Overview
Automatic Under-Frequency Load Shedding (AUFLS) exists to maintain the stability of New Zealand’s power system during severe under-frequency events. The scheme allows us to significantly reduce the likelihood of system collapse, avoid widespread blackouts, and ensure the power system can quickly recover. More specifically, this scheme means that we can automatically disconnect 32% of customers' load in the event of a loss of net injection that drops the system frequency to below 48 Hz.
We have prepared the following videos for you to learn more the AUFLS scheme:
- A playlist explaining the findings of AUFLS Scheme Design Report, including a video illustrating what AUFLS is
- Guidance videos showing how to use the AUFLS Data Portal.
Updates
North Island Connected Asset Owners (CAOs) are in the process of transitioning to a four-block AUFLS scheme. See the AUFLS Project web page for more information, or our AUFLS Transition FAQs document.
As specified in the Code, this will be in place by the end of June 2025.
Submitting AUFLS Profile Information
The Code requires North Island CAOs to provide their AUFLS profile data at least once every 12 months. Use our Operations Customer Portal to do this. You must submit this information by April 1st for the previous calendar year.
If you have not already registered for the Operations Customer Portal, you will need to register by following the instructions here, where you will also find some guiding documents to help you navigate the application and learn how to add other users.
Submitting Pre- and Post-event Data
Following an AUFLS event, all providers must submit pre- and post-event data to us within 30 days in the manner detailed in the AUFLS Technical Requirements Report. We have provided data templates to help you at the bottom of this webpage. If you wish to use a different format, consult the System Operator using this form.
Once filled out, submit your data to [email protected] for consideration.
Further Information
We have compiled the documents and templates below to support you following our process. Please review the appropriate section below to learn more about each topic, and if you have any questions, reach out to us at [email protected].
- Distribution Assets Testing
Document What’s it for? GL-EA-766 Companion Guide for Testing of Distribution Assets Outlines the general requirements of routine testing that apply to all asset tests prior to commissioning generation and for testing after any modification. DT-EA-1181 AUFLS Routine Testing Results Template Template capturing and consolidating an AUFLS provider’s testing data to perform a self-check or self-assessment before sending to the System Operator. Send to [email protected] once complete. DT-EA-1182 Statement of compliance - AUFLS Template for CAOs to confirm to the System Operator the 4 block AUFLS system is in compliance with the Electricity Industry Participation Code 2010. Send to [email protected] once filled out and signed by an accountable manager. - Data Templates for North Island Annual AUFLS Submissions
Document What’s it for? GL-EA-941 AUFLS Data Template Guide A guide to support you with providing data for the annual AUFLS data submission. DT-EA-942 GXP Load Profile Template Spreadsheet for Distributors to populate the average off-take load (MW) at each GXP for each trading period over the specified 12-month period. DT-EA-943 AUFLS Feeder Load Profile Template Spreadsheet for Distributors to populate the average load (MW) at each AUFLS feeder for each trading period over the specified 12-month period. DT-EA-944 Total Distributors Load Profile Template Spreadsheet for Distributors to populate the total load (MW) for each trading period over the specified 12-month period. DT-EA-945 AUFLS Feeder Configuration Template Spreadsheet for Distributors to populate the location, configuration and status of AUFLS feeders for the submission period.