Citizens Advice has been accused by app-based energy supplier Pure Planet of using “arcane and potentially flawed methods” to calculate its star ratings for energy companies.

The energy supplier was ranked fourth from bottom in the ratings which have been released today (15 March).

Pure Planet, which customers can contact via an app, scored zero for ease of contact as the supplier does not offer customers a telephone number.

The company however argues that its app offers customers 24-hour care through its app “chatbot” and calls customers “when needed”.

Co-founder of Pure Planet Steven Day said: “Citizens Advice has a duty of care to the public, to provide fair and transparent advice to consumers. Yet in this case, it has failed to do so.

“It is using arcane and potentially flawed methods to calculate ratings for energy companies.

“Being an app-based supplier is inherently different from traditional energy services providers. But this does not mean that an app cannot and does not offer high standards of customer service.

“Instead of having a phone number open for only part of the day, like many other suppliers, Pure Planet has a digital service available 24 hours a day, 365 days a year.”

In response Gillian Guy, chief executive of Citizens Advice, said: “While the market is changing and an app-only model will work well for many people, the lack of a phone line puts customers at risk.

“Energy is an essential service, when things go wrong the first thing many people will want to do is pick up the phone.

“We believe the rules are clear that firms should offer a phone service and that this remains vital for many consumers, particularly those in vulnerable circumstances.”

The regulations require suppliers to make it easy to contact the supplier and to have customer service arrangements which are “complete, thorough, fit for purpose and transparent”.

In December Ofgem published its final decision on modifying supplier licences to introduce five “narrow principles”.

In regards to communication, while the rules do not prescribe telephone service provision, Ofgem says it expects suppliers to make it easy for consumers to contact them and to act promptly to correct any mistakes.

It adds: “Suppliers who opt for innovative solutions such as online-only models, need to ensure their model provides adequate levels of protection for customers in all circumstances, including where very short response times are needed because of the urgency of the issue.

“We do note that there are specific obligations for suppliers to offer contact via telephone as part of their complaints handling procedures, as well as certain other prescriptive rules.”