Even on a cloudy day, solar panels are still generating energy — typically 40% to 60% of their capacity. Image supplied
New Zealand households face power bill increases of up to $240 a month over the next five years as the country grapples with a $42 billion infrastructure upgrade.
Rory McCarthy, who is chief commercial officer and partner in Lightforce Solar, says there is a way out of the crisis.
“This is the moment to educate, empower and spark conversation about energy independence. Power price hikes are hitting households, misinformation is rife and Kiwis are actively seeking alternatives.”
Power prices have surged 40% over the past five years, driven by ageing infrastructure and the country’s continued reliance on coal and diesel for generation.
McCarthy says whenever you put in a new generating system, you have to spend 75% of that value on transmission. The country also loses 14% of its energy in transmission across its long, skinny network, losses that are, in part, given up as heat in the wires.
One of the biggest misconceptions about solar in New Zealand is that it needs sunshine, but McCarthy says it’s actually about light, not heat. Ultraviolet light reaches solar panels even through clouds. New Zealand gets around 1500 hours of quality UV per year — which is not far behind the United Arab Emirates’ 1630 hours, despite the Gulf nation having 340 days of sunshine.
Even on a cloudy day, solar panels are still generating energy — typically 40% to 60% of their capacity. Northern European countries like Germany, Denmark and Poland have huge solar plants despite having similar or worse weather than New Zealand.
“We’ve been late to the party. But in some ways, that’s not a bad thing,” McCarthy says. Around 80% to 85% of residential solar systems sold here now include battery storage, unlike earlier adopters like Australia, where systems were installed without batteries, causing voltage fluctuations on the grid. The earlier Australian experience is another source of popular misconceptions about solar’s potential.
McCarthy says solar can cut bills by 25% to 50% or more, with homeowners typically seeing payback on their systems in five to seven years.
The benefits of solar are equally important for businesses. “Using your own power on-site is a huge saving. You can plan into the future with power being much more of a fixed cost than an increasing variable hurting the profitability of your business,” he says.
Agricultural operations are particularly well-suited to solar, McCarthy says. Pumps supplying water to fields and livestock use huge amounts of energy. Unlike residential homes, farms aren’t limited by roof size. Solar systems can go on cow sheds, ground mounts, or, for commercial sites, in car parks. Lightforce has installed systems on farms, including one for Kevin Barrett, father of All Blacks Beauden and Scott Barrett.
“Most people think it’s just a solar panel. It’s actually not only a panel, it’s a system.” A complete installation involves roofing structures, ducting, mounting systems, inverters to convert DC power to AC and batteries that require hybrid inverters to balance current from panels, storage and the grid.
“When you install a solar system, you are turning your roof into a power station. So you do want to make sure that if you’re turning your rooftop or car park into a power-generating asset, it’s best to work with a company that’s got the credibility, the references and the ability to do this effectively. One that has proven itself and has that track record.”
Using your own power on-site is a huge saving.
McCarthy says Lightforce was established in 2013. The company now operates seven hubs across the country, from Kerikeri to Christchurch, with 106 staff covering sales, design and engineering, installation and project management. It’s responsible for 20% of all solar installations in New Zealand and has nearly 10,000 homes on its books.
McCarthy returned to New Zealand in April this year as an investor and partner after 25 years working abroad, most recently as chief operating officer of Yellow Door Energy in Dubai, where he oversaw 350 megawatts of solar projects across the Middle East and South Africa.
New Zealand’s electricity network faces constraints that limit solar adoption. Households and businesses need to be able to feed excess power back into the grid as well as draw from it, but export limits are capped at 5–10 kilowatts depending on location, compared to 20–25 kilowatts in countries like Australia, California and the Netherlands. Getting a distributed generation permit takes several weeks, compared to 48 hours in some neighbouring countries.
McCarthy says distributed solar generation with battery storage could actually help defer some of that $42 billion infrastructure spend. By injecting energy into the grid at multiple points across the network rather than transmitting it hundreds of kilometres, the pressure on ageing transmission assets is reduced. The approach has worked in countries like Germany, where distributed solar has reduced strain on their grid.
Beyond bill savings, solar offers other benefits. Charging an electric vehicle from rooftop solar means free transport energy. “If families are filling up four or five times a month at $300 at the pump, that’s $1500 - that’s a lot of school fees, or a family holiday, or food on the table,” McCarthy says.
Solar also provides resilience during extreme weather events. McCarthy points to Nelson’s recent power outages, where businesses with their own generation were able to keep functioning, including the local hospital.
McCarthy says solar is viable even for homes with old roofs or limited space. The technology now includes innovations like carport solar and EV fast-charging integration. Systems require maintenance, cleaning panels to prevent efficiency losses from pollen and algae growth. He says all that can be covered with service contracts and energy generation warranties.
He draws a parallel with Norway, a major oil exporter that has embraced solar and electric vehicles. “Why would we want to pay, as a nation, any more money to the Arab nations in the Gulf than we have to? It doesn’t make sense when there are alternatives that are far cheaper, far more efficient, better for the economy, better for the air we breathe, better for protecting the natural environment, which we all love.”
Lightforce Solar is a sponsor of the Herald’s Sustainable Business and Finance report