New Zealand Steel comments regarding the ... - Transpower

New Zealand Steel comments regarding the consultation paper Customer-Facing Grid PerformanceMeasures, dated October 2012.Questions1. What matters to customers (Section 2)Our preliminary views are that the following are important issues to consider inredeveloping our performance measures:The number and duration of outages are the most important factor forcustomers.Measures and targets should be meaningful to individual customers; systemaverages are of limited relevance to customers.Customer expectations vary.Customers' tolerance of an outage depends on the cause and how good we areat providing information.Overall performance matters; grid performance is only part of the servicedelivered to consumers.Do you agree with these? (yes/no)As a general statement, yes.From a business/operating efficiency perspective, there is no tolerance for outages,whatever the cause.What other matters are important to you as a Transpower customer, or do you think areimportant to consumers?Over the last 20 years, we have kept a list (non-exhaustive) which outlines most ofthe interruptions (both short and not so short) that we have experienced. Againsteach entry, we place a dollar figure as to how much each interruption is estimatedto have cost the company. We can provide this information to you and it shouldbe recorded by Transpower.Measure of reduced security ie reporting when the ‘lights stay on’, but the gridconfiguration (planned and unplanned) reduces security from say n-1 to n.2. Different target categories (Section 3.1)Do you think it a good idea to set different targets for different categories of customers atthe grid connection? (yes/no)YesDo you think our proposed categories make sense or do you have any other suggestions?No other suggestions at this stage.3: Number of power outages measure.Section 3.2Do you agree with the definition of the number of power outages measure including theproposed exclusions and the way we propose to set the targets? (yes/no)No

QuestionsDo you have any comments or suggestions?Over the last 20 or so years, we had had far more problems with “short term outages”than the longer ones. We experience these “short term outages” as voltage dips ormomentary interruptions and then a second or so later, the voltage is back to normal, butthe damage has been done. Most of these disturbances come via the Transpowernetwork from the local lines company network, but some of them have originated fromfaults on Transpower assets at the Otahuhu substation, Penrose substation and various HVlines in the Auckland Isthmus area.So we do not agree with Transpower’s contention that outages of less than one minutelong be excluded from the measure. More specifically, we would like all disturbances thathave originated from Transpower equipment be part of the overall measure.Do you think we should include or exclude outages caused by extreme conditions such asearthquake or snow storm?They should be included, but possibly with a rider explaining the severity of the causingevent.4: Duration of power outagesSection 3.3Do you agree with the definition of the duration of power outages measure including theproposed exclusions and the way we propose to set the targets? (yes/no)As per the above, we don’t agree with the non-measurement of sub one minute outages.Do you have any comments or suggestions?NoWhat are your views on how we should measure durations where customers backfeed orload manage during a transmission problem.The duration should be from when the customer losses supply to when the customer hasfull supply restored. ie no load management is required, but supply may be by back-feedor alternate configuration.5: Information provisionSection 3.4Do you think the information provision measures we propose will be useful? (yes/no)YesDo you have any comments or suggestions on the proposed measures and targets?Information on economic impact should be includedInclude measures on reduced security – planned and unplanned (see Q1).6: Transmission outages compared to distributionSection 3.5Do you think a measure to compare transmission and distribution performance is useful?(yes/no)Yes

QuestionsIf so, which of the two measures is the most important?For NZ Steel, the transmission performance is more important