NTPC says it's preparing to bring Taltson hydro online; addresses outages

The Northwest Territories Power Corporation is preparing to return the Taltson hydro facility northeast of Fort Smith, N.W.T., to commercial service in the coming weeks as a nearly two-year overhaul of the facility nears completion. 

The 60-year-old hydro plant has been off since May 2023 so its turbine and generator could be replaced. 

The facility was only expected to be offline for six months, but the power corporation said the work was prolonged because of the 2023 wildfires and mechanical problems. Communities in the South Slave have been powered with diesel generators in the meantime, which are facing challenges of their own. 

NTPC blamed worn out diesel generators as the reason for power outages in Fort Smith earlier this month. Fort Resolution, which is also relying on diesel generators due to the overhaul, had a 14-hour outage over the weekend. 

Shannon Scott, guest host of CBC's Trail's End, spoke to NTPC spokesperson Doug Prendergast Wednesday afternoon about Taltson's return to service and the recent outages.

This interview has been edited for length and clarity. 

What happens as a part of the testing — or, as you call it, the commissioning process – for Taltson?

Commissioning is really a series of tasks that our project team and contractors undertake before we can return Taltson to service. It involves things like inspection and testing equipment. We run different components of the hydro unit, stopping and starting them, taking measurements to check that clearances are correct, visual inspections and a number of other tasks. It's to ensure that everything looks good before we actually test it and put it back into service.

Part of this testing is going to involve some power outages. How many are you expecting in Hay River and Fort Smith?

I'll sort of explain why they're needed and then we can talk about numbers.

Once we reach a certain point in the process, a number of tests have been completed, we start doing some load testing. So what that means is we create electricity demand and see how the Taltson unit and the associated infrastructure like substations, transmission lines, etc., respond. 

We'll be starting with something we call the 25 per cent level. That just involves power to Pine Point. There are no customers impacted by that. So that would be the first step to see how things work. Then subsequently, we increase the load to 50 per cent, 75 per cent and finally 100 per cent. When we get to the 50 per cent mark, we need to have a planned outage in Fort Smith to create that electricity demand that's required to test how the unit performs. It should be relatively short, maybe up to 20 minutes or so. Then in subsequent tests, as we do 75 per cent and 100 per cent, we will also be adding some of the load from Hay River. 

Right now, it looks like there will be approximately five short outages in Fort Smith over four days and four in Hay River over three days. It's a bit of a moving target, but that's that's the current schedule.

With all of the unexpected and lengthy outages we've seen recently, what's your message to people who may have lost confidence in NTPC?

We understand it's been a challenging time, in Fort Smith and Fort Resolution in particular. We are committed to getting Taltson back online. Hydro power is very reliable. I think customers who have been in the South Slave for a period of time would recognize that Taltson is a great workhorse. Very rarely do we experience any kind of extended outages.

As you test the facility to get it ready again, what will that mean for water levels and ice safety?

In the immediate vicinity of the facility, there's really not a lot of ice. We've been keeping the inside of the facility warmed and therefore the water in the immediate vicinity is above freezing. So certainly there is the presence of some ice, but certainly not a lot in terms of water levels. There's just a section of the Taltson River system that will see a change in water levels, the area immediately downstream of the plant, because since the unit went offline in May of 2023, water has not been flowing through the plant. 

So the area downstream, there's no water going there. But the total amount of water coming down the Taltson River doesn't change. It takes a slightly different route. And I believe it's only about two or three per cent of total water that's coming down the river that goes through our plant.

When are you expecting the plant to be back up and fully operational?

At this point, it looks like we'll have completed all the necessary testing by late January or early February.

And if people want to stay up to date on planned power outages or when the facility is back up and running, what is the best way for them to do that?

The best way is definitely through our social media, particularly Facebook. We've announced that the first outage in Fort Smith will happen on Jan. 19, but we haven't provided a time. We intend to do that on Friday. We didn't want to provide a time too early. We also are aware of the fact that it's supposed to be quite cold in the community on the weekend, as well as there's a large women's hockey tournament in town. Those things are going into our planning for this initial first planned outage.