A $1.4 billion upgrade could be on the way for Transpower's Cook Strait electricity cable.  

The 610 kilometre link is a transmission system connecting the North and South islands, installed in 1991. 

The existing cables are likely to reach their end of life in the late 2030s.  

Energy Resources Aotearoa CEO John Carnegie told Mike Hosking the Commerce Commission will need to review that. 

He says they’ll need to ensure the numbers are robust and the programme executable.  

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