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It’s 2050, and the world has met its goal of net-zero carbon emissions. Instead of coal and gas plants, our electricity is mostly generated by wind farms, solar arrays, and nuclear power plants, which can now be found all across the globe—including over the water.
Offshore clean energy
Offshore oil and natural gas extraction is much more difficult and expensive than building wells on land—it’s only done because that’s the only way to access the reservoirs (there’s no way to drink these milkshakes from the coast).
Less clear are the incentives for building wind farms, solar arrays, or nuclear reactors over the water, but they do exist, and some believe these floating systems could be vital to meeting our clean energy goals.
Where we’ve been
Where we’re going (maybe)
Offshore wind, solar, and nuclear power systems are still generating less electricity than their land-based counterparts (and far less than fossil fuel plants), but interest and investment in them is increasing as global efforts to decarbonize ramp up.
To find out why, let’s take a closer look at these offshore systems, their benefits and drawbacks, and the roles they could play in our clean energy future.
Offshore wind farms
How they work: Offshore wind turbines generate electricity the same way as their land-based counterparts: Wind blows on the blades, causing them to rotate. This spins a drive shaft that is connected to a generator, and the generator converts the kinetic energy into electrical energy.
In an offshore system, this electricity is then transported to land via cables on or buried under the seabed.
If the turbines are located near the shore, where the water is less than 200 feet deep, they may be built on a rigid foundation that extends into the ocean floor. In deeper waters, they are mounted on floating structures that are attached to anchors resting on the seabed.
Current status: Wind is currently the top offshore renewable, with a total capacity of about 72 gigawatt (GW) worldwide as of 2023 (“capacity” refers to the maximum amount of electricity a system can generate if operating full time under optimal conditions).
That’s enough offshore wind to supply 19 million average American homes with power annually and a tenfold increase over global capacity in 2013.
“You can power almost the entire United States with offshore wind on the East Coast.”
Mark Z. Jacobson
The benefits: Wind speeds are higher and more stable over the ocean than over land, which means offshore turbines are typically more efficient and consistent. They’re also scalable, with plenty of suitable locations for the structures across the globe.
“You can power almost the entire United States with offshore wind on the East Coast,” Mark Z. Jacobson, director of the Atmosphere and Energy Program at Stanford University, told Freethink.
“If you put it down in the Gulf Coast and lower East Coast, you can help reduce hurricane damage, too,” he adds, citing a 2014 study he led. “If you keep the turbines running and there are lots of turbines, you can actually extract energy from the hurricanes and reduce their wind speeds and the storm surge, so there is this dual benefit.”
The drawbacks: Offshore wind farms are more expensive and complicated to build and maintain than their onshore counterparts. This is particularly true for floating offshore wind turbines.
More research is needed to fully understand how offshore wind turbines affect the environment, too. The bases of offshore turbines, for example, can act as artificial reefs that provide homes for marine life and draw new species into an area. At the same time, this increase in biodiversity can disrupt the existing ecosystem and negatively impact commercial fish stocks.
Scientists have identified ways to minimize some known negative impacts of offshore turbines on the environment, though.
Construction projects can be timed so that they avoid disrupting whale migrations, for example, and the number of bird fatalities from collisions with turbines can be reduced by 70% if we simply paint one blade black (though Jacobson notes that “the number of bird deaths are really trivial in comparison to fossil fuel bird deaths…because fossil fuels kill birds from mining, devastating the habitats, and air pollution”).
“They’re building bigger and bigger turbines that are cheaper and cheaper.”
Mark Z. Jacobson
What’s next? China has made scaling up offshore wind a priority over the past decade. As of 2024, about half of the global capacity was in its waters, and by 2030, the nation expects to increase its offshore wind capacity from the current 39 GW to 129 GW.
Its coasts are home to the largest offshore wind turbines in the world, too.
“They’re building bigger and bigger turbines that are cheaper and cheaper because the bigger you build them, first of all, they go to higher heights, and the higher you go, the faster the wind, and you also need less overall material and fewer foundations,” says Jacobson.
“China just built a 26-megawatt offshore wind turbine,” he adds. “To put it in perspective, most onshore wind turbines are two to three megawatts, so that’s up to 13 onshore wind turbines.”
The role offshore wind will play in America’s future is less clear.
As of 2024, the U.S. had less than .2 GW of offshore wind capacity total, but at least 15 new offshore wind farms are under construction or in development. If completed on time, they’ll bring the nation’s total offshore wind capacity to 19 GW by 2030—enough for about 5 million American homes.
That’s a significant increase, but nowhere near enough to make a real dent in our fossil fuel usage, and on January 20, President Donald Trump signed a memorandum that halts the leasing of federal waters for new offshore wind projects. It also pauses approvals (of permits, leases, loans, etc.) for any in-development wind project, on- or offshore, until a comprehensive review of the projects is completed—no timeline has been given for that process.
Floating solar farms
How they work: Solar panels are made from materials that convert radiation from the sun into electricity. At floating solar farms, these panels are mounted on floating platforms on top of lakes, oceans, or other bodies of water.
The electricity the panels generate is delivered to land via cables on or buried under the seabed. To keep them in place, the platforms are built on fixed foundations, tethered to anchors, or, in some cases, attached to wind turbines to create a hybrid offshore wind/solar farm.
Current status: The total installed capacity for the world’s floating solar power systems was 5.9 GW as of 2023, with nearly every large nation home to at least some floating solar.
The majority of the capacity is in Asia, though, and in 2024, the nation connected several major floating solar systems to its grid, including the largest one in the world: CHN Energy’s 1 GW farm off the coast of China’s Dongying City.
Nearly every large nation in the world now has at least some floating solar.
The benefits: Floating solar panels can enable the use of solar power in places that might not have suitable land for traditional solar farms. The approach can also free up any land that is available for other applications, such as agriculture or conservation.
The water below floating solar panels can have a cooling effect that increases their efficiency, and the panels themselves can conserve water by preventing evaporation—this can be a major benefit for reservoirs.
The drawbacks: Floating solar farms have the potential to harm the environment—reduced sunlight could impact the growth of underwater plants, for example—but exactly how and to what extent is not yet fully understood.
Floating solar farms are also more expensive to install and maintain, especially if they’re in saltwater, which can be corrosive, or particularly far from shore, where waves can be massive, but their increased efficiency could help offset those costs.
“If you could develop 10% of what we identified, that would go a long way.”
Evan Rosenlieb
What’s next? Jacobson expects that Asia will continue to lead the world in floating solar for the foreseeable future.
“China’s consumption of electricity is so high, and their land is more constrained because their population is 1.3 billion people,” he told Freethink. “The rooftops are not necessarily strong enough in some cases, and they have more highrises and not necessarily lots of single detached homes where you can put panels.”
“In the U.S., we have so much potential for [solar on] rooftops and land,” Jacobson continues, adding that “you can have big waves and hurricanes on the East Coast that can pretty easily destroy a solar farm that’s offshore.”
The U.S. wouldn’t necessarily need to build over the ocean to extract a significant amount of clean energy from floating solar, though. A new study out of the Department of Energy’s National Renewable Energy Laboratory (NREL) found that its federal reservoirs alone could support enough solar panels to power 100 million homes a year.
“We know we’re not going to be able to develop all of this,” says Evan Rosenlieb, a geospatial scientist at NREL, “but even if you could develop 10% of what we identified, that would go a long way.”
Floating nuclear power plants
How they work: Nuclear power plants generate electricity by splitting atoms. This releases a tremendous amount of energy in the form of heat, and that heat is used to boil water. Steam from the water then spins turbine blades connected to electric generators.
Nuclear power is more consistent than solar or wind, and unlike the burning of fossil fuels, it does not generate greenhouse gas emissions, though it does create a small amount of radioactive waste that must be properly stored.
The same process happens at a floating nuclear power plant (FNPP)—the only difference is that the plant is smaller and built on a ship, barge, or other floating platform rather than on solid ground.
Current status: Russia’s Akademik Lomonosov is the only FNPP in the world. The vessel went into commercial operation in 2020 and features two “small modular reactors,” each capable of generating 35 MW of electricity.
This is far less than a traditional nuclear reactor—those average 1 GW in the U.S.—but SMRs are cheaper, more compact, and easier to build, and many energy experts believe they will play a key role in decarbonizing the grid.
“Almost any coastal country or region can benefit from this technology.”
IAEA spokesperson
The benefits: FNPPs can enable the deployment of nuclear power in places that aren’t well suited for land-based plants. A remote island, for example, might have trouble constructing one due to the equipment, labor, and other factors involved, but an FNPP could be built elsewhere in the world and then driven or towed to the destination.
“FNPPs have niche markets and can be used to provide low-carbon power for applications that continue to rely on fossil fuel and where renewables such as wind or solar alone cannot be used because of their intermittency,” a spokesperson for the International Atomic Energy Agency (IAEA) told Freethink.
“Almost any coastal country or region can benefit from this technology,” the IAEA spokesperson adds.
The drawbacks: The nuclear power industry is still working to establish regulations for SMRs, and FNPPs are even more complex, given that they can involve multiple countries and the transportation of nuclear materials and technologies through international waters.
Nations interested in building or deploying FNPPs will need to be willing to wade through those still murky regulatory waters.
“Nuclear safety and security are national responsibilities, and safety and security need to be assured during operation, transport, waste management, and decommissioning of marine-based SMRs for FNPPs,” says the IAEA spokesperson.
“This is a step forward in safely harnessing nuclear technology at sea, opening new possibilities for innovation.”
Rafael Mariano Grossi
What’s next? Despite these challenges, interest in FNPPs is increasing. China, Canada, South Korea, and several other nations are now developing the systems, and in November 2024, American nuclear power company Westinghouse announced that it was partnering with U.K. startup CORE POWER to develop an FNPP featuring its eVinci microreactor.
“With this groundbreaking agreement, we will demonstrate the viability of the eVinci technology for innovative use cases where power is needed in remote locations or in areas with land limitations,” said Jon Ball, president of eVinci Technologies at Westinghouse.
Efforts to clear up some of the regulatory uncertainty surrounding FNPPs are also ramping up.
In October 2024, the American Bureau of Shipping—a not-for-profit organization that develops standards and technical specifications for ships and marine structures—released what it says is “the industry’s first comprehensive rules for floating nuclear power plants.”
In 2025, meanwhile, the IAEA will launch the Atomic Technologies Licensed for Applications at Sea (ATLAS) project, which will establish a framework for the deployment of civilian nuclear applications at sea, including nuclear-powered ships and FNPPs.
“The @IAEAorg will coordinate, facilitate, and guide this global effort,” Rafael Mariano Grossi, Director General of the IAEA, tweeted in August 2024. “We already have in place standards and guidance for nuclear safety, security, and safeguards to support this initiative.”
“This is a step forward in safely harnessing nuclear technology at sea,” he added, “opening new possibilities for innovation.”
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