Has your electricity gone out this summer? Did it feel like it was out for a long time? You may not be imagining things: A huge data analysis by a team of Berkeley scientists gives us a glimpse at the future of our drought-addled, storm-riddled electrical system.
The analysis (PDF here) looked at 13 years' worth of data, totaling 70 per cent of customers in the US -- which the authors describe as the largest such study ever completed. They were looking for two things: Whether operational upgrades and better planning has cut down on the number of outages and the duration of those outages, as well as how "major events" have affected the grid for better or worse. What, you're probably asking, qualifies as a "major" event? The ominous phrase was actually coined by utility companies -- it refers to an outage that lasts longer than a day when the system is under abnormal "stress," like during a particularly bad storm or heat wave.
Their findings are complex, but show a few things: First, the overall duration of power outages are getting more than one per cent longer every year. Meanwhile, the frequency of outages aren't changing in general, though there is a "significant correlation" between outages and lightning, wind speed, and population density. At the same time, the duration of outages are decreased as companies upgrade to underground lines.
But the most compelling finding? What the authors call "an independent, highly statistically significant correlation" between the year and the duration of power outages. It "suggests that increases in either the number or severity of major events over time has been the principal contributor to the observed trend over time," they explain, since these numbers are correlated with above-average wind speed and precipitation.
In short, there's a link between severe weather and the length of the power outage. It seems like an obvious observation, but extreme weather events are becoming a huge liability for our infrastructure -- and unprecedented studies like this one prove that it's a problem that's not just confined to a particular state or season.