Amidst increasingly extreme weather events, growing energy demands and catastrophic power outages, Pittsburgh International Airport (called PIT by locals) may have the right idea for ensuring critical infrastructure energy resilience. Its microgrid provides an enviable level of energy independence that other airports may want to emulate — so long as they can guarantee their airport solar arrays won’t blind pilots.
PIT to double its solar
PIT has announced it’s doubling its solar capacity with a 4.7-megawatt expansion expected to go live in 2027. The new array, owned and operated by IMG, will sit on 12 acres of former landfill. Through a power purchase agreement, Duquesne Light will distribute the power generated.
PIT holds a unique place in the annals of airport innovation. In 2021, it became the world’s first airport to be powered entirely by a microgrid. Solar and gas-fired power generation provide 21MW.
Heathrow power outage findings
That’s small compared to London’s Heathrow Airport, which in March suffered a blackout that affected more than 270,000 journeys. But the two airports still share vulnerabilities. Following the blackout, critics called for more system redundancies. Heathrow had many, earning it a respectable – though ultimately insufficient – 2N redundancy rating.
Preliminary findings from the investigation into Heathrow’s power outage suggest systemic vulnerabilities and an electrical engineer’s error. In addition to further redundancies, early remediation suggestions include improved maintenance, enhanced emergency response plans and stronger government oversight. The investigation is ongoing.
A possible solution is for Heathrow to manage its own grid, as PIT does. While Heathrow has a 9MW power plant, it supplies less than a fifth of the energy needed to operate the entire facility. Another approach is to expand the use of alternative energy sources such as solar. Heathrow has rooftop arrays, but doesn’t publicize them much. They seem an auxiliary energy source instead of a contribution to airport energy security.
Airports are adopting solar
Solar and redundancy go hand-in-hand, which is driving more airports to install solar arrays. In the last decade, solar power at US airports has taken off, such as at:
- San Diego (Calif.) International Airport, which will soon have 9.5MW (if it doesn’t already). It’s also doubling its storage capacity with a new battery energy storage system.
- Denver (Colo.) International Airport, which, with 34MW, has the most solar capacity of any US airport.
- Chattanooga (Tenn.) Airport, the first airfield in the US powered entirely by solar, with 2.7MW.
Other US airports with solar include Austin-Bergstrom (Texas) International Airport (1.8MW), Augusta (Maine) State Airport (7.5MW), and Tampa (Fla.) International Airport (2MW).
Solar isn’t a complete solution for airport energy security, but it can be part of one. As more airports go solar, though, their challenges become better understood.
Solar glare can blind pilots
For example, 10 days after Heathrow’s blackout, Amsterdam Schiphol Airport reported reopening its Polderbaan runway. For weeks, the runway had been closed daily from 10 a.m. to noon. The sun’s reflection off a nearby solar array made it difficult in those hours for pilots and air traffic controllers to read their instruments and see airborne aircraft. The array wasn’t owned or operated by Schiphol, which complicated efforts to resolve the issue.
The Federal Aviation Administration requires that airport solar panels not cause “any visual impact.” More than a decade ago, when the FAA first created the policy, airports had to submit a solar glare analysis. As of 2021, they no longer do. Instead, airports are trusted to mitigate potential glare on their own. Solutions include reorienting panels, applying anti-glare coatings, using bifacial panels, and adding fencing and vegetation around the array. Devising an emergency glint response plan is also advised to quickly address problems when they occur.
The solar farm near Schiphol featured anti-glare-coated panels. They just didn’t work. The temporary fix ended up being Daylight Saving Time. Schiphol officials say a lasting solution will require additional measures.
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