The Competition and Markets Authority is set to carry out an in-depth investigation into the UK energy sector.
Set to take place over the next 18-months, the competition watchdog's investigation will cover a range of concerns, including how the big six energy companies continue to maintain supply market dominance more than 14 years after the energy market was privatised.
Its investigation will also consider "how suppliers might exploit and influence the behaviour and perceptions of customers to their advantage," and the extent to which domestic energy price rises seem to be associated with a rise in wholesale energy costs.
The CMA stated: "We propose to consider the evidence that retail suppliers (while not reaching agreements on their behaviour) are tacitly coordinating, in adopting strategies and behaviours to their mutual advantage."
Having concluded that the element of competition wasn't working in the energy sector, regulator Ofgem outlined plans to refer the industry to the CMA back in March (2014).
Chair of the Energy Market Investigation Group, Roger Witcomb, stated: "Given the importance of energy supply to households, businesses and the economy, we very much encourage submissions on the issues we have identified and whether these cover the areas we need to investigate.
"We are looking to identify the underlying causes, at both wholesale and retail level, which could be leading to widespread concerns that have surrounded this market in recent years - including rising energy bills, service quality, profitability and uncertainty over future investment.
Mr Witcomb then went onto add: "This is a market which is very complex so it is important at an early stage to focus the investigation on the most relevant issues."
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