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10% Worst Performing CircuitsReliability Program

SWEDE ConferenceSan Antonio, TX

May 10, 2007

Kenton M. Brannan, P.E.kenton.brannan@centerpointenergy.com

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10% Circuit Reliability Program

• Historical Approach

• Enhanced Process– Identification of Probable 10% Circuits– Circuit Evaluation & Improvements– Reliability Oversight Committee– Documentation Procedure

• Tree Trim Process

• Notable Changes

• Process Assessment

• Anticipated Process Enhancements

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Historical Approach

• 10% Circuit Standard– Performance measured from Jan 1 to Dec 31

– Prefer to have improvements made by Jan 1

• CNP’s Historical Approach– Circuit reviews began in 4th Quarter

– Infrared and Tree Trim processes separate from 10% circuit review

– No specific deadlines to complete action plans

– Differing methods among service centers

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Enhanced Process

• Identification of Probable 10% Circuits– Begins upon conclusion of 2nd Quarter with June

YTD circuit performance data

– Data available for analysis by mid-July

– Begin with top 30 circuits from SAIDI/SAIFI lists

– Confidence level: ≈ 25% of top 10 % circuits

– ≈ 15 circuits are added each month until year end

– Final 10% circuits (≈ 40) are identified by mid-January from year end data

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Enhanced Process

• Circuit Evaluation & Improvements – 90 Days– 90 day timeframe begins on date of identification

as probable 10% circuit

– 1st 45 days

• Perform root cause analysis and develop action plan to improve circuit performance

• Attempt to achieve “Reduce-To” values

– 2nd 45 days

• Complete field work called for in action plan

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Enhanced Process

• Reliability Oversight Committee– Consists of engineering and operations personnel

– Evaluates proposed action plans (within 1st 45 days)

• Documentation Procedure– Progress tracked via MS SharePoint

– Reports• Circuit Level Summary Report• System Reliability Dashboards

Circuit Level Summary Report

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Tree Trim Process

• Focus – 10% Circuits – 4th quarter of the previous year and

1st quarter of the new year– All Circuits – 2nd and 3rd quarters

• 4th quarter Selection Criteria– Information on probable 10% circuits– Outage data due to vegetation & wind– time since last trim– Emphasis on 10% circuits with highest priority

given to repeat and 300% circuits

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Timeline

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Notable Changes

• Timeframe– Begin closely analyzing probable 10% circuits in July

rather than October or November

• Infrared Process– Increase current inspection cycle from 3 years to 5– 5 year system focus (≈ 300 circuits/year)– Additional focus on 10% circuits (≈ 200 circuits)

• Tree Trim– New process has been enhanced to incorporate the 10%

circuits in the proactive tree trimming strategy

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Process Assessment

• Root cause analysis & circuit work is being completed earlier in the year as compared to past years

• Reliability Oversight Committee– Identifying synergies

– Sharing of resources occurring

• Process very effective thus far

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Anticipated Process Enhancements

• Identify probable 300% circuits before 2nd Q ends

• Refine target SAIDI and SAIFI values using historical values and statistical methods

• Abandon MS SharePoint and move to SAP/Business Warehouse