Transpower says recent electricity generation simulations should not trigger panic, over declining gas supply.

Two of three tests show improvements, looking a decade ahead into how our systems will cope with demand.

But the third - the winter energy margin - finds worsening conditions, year-on-year.

Transpower's James Kilty says it's not a big deal.

"The tests include a buffer, so the fact that we're dipping slightly below the buffer does not mean that there'll be electricity supply shortages next year."

LISTEN ABOVE