Why NZ’s had a break in the wind
On this day 25 years ago, New Zealand’s first wind farm started generating electricity. Over the next 14 years, we’ll need to open roughly one new wind farm each year to cut our carbon footprint – yet Olivia Wannan finds progress is patchy.
Across the whole country, just a single wind turbine started turning between 2016 and 2019 – and technically it wasn’t even a new one. It was a replacement for the faulty one atop Brooklyn Hill in Wellington.
This turbine had been the country’s first – installed in 1993, it was an experiment, meant to run for just five years.
By the time its blades stopped turning in 2010, the public had come to see it as a beloved landmark, with widespread support for its replacement. (It was replaced by a larger, 44m-high generator capable of powering 490 average homes each year.)
The ‘‘iconic’’ experimental turbine beat expectations, says Wind Energy Association chief executive Grenville Gaskell. It was estimated it might generate enough to power 80 homes each year – the reality was closer to 110.
‘‘It was the highest performing turbine of its type in the world,’’ he says. ‘‘We’re in the Roaring Forties… It’s an exceptional place for wind generation.’’
For that reason, the technology quickly won over Genesis Energy, which began construction on the very first wind farm in 1996. On June 6 of that year, the first blades on the Hau Nui wind farm in Wairarapa began to generate power.
Construction ramped up through the Noughties – 2004 remains the pinnacle of wind power in New Zealand, with 118 turbines added. Genesis extended Hau Nui by eight, and a further 110 popped up around Manawatu¯ .
Another 62 turbines joined the Brooklyn generator on the hills around Wellington in 2009, creating the annual power used by every house in the capital city. In 2011, two farms popped up in Clutha, one in Marlborough, and another in Waikato.
After that, there was a lull in turbine construction. Power companies still seem to be interested in wind, judging by the resource consents they seek. Yet just 35 turbines were erected in eight years.
Energy consultant Toby Stevenson, director of Sapere, points to the Global Financial Crisis of 2007/08, to explain the pause. ‘‘It’s after that, that demand flattens.’’
Power companies build new plants to meet extra demands for electricity. When the economy slows, so does our appetite for energy, he says.
Gaskell says businesses and homes also started to consume less energy thanks to heat pumps, LED lights and industrial efficiency work.
Wind farms became the go-to because they’re one of the cheapest sources of electricity; that they’re low carbon is a bonus.
They’re also resilient, says Genesis chief operating officer Nigel Clark. The Hau Nui wind farm is still going strong. ‘‘It’s a pretty rugged location so the fact they’ve been able to survive for 25 years is a real testament.’’
Environmental advocates have spent decades calling for renewable power stations to
replace the coal and gas burned at Huntly and other fossil-fuelled plants. But Stevenson says this idea only went mainstream with the passing of the Zero Carbon Act in 2019.
Then, last year, the Government pledged to make the grid 100 per cent renewable by the end of the decade. The offshore oil and gas exploration ban, which was announced in April 2018, also made the electricity sector take notice, Stevenson says.
Natural gas provides about 12 per cent of the country’s power each year. Coal is both imported and domestically mined, and provides about 4 per cent of our electricity – though this dirtier fuel isn’t subject to the exploration ban.
The industry says the ban has made gas companies more reluctant to invest. There have also been supply issues in gas fields.
Last year, wind’s dry run ended. Wind farm builder Tilt Renewables was busy with two projects – in Taranaki, it completed a 31-turbine farm in partnership with Genesis, known as Waipipi. It also started constructing 60 turbines in the Tararua Ranges, this time with Mercury. When completed, the Turitea wind farm will be the country’s largest.
The Climate Change Commission sees a big future for wind, as the country aims for net zero emissions by 2050. We’ll need to build 13 new wind farms (each one the size of Turitea) between now and 2035.
Helpfully, today’s turbines produce a lot more electricity and are quieter. Turitea’s new generators will be twice as tall, with blades three times as long as some of their predecessors’.
Mercury generation development manager Dennis Radich thinks the commission’s vision is doable. ‘‘We’re going to run as hard at getting as much of that as we physically can… The cost of wind has come down substantially and continues to fall.’’
Genesis – which runs the Huntly power plant as well as hydro and wind projects – has set its own carbon-cutting goals. By 2030, it wants to reduce a large chunk of Huntly’s day-to-day fossil-fuelled combustion with new renewable generation – the equivalent of another five Waipipi wind farms.
A solar array is in the works and another wind farm (perhaps a revival of a Wairarapa project at Castle Hill) is likely, says Genesis’ Clark. ‘‘Wind and solar are good, but they’re intermittent – they may not be there when you want.’’
For that reason, Genesis is also exploring a geothermal plant, a steady source of energy.
Gaskell says as well as using improved turbines, wind farm builders have learned a lot about how to work with communities and where to locate farms to minimise risks to wildlife. For example, the Waipipi project protected and restored wetlands on the site.
‘‘Some locals who were opposed now see it as something iconic and are proud of it... Support is definitely improving.’’
Today, about 80 per cent of our power comes from
renewable sources – hydro dams, geothermal plants, solar panels and wind farms. That proportion is going to rise towards 100 per cent, but at the same time, we’ll need to create more electricity to power our cars and new electrified industrial appliances.
The more wind we build, the more water we can store in our dams, to use particularly when demand soars.
The conditions appear ripe for power companies to build wind farms. But developers are still jittery. They’re keeping a close eye on the Resource Management Act reforms, Gaskell says. ‘‘One of the biggest barriers to develop wind farms is the ability to consent new wind farms.’’
The Tiwai aluminium smelter consumes 13 per cent of the country’s electricity each year. The major user’s closure announcement and then U-turn won’t have helped, Stevenson says.
Another culprit, he adds, is a quirk of the power market: the spot price of electricity is set by the most expensive generator required at that point in time. Essentially, all the solar and wind farms, geothermal plants, hydro dams and thermal power stations put in an offer to sell their electricity for a price.
Fossil-fuelled plants have to purchase their fuel, so they typically put in a much higher offer. When these plants operate, wind farms are paid the same and bank a tidy profit. Adding up these profit margins over the life of a wind farm, investors get a clear idea of how much cash they can get from building a new one.
A wind farm built today will be operating in 2031 – the date the Government wants to have closed all fossil-fuelled power stations indefinitely. At that point, we might have a large pumped-hydro station at Lake Onslow, or perhaps one near Taupo¯ , or an array of smaller batteries, or all of the above to replace them.
There’s some talk about how these projects will be constructed, but everyone’s particularly curious about how they’ll operate day-to-day, Stevenson says.
Will the Government build Lake Onslow and then turn over operations to a power company such as Genesis or Meridian, or will it ask an independent agency to run things based on public good principles? Will the hydro scheme take part in our electricity market, and how will the operators decide what to charge for this power?
This is a particular problem for independent wind farm builders (such as Tilt) because they don’t have a pool of residential and corporate electricity customers, he adds. That’s one reason to partner up with big ‘‘gentailers’’ such as Genesis and Mercury.
Solar investors will be keen for this detail as well. Wind won’t be the only solution to the country’s future electricity needs, Stevenson stresses.
‘‘The amount of generation we’re going to need, we’re going to need every solar panel, every wind turbine we can get our hands on.’’
‘‘We’re in the Roaring Forties… It’s an exceptional place for wind generation.’’ Grenville Gaskell Wind Energy Association chief executive