More than 80 per cent of homes are now using at least one energy-efficient lightbulb , according to an Electricity Commission report.

The report, conducted for the commission by the Building Research Association of New Zealand (Branz), showed 84 per cent of homes had at least one compact fluorescent light (CFL), and an increase of five more bulbs per home than in 2004.

The survey included 140 homes, drawn from the five major urban population centres and eight cluster sites throughout the country.

It showed electricity savings were the key motivation for New Zealanders purchasing the bulbs.

"A good quality CFL uses 80 per cent less electricity, so New Zealanders are saving over $100 in energy costs over a bulb's lifetime," Electricity Commission chairman David Caygill said.

"While incandescents cost only around $1, they last for just 1000 hours compared to 6000 hours for a CFL costing $7."