Stewart Island Electricity Supply Authority

The Stewart Island Electrical Supply Authority (SIESA) is an organisation run by the Southland District Council on behalf of the residents on the Island.

The Southland District Council has contracted PowerNet to manage the electricity assets on its behalf and within the guidelines of the management contract.

SIESA was formed in 1987 by the Southland District Council (formerly the Stewart Island County Council) to ensure that businesses and homes had a reliable power supply that reduced the impact on the Island's environment where possible.

The existing plant that generates the power for the Island are diesel generators which are relatively expensive and are aging. The Southland District Council in conjunction with Righthouse are currently investigating long term sustainable energy options for the Island in an effort to reduce the cost of electricity to the Island's residents.

The SIESA network assets include 30 km of overhead lines, 10 km of underground cables and 35 distribution transformers with a distribution capacity of 2 MVA with in excess of 420 customers connected to the network.

Contact details:
SIESA
C/- The Southland District Council
PO Box 903, Invercargill 9840
Telephone: 0800 732 732