Staunch opposition to wind turbines keeps Stewart Island running on diesel power 

Stewart Islanders pay higher prices for their power than mainlanders, but they’re stuck with diesel for the foreseeable future after a wind turbine project was scrapped.

But why were islanders so against the turbine project?

During the past 40 years some 25 reports have looked at alternative energy sources but to date nothing has been built.

With a Government that is pro-active in encouraging people to look cleaner fuel sources to help the climate, having beautiful Stewart Island, that is renowned for its eco-tourism, run by diesel probably isn’t the best look long-term for a clean and green future.

The Southland District Council engaged consultants Roaring 40s Wind Power for the project, which had a $3.16 million backing from the Provincial Growth Fund.

The wind turbine project was canned in February, despite the fact it could have reduced the island’s reliance on diesel by about 40 per cent.

In a council-written final pre-development report, done as part of its obligations under Ministry of Business, Innovation and Employment, it outlines the staunch opposition the turbine project faced on the island.

Included in the report, a Roaring 40s consultant notes “staunch” opposition, from landowners and repeated land access issues. They had also signalled earlier that the preferred site at an airstrip (Ryans Creek Aerodrome) was expected to face opposition during a resource consent process.

The sites under consideration for the turbines were the airstrip and the next option was the Mamaku​​ Point Conservation Reserve.

The turbines would have been no taller than 65 metres, with a maximum rotor diameter of 33m and the plan was for four wind turbines on two properties at the airstrip, one privately owned property and the other was Department of Conservation land.

Stewart Island Flights director and pilot Bill Moffatt, who leases land at the airstrip, said building turbines there would have been unsafe.

Stuff asked Moffatt how dangerous he thought turbines next to the airstrip could be, and he replied: “You ask me that after someone has run into one.”

If the turbines were to be built above the level of the airstrip, to be safe they needed to be three kilometres away, Moffatt said.

Vehicles being driven to the turbine site would have been heavier than the 1500kg airstrip limit as well, he said.

Moffatt understood the turbines would only be able to work in winds up to 35 knots, and said the winds there were often more than 50 knots.

While there were a few private solar panels, running a power cable to the island was the “no-brainer” solution, Moffatt said.

A power cable has been suggested and investigated before, including in 2015 when a $36m estimate was knocked back by the council.

In June 2020, DOC, Stewart Island Flights and airstrip owner Helen Cave met.

But the next 21 lines of the pre-development report are redacted, because commercial information and free and frank opinions.

Cave owns the access road as well as the airstrip.

She told Stuff that during the planning, she kept calling the proposed airstrip turbines “mincers” because she did not think they were safe.

Cave has lived on the island for more than 50 years, owns fish sheds and the South Sea Hotel and says there is some “not in my backyard” sentiment about the turbines.

But she also said the island’s rural and urban zones were configured to present a pristine image of no visible settlements, which the turbines could negate.

If the wind turbines had been put on the Mamaku Point Conservation Reserve, Cave said she could have seen them from her house.

Stuff asked Cave if she thought the turbines would be an eyesore.

They would “offend” her for the first week, but after a month they would be no bother, she replied.

She, too, believes a cable will be the best source of renewable energy for the island.

Once the airstrip was ruled out the focus turned to the Mamaku Point Conservation Reserve but vegetation clearing for the turbines and access would have been required.

Despite five options for placing the four turbines, no solution could be found.

Reserve trustee Roy Thompson told Stuff last year that turbines would not be going on the most prominent ridge of the reserve.

The project was in a “pre-development” stage when it was shelved in February.

That stage had a $495,000 budget.

Stewart Island councillor, Bruce Ford wants the Government to help power the island.

The turbines could have been built on Crown land (the national park), Ford said.

“The Government has renewable targets and a declaration on climate change, they have to have remedies ready,” he said.

He is referring to the climate change emergency decleration, made in December.

Beehive targets include reaching net-zero carbon emissions by 2050, and the aim of making a number of government organisations carbon-neutral from 2025.

In the interim the island will continue to be powered by diesel generators under a scheme owned and run by the Southland District Council called the Stewart Island Electricity Supply Authority for the 400 islanders.

Stewart Islanders paid 60 cents per kilowatt-hour last month, while those on the national grid in Invercargill were paying about 27.94c/kWh and 32.70c/kWh at Winton.

SIESA became operational in 1988 and is powered by diesel generators, feeding 30km of overhead lines, 10km of underground cables and 35 distribution transformers.

The generators use about 360,000 litres of diesel.

Ford is hopeful that the next best chance to move away from diesel may be in piggybacking on an Antarctic data cable.

Meridian Energy has agreed to supply company Datagrid with 100 megawatts of power from the Manapouri hydro scheme, if a planned data centre is built at Makarewa, near Invercargill.

The centre could have a cable from the data centre to Antarctica, and if a power line were laid alongside it, Stewart Island could be on the national grid, paying mainland prices, Ford said.