Joe Seman-Graves is city planner for Cohoes, New York. Where there are cities, there’s a need for power. But what does one do when there’s no available land for a power plant or wind farm? Seman-Graves needed a new idea. He started researching.
Seman-Graves searched for “floating solar,” not knowing what he’d find. But on his map of Cohoes, one feature stood out.
“We have this 14-acre water reservoir,” he says.
Seman-Graves determined the reservoir could host enough photovoltaic panels on its surface to power all Cohoes’ municipal buildings and streetlights. Plus, the project would save the town more than $500,000 yearly. City officials say the Cohoes floating solar project will be operational by early 2025.
Popular in Asia, floating solar arrays are catching on in the United States. They’re appealing as providers of non-polluting, water-conserving power that doesn’t require land. Harnessing the natural power of the Sun is one way humans recognize a blessing from the Creator—and put it to good use.
A study published in Nature Sustainability found using floating solar could generate ample electricity to serve thousands of cities worldwide.
Floating solar arrays operate simply: Photovoltaic panels attach to rafts. The panels act as “lids,” helping limit evaporation too—a huge benefit in drought-prone regions. Doing so could save enough water yearly to fill about 40 million Olympic-sized swimming pools!
Panels floating on water stay cooler than land panels, which lose efficiency when they get too hot. This allows the floating panels to generate more electricity.
Presently, the world’s largest floating solar array is a 320-megawatt megafarm in China. North America’s largest is a fraction of that—Canoe Brook Water Treatment’s 8.9-megawatt plant in New Jersey.
Canoe Brook produces 14 million gallons of drinking water daily. Each gallon weighs around eight pounds. Moving water from the reservoir to the treatment plant and into the area’s 84,000 homes and businesses takes lots of energy. The 16,510-panel solar array provides 95% of those energy needs.
Floating solar technology has challenges. Engineers must monitor oxygen and temperature levels to protect aquatic life. Electromagnetic fields from cables could possibly damage water environments—but there’s presently no evidence that’s happening. The biggest barrier is initial cost—despite the money-saving potential in the long run.
Utility giant Duke Energy launched a small floating solar project in Florida. “The favorite part of my job is that I get to come out here,” says Tommy O’Neal, Duke environmental specialist. He gestures toward panels on the cooling pond of a power plant and adds, “I never thought I’d be dealing with alligator issues.”
Why? Outside-the-box thinking generates solutions for challenging, real-world needs and problems.
