14 aMW(Biennial target = 0.111 aMW)

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2012 Tier 2 Study

• Completed by SAIC, included 25 circuits• Confirmed Tier 1 VO factor was too high (~30%)

• Reaffirmed Tier 1 finding that existing practices are very good

• Company’s avoided cost updated to $86.74/MWh• Nine additional viable circuits identified• Other circuits failed to comply with ESUE* thresholds, or

had too low a benefit/cost ratio (BCR)

*ESUE = Energy Smart Utility Efficiency, a Bonneville Power Administration program that includes system operational metrics for efficiency, is used in the Simplified Protocol.

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Anticipated Tier 2 Projects• Six circuits from Orchard Substation (Yakima, WA)

– Average cost $30k per circuit– 22 phase balancing locations– One line regulator bank– Lower substation base voltages from 121 to 120 & 119– BCR = 1.15, saving estimated 0.10 aMW

• Three circuits from Sunnyside Substation (Sunnyside, WA)

– Average cost $68k per circuit– 4 phase balancing locations– One line regulator bank– Lower substation base voltage from 121 to 119– BCR = 1.48, saving estimated 0.08 aMW

• M&V alternatives are being discussed14

Washington DE Plan

• 2013– Stay engaged with the industry

• RTF hopes to have new protocol usable by 2013 Q3

– Continue biennial pilot with Orchard T-3797 and T-5035• Consider M&V by software

– No further detailed circuit studies

• 2014– Implement Sunnyside T-3570

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Extra Slide

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