In the early hours of Sunday 5 October 2014, a fire was identified at Transpower New Zealand Limited’s Penrose substation. The fire resulted in a major outage to electricity supplies in parts of Auckland. 

The fire was caused by the electrical failure of a cable joint in a medium voltage power cable owned by Vector Limited. The fire led to a widespread loss of supply due to the location of the cable joint in a trench containing a total of 3.99km of power cables in 38 separate lengths (including 19 high-voltage cable circuits, 15 cable joints and a number of control cables).

The power cables in the cable trench directly supplied over 39,000 electricity customers in Auckland. However, a total of 75,339 customers were affected by the fire because further electrical circuits had to be switched off to enable access for fire-fighting personnel. Electricity was progressively restored throughout Sunday and Monday and supply was restored to the final customers on the afternoon of Tuesday, 7 October 2014.

The Hon. Simon Bridges, Minister of Energy and Resources, noted the significance of the loss of supply in terms of disruption and cost and requested, under Section 18 of the Electricity Industry Act 2010, that the Authority carry out an inquiry into the outage.

The Authority's report and supporting documents can be found below. 

On 1 March 2016, the Authority published the implementation plan submitted by Transpower New Zealand Limited and Vector Limited.  The implementation plan and progress reports will allow us to monitor progress towards completing the recommended actions for improvement.