The Stewart Island Electrical Supply Authority (SIESA) is responsible for the generation and supply of electricity to consumers on Stewart Island. SIESA is owned and operated by the Southland District Council on behalf of Stewart Island/Rakiura electricity consumers and is governed by the Stewart Island Community Board.
SIESA's network is powered by five diesel generators at a central power station and the power is delivered by 30km of overhead lines, 10km of underground cables and 35 distribution transformers.
SIESA is also investigating the possibility of alternative power generation through renewable resources such as wind and solar, with wind turbines and solar panels installed on the island last year in a trial. Right House, a subsidiary of Meridian Energy, and SIESA are partners in this trial.
SIESA also undertakes waste collection and ownership and operation of the Rakiura Resource Recovery Centre.