A potential power outage is looming in the chilly air

Many parts of the country have seen temperatures dropping below zero - with an early season cold snap.

Electricity grid operator Transpower's warning households to limit power use between 7 and 9 am where possible.

It suggests turning off lights and heaters - and delaying use of appliances.

Contact Energy Chief Executive Mike Fuge says wind needs to play a larger role in our system - but we do have a strong hydro system.

He says we might need to look at increasing the operating range of hydro, things like batteries, and restoring confidence in the gas industry.