Improving%20Quality%20of%20Service%20

1
Improving Quality of Service Information and
Incentives in the GB Electricity Industry

• Alan Friday (ERA Technology Ltd), Chris Watts
  (Ofgem)

2
Contents

• Overview of IIP
• Audit framework
• Statistical work
• Overall impressions
• Results of the audit

3
Overview of IIP

• Address known weaknesses of RPI-X regulation for
  the DNOs
• Improve quality of service data
• Improve balance between incentives for cost
  efficiency and quality of service
• Key quality of service measures identified as
  being
• Frequency and duration of supply interruptions
• Speed and quality of telephone response

4
Overview of IIP (2)

• Over past 2 years Ofgem and the industry have
  been working to ensure that quality of supply
  information is
• accurate
• as consistent as possible across companies
• To achieve these goals Ofgem has put in place
• standard definitions and guidance
• minimum levels of accuracy for reporting
  interruptions
• annual audits of data

5
Overview of IIP (3)

• New quality of service incentive scheme in place
  on DNOs from 1 April 2002 to 31 March 2005
• Up to 2 revenue at risk (4 million)
• Rewards and penalties for performance against own
  targets for number and duration of interruptions
• Relative scheme for quality of telephone response

6
Audit framework
7
Statistical analysis-nature of interruption data

• Data is highly skewed
• Mean 191
• Median 12
• ? 817
• Usual method using sampling charts based on
  normal distribution not applicable

8
Statistical analysis-describing the data

• Data fitting software used to investigate which
  distribution best describes the data
• Lognormal provided the best fit
• Characterised by 50 value (M) and slope (S)
• Iterative process used to define sample size

9
Audit process

• Data from each DNO analysed to determine sample
  sizes for low voltage and higher voltage
  interruptions
• Specific incidents selected and communicated to
  each DNO to allow preparation
• Each incident scrutinised by audit team to
  determine appropriate CIs and CMLs
• Audited and reported values recorded in incident
  work book
• Workbook for each DNO used to determine accuracy
  of measurement system

10
Results of the audit

• Main sources of inaccuracy were
• inaccurate reporting of customer numbers before
  new connectivity systems were introduced
• manual intervention in incident reporting
• inaccurate reporting of customer numbers for LV
  faults affecting only part of a feeder
• missing restoration stages
• incorrect incident start times

11
Overall impressions

• Impressive amount of work has been done by all
  DNOs in developing their systems to meet accuracy
  targets
• Welcome the commitment that DNOs have made to the
  audit process
• preparation of audit trail
• availability of appropriate staff
• Culture change in many DNOs emphasising
  importance of correct information