NZX is contracted as the WITS manager.

NZX website

The purpose of the WITS is to act as a central facility for the receipt and publication of information between and on behalf of the various parties involved in the wholesale electricity market.

Purchasers and generators send their bids and offers for energy and reserves to WITS, which validates them and sends them to the system operator for use in their scheduling and dispatch process. When the resulting prices and quantities have been calculated, the system operator sends these to WITS for publication to generators and purchasers.

The pricing manager sends provisional and final prices to WITS for publication to the market.

The clearing manager sends constrained on/off amounts and block settlement differences to WITS for publication to the market. It also sends invoices to WITS for distribution to participants.

WITS itself compiles compliance information and sends it to the Electricity Authority. It also keeps track of bids and offers throughout the day so that it can publish real-time information and the final bids and offers to the public domain.

Publication involves the downloading of data files and presentation of selected data in graphical format.

WITS is a 24x7 system because bids and offers can be submitted round the clock and information is published at least every 5 minutes. Bids and offers can be revised up to the start of the next trading period (half hour). Bids and offers form part of the supply and demand data required by the system operator to forecast the scheduling of generation and reserves. Schedules are published every half hour. Some participants have developed automated systems to submit and receive information from WITS automatically. As a result, because disruption to the WITS system causes difficulties to all parties involved in the day-to-day running of the electricity market, 13 of the Code requires that backup arrangements are put in place to ensure that alternative submission and publication mechanisms are available.

The latest functional specification and operational requirements are available below. The backup arrangements are available on the the WITS and order submission user backup procedures page. 


  • WITS and order submission user backup procedures

    Published: 18/09/2013 12:00am

    The user backup procedures and contingencies in place for WITS’ interfaces with clients, with specific emphasis upon the order submission process. Read More

  • WITS monthly reports

    Published: 14/01/2013 12:00am

    Service providers are required to provide monthly performance reports to the Authority. The WITS Manager, Pricing Manager and Clearing Manager reports are provided together. These can be found below. Read More