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By Isabella O鈥橫alley

The Associated Press

When Joe Seaman-Graves, the city planner for the working-class town of Cohoes, New York, searched the internet for 鈥渇loating solar,鈥� he didn鈥檛 even know it was a thing.

What he did know is that his tiny town needed an affordable way to get electricity and had no extra land. But looking at a map, one feature stood out.

鈥淲e have this 14-acre water reservoir,鈥� he said.

Seaman-Graves soon found the reservoir could hold enough solar panels to power all city municipal buildings and streetlights, saving Cohoes more than $500,000 each year.

Floating solar panel systems are beginning to boom in the United States after rapid growth in Asia. They鈥檙e attractive not just for their clean power and lack of need for land, but also because they conserve water by preventing evaporation.

A study published in Nature Sustainability in March found that thousands of cities 鈥� more than 6,000 in 124 countries 鈥� could generate an amount equal to all their electricity demand using floating solar. In the process, they could save enough water each year to fill approximately 40 million Olympic-sized swimming pools.

Zhenzhong Zeng, a contributor to that study and an associate professor at the Southern University of Science and Technology in Shenzhen, China, said in the U.S., counties across Florida, Nevada and California have the potential to generate more power than they use. Of course, they would need a mix of energy to provide power all hours of the day, Zeng said.

The concept of floating solar is simple: attach panels onto rafts so they float on water instead of covering land that could be used for agriculture or buildings. The panels are sealed and聽聽that brings evaporation down to nearly zero, benefiting regions like California that repeatedly experience periods of drought. The water also keeps the panels cool, allowing them to generate more electricity than their land-mounted counterparts, which lose efficiency when they get too hot.

鈥淲e hear from our installers that they like it because it鈥檚 something different,鈥� said Chris Bartle, director of sales and marketing for floating solar company Ciel & Terre, which has built 270 projects in 30 countries. 鈥淭hey get to go out on the water as opposed to on a rooftop. We joke that you need life jackets instead of ladders,鈥� he said.

Bartle鈥檚 company has launched 28 floating solar projects in the U.S.

Limited land may have spurred some countries in Asia like Japan and Malaysia to expand floating solar. Other countries took advantage of the steep plunge in solar prices that has dramatically changed the economic picture for solar adoption globally.

A report by London-based Fairfield Market Research says the region currently accounts for 73 percent of revenue from floating solar and 鈥渟pearheads the global landscape,鈥� but predicts that policy incentives in North America and Europe will spur significant growth.

One of the biggest floating solar farms in the U.S. is the 4.8-megawatt project in Healdsburg, California, built by Ciel & Terre.

鈥淚t鈥檚 funny; I don鈥檛 think a lot of people in Healdsburg know about it,鈥� said David Hargreaves, a local real estate broker and YouTuber who lives nearby. People may not know that solar panels can be placed on water, so they don鈥檛 look out for it, he said.

The world鈥檚 largest array so far is the 320-megawatt Dezhou Dingzhuang Floating Solar Farm in Shandong, China. North America鈥檚 largest, by comparison, is a fraction of that 鈥� the 8.9-megawatt array at the Canoe Brook Water Treatment Plant in Millburn, N.J., owned by New Jersey Resources Clean Energy Ventures, which operates utility-scale commercial and residential solar systems across the Northeast.

鈥淲e鈥檙e excited to see it start gaining traction in the US,鈥� said Robert Pohlman, vice president of NJRCEV.

But high up-front costs remain a barrier. Bartle estimates floating solar costs 10 to 15 percent more than land solar initially, but owners save money in the long run. Deeper water can increase installation costs, and the technology can鈥檛 operate on fast-moving water, on the open ocean, or shorelines with large waves.

Engineers are tackling other challenges. If the solar panels cover too much of a water body鈥檚 surface, dissolved oxygen levels could change and decrease water temperature, which could harm aquatic life. Researchers are looking into whether the electromagnetic fields generated by cables could negatively influence aquatic ecosystems; however, there鈥檚 no evidence of that yet.

Duke Energy, a U.S. utility that owns some 50,000 megawatts of energy capacity, is aiming to achieve net-zero carbon emissions from electricity production by 2050. It just launched a small floating solar pilot, just shy of 1 megawatt, in Bartow, Florida.

鈥淭he favorite part of my job is that I get to come out here,鈥� said Tommy Oneal, an environmental specialist at Duke Energy, as he gestured toward new panels floating atop the cooling pond of an adjacent gas power plant. 鈥淚 see eagles, alligators, and all kinds of cool stuff 鈥� It鈥檚 fun. These issues make my job different every day. When I went to college, I never thought I鈥檇 be dealing with alligator issues.鈥�

In Cohoes, public officials are preparing for installation of their project later this year at an estimated final cost of $6.5 million. The federal government is paying almost half of that through a federal Housing and Urban Development grant. Another $750,000 is being covered by the utility National Grid. The city is also looking into New York solar incentives and Inflation Reduction Act money.

As far as Seaman-Graves knows, it鈥檚 the first municipally owned floating solar project in the country.

鈥淲e are an environmental justice community, and we see a big opportunity for low to moderate income cities to replicate what we鈥檙e doing,鈥� he said.