By Isabelle Jeng, Environmental Journalist
In Sept. 2022, Hurricane Ian became the worst tropical storm to hit Florida since 1935. The Category 4 storm ravaged the Gulf Coast and left 2.7 million people without power. Babcock Ranch, however, a Charlotte County community, emerged virtually untouched. Granted, Babcock Ranch was not nearly the hardest-hit community in Florida, but its residents still felt 100-mph winds and experienced torrential rain. They never lost power or water, though, for the entire duration of the storm.
Located 30 miles from the coast to avoid coastal storm surges, Babcock Ranch is home to approximately 5,000 residents. “Power lines to homes are all run underground, where they are shielded from high winds. Giant retaining ponds surround the development to protect houses from flooding. As a backup, streets are designed to absorb floodwaters and spare the houses.” Babcock Ranch declares that “renewable energy is a way of life,” on its community site. As the first solar-powered town in the U.S., Babcock Ranch produces more solar power than it consumes. Its resilience is attributed to the 870-acre field of 650,000 photovoltaic panels that can provide enough energy for up to 30,000 homes; with residents totaling only a fraction of that, the excess power generated “goes back into the grid and is used to power surrounding communities.”
What can we in Southern California learn from Babcock Ranch? Hurricanes are not a threat here, but can we ensure a reliable source of energy after an earthquake?
A 2020 study conducted by Dr. Luis Ceferino, an assistant professor at NYU’s Tandon School of Engineering, examines the effectiveness of distributed energy resources (DERs) in increased resilience of power systems to natural disasters. A DER is a small-scale unit of power generation such as solar panels, electric vehicles, and small, natural gas-fueled generators that operates locally and connects to a larger power grid. The study concludes that if 20% of households within a community use solar panels connected to a microgrid, energy can be sustained in the event of a natural disaster. “The more microgrids there are, the more people are likely to be within these islands of electricity,” Ceferino explains. “Within a microgrid, the more people with panels, the better.”
“The power system is vulnerable to natural hazards and events especially in the U.S.,” Ceferino says. “In 2014, there was an earthquake in Napa and 70,000 residents were left without power. That was considered a moderate event.” “Batteries and solar panels can make you independent of your [power] grid,” he adds. “If your main grid is out, you can live off the battery.” Depending upon the rate of consumption, stored power can be used for up to two or three days. That is not a long time, but it is critical in the aftermath of a natural disaster, especially for healthcare facilities with an inevitable influx of victims. In a microgrid, a household supplies power to itself. Multiple buildings or homes generate electricity that can power an entire neighborhood. In “island mode,” a house is completely independent of the main grid. If a set of panels is damaged during an earthquake, a home connected to that microgrid can disconnect and sustain itself until power is restored in the main grid. This avoids power disruption throughout entire neighborhoods.
New homes in California nowadays are built with the goal of having net-zero consumption. “Net zero,” Ceferino explains, “means on average, you should generate as much as you consume. If you have a bigger roof, there is a higher chance of achieving net zero consumption.”
We know that rooftop solar panels are vulnerable to high winds, but in California, we’re more concerned about earthquakes and Ceferino says, “We don’t know as much about the vulnerability of panels to earthquakes – that’s something we may need to continue researching; if we’re going to rely on them, they need to be properly designed and implemented.”