TPM Operational Review - Workstream 1

Workstream 1 focussed on practical changes and ‘quick wins’ that can be implemented ahead of the next pricing year (starting 1 April 2027).  Key elements of the Workstream 1 proposal include:

• Batching adjustment events to significantly reduce inefficient price volatility
• Removing substantial sustained increase (SSI) adjustment events, which have been impractical to apply in practice
• Deferring simple method benefit-based charge (BBC) recalculation to allow completion of the next phase of the TPM Operational Review
• Simplifying and tidying up TPM drafting 

Our Workstream 1 proposal documents can be found below:

• Workstream 1 proposal to the Electricity Authority
• Appendix A - Code Amendment Request - Adjustment Events Batching April 2026
• Attachment A.3 - How batching would change the timing of charges and wash-ups for the causing customer and other affected parties
• Appendix B - Code Amendment Request - Removal of SSI Adjustment Events April 2026
• Appendix C - Code Amendment Request - Simple Method Period Extension April 2026
• Attachment C.1 - Analysis of power flows in simple method regions
• Appendix D - Code Amendment Request - Legal Drafting Tidy-Ups April 2026
• Appendix E - Proposed drafting changes - Adjustment Events Batching
• Appendix F - Proposed drafting changes - Removal of SSI Adjustment Events
• Appendix G - Proposed drafting changes - Simple Method Period Extension
• Appendix H - Proposed drafting changes - Legal Drafting Tidy-Ups

Consultation and submissions

This consultation is now closed. Thank you to everyone who submitted feedback.

In March 2026 we sought feedback on the first tranche of potential changes we were considering as part of Workstream 1 of the TPM Operational Review.

The consultation period ran from Tuesday 3 March 2026, until Friday 20 March 2026.  

There was no cross-submission stage due to the technical nature of the Workstream 1 amendments, as well as the timing constraints for the changes to be implemented for the next pricing year (1 April 2027 – 31 March 2028).  

The consultation documents are below:

• Consultation paper on TPM Operational Review Workstream 1
• Appendix A - TPM guidelines
• Appendix B - Cost-benefit analysis for adjustment event proposal
• Appendix C - Proposed TPM drafting for housekeeping changes
• Appendix D - Questions from the consultation on TPM Operational Review
• Appendix E - Proposed TPM drafting for housekeeping changes with track changes

Submissions

We received 13 submissions in total. Thank you to everyone who contributed their feedback. 

A summary of submissions is provided below:

• Summary of submissions

Click below to read each submission:

• Contact Energy
• Electricity Networks Aotearoa (ENA)
• EA Networks
• Fonterra
• Genesis Energy
• Independent Electricity Generators Association (IEGA)
• Lodestone Energy
• Meridian Energy
• MEUG
• Orion
• Unison and Centralines
• Vector
• Westpower

Industry Working Group (IWG) documents

The following papers include materials produced by Transpower for the Industry Working Group (IWG) and final advice from the IWG. They reflect our evolving thinking on the issues and should not be taken as Transpower’s final or formal views on the issues presented.

• Meeting one - agenda and briefing paper
• Meeting one - feedback to Transpower
• Meeting two - briefing paper
• Meeting two - feedback to Transpower
• Meeting three - briefing paper
• Meeting three - feedback to Transpower
• Adjustment event workflows

Online presentations

We held two online presentations to detail our proposed changes and give stakeholders an opportunity to ask us questions. 

Presentation recordings

Presentation one - Workstream one briefing and Q&A

 

Presentation one slide pack

Presentation two - intra-regional allocator (IRA) proposal and Q&A 

Presentation two slide pack