In 2021, Campbell published another paper based on the same principle: If California covered 4,000 miles of its canal system, it would save 63 billion gallons of water from evaporation annually and provide half of the new capacity energetic. clean that the state must achieve. . their decarbonisation goals.
Because the United States has so many tanks — about 26,000 different sizes covering a total of 25,000 square miles — the new study suggests that because there are so many tanks in the United States, they would particularly benefit from floating power. on a large scale. If the country covered 30 percent of its basin surface with floating panels, it could generate 1,900 terawatt hours of energy, about one-fifth of the world's potential, saving 5.5 trillion liters of water a year.
China can generate 1,100 terawatt hours per year, followed by Brazil and India with 865 and 766 terawatt hours respectively. Egypt could deploy 100 square miles of floating power and generate 66 terawatt hours of electricity, saving over 200 billion gallons of water annually.
The study also found that 40 developing economies, including Zimbabwe, Myanmar and Sudan, have more fluctuating capacity than current electricity demand. (Although as they develop, the demand for skills will increase.)
An added benefit of floating voltaics is that many reservoirs are equipped with hydroelectric plants, so they already have the electrical infrastructure to transport solar energy to cities. The two energy sources complement each other well, says Zhenzhong Zeng of South China University of Science and Technology, co-author of the new paper. "The interruption of solar energy is one of the main obstacles to its development. "Hydropower, which is usually controlled, can make up for the power shortage at night when the solar power goes out," says Zeng. "solar power."
Conserving water resources will become even more important as climate change increases the number of droughts, such as the historic drought that hit western states. But even if the water level in the reservoir drops significantly and the production of hydroelectric power begins to decline, the floating power plants will continue to produce electricity. (However, more remote reservoirs without hydropower will need to connect the solar panels to a larger grid, which will increase costs.)
Floating electricity can also interact very well with microgrids, says Sika Gazancu, an energy technology and policy researcher at the National Renewable Energy Laboratory. They are disconnected from the wider grid and use solar energy to charge batteries that can, for example, power buildings at night. "If you had a large pond in a remote area, deploying floating solar systems might look like applying a solar and battery project to another remote area," says Gazancu, who was not involved in the study. . new work, but collaborated with peers. I'm looking at it.
It can also benefit small communities in other ways, Gazankou says: Installing a floating system in a local pond can save water and be cheaper than trying to connect a remote area to a larger network. big. "Network expansion is very expensive," he says.
Placing the panels over canals or bodies of water would make use of space that has already been altered by humans and would not require additional land clearing for massive solar parks. (Floating cells can also be applied to polluted bodies of water, such as industrial ponds.) "Solar energy requires about 70 times more land than a gas-fired plant of the same capacity," says environmental engineer Brandi McQueen of the University of California. California. , Merced, who wrote an article on the channel with Campbell, but was not involved in this new work. "If we want to achieve these ambitious climate goals while protecting biodiversity, we really need to look at these solutions that use the built environment."
In recent years, floating installations have evolved from small projects to large solar farms, such as Singapore's Tenge Reservoir, where the panels cover the equivalent of 45 football fields. As the systems expand, "we really need more research into what some of the potential impacts are when we think about these aquatic ecosystems," Gazancu says. For example, shade can discourage the growth of aquatic plants, and panels can create problems for native waterfowl and migratory birds that depend on water bodies for burrowing. For example, it may be useful to determine whether there is optimal spacing between panels to allow species to move freely through the water.
While these projects won't just power entire metropolitan areas, they will help diversify electricity generation by making the grid more resilient as the renewable energy revolution accelerates. "Energy is such a big problem that we won't have a cure," says Campbell. "We need floating PV and hundreds of other things to meet our energy needs."
