Solar developer unveils plan for “world’s deepest” undersea cable to link Australia and NZ grids

The founders of New Zealand solar developer Far North Solar Farm have announced an ambitious plan to build a 2-3GW high-voltage direct current (HVDC) subsea cable between New Zealand and Australia.

Designed to facilitate the trade of electricity between the two countries, the 2-3GW HVDC submarine cable would extend 2,600km across the Tasman Sea and help to increase generation and transmission capacity in both markets.

It would also support the increase of wholesale supply and retail competition, and accelerate the development of renewable energy in the two countries.

Taslink is the brainchild Australia’s John Telfer and New Zealand’s Richard Homewood, who founded Far North Solar farm in 2019.

Expected to cost upwards of $10 billion, the subsea cable would link the two countries from a point south of Auckland in the north of New Zealand’s North Island, to Newcastle on the New South Wales central coast.

The cable would be both the deepest and longest of its kind in the world and would be able to take advantage of the two countries’ close geographic and temporal proximity.

“The thing about New Zealand and Australia is that we have a two hour time difference, so we have a morning peak followed [two hours later] by Australia’s morning peak,” Richard Homewood told Radio New Zealand.

“We also have our peak demand in winter time (for heating), when we have cold and dry winters, whereas Australia has the highest demand on hot days in summer (for cooling).”

These sympathetic parallels would see Taslink buy power from one country at a cheaper rate and sell it to the other, and allow surplus Australian power to be traded to New Zealand when it’s needed, and vice versa.

“We will be purchasing power from the electricity markets in both countries, so we will have generators in New Zealand producing power that could be purchased by Taslink and sold into the Australian market,” Homewood continued.

“On the same way you could have generators in Australia… Say, solar, because Australia has an abundance of daytime solar.”

Homewood also believes that Taslink could be an answer to New Zealand’s increasing power prices, and used an example from 2024 to demonstrate this:

“If we take last year as an example and we look only at the month of August, in relation to that period our independent advice indicates Taslink could have saved New Zealanders $400 million on power costs in the month of August alone,” Homewood said.

Speaking separately on NewstalkZB, Homewood explained how he envisioned ownership of such a massive project to work.

“From an ownership perspective, our focus has always been on making sure the cable can wash its own face,” Homewood said.

“We’re not going out and asking for government funding, but we are aware of the fact that it will become a very integral and important part of both electricity markets and there may be some desire for government ownership potentially on one side or the other. But again, we’re not going out and asking for that. We’re making sure it just stands on its own.”