John Metcalfe is CityLab’s Bay Area bureau chief, based in Oakland. His coverage focuses on climate change and the science of cities.
Researchers wanted to forecast potential blackouts across vast spans, not just specific cities.
Florida’s two nuclear plants shut down in anticipation of a pounding from Hurricane Irma, though their owners say there’s no danger of reactor damage. There were numerous energy interruptions as the storm barreled over the Southeast. (Millions of residents were without power as of Monday morning.) Before the storm hit, researchers wanted to know: how many people might be left sitting in the dark?
Rushing in with a prediction is this “Hurricane Irma Power Outage” forecast tool that showed, at latest check on Thursday evening, about 2.6 million customers potentially affected, many in cities like Miami and Tampa. That number could be underestimating the true energy drain from Irma, as the model only takes into account the hurricane’s present forecast and omits areas to the north, where it may still head.
The tool was created by researchers who wanted to show expected blackouts on a vast scale. “We first started working on spatially generalized models in 2010 when we saw a need for a hurricane power outage model that could be used anywhere along the U.S. coastline rather than for a single utility-service territory,” email two of its creators, Seth Guikema of the University of Michigan and Steven Quiring at Ohio State University. “Utility-specific models have an important place as well, and we continue to develop utility-specific power outage forecasting models, but spatially generalized models provide valuable information to a broad set of stakeholders.”
So far, the model—which was funded partly by the U.S. government and an anonymous, investor-owned utility in the Gulf region—has enjoyed a pretty on-point track record. “With Sandy, in aggregate the prediction looked good compared to the [Department of Energy] numbers” at the time, says Guikema.
The model takes into account blackout data from hurricanes of years past as well as current weather conditions like maximum windspeed and soil moisture. “Power outages in the distribution system are primarily caused by wind blowing trees and limbs onto power lines,” says Guikema. “Therefore, our model includes a number of different measures of wind, the type of trees, and the soil moisture conditions, which provides a measure of the stability of the soil and the likelihood of a tree being uprooted.”
One thing the model does not consider is the number of people who use solar energy. Some of the folks with solar panels might come out fine, as long as the panels aren’t blown into Georgia or the Gulf by this seriously massive storm. But some solar systems are grid-fed and still could be affected by outages. The vast majority of the state’s energy comes from natural gas, though it did rank tenth in the nation in 2014 for utility-scale, solar-energy generation.
How long might the power outages last? Well, the latest forecast from the National Hurricane Center warns that Irma is “expected to make landfall in Florida as an extremely dangerous major hurricane, and will bring life-threatening wind impacts to much of the state regardless of the exact track of the center.” A Category 4 or 5 hurricane can cause blackouts that “last for weeks to possibly months.”