The waste company remains confident it can still recoup compensation for late delivery of the project.

But this morning it revealed it had doubled the provision against its full settlement total from £8m at the half year to £16m.

In a stock market trading statement, Viridor parent group Pennon said its three new energy recovery facilities at Glasgow, Beddington and Dunbar had now all progressed through commissioning to service commencement ahead of full operation.

It added that optimisation was ongoing and operations would continue to ramp up over the next 18 months.

Pennon said it would rigorously pursue its claim against builder Interserve Construction, which remained solvent when Interserve plc was placed into administration.

The firm said: “Given the recent announcements regarding Interserve plc entering into administration we are seeking further clarification regarding the financial position of Interserve Construction,  the ongoing operating company with whom we contracted, which may change the level of provision to be announced with the full year 2018/19 results on 30 May 2019.

“We will continue to pursue recovery of all amounts due from the operating subsidiary Interserve Construction  and will take all the necessary legal and procedural steps to achieve this.”