From sunlight to savings: how Kaiwaiwai Dairies are maximising energy efficiency with solar

The power of solar 

Several years ago, Kaiwaiwai began investigating ways to reduce operational costs and impact on the land and resources. Energy, a major line item in their budget, quickly emerged as a prime target for innovation. After assessing both wind and solar options, solar clearly outperformed on reliability, economics, and ease of integration. 

“Although it’s quite windy here, wind generation didn’t stack up, but solar definitely did,” says Bichan. 

In 2021, the team installed a 54 kW ground-mounted solar PV system near their switch board for optimal access and minimal infrastructure disruption. The system consists of 144 panels feeding two 27 kW inverters. This location and design allow for efficient integration into the existing grid and easy monitoring. 

“When we installed the panels, the cost and performance matched the quotes — that doesn’t happen often in farming,” Brasell says. 

“The financial benefits have been straightforward: we’re saving money on power, which is only going to get more expensive. Plus, there are now loans available that make the investment easier.” 

He sees solar as a no-brainer, especially for dairy farms with large power demands. 

“If you’re having a good year, it’s a great time to invest. Not just for cost savings, but to future-proof the farm against rising prices and meet customers’ expectations."

Designed for practicality

Kaiwaiwai’s solar system was installed by a local renewable energy specialist with a history in off-grid and hybrid systems. The process was straightforward, and apart from an early inverter failure and one instance of irrigator-related damage, the system has run reliably. 

Initially, the team considered installing panels on the dairy shed roof, but the roof wasn’t solid enough to take the weight of the panels, and the angle wasn’t optimal for maximum sun interception. Ground mounting allowed easy access for maintenance and optimal panel orientation. 

The farm prioritises proximity of panel placement to the switch board rather than specific machinery locations to streamline electrical connections. “Future panel placement will still be close by, aiming near the switch board,” says Bichan. 

Performance-wise, the system produces close to its 54 kW capacity on sunny summer days, and even on gloomy days, it delivers between 12 to 18 kW, ensuring consistent energy supply year-round. 

“The panels are low maintenance. They’re fenced off to protect from stock, and occasionally we weed around them to avoid shading,” Bichan explains. 

With over 90% of generated electricity consumed on-site for processes like milking, milk chilling, irrigation, and effluent management, the need for battery storage is currently minimal. 

Building on success 

Kaiwaiwai is exploring expansion of solar capacity combined with battery storage, as a next step to better manage energy use and reduce grid reliance. Proposed strategies include shifting high-demand processes — like hot water heating and milk cooling — to daylight hours when solar generation peaks. 

Proximity to the main switch board remains a guiding principle for new installations to simplify electrical integration. 

“We’re always learning, always adjusting. The world is changing — and we need systems that can flex with those changes,” says Brasell. 

 “This is a journey with many steps. The solar panels are one of the bigger items, but we also manage water quality with wetlands, monitor soils, climate, effluent, and stock, and keep refining all these areas to improve efficiency and profitability.”