A MARTÍNEZ, HOST:
Joining us now for more on the blackouts is Jonathan Snodgrass. He's a senior research engineer at Texas A&M University, where he studies power grids and transmission systems. So Jonathan, as we just heard, officials there don't know what happened that caused this blackout. But what are the different kinds of risks that power grids face that might lead to outages?
JONATHAN SNODGRASS: Right. So the risks on the electric grid range. I mean, it can be something as small as a thunderstorm that can cause downed lines all the way up to a hurricane that can knock out, say, an entire city.
MARTÍNEZ: OK. And what about heat, too? It wasn't that hot in Seville, as far as what I saw, but heat also could tax a grid?
SNODGRASS: Right. So each electric grid is designed for a certain operating temperature. So say, for example, in California, the weather is pretty mild. And so if there's extreme cold or extreme heat kind of outside of that designed temperature operating range, that can cause problems for the electric grid. And obviously, a grid in, say, like, Wisconsin is going to be designed to operate in much more colder climate than, say, a grid in Texas. And a grid in Texas would be designed to operate in a much hotter climate than, say, a grid in New Hampshire.
MARTÍNEZ: Yeah. I live in California. We have these things called Flex Alerts - a voluntary call for electricity conservation for really hot days - sometimes. What do you suspect Spain and Portugal might be doing now as they keep restoring power to make sure that this maybe doesn't happen again?
SNODGRASS: Right. So for the restoration, I'll answer kind of the restoration process is that every utility have - has what's called a black start plan. And there's - it's a procedure that they go through if - in the event of a power outage like this. So as they're restoring power, they're making sure that the generation and the load are balanced. It's restoring a grid. People might be wondering, you know - our listeners might be wondering, why don't they just turn it back on all at once?
MARTÍNEZ: Right. I was just about to say that. Yeah.
SNODGRASS: And so it's like a seesaw. So say - imagine, you know, when you're back when you're a kid and you're on a seesaw, you know, you go up and down. But the grid is like a seesaw that's perfectly level. You know, if Sally's on one side and Deshaun's on the other, if Kyle jumps on Sally's side, then that means, like, Amir has to jump on Deshaun's side to make sure it stays balanced. And the analogy goes further in the sense that you can - you have people jumping on and off the seesaw, but you can also scooch up and down on the bar to make sure that the seesaw stays balanced.
MARTÍNEZ: Yeah.
SNODGRASS: And so if you have too much jumping on - if you have too much load coming on without the generation coming on to balance that, then the whole grid could basically wind up blacking out again.
MARTÍNEZ: So not as easy as just flipping a switch.
SNODGRASS: Absolutely, yeah. It's quite complicated, but it's fascinating. And there's a lot of policies, procedures and experts in place to make sure that the grid comes back.
But to answer your question about making sure it doesn't happen in the future, that's - it's - first of all, to remind our listeners, grid outages are incredibly rare. I mean, the fact that we're talking about this means that they don't happen very often. And the Flex Alerts are something that is very important. If a utility or an independent system operator like CAISO recognizes that there might be a shortage, they'll call for voluntary conservation. So I definitely would encourage all of our listeners to take those alerts seriously.
MARTÍNEZ: One more thing really quick - about 30 seconds. This thing hit three countries - Spain, Portugal and France. What does that tell us about how interconnected these grids are?
SNODGRASS: So there's a balance between isolation and interconnection. Yeah. Texas is its own electric grid, and there's pros and cons to that. Say, the Eastern United States has its electric grid, and it's very interconnected. There's pros and cons, I would say. But in this case, it was one of the cons.
MARTÍNEZ: All right. Jonathan Snodgrass is a senior research engineer in electrical engineering at Texas A&M University. Jonathan, thanks.
SNODGRASS: Thank you.
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