NSW families who have moved from a single rate to a "time of use" electricity plan in an effort to cut costs may actually end up paying $370 more each year, new research shows.

With the rollout of smart meters across the state, energy companies are increasingly pushing customers onto flexible pricing plans, where they can charge higher rates – sometimes quadruple the base amount – during peak periods.

While "time of use" plans may seem like the budget-friendly option, research by Canstar Blue found the average five-person household on the Ausgrid network in NSW would actually be paying $92 more each quarter, or $368 more a year, than if they were on a single rate plan.

It based its calculations on the assumption that the household would use 30 per cent of their energy during off-peak times, with another 30 per cent spent during the shoulder periods and 40 per cent during peak periods.

It used the average rates offered by the top five energy retailers – AGL, Origin Energy, EnergyAustralia, Dodo Power & Gas and Simply Energy.

"We went into this expecting to be able to report how much consumers could save on time-of-use tariffs," said Canstar's Simon Downes.

"To find out people are actually likely to end up paying more came as a shock."

Flexible pricing has become a popular option as smart meters are rolled out across the state. From July, any new meters installed in NSW homes must be a smart meter.

Smart meters are digital devices that electronically record energy usage and transmit the data to the utility operator in real-time, allowing retailers to apply different rates depending on the time of day.

But a Canstar survey found there's still considerable confusion around the meters, with only 68 per cent of households with a smart meter knowing what type of tariff they are on.

To be fair, Canstar recalculated the costs, basing it on a household spending 40 per cent of its energy during off-peak hours, and decreasing use during peak hours to 35 per cent and shoulder times to 25 per cent.

"Even if households could considerably adjust their energy usage habits in favour of off-peak prices, time of use tariffs still work out to be more expensive, this time by around $50 per quarterly bill, or $200 per year," it said.

A family would only start seeing savings if they were able to reduce their peak time energy usage to about 25 per cent of their total electricity consumption. But this would only save them about $15 a quarter.

Janine Young, Energy and Water Ombudsman NSW, said an analysis of tariff-related complaints didn't reveal a "significant complaint issue", however she expected this to change with the smart metre rollout.

"Customers often come to EWON not knowing what tariff they are on, 'time of use' or single rate, and complain about a high bill or other complaint issue not realising it is tariff-related," she said.

"Retailers need to educate customers about tariffs and obtain explicit and informed consent when placing customers on 'time of use' contracts."

Retailers typically consider the peak period to be between 2pm and 8pm on weekdays, and off-peak to be between 10pm and 7am on weekdays and weekends. In between, they charge shoulder rates.

Fairfax Media has sought comment from AGL.

EnergyAustralia, on its website, said flexible pricing reduced the strain on electricity networks during peak times. This could reduce the need for infrastructure upgrades.

Ausgrid said "time of use" pricing provided incentives for households to save money by shifting their usage to less expensive periods.

Some of the ways a household could maximise the benefits include using the dishwasher before going to bed rather than after dinner and using the clothes dryer on the weekend.