- How long can you and your neighbors stay safe without electricity?

(foreboding music) The answer depends a lot on the weather.

Extreme temperature is one of the most deadly natural hazards.

From a deep freeze as far south as Texas to a triple digit heat wave in the Pacific Northwest, 2021 was a year that might indicate what we could expect in the future.

Both the Texas and Pacific Northwest events had death tolls in the hundreds, which is tragic, but we need to wrap our minds around the potential for a hurricane Katrina level catastrophe or even worse as our electrical grid ages and weather becomes more extreme.

And according to experts, we have a long way to go.

- We have all of these assets that we've deployed over a hundred years, all of this infrastructure that we built for a climate that is no longer relevant, right, for a climate that we are routinely exceeding.

So in some ways we have to expect that failures will play out.

We need to be prepared for failures in a different way than we've been in the past.

- There've been 60% more power outages since 2015.

But to fully understand what's possible, we need to look a little further into the past.

- We look at, for example, the 2003 Northeast blackout as a great example of a cascading failure.

You had, you know, a few downed transmission lines in Ohio that ultimately trigger a series of events that lead to most of the Northeast not having electricity for a prolonged period of time.

And we see these sort of failures play out somewhat frequently during extreme events.

- [Maiya] And according to experts, there's plenty we can do to prepare, but we have a long way to go.

During extremes, especially with temperature, loss of power is deadly.

But calculating deaths from temperature events is difficult because most are caused by existing medical conditions made more deadly by temperature.

During the Northeast blackout, it was hot, but it wasn't extreme.

Still nearly a hundred additional deaths were reported.

The Texas power failure was far smaller, but it was extremely cold.

700 deaths were reported by Buzzfeed.

During the Northwest heat wave, blackouts for short and local, but the New York times found 600 additional deaths.

- The risk of large-scale blackouts and brownouts is pretty significant because we use electricity as sort of the backbone for our lifelines, for our lifeline services.

Of course, electricity is needed for air conditioning during the extreme heat events.

It's needed in hospitals.

Electricity is needed for pumping water.

- [Maiya] In extreme temperatures, heating and cooling are lifelines that require lots of power and utilities have to match that demand perfectly, to the millisecond.

When demand is high, there can be brief interruptions like when you turn on the microwave and the lights dim.

But imagine that on a larger scale.

- How do you go from a small scale to a large scale black out?

You've got a power system that's being pushed to its limits.

By that I mean, you are demanding a lot of it relative to its design, right?

And you know, it's basically getting close to its capacity.

- [Maiya] To understand capacity, let's first look at how the power system meets demand with Kyri Baker.

- So the power plant generates electricity, at a certain voltage.

Then they have a transformer at the power plant that steps up the voltage for high voltage transmission.

And we want to do that because if we bump up the voltage, we lower the current and lowering the current helps lower losses.

So power is transmitted at really high voltages.

Then it's stepped down for smaller commercial and residential buildings.

We're talking supply and demand balance within sub-seconds.

It really needs to be instantaneously working all of the time.

So if that doesn't happen, if there's one failure in the system, it can cause these cascading effects where a bunch of failures start to happen.

- For example, what you might have is a scenario where thousands of houses are cranking up their AC during a heat event and the substation is having to do a lot more work, but it's a lot hotter outside than it normally is, which means there's an efficiency loss.

The substation can't work as hard as it normally does, because if it did, it would overheat.

We might get to a scenario where it can't manage that dynamic fast enough, such that it trips, it automatically shuts off.

Matter of fact, we design it to shut off.

- The problem with transformers is that they are also conductors.

If there's too much power that's being pushed through that wire, it's going to heat up and in some cases it's going to overheat and catch on fire.

So we're getting these situations where there's transformers that are getting pushed past their limits, catching on fire and in some drastic cases exploding.

- [Maiya] But electricity is still moving through the grid.

So it instantly floods other substations which could be pushed past their capacity as well.

And transformers are not the only liability.

The US has over 5 million miles of power lines.

- It's not uncommon to see with hotter temperatures, sagging of lines.

You know, a power line coming into contact with a tree where you might get effectively a short of electricity and that line has to trip off.

And you might see other substations that trip themselves off because all of a sudden, you know, they can't adjust themselves to the new conditions that are playing out.

- [Maiya] Of course, the same is true of severe winter weather if ice, snow, and trees fall on power lines.

- So this is the cascade, right?

So, one or a few go offline and then a few more might go offline and then a few more might go offline.

And the more that that happens, the larger and larger and larger of a territory that you have that is offline without power.

- The US has those three main AC grids, Western Interconnection, Eastern Interconnection, and ERCOT.

The frequency fluctuations could happen in Washington and impact California a couple seconds later.

- And if you look at history, we do actually see it play out once every so often.

The question is with climate change, you know, could that be more frequently?

- [Maiya] And it's not just heat that's getting worse because of climate change.

Hurricanes, floods, wind, ice, snow, and extreme cold could cause the next major blackout, but many experts believe extreme heat will be the most deadly because even without a blackout, we could see a spike in deaths when temperatures rise above normal.

- Remember that in Phoenix, we have currently on the order of about 150 deaths per year directly attributable to heat events and that's with functioning infrastructure.

If we were to experience a prolonged large-scale blackout in the US, it's not inconceivable to expect hundreds, if not thousands of deaths with probably 10 times more hospitalizations occurring.

- [Maiya] Numbers like that would put this kind of event among the most deadly weather disasters in US history.

But as Mike reminds us, we do have options.

- The first is do nothing.

So we call that rebound and, you know, believe it or not, we do often take that approach.

The second is robustness.

You know, robustness is armoring, strengthening, and hardening.

There's a couple other approaches that sort of pick up when you exceed what infrastructure was designed for.

- Clearly, we can't talk about temperature extremes without talking about climate change.

The more we do to decrease carbon pollution, the less frequent and dangerous extreme temperatures will be in the future.

And according to both Kyri and Mike, rethinking our electrical grid could also facilitate low carbon energy, but there is some disagreement about just how to do that.

- Yeah, there's a couple divisive topics in energy right now.

One of them is the transmission versus distribution argument.

So there are some people who believe that we should just build out transmission, build out the large-scale grids.

Other people believe we should just spend a lot of money on distributed energy resources like home batteries, bi-directional EVs, rooftop solar.

It makes sense to me that it needs to be a combination of those two.

So we need to have the redundancy of transmission, but we also need to be locally self-sufficient if something happens to the broader system.

- [Maiya] So let's take what we've learned and look ahead.

Here's one potential vision for the future of the grid.

First, imagine more transmission lines connecting areas with high potential for wind and solar generation to areas that need power.

This creates redundancy in case one or more transmission lines fail and removes a major barrier to greening the grid.

Next, imagine a smart grid with distributed electrical generation.

Electric utilities will be able to see in real time how and where electricity is being used and offer incentives for shifting electricity use to off peak hours.

Solar panels on a large number of rooftops would put generation closer to demand, decreasing the strain on transmission lines and substations, while also decreasing the loss of power over long transmission distances.

Then imagine more and more adoption of electric vehicles and bi-direction charging stations that would allow you to charge your vehicle during off-peak hours.

You would also be able to use your vehicle's battery to power your home if there is an extreme strain on the grid or an outage.

What's the most extreme power outage you've been in?

We'd love to hear about it in the comments below.

Thanks for watching.

We'll see you next time.