Updates to the vectorised scheduling, pricing and dispatch model

The Electricity Authority is updating the vectorised scheduling, pricing and dispatch model (vSPD) to reflect upcoming changes to the scheduling, pricing and dispatch (SPD) model.

vSPD is a replica of the SPD model, the mathematical pricing and dispatch engine used in the New Zealand electricity market. A range of electricity market participants and analysts use vSPD to simulate and analyse market outcomes.

On 23 June 2026, the SPD model will be updated to:

• implement the new tie-breaker methodology
• introduce a temporary solution to prevent non-physical battery energy storage system (BESS) dispatch
• implement other minor updates.

The updated SPD model formulation will be published as SPD Model Formulation v16.0.

We are currently updating vSPD to incorporate these changes, while maintaining compatibility with data from the start of real-time pricing on 1 November 2022. This vSPD update will also add a mapping set to the daily GDX files to help identify where the constraint preventing non-physical BESS dispatch needs to be applied.

We expect these changes to be ready by 3 July 2026. Until then, there will be differences between the solutions produced by SPD and vSPD.

For any questions, please contact info@ea.govt.nz