As the window for final testing narrows, Muskrat Falls encounters new problems

Newfoundland and Labrador's long-sufferingMuskrat Falls hydroelectricity project has encountered new problemsahead of a final round of testing that must take place during thecolder months of the year.

The issues have pushed a round of high-power testing which thecompany had hoped to have completed by the end of February to lateMarch or early April, according to Newfoundland and Labrador Hydro'slatest report. And if the tests aren't completed by that time, theywon't be able to be performed until October or November.

"Testing requires elevated system loads that would beaccommodated by typical temperatures expected in March and April.Hydro expects to perform testing in this time frame," said thereport dated March 2 to the province's public utilities board.

The report said a new glitch was discovered in the software thatruns a subsea cable stretching across the Strait of Belle Isle,between western Newfoundland and eastern Labrador. Frigid Februarytemperatures have also held up other troubleshooting efforts, as thehydro company can't risk outages during extreme cold, the companysaid.

N.L. Hydro said it expects the issues to be resolved in time torun high-power tests in a few weeks, adding that there arecontingency plans in place if the software problem isn't fixed intime.

Rob Collett, the Crown corporation's vice-president ofengineering, said in a recent interview that the high-power test is the last test the project has to pass before it will finally be ready to be declared fully operational.

If it fails, the province will wait at least until it gets coldagain likely October or November, Collett said for anotherhigh-power testing opportunity, and ultimately, for finalcommissioning.

The Muskrat Falls project has long been a financial thorn inNewfoundland and Labrador's side. It was officially green-lit in2012 by a then-Progressive Conservative government, with a price tagof about $7.4 billion. Years overdue, its costs have ballooned tomore than $13 billion, a figure Premier Andrew Furey described in2021 as "an anchor around the collective souls of Newfoundland andLabrador."

The main source of recent setbacks for Muskrat Falls has been a1,100-kilometre-long transmission system, called the Labrador-IslandLink, which runs from the Muskrat Falls site in Labrador to aconverter station just outside St. John's.

So far, the Labrador-Island Link has been cleared to carry up to450 megawatts of power, but it's rated for up to 900 megawatts,Collett said. High-power testing will determine if it can smoothlydeliver higher volumes of power to the province's grid.

An attempted round of high-power tests using 700 megawatts failedlast November, leaving about 58,000 people in the dark for up to 25minutes. The software problem behind that failure has since beenfixed, he said.

Seven hundred megawatts is a "significant amount of power,"Collett said, and high-power testing can only be done in winter,when people crank up their thermostats and put enough demand on thegrid.

If the next test fails, N.L. Hydro will need time to figure outwhy and fix the problem, he said. After that, it likely wouldn't becold enough to run new tests until the late fall.

When asked how much another delay will add to Muskrat Falls'sprice tag, N.L. Hydro spokesperson Jill Pitcher said in an emailthat the company will reassess costs after the testing.

"If there are additional costs beyond the contingency in place,this will be captured in the final rate mitigation plan," she said.

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