Electricity distributor Vector has taken advantage of roading upgrades along State Highway 1, between Warkworth and Wellsford including the new motorway, to help future-proof supply to the area.
The power company is responding to growth predictions for Warkworth, which will see significant increase in customers, from 16,000 at present to 25,000 over the next 30 years.
The area’s current power supply comes from Transpower’s Wellsford grid exit point via two 33kV overhead lines, with a single 33kV overhead line then heading to Snells Beach and the Mahurangi Peninsula, as well as Kawau Island.
Growth in Warkworth means that should one of the current lines fail, such as during a winter storm, the remaining line would likely become overloaded.
Vector has chosen to lay a third 33kV underground cable to meet future demand rather than upgrade the existing supply. However, it wants to defer this upgrade for at least three years and is instead looking at outside assistance to flatten demand at peak times and cover shortfalls in the event of line failure.
In the meantime, two large-scale battery energy storage systems have been installed and are operating to manage demand and add more resilience in case of an outage.
In January, Vector called for registrations of interest from outside companies to help manage the loading on the lines by using non-wire alternatives (NWA’s). NWA is a catch-all term for non-traditional solutions to network issues including distributed generation, energy storage, demand-side management, demand response, and digital network software and controls.
NWA’s normally include battery storage, and possibly generators, as well as microgrids which incorporate renewable energy such as wind power and solar arrays with batteries.
Vector estimates a total of three to five megawatts of power are needed to alleviate current network constraints, and has been seeking to buy this from these new suppliers in one megawatt blocks.
This additional power will be used to meet demand across the broader Warkworth network, which extends from Ti Point to Silverdale and west to the Kaipara Harbour, for the next three or more years.
It will also augment the supply for Snells Beach, Mahurangi Peninsula and Kawau Island from 2026 and Warkworth from 2028 when new development begins to impact demand.