JUST a third of consumers are able to pick out the cheapest energy deal despite the introduction of simplified tariffs, according to a watchdog.

Which? said Ofgem's new rules for standardised tariffs were "a step in the right direction" but found two-thirds of consumers still failed to identify the cheapest deal.

The consumer group asked people to spot the best deal using the standard tariffs of the big six suppliers - British Gas, EDF, E.ON, Npower, Scottish Power and SSE.

It found a third (35%) chose correctly when tariffs were presented in line with Ofgem's new Retail Market Review (RMR) structure, made up of a unit rate and standing charge.

Of the rest, three in 10 (31%) picked the wrong tariff and a third (34%) either did not think it was possible to calculate, or did not know how to.

Four in 10 (41%) used an aid, such as a calculator or spreadsheet, yet only 50% of these people got it right.

Which? said the results were an improvement on a similar test in 2012, when only 8% could pick the cheapest deal using the old tariffs.

It said: "While the RMR structure is an improvement, our latest results show that the majority of people are still baffled".

Which? executive director Richard Lloyd called for more radical changes "to fix the broken energy market".

Trade association Energy UK said: "Energy companies have made great changes helping customers find the best deal available.

"We are pleased the survey results show an increase in customer understanding and the energy industry is continuing to work with customers and consumer groups so more people understand their bills and choices."