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 Friday morning where possible.  

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

Contact Energy Chief Executive Mike Fuge told Mike Hosking that there are lots of plans and investment in growing generation capacity.  

He says Tauhara —the sixth geothermal power station near Taupo— is being commissioned, which would provide another 160-170 megawatts. 

Fuge says the cold's come a bit earlier and the project's running a bit late. 

LISTEN ABOVE 

• 'Third-world stuff': Energy minister praises chilly Kiwis' restraint amid grid crisis
• 'We're all being vigilant': Transpower issues warning ahead of tomorrow's cold snap