As most in Hawke’s Bay well know, flooding of Transpower’s critical substation during Cyclone Gabrielle was the cause of electrical failure – and with that communications failure – through the Hastings and Napier districts. Most of Hawke’s Bay’s electricity is provided via interconnection at the Redclyffe grid connection.
Transpower now plans to invest $47.0 million to rebuild its Redclyffe substation to better protect Hawke’s Bay’s electricity supply against flooding and earthquakes.
The national electricity transmission grid owner submitted a proposal to the Commerce Commission this week for approval to rebuild the main 220kV switchyard on the existing site, raising essential equipment out of the reach of potential flood waters.
“The events of Cyclone Gabrielle were an important reminder of how vital it is to invest in the long-term resilience of our electricity infrastructure. Transpower’s proposal to rebuild and elevate key assets at Redclyffe is a critical step forward for the electricity security of supply in Hawke’s Bay,” says Jason Larkin, Unison’s Group GM for Customer, Commercial & Regulatory.
“We’ve worked closely with Transpower to ensure the proposed upgrades reflect the lessons learned from Gabrielle and align with our shared commitment to building a resilient energy system that can withstand future extreme weather and seismic events. This investment will go a long way in helping protect our communities, our economy, and the region’s confidence in its energy future.”
In the meantime, Transpower has already completed significant work at Redclyffe substation to improve security of supply in the region since Cyclone Gabrielle. Interim upgrades to the 110 kV switchyard were made in 2023 to make the equipment there more resilient to flooding, and an interim 220 kV control room has also been installed above the flood level. A new 220 kV/110 kV interconnecting transformer is currently being installed that will significantly boost reliability of electricity supply in the region.
Transpower’s Executive General Manager Grid Development Matt Webb said: “Residents can be confident that our interim upgrades have protected their power supply, and the work we’re proposing now will make Redclyffe substation flood resilient to a 1-in-450-year flooding event and much more resilient to earthquakes.
“We believe this is the most cost-effective approach that also takes into account growing demand for electricity in the region. We have strong support from key stakeholders for our proposal and we look forward to the Commerce Commission rigorously testing our plans and costings.”
Once the Commerce Commission approves the proposal, Transpower expects to start the work in October 2026 and finish by December 2027. The work can be completed without any impact to local electricity supply.
More background on the planning is here.
Commerce Commission to test and approve in due course? Yet they expect to start work in 2026. Once a “Commission” gets hold of a project how long before they make a decision – could be years away – they’ll have to set up a Committee and elect members to it, discuss ways and means, draw up an agenda and so on and so on. I could be a bit biased but anything with a Government department or similar does seem to drag out due process for longer than any private institution
Simply build an earthen wall around the entire Redcliffe Station high enough to stop flooding. Plus a suction pump inside to pump away a heavy downpour of rain.