It comes just days after similar legislation was scuppered at Westminster.
Big Six Rapped On Customer Service
Consumers are continuing to receive a poor deal from the Big Six energy suppliers, with smaller providers scoring far higher for the fourth year in a row, according to an annual survey.
The six largest companies, which account for 90% of the market, all ranked towards the bottom of the table in the latest Which? energy company satisfaction survey.
Npower achieved the lowest score for the fourth year running with 35%, rating the worst for its complaint handling and customer service.
Scottish Power achieved a slightly higher score (41%), below EDF Energy (49%), British Gas (49%), E.ON (50%) and SSE (50%).
Scottish Power and Npower both fell well below the British industry average of 48%, while Spark Energy was the only smaller supplier to score as poorly as the Big Six with 50%.
Consumers ranked Ecotricity the best supplier with a score of 84%, closely followed by Good Energy (82%), Ebico (81%), Ovo Energy (80%), Utility Warehouse (76%) and Flow Energy (73%) - all smaller independent providers.
Which? rated companies on criteria including value for money, customer service, complaints handling, clarity and accuracy of bills and how they help their customers to save energy.
It based customer scores on overall satisfaction and the likelihood of recommending the company to a friend.
The last three Which? annual surveys have all seen smaller suppliers rank higher than their Big Six counterparts.
The watchdog noted that the overall customer score for energy companies improved from 41% last year to 48%, but said this was still low compared to some other products and sectors it investigates.
The survey found suppliers were still failing on the basics of customer service such as dealing with complaints or ensuring bills were accurate and clear.
Which? executive director Richard Lloyd said: "For the fourth year running, smaller suppliers are wiping the floor with the Big Six on customer service.
"The large energy firms, which dominate the market, need to up their game as millions of customers deserve better.
"We need the Competition and Markets Authority to propose radical remedies to fix this broken market.
"Instead of waiting for the outcome of the competition inquiry, companies should make immediate improvements to help restore trust among their long-suffering customers.''
The survey follows Scottish Power, British Gas and E.ON cutting household gas tariffs in the face of pressure to pass on the falling cost of energy on wholesale markets.
Energy firms have come under pressure from politicians as well as regulator Ofgem to pass on the benefit of sharply lower wholesale prices.
:: Which? surveyed 9.404 UK energy bill-paying adults in September and October.
The officers were targeted as they responded to a call in the Knightswood area of Glasgow on Sunday night.
Jurors watched CCTV footage of Stefano Brizzi talking to officers at Lewisham police station following his arrest on April 7.
10,000 watched Andy Murray Live at the SSE Hydro in Glasgow last month.
Most Viewed Pictures On Heart
Recently Played Tracks
To listen live, choose your preferred location:
Deposit £10 to get a £40 Welcome Bonus - That's £50 to play bingo, slots and more!*
Over 50 tracks to make you feel-good. New album out now...
Find your local four day weather report here.
Make Heart the soundtrack to your day and you could be a winner with great prizes up for grabs throughout the day.
Find out more about some of the companies advertising on Heart Scotland- East.