The Energy Efficiency and Conservation Authority is launching a campaign to encourage households to change to power-saving light bulbs.
The authority says one in six homes in New Zealand have no energy efficient bulbs.
With the onset of winter, it says many homes are still using the older style light bulbs - even though they are significantly more expensive to run - and the average New Zealand home could save $171 per year if they change to energy efficient ones.
However, it concedes the higher price of the bulbs may be discouraging the public. Energy efficient bulbs cost $7 to buy compared with $1 for traditional bulbs.