Final Muskrat commissioning delayed until spring as GE struggles to perfect transmission software

There has beenyet another setback for the Lower Churchill Project, with N.L. Hydro delaying final commissioning of the hydroelectric project until spring as efforts to perfect transmission software continue.

In its latest update to the Public Utilities Board, Hydro set a new target of May 31 for project completion, a two-month delay from the previous update, provided in December.

It's the latest delay in a project that is billions over budget and years behind schedule. It's also further evidence of the challenges being encountered by GE Grid Solutions as it struggles to fine-tune the computer software required to safely and efficiently operate the 1,100-kilometre high-voltage transmission line from Labrador to Newfoundland's Avalon Peninsula.

The latest version of the software was installedDec. 9, and following a series of tests, the transmission line known as the Labrador-Island Link was cleared for operations using both lines on the link on Dec. 17.

According to N.L. Hydro's update to the PUB,the software has been operating continuously at various levels, up to 435 megawatts, ever since. That's just over half of the 824 megawatts Muskrat Falls is rated to produce, andnearly equivalent to the generating capacity at the oil-fired power plant in Holyrood.

• Power now, pay later: Muskrat Falls generating station complete

But Hydro says this latest software is "not suitable for trial operations and final commissioning due to unresolved critical punches."

The Crown corporation says the software was approved for operations in order to test the stability and robustness of the software.

GE expects to have yet another version of the software available before the end of March that will be used for final commissioning by the end of May, Hydro said, and will havesix months after final commissioning to resolve outstanding software glitches, according to Hydro.

When the publicly funded project was sanctioned in 2012, the in-service cost was estimated at $7.4 billion, with completion scheduled for 2017.The cost estimate has since ballooned to $13.1 billion, and a long list of deadlines have come and gone.

Hydro announced in late November that the power station at Muskrat Falls was complete.

CBC News has requested an interview with N.L. Hydro.

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