N.L. Hydro extends life expectancy of Holyrood plant by another year as Muskrat delays continue

Newfoundland and Labrador Hydro confirmed it will delaythe decommissioning date of the thermal power generating station at Holyrood by at least another year in order to ensure customer reliability early on in the Muskrat Falls era.

The decision is linked to the ongoing struggle by GE Canada to perfect the computer software required to operate the high-voltage transmission line from Labrador to Newfoundland's Avalon Peninsula, and growing questions about the ability of the line known as the Labrador-Island Link, or LIL to withstand extreme weather events such as freezing rain storms.

In a letter to the province's utility regulator Friday, Hydro said it will commit to operating the half-century-old Holyrood plant until at least the spring of 2024. That's a year longer than plannedbut just the latest extension for Holyroodas the completion schedule for Muskrat Falls continues to be hit with setbacks.

The Holyrood station, rated at nearly 500 megawatts of electricity, is a key source of power for the Avalon Peninsula, home to about half the province's population.

But Holyrood relies on expensive and polluting bunker C fuel, and being able to replace those emissions with non-emitting hydro power from Labrador, and save money on fuel,was one of the key arguments for moving forward with Muskrat Falls.

Now there's a possibility that the Holyroodstation might be around much longer.

Hydro president and CEO Jennifer Williams could not provide a cost estimate for the Holyrood life extension, saying a staffing and maintenance strategy is being developed.

She said it's common for new utility infrastructure like Muskrat Fallsto encounter what she called growing pains, and said it was always the plan to keep Holyrood as a backup for two winters after Muskrat Falls was commissioned.

"So if you do have a bump in the early in-service years, on the LIL or the [generating station at Muskrat Falls], Holyrood will be there to help the reliability concerns that could cause," said Williams.

"Just because of the current schedule of the LIL software, we wanted to add on that extra year to make sure we have two full winters where we would plan for that extra level of reliability."

How much reliability can we afford?

Williams said Hydro is preparing a series of recommendations about reliability to the PUB, which are due by late summer. Among the options on the table? Maintaining Holyrood in standby mode for an indefinite period, and upgrading some vulnerable sections of the newly built LIL.

The LIL comprises some 3,200 towers, 2,300 kilometres of conductor wire, the 30-kilometre subsea cable across the Strait of Belle Isle, and is projected to cost $3.7 billion when complete.

Williams said the province has to strike the right balance between cost and reliability.

"Do we do some upgrades to what we currently have?Do we invest in actual backup, and if we do, do we back it up fully? Do weback it up partially?All of these are questions that we're going through with the regulator right now," said Williams.

A recent external report by Haldar Associates found that the LIL might not be as robust as was previously forecast, and could be more susceptible to failure during extreme weather events that are being magnified by the effects of climate change.

A reliability review has been ongoing for several years, and its urgency was intensified in January 2021, when ice build-up on conductor lines and towers in southern Labrador caused damage that took six weeks to repair and raised serious concerns about accessing remote areas of the line in winter and spring.

One of Haldar's recommendations is that the LIL be upgraded in some areas that are prone to ice buildup and high winds.

"We can make a 100 per cent reliable system and you'll never afford it," said Williams.

'We want them done'

Meanwhile, Williams said Hydro, using an interim version of GE's software,has been consistently transmitting more than 400megawatts of Muskrat power to the island and Nova Scotia in recent weeks, about half the rated output from new generating station on the Churchill River.

The software still hasproblems, however, and she said a final versionis expected from GE in the coming weeks, with testing and commissioning scheduled to be completed by May 31.

But GE has struggled for years to perfect the control and protection software for the line, with repeated deadlines having come and gone.

"GE wants to be done, and we want them done," said Williams, adding that despite the delays, there's a "normal contractor, owner relationship" between Hydro and GE.

"There's things we don't think customers would want us to compromise just yet. So we are holding pretty tight on what we expect from a delivery perspective from GE."

Williams said it's too early to give a revised cost estimate for the project, which is now pegged at $13.1 billion, or nearly $6 billion above the the original estimate.

But with all the delays, she acknowledged"there's some risk to that number."

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