NZ Industrial Landowner Plans $110m Solar Rollout

New Zealand’s largest industrial landowner is set to invest over $110 million in a rooftop solar and battery storage rollout it says will lower  production costs for local and export firms while reducing pressure on the national electricity grid at peak times. Over the next decade, the  initiative will see up to 170,000 solar panels installed across the group’s industrial rooftops, creating up to 85MW of rooftop solar capacity,  along with battery storage systems to store surplus generation.

Calder Stewart has more than 900 hectares of zoned industrial land across Auckland, Canterbury, Otago and Southland, giving it one of  the country’s largest platforms for distributed energy generation. Its energy arm, Calder Stewart Energy, has already installed solar  systems across 17 industrial sites, covering over 152,000m2 of roof space and capable of generating up to 3.6MW at peak output.

The systems are expected to generate about 4.2GWh of electricity a year, equivalent to the annual power use of more than 500 homes. Sam Stewart, Calder Stewart director, says sector-wide adoption of rooftop solar across the country’s industrial sites could save millions of   dollars in avoided transmission and distribution-related costs, while reducing the need for additional grid investment. He says network  losses typically add around 5% to 10% to the amount of electricity users pay for, meaning industrial businesses are effectively paying for    more power than they consume onsite.

Stewart says solar will now be integrated as standard into the company’s new industrial developments, while the bulk of existing buildings  are expected to be retrofitted within the next 12 months. He says reducing the delivered cost of power could help lower the cost of  producing goods for local and export markets, particularly for manufacturers, logistics firms.

Stewart says the company’s move into rooftop solar reflects a shift in the way industrial buildings are expected to operate as New Zealand   businesses electrify transport, heating and production systems.

The planned battery rollout would allow more solar power to be used onsite and help reduce demand from the grid during morning and  evening peaks. Stewart says batteries could also play a wider resilience role by reducing pressure on local lines networks during periods   of  high demand. “The two peak periods in New Zealand are first thing in the morning and around six o’clock at night. If power has been  stored onsite, or batteries have been topped up overnight when electricity is cheaper, that power can be used instead of drawing from the  grid at peak times,” he says.

The company’s solar strategy is being integrated into its property development model, with new buildings designed from the outset to   support energy generation. The rooftop solar programme forms part of a broader energy strategy for the company, which is also exploring  standalone utility-scale wind generation across parts of its wider land development platform. Stewart says more New Zealand commercial  and industrial property owners need to start considering onsite generation as part of their longterm strategy.