“A floating solar array on a pond in Orlando. Florida has thousands of lakes and ponds where floating panels could be used”. Photo: Paul Hennessy, SOPA Images, ZUMA Press in WallStreet Journal
SB 1338/HB 1411
State requirement for amendments to local land regulations to promote floating solar panels
Backgrounder: “Where to put solar panels? How about on the water?”
“Floating solar panels are still a small part of the energy mix. But they have some advantages over land-based systems.
As befits its location in the Sunshine State, Orlando International Airport looked at installing solar panels on its property to help it reduce its electricity costs. But ultimately it decided not to commit land for such a purpose.
The airport’s land is too precious to use it for solar development, says Mark Birkebak, director of engineering for the airport.
Its water, however, proved to be a different matter. In December [2020], the Orlando Airport and the city’s main power provider rolled out floating solar panels on one of several ponds on airport property. Now, almost a year in, the water-based array provides energy equal to what 14 homes would consume, and the airport earns credits for the energy it pumps back into the grid.
As an extra flourish, Mr. Birkebak says, the panels are arranged in a stylized ‘O’—the Orlando airport emblem—illuminated at night by LED lighting and visible to passengers on jets and trams.
‘You can add a little artsy-ness to this and still have a great benefit,’ Mr. Birkebak says…
The number of solar-energy installations grew 23% world-wide in 2020, according to an International Energy Agency report, and are expected to keep growing globally through 2022 as power providers continue to fulfill mandates to add renewables to their energy mix. A small but increasing portion of that growth is expected to come from water-based solar arrays.
While land-based panels are the more popular choice for solar by far, largely due to higher installation costs for water-based systems, developers and scientists increasingly agree there are situations in which water-based arrays have advantages.
Continuing to find new places to accommodate solar panels is becoming more of a challenge. In the U.S. and elsewhere, opposition has been voiced by residents in some communities where large solar arrays have been proposed—by farmers who don’t want to convert food-crop land to solar farms, and by conservationists who don’t want forests cleared for panels.”
“Mayor Buddy Dyer walks past a floating solar array at Orlando Airport after a ribbon-cutting ceremony for the installation last December.” Photo: Joe Burbank,Associated Press
“Floating solar arrays, by deploying their panels on man-made reservoirs or lakes that aren’t used for recreation, can alleviate such concerns. The state of Florida, for instance, has thousands of lakes and ponds where floating panels could be used…
In addition to overcoming land-related issues, it is also possible that water, due to its cooling effects, could make solar panels work more efficiently. A study by Brazilian scientists published by IET Renewable Power Generation found that floating arrays generate as much as 12.5% more electricity than ground or rooftop solar installations. The panels can also slow evaporation, protecting essential water sources already affected by increased demand and climate change…
Asia is expected to account for more than 80% of floating solar through 2026, Europe an estimated 7% to 10%, and the U.S. 1% to 2%…
Many of the bodies of water highlighted in the NREL study were in regions with high electricity rates and high land prices. In such areas, floating solar, despite its higher installation costs, could still be the cheaper solar option, in part by removing the need for expensive land purchases.
To be sure, water-based solar does have some disadvantages, such as higher installation costs due to the need for floats, moorings and waterproof electrical components. Such items tend to cancel out any savings that water-based arrays might offer in terms of requiring no earthmoving or vegetation removal, says Evan Riley, chief executive and founder of White Pine Renewables, a company that has installed both floating solar and land-based systems.
Because of its higher installation costs, developers of floating solar tend to target reservoirs that already host hydropower and have connections to the grid in place.
‘For commercial or industrial-size floating solar, access to transmission can easily make or break a project,’ says NREL’s Mr. Macknick.
Another disadvantage for floating panels is their inability—so far—to track the sun’s movement. In the U.S., most ground-mounted solar panels are installed on trackers that allow the panels to turn and absorb the sun’s rays at the most favorable angle throughout the day. This isn’t possible yet for floating solar. So, despite having better efficiency, floating solar panels can’t produce as much energy as trackers allow.
‘We either need a technological innovation so that the panels can track the sun while floating,’ Mr. Riley says, or floating solar will have to ‘take off in markets where it doesn’t have to compete with a ground-mounted tracker.’…
‘We just now have the price of solar panels low enough that the business case is really getting to pick up.’ Mr. Lehner says. ‘It’s just a matter of time that floating solar will conquer many of these markets.'”
— Jackie Snow, WallStreet Journal