Enquiries, reviews and investigations
Stage I (Market performance enquiry)
Routine monitoring results in the identification of circumstances that require follow-up. This stage may entail the design of low-cost ad hoc analysis, using existing data and resources, to better characterise and understand what has been observed.
The Authority would not usually announce it is carrying out this work. This stage may result in no further action being taken if the enquiry is unlikely to have any implications for the competitive, reliable and efficient operation of the electricity industry. In this case, the Authority publishes its enquiry only if the matter is likely to be of interest to industry participants.
Stage II (Market performance review)
A second stage of investigation occurs if there is insufficient information available to understand the issue and it could be significant for the competitive, reliable or efficient operation of the electricity industry. Relatively informal requests for information are made to relevant service providers and industry participants. There is typically a period of iterative information gathering and analysis.
The Authority would usually publish the results of these reviews but wouldn't announce it is doing this work unless a high level of consumer or participant interest was evident.
Stage III (Market performance investigation)
Finally, under a full investigation, the Authority may exercise statutory information-gathering powers under section 46 of the Act to acquire the information it needs to fully investigate an issue. The Authority would generally announce early in the process that it is undertaking the investigation and indicate when it expects to complete the work. Draft reports go to the Authority's Board for publication approval.
Listed below are market events that the Authority is either currently considering or has considered through its three step process outlined above. Events are listed in chronological order.
- Enquiry into increased market prices from 27 February 2013
- Enquiry into manual price publication for trading period 31 on 26 February 2013
- Increased South Island reserve offer prices May 2012
- Reduced energy offers at Arapuni on 13, 14 and 16 April 2012
- Locally net pivotal generation
- Analysis of Transpower reports relating to 13 December 2011 event
- Frequency keeping costs for trading period 31 on 13 December 2011
- Impact of reduced HVDC south constraint on South Island reserves
- Impact assessment of Arapuni split
- Review of events of 13 and 14 December 2011
- Review of 26 September 2011 infeasibility situation
- Review of August 2011 frequency keeping costs
- Review of price separation during HVDC reversal
- Analysis of historical offer revisions
- Review of high spring washer resolution issue with SFT
- Review of Stratford peaker commissioning 8 February 2011
- Dispatch of unscheduled generation: 23-27 January 2011
- Wholesale electricity prices: December 2010