The Minister of Energy and Resources says it's unacceptable Transpower couldn't see how much electricity was available when power was cut on one of the year's coldest nights.
An investigation shows 34,000 North Island homes were unnecessarily without power on the night of 9 August.
The review shows electricity companies were simply responding to Transpower's demand of reducing the burden on the national grid - but the load could have been managed.
Minister Megan Woods told Morning Report one of the report's key recommendations is for better forecasting to manage demand.
"There's 18 recommendations in this report, nine of them around communications, but also forecasting, and the way in which the we can have that overview of what is available, so that we can manage demand.
"That's going to be one of the key recommendations I'll be looking at, particularly how it is that we forecast wind."
