An enquiry, review or investigation looks at the circumstances giving rise to an out of the ordinary event, including the actions of participants. An enquiry, review or investigation may result in suggestions for Code amendments, market facilitation measures, or in a finding that no further action is needed. In all of these cases the Authority usually publishes a report of its findings.

At the same time as it carries out a market performance inquiry, investigation or review, the Authority’s compliance team may investigate whether there has been a breach of the Code, Act or Regulations. The two processes may run concurrently, but may not be completed at the same time.

Enquiries, reviews and investigations represent three stages in an escalating process, with increased effort and significance attached to each one.

Stage I (market performance enquiry)

At the first stage, the Authority carries out low-cost ad hoc analysis using existing data and resources. The purpose of an enquiry is to better understand circumstances, observed through routine monitoring, that appear to require closer inspection. The Authority would not usually announce it is carrying out an enquiry.

If the results of the enquiry show that the circumstances are unlikely to have any implications for the Authority’s statutory objective competitive, reliable and efficient operation of the electricity industry, the Authority is unlikely to take further action. The Authority publishes the results of its enquiry only if the matter is likely to be of interest to industry participants.

Stage II (market performance review)

The Authority will initiate a review if, at the end of a Stage 1 enquiry, it does not have enough information to understand the issue but it appears to be significant for the competitive, reliable or efficient operation of the electricity industry. The Authority makes relatively informal requests for information 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 would not announce it is undertaking this work unless there was a high level of stakeholder or media interest.

Stage III (market performance investigation)

At this stage, the Authority may exercise statutory information-gathering powers under section 46 of the Electricity Industry Act to acquire the information it needs to investigate an issue in depth. The Authority would generally announce early in the process that it is undertaking an investigation and indicate when it expects to complete the work. The Authority generally publishes reports of Stage III investigations. 

Market events

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.

2013 enquiries, reviews and investigations 

  • Historical analysis of electricity costs
  • High North Island prices coinciding with HVDC test on 3 October 2013 
  • High spring washer price situation of 20 June 2013
  • Impact of incorrect metering situation for 28 April 2013
  • Impact of HVDC pole 3 commissioning on the wholesale electricity market
  • Enquiry into increased market prices from 27 February 2013
  • Enquiry into manual price publication for trading period 31 on 26 February 2013

2012 enquiries, reviews and investigations

  • 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

2011 enquiries, reviews and investigations

  • 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

2010 enquiries, reviews and investigations

  • Wholesale electricity prices: December 2010