Floating Solar Power Plants
A floating solar power plant has its panels mounted on floats on the surface of a lake, reservoir or the sea.
A floating solar power plant has its panels mounted on floats on the surface of a lake, reservoir or the sea. The idea came out of land shortage, since a water surface is ready space in places with no spare ground for panels.[3] The first research plant was built in Japan in 2007 and the first commercial one in California in 2008. Global capacity had reached about 13 GW by 2022. Türkiye's first example is a 1 MW plant on the Keban reservoir, and the next large project is at the Demirköprü dam in Manisa.[1][8][10]
The First Installations
The first plant was a research installation built at Aichi in 2007 by Japan's National Institute of Advanced Industrial Science and Technology.[1] Commercial use began with a winery's arithmetic. Far Niente at Oakville, California, wanted solar power for its vineyard of just over 100 acres in the Napa Valley. Panels on land meant pulling up vines, while next to them sat an irrigation pond about 240 feet across. In May 2008 it put panels on pontoons over about 80% of the pond and set the rest on the bank beside it.[2]
The floating part came to 994 panels totalling 175 kW on 130 pontoons, within an array of 2,296 panels. The floating design saved about three-quarters of an acre of Cabernet vines, which a report at the time valued at about $150,000 in annual sales. The project cost about $4.2 million.[1][2][3]
The next step was a standard product. France's Ciel & Terre turned entirely to floating systems from 2011 and developed Hydrelio, a patented modular platform.[6] Megawatt scale arrived in Japan. The 1.2 MW Okegawa plant in Saitama opened in July 2013 according to most sources, although the company's own project page gives a different date.[1][6] Short of land, Japan had more than 60 installations by 2019, the most of any country.[3] China raised the scale in 2017 with a 40 MW, 166,000-panel plant at Huainan, on a lake formed by a collapsed coal mine.[3]
What the System Is Made Of
The panels are the same as on land. Everything beneath them differs: floats, walkways joining them, a mooring system tied to the bed or the bank, and cables. A seafarer would recognise the problems. Water levels may move by metres with the dam's operating schedule, wind loads the array like a sail, and lines and chains are always working. Scientific American reported that anchors need to last 25 years or more.[3]
Typhoon Faxai at Yamakura
Yamakura showed what that risk costs. Kyocera TCL Solar built a 13.7 MW plant covering about 44 acres of the Yamakura Dam reservoir in Chiba Prefecture. With 50,904 panels it came into service in March 2018, held by 420 anchors and 823 mooring lines.[4] In September 2019 Typhoon Faxai crossed the area with winds of about 207 km/h.
According to the review by Japan's Ministry of Economy, Trade and Industry, seven anchors in the south-central section broke. The load passed to the remaining sections, panels loosened and piled together, and the array split in three. A short circuit in the damaged electrical system started a fire that destroyed about 50 panels. Because the plant had been designed as one large floating island, a failure in one part spread through the whole. The rebuild divided the platform into smaller square sections, and the plant came back in October 2021.[4] One storm had kept it out of service for about two years.
The Large Plants
Capacity meanwhile grew quickly. Sources give 1 GW for 2018, 3 GW for 2020 and 13 GW for 2022, and there is no agreed figure after that.[1] China heads the lists, with Fuyang in Anhui at 650 MWp and Wenzhou Taihan in Zhejiang at 550 MWp, followed by Chang-Bin at Changhua in Taiwan at 440 MWp.[1] The 1,000 MW Dongying HG14 off Shandong reached full capacity in December 2025 and appears on some lists as floating, but it stands 8 kilometres offshore on 11,736 steel piles driven into the seabed.[7]
Working with a dam gives these plants a strong advantage. Cirata in West Java, a project of the state utility PLN and Masdar of the UAE, opened on 10 November 2023 at 145 MWac (192 MWp). It sits on a hydropower reservoir, and Indonesia's energy minister has said that using 20% of the reservoir could support about 1.2 GWp.[5] Solar produces by day, and the dam can hold water and run when needed. Smaller plants such as Singapore's Bedok Reservoir come from land shortage once again. India has joined more recently, with Ramagundam in Telangana listed at 145 MWp and several developers opening plants on the Omkareshwar reservoir in Madhya Pradesh in 2024 and 2025.[1][7]
Yield, Cost and Water
The yield advantage was oversold for a long time. Solar cells lose efficiency as they heat up, so water cooling raises output, but commonly quoted figures ran from 5% to 15% and in some articles up to 20%. A 2024 review found that floating systems generated 0.6% to 4.4% more energy than fixed ones.[1][3] On cost, NREL researchers put installation about 10% to 25% above land in 2023, with anchoring the main reason.[1]
The stronger case in dry climates is evaporation. Measurements in arid India found about 30% saved from the covered area. A modelling study of Lake Nasser estimated that 50% coverage could save 9.07 billion cubic metres a year, 62% of the lake's evaporation. That is a model result, and nothing of the kind has been built there.[1] The technical potential is large too. The World Bank estimated more than 4,000 GW if a tenth of 6,600 large water bodies were covered, which is best read as a ceiling.[1]
The environmental effects are less clear. Covering a surface changes the light in the water and can reduce evaporation and algal growth, but its effect on fish, birds and other wildlife is not yet known.[3] Reservoirs also serve drinking water and fisheries, so there is some risk of conflict with those uses.
Moving Offshore
The move to the sea began in 2014, when Austria's Swimsol put a 15 kWp pilot in the Maldives. In 2019 the Dutch company Oceans of Energy installed the first floating farm in open conditions in the North Sea, and it came through several winter storms.[1] Salt water means corrosion, which panels have to resist.[3] So most of the world's capacity still stands on lakes and reservoirs.
Türkiye: Keban and Demirköprü
Türkiye came to this recently. The Kuzuova floating plant, on the Keban reservoir near the village of Fatmalı in Elazığ, was announced as the country's first in March 2024. It combines 1 MW on water with 2 MW on land and is expected to produce about 1.8 million kWh a year. Its purpose is irrigation. Pumping water to fields is estimated to add about 40% to costs, and Agriculture Minister İbrahim Yumaklı said these systems can supply about half the energy needed for irrigation in the area. He also said floating systems are about 10% more efficient than land-based ones, a figure above the range in the 2024 review.[8][1]
The larger step is in Manisa. In mid 2025 the Energy Ministry proposed the Demirköprü reservoir at Salihli as the first floating site under its YEKA renewable zones scheme. The reservoir of this 69 MW hydropower plant covers just under 48 square kilometres in normal conditions.[9] A project developed by Arya Solar, PMS Dock Marine Systems and Smart Güneş Teknolojileri received its pre-licence on 23 July 2026. It will feed 35 MW to the grid from 50.25 MWp of panels, with a target of about 77.6 million kWh a year. Moorings are the main question here as well. The water level can change by more than 34 metres in a year, so the mooring layout and cable routes were designed around that. The company's schedule has site work starting in September and tests finishing on 15 April 2027, subject to permits and supply.[10] An Ember analysis of February 2024 puts Türkiye's floating potential at 80 GW.[11]
Shipping connects to all this through electricity. Green hydrogen and its derivatives need large quantities of clean power before they reach a ship's tanks, and floating plants add to that renewable energy supply.
Frequently asked questions
What is a floating solar power plant?
A floating solar power plant has its panels mounted on floats on the surface of a lake, reservoir or the sea.
Is floating solar more efficient than land-based solar?
A 2024 review put the gain in output at 0.6% to 4.4%, while installation cost about 10% to 25% more in 2023.
Does Türkiye have a floating solar plant?
The first is the 1 MW Kuzuova plant on the Keban reservoir in Elazığ. The 35 MW Demirköprü project in Manisa received its pre-licence in July 2026.
Sources
- Wikipedia. Floating Solar.
- FMLink. Vineyard Goes 100% Solar and Becomes First to Use a Floating Solar Array in Its Pond, July 2008.
- Jim Daley. Putting Solar Panels on Water Is a Great Idea, But Will It Float, Scientific American, 7 February 2019.
- OneIndia. Typhoon Tore Apart Japan's Floating Solar Plant, But Engineers Built It Back Stronger.
- PV Tech. Masdar and PLN Inaugurate 192MWp Largest Floating PV Site in Southeast Asia, 10 November 2023.
- Ciel & Terre. Company Profile and Okegawa project page; Batiweb, 2013.
- pv magazine. China Commissions World's Largest 1 GW Open-Sea Offshore Solar Project, 29 December 2025; Taiyang News; Renewable Watch, 2024.
- Ekonomist. Elazığ'da Kuruldu, Türkiye'de Bir İlk Oldu, 29 March 2024.
- Balkan Green Energy News. Turkey Selects First Hydropower Reservoir for YEKA Floating Solar Power Auction, July 2025.
- CNBC-e. Türkiye'de Bir İlk Olacak: Manisa'daki Projeye Önlisans Verildi; Haberler.com (AA), 3 August 2026.
- Ember. Hibrit Santraller ile Güneş Kapasitesi Rüzgârı Geride Bıraktı, 22 February 2024.
