Enquiry into manual price publication for trading period 31 on 26 February 2013
The provisional price schedule contained infeasible prices at the Studholme and Oamaru market nodes in trading period 31 on 26 February 2013.
|Stage: 1 (Enquiry)||Status: Complete||Date commenced: 1 March 2013|
The cause of these infeasible prices was a binding transmission security constraint in the Otago region.
Attempts over the next day or so to resolve the infeasibilities and publish final prices were unsuccessful. In accordance with clause 13.164 of the Code, the pricing manager ultimately decided to publish prices based on manual calculations.
Manual price calculation ought to be a last resort measure as it represents a departure from the efficient pricing delivered by the market clearing engine (SPD).
After reviewing the events of 26-28 February 2013,we recommend that the system operator modify its procedures for resolving price infeasibilities.
A model-based approach would have easily remedied the recurring infeasibilities relating to trading period 31 on 26 February 2013 without resorting to manual price calculations.
Manual price publication enquiry
Last updated: 3rd May 2013