Npower is continuing with its application for a “fuller” court hearing to address “important issues” raised by Ofgem’s collective switching trial process, Utility Week understands.

On 24 September, the energy regulator ordered the big six supplier to allow 100,000 of its customers to join a larger collective switching trial.

Ofgem has been in discussions with Npower about the company’s compliance with obligations under standard conditions in its supplier licence.

The regulator said Npower’s refusal to participate in the “active choice collective switch autumn trial” was cause for concern and led to a provisional order being issued last month.

Npower expressed disappointment at the time and said that at the “final hour” it had not been able to agree some “detailed points” with Ofgem.

The supplier, which was yesterday given final clearance from the Competition and Markets Authority (CMA) for its proposed merger with SSE Retail, had said it was ready to undertake a collective switch trial of 50,000 customers but that was delayed because of the provisional order.

The switching trial is a “flagship” Ofgem policy in response to the recommendations made by the CMA following its investigation into the energy market between 2014 and 2016.

Ofgem introduced powers to oblige suppliers to participate in its consumer engagement trials after the investigation.

The regulator applied to the High Court on 27 September for an injunction compelling Npower to comply with the terms of the provisional order.

The High Court heard Ofgem’s application last week on 4 October and granted the injunction the next day.

Npower must now allow 100,000 of its customers to join Ofgem’s next collective switching trial.

A spokesperson for Npower told Utility Week: “Npower remains committed to improving customer engagement. As per the court ruling on Ofgem’s application for an urgent hearing, we have sent letters to around 100,000 customers to inform them they’ve been selected to take part in Ofgem’s trial and have the right to opt out.

“We are continuing with our application to court for a fuller hearing to address the important issues raised.”

Ofgem said this is “good news” for customers as it wants to continue testing ways to help people who are on “expensive default deals” to save money through switching.

In the regulator’s previous trial of a simplified collective switch more than 20 per cent of consumers switched suppliers.

“All suppliers need to live up to their responsibilities to help all customers get a better energy deal,” a spokesperson for Ofgem said.

Ofgem ran its first trial of a simplified collective switch involving 50,000 customers from Scottish Power earlier this year.