A week ago, parts of Texas were suffering through cold weather and prolonged power outages.
And while that state continues to recover, it got us wondering: Could that kind of thing happen in Alaska?
It turns out, Alaska’s biggest grid has failed, but there are some major differences with Texas.
For one thing, Texas’ power grid is about 100 times “bigger” than Alaska’s Railbelt Grid, which is the largest in the state, said Brian Hickey, chief operating officer at Chugach Electric Association and an electrical engineer who has worked on the Railbelt Grid for more than 30 years.
Also, he said, the power generators in Texas are more driven by energy markets and profits, while Alaska’s mostly member-owned co-operative utilities are driven by the members’ values, placing a premium on reliability.
Still, there are some similarities, namely a lack of connection to other states for backup power, and Hickey said it’s an ongoing process building redundancy into Alaska’s grid and planning for problems.
Here’s a full transcript of the conversation with Brian Hickey, with minor edits for clarity:
Brian Hickey: We’ll evaluate the probability of that happening, the cost of fixing it, and compare it to what we think the outcome to the grid will be. Either mitigate those through operational contingencies or redesign and construct around them. Those things change over time, and we have to continue to be vigilant and continually keep the values that we have as a co-op, which are safety, reliability, cost and service.
Casey Grove: So could it happen here in Alaska?
BH: It could. I think we do a good job of planning. We haven’t had a major outage, knock on wood for many, many years. And so I think we do a pretty good job of it at this point in time.
CG: So I wanted to ask when you said a major power outage, what are some of those that have occurred in the past. What caused them and I guess were there changes made after that to improve the system?
BH: The last three significant blackouts are what we call them where we lost the entire grid. and it collapsed and had to be restarted from what we call ‘black start’ where there is no electricity. One occurred in 1989 and then there was an Anchorage bowl blackout in 1995. And then in ’96, and ’97, we had system-wide blackouts.
They were caused by interesting things. The ’89 blackout was a gas valve that failed at the Beluga Power Plant and shut off the whole plant. And really, at the end of the day, it was a little piece of wire about the size of a large paperclip that snapped and a design flaw that the main primary gas valve to the plant failed closed.
In ’95 Anchorage and the Mat-Su went down. We had a straight insulator, which is one of the big gray glass things that holds a wire off a pole – you see them when you’re driving down the road – that failed. That was a result of a bad set of insulators. It was a manufacturing flaw. So stepping back, for the ’89 blackout, we put in multiple gas valves and made sure that when they failed, they failed open. For the strut insulator failures, we replaced all those insulators. We found all the bad ones, we inspected every insulator.
In ’96 and ’97, we had one line out of service in both events, it was in the summer, and they were both warm summers. When the lines load up, they get hot and the wire tends to sag down to the ground and there’s design specifications around that. But in both cases, a tree had grown up near the line. The line sagged into a tree that the line relayed out and we lost the entire Beluga Power Plant, which at that time was the largest plant in the state. We upped our right-of-way clearing for transmission lines, shortened up our cycles on clearing transmission lines, and tightened up our inspection to make certain that we weren’t missing trees that we thought we’d trimmed but we’re still too close to the line.
Every time there’s an outage like that, and even smaller-scale outages, we have to be brutally honest with ourselves where our planning is failed. And where we’ve done well, and what we need to do less and what we need to do more.
CG: So when you say major, you mean really major?
BH: Yes. And prior to that, if you lived here in the 70s, those kinds of events used to occur several times a year. We started studying every one of them and figuring out why they occurred. When I first got into the business, that was one of the jobs I had was we’d studied those things and figure out why they occurred and then create a capital improvement plan to fix them. That’s sort of the process that’s gone on for years now to to get the grid as reliable as it is.
CG: Just to bring Texas back into this. We are better than Texas, right?
We are different than Texas – that’s a tough question. My evaluation – I don’t have any particular insight in any more than anyone else into what went on in Texas – but if you were to ask me what happened down there, it appears to me that they had an extreme weather event, which I don’t think that particular event would happen in Alaska, because we plan for cold weather.
BH: You know, potentially if we had a very, very hot summer, we could have some challenges. We don’t plan for 110 or 120 degrees summers. But the grid down there was faced with multiple contingencies. My understanding is that they have a lot of wind power in West Texas, much of that froze up. They have a lot of gas turbines that they use to backup the wind power when it doesn’t work. Well, the gas turbines froze up. They had a major new plant go down because the cooling water froze up. So they had a lot of contingencies in a once in a 30 or 50 year event.
If we were to have a system that was so reliable – infinitely reliable – that it could meet any and every contingency and event that could occur, the cost would be prohibitively expensive, and so you wouldn’t be able to use electricity to do the things you do. That’s one end of the spectrum that a planner looks. At the other end, if you had a very unreliable system that’s also very costly because the electricity isn’t there and the economic cost of not being able to achieve the things electricity allows you to do creates other problems. In between those two parentheses, there’s a sweet spot and that’s what the planners are trying to do both in the grid in Texas and here in Alaska. Getting that sweet spot I’d say is more of an art than it is a science. I think we probably are more resilient than that, but you know, anything can happen.