Sun is an essential ingredient for farmers’ crops and grass, and it’s also the resource critical to a new land use tipped to spread across thousands of hectares of New Zealand pasture – solar farms.
Late last month news broke that the Todd Corporation is well advanced with plans to cover a 1022ha dairy farm southeast of Taupō with 900,000 solar panels, shipping container-sized inverters and a huge switchyard. The panel arrays will track the sun from east to west each day and Stuff reported that while about 20 staff will be employed in the operation and maintenance of the facility, once fully operational control of the solar farm will be automated, with remote monitoring of the plant from a control room.
Assuming Taupō District Council and the Bay of Plenty Regional Council grant the resource consents lodged in April, the first panels will go in later this year. All going to plan the solar farm will be fully operational by 2027, generating 400MW of electricity – enough power for around 100,000 homes.
It may sound impressive, but it is by no means unusual.
Lodestone Energy is proposing more than half a million solar panels spread across five locations in Northland, the Coromandel and the Bay of Plenty.
Adding enough electricity to the national grid to power 50,000 homes – that’s a city the size of Wanganui – Lodestone says on its website that each solar farm will incorporate world-leading bi-facial modules and single axis tracking technology. This will see the panels rotate and track the sun as it travels across the sky. Electricity will be produced from both sides of the panel, allowing the capture of energy from reflected sunlight from the ground.
The company’s first solar farm, Lodestone Two near Kaitaia, is expected to be operational in the third quarter of next year.
Two solar farms are being discussed in the Wairarapa, and a $150 million-plus farm covering the equivalent on 262 rugby fields at Christchurch airport is scheduled to be generating 150MW – enough for 20 per cent of Christchurch homes – within 5-7 years. Ultimately, planes will be able to pull up and recharge from adjacent storage batteries.
New Zealand’s largest solar farm to date – a much more modest 5,800 panel facility generating enough electricity for 520 homes – is at Kapuni in Taranaki. It came on-line in May last year.
Andrew Harvey-Green, electricity and energy sector research analyst at Federated Farmers’ strategic partner Forsyth Barr, says several of our largest electricity generators and at least 10 independent developers are at various stages of capital raising, planning and/or consenting for solar farms.
He says the cost of building solar generation has come down significantly in recent years to the point that “it’s not too far away from the cost of building a wind farm.
“On top of that, look at where electricity prices have moved in New Zealand – the cost of gas, the cost of carbon, the cost of coal has pushed those prices much higher so it’s becoming more attractive to build renewable energy,” Harvey-Green said.
While at the beginning of last year hardly anything had been announced by way of large-scale solar, “here we are 18 months later and the numbers being talked about are quite phenomenal”.
Even so, we’re chasing a trend that is already well-advanced overseas. Governments in many other jurisdictions offer subsidies for developers of renewable generation. Secondly, the closer you are to the equator, the more generation you get from solar.
“Even without subsidies, the economics [of solar farms] work better offshore than in New Zealand so they got that head start on us.”
Plenty of those offshore solar farms in Australia and the UNA are on arid or otherwise relatively unproductive land, where there isn’t the same competition for space as exists here, Harvey-Green said.
But pasture converted to solar panel use here doesn’t necessarily mean the land is lost to grazing.
Lodestone says for its solar developments, the panels will be high enough, and spaced sufficiently, to allow farming and cropping to continue underneath. The panels would even provide nifty summer shelter for cattle and sheep.
Back to the company’s website: “This agrivoltaic approach allows the land to continue to be productive, with over 85% of baseline farming yield expected when the solar farm is operational.”
Those planning the solar farm to the west of Christchurch airport’s runaways say they will be making sites available for data centres and vertical farming operators.
Federated Farmers President Andrew Hoggard is relaxed about the prospect of large-scale solar farms.
“So long as the hosting land owner is paid a fair amount for the encumbrance, nearby farms aren’t unfairly impacted by construction, and increased investment in local lines to handle the load doesn’t drive up power prices in the area, there shouldn’t be any problems,” he said.
“They seem to be focusing their interest around areas that border existing substations or other keys bits of infrastructure to minimise costs of transmission, so it’s likely they’ll be fairly targeted, not a blanket approach.”
Unlike wind turbines, which can generate a fair bit of opposition around noise and the threat to bird life and visual impact, solar farms only have that latter downside. Forsyth Barr’s Harvey-Green says that probably means they’re easier to gain resource consent for, and they’re certainly easier to build.
The prospects of these huge solar farms have been put in the shade of late by rising costs of solar panels, shipping and other supply chain disruption, so while Harvey-Green understands consents have been gained, or are in the process of being gained, for several of them, he’s not aware of a start on actual construction.
“Things have slowed down a wee bit.
“But it’s highly, highly likely we’re going to be seeing a lot more activity in the renewable energy space. For solar, it will be fairly site specific initially. I’d be surprised if we get all the ones that have been talked about built within the next 10 years but for certain, solar prospects look good going forward.”