The Electricity Authority has found that no undesirable trading situation occurred on the night of a massive power outage in August.
Photo: RNZ / Diego Opatowski
Several small retailers claimed two generators, Contact and Genesis, were responsible for the blackout that left 34,000 homes in the dark on the coldest day of the year.
Electricity demand reached an all-time high on 9 August, combined with insufficient generation, it resulted in blackouts to some parts of the country, as power distributors responded to Transpower's demand to reduce the burden on the national grid.
In its preliminary decision, the authority said while some decisions could have been different, the choices made by Contact Energy and Genesis Energy were reasonably open to them, given the context and information available to them at the time.
"Our preliminary view is there was no situation that threatened or may have threatened confidence in, or the integrity of, the wholesale market," authority general manager legal Sarah Gillies said.
It also found that the actions and the decisions made by the grid operator Transpower were not perfect, but generally appropriate because of the risks at the time.
However, this was not the end of the matter as the authority was continuing to investigate what happened through separate investigations of alleged breaches of the code, including a possible breach of the new trading conduct rule.
It was also carrying out phase two of its review of all generators in the 9 August event.