Big electricity companies are being accused of delaying new technology that could save consumers millions in power bills.
The accusation comes from the Parliamentary Commissioner for the Environment who has released a report on the issue.
New Zealand companies are updating 70-year-old electricity meters and expect to have installed 1.3 million "smart meters" in homes within four years.
However, Commissioner Jan Wright says their intelligence serves electricity companies mainly, permitting functions such as remote control meter reading and profiling of customer needs for marketing purposes.
Dr Wright says meters could be fitted with microchips allowing them to turn appliances on and off, depending on how dear the power is, saving customers between $25 million and $123 million a year.
The report says this could moderate electricity demand, helping householders' bills, deferring the need to build new power stations and reducing greenhouse gas emissions.
Most electricity companies have not replied to these concerns.
However, one of the largest, Contact Energy, says its meters could have the microchips added later when appliances are smart enough to take them.