In recent years, with the increase of photovoltaic power stations on the road, there is a serious shortage of land resources for installation and construction, which restricts the further development of such power stations. At the same time, floating power stations, another branch of photovoltaic technology, came into our view.
Floating photovoltaic (FPV), also known as floating PV. It has a system setup similar to the ground installation. The difference lies in that all PV modules, inverters and other power plant facilities are fixed to the floating mounting system via an anchoring system. The floating photovoltaic power station is one of the five innovative applications of photovoltaic in the future. It will become a form of photovoltaic power station with great market potential after ground photovoltaic power station, rooftop photovoltaic power station and BIPV. It will be widely developed and applied in the world. According to a 2018 World Bank report, even under conservative assumptions, 400 GW of floating PV could be generated if only 1% of the world's potential water area was utilized.
Compared with traditional photovoltaic power stations, the floating PV system
is that the photovoltaic power generation modules are installed on floating bodies on water which causes more expensive to build, but it has several advantages. First, it does not occupy land resources. Secondly, floating photovoltaic power stations can reduce water evaporation, improve water quality and inhibit algae growth, which is beneficial to aquaculture and daily fishing. Finally, due to the cooling effect of water on PV modules and cables, floating PV power stations effectively improve power generation efficiency compared to ground FPV systems.
In 2017, a floating photovoltaic power station was built in Liulong Community, Tianji Town, Panji District, Huainan city, Anhui Province, covering a total area of 1,393 mu. The plant, which was connected to the grid in 2018, generates about 150 million kilowatt-hours of electricity a year. It is the world's largest floating photovoltaic power station.
The floating photovoltaic power station in Huai'a city, Anhui Province
Floating photovoltaic power stations can be built on a variety of water bodies, whether on natural lakes, artificial reservoirs or mining subsidence areas, sewage treatment plants, as long as there is a certain amount of water can be installed. Floating photovoltaic power stations can not only make "waste water" regeneration into a new power station carrier, but also maximize the self-cleaning ability of floating photovoltaic, by covering the water surface to reduce evaporation and inhibit the growth of microorganisms in the water to achieve water purification.
Floating photovoltaic power stations can make full use of water to solve the water cooling problem encountered by photovoltaic power stations on the road. At the same time, because there is no shelter over the water area and the light is sufficient, floating power stations are expected to improve the power generation efficiency by about 5%.
The floating power station was built in the mining subsidence area.
Since 2013, the number of independent installations has increased every year. By the end of 2019, more than 338 floating PV plants had been installed in 35 countries. Floating PV plants are increasingly being installed around the world, mainly to address land shortages and land use conflicts with the agricultural sector. According to a report by Wood Mackenzie power and renewable energy consultants, the global demand for floating PV plants will grow at an average annual rate of 22% from 2019 to 2024.
In terms of geographical distribution, the floating PV power station market is mainly concentrated in Asia, accounting for 87% of the global floating PV market. China has the highest number of aircraft installed, and South Korea, Japan, Vietnam, India, the Philippines, Indonesia and Singapore are also increasing investment, where the population density is high and land is scarce but the water is abundant. Europe, especially the Netherlands, built in seven weeks on an artificial lake near Zwolle in the Netherlands. The 27.4-megawatt floating Photovoltaic (PV) plant, which officially opened in June 2020, is the largest floating PV plant in the world outside of China. Meanwhile, Germany's first floating photovoltaic power station is under way.
Challenges of the development of floating Photovoltaic power stations
At present, the biggest challenge facing the development of floating photovoltaic power station comes from the cost of floating system and soft cost.
Photovoltaic modules and inverters are mature technologies. However, floating systems are usually more expensive than the same ground pv systems. The floating system includes floating components, mooring and anchoring systems. In the case of floating components alone, solutions can vary from vendor to vendor. In addition, unique mooring and anchoring solutions must be designed for each site based on factors such as changing water levels, extreme weather, etc. For a 5-10 MW floating PV plant in China, the cost of the floating component system is about one-third, while the cost of the installation structure in the ground plant is 8% higher.
Soft costs include labor, design and engineering, supply chain and logistics costs, which are also higher than those of ground power stations. After all, the construction on the water surface and the construction on the ground will increase many facilities and difficulties. The situation of each water surface is different, and the difficulty of design is higher. These costs can vary widely from projects to projects. The ambiguity of operational maintenance and post-installation costs can also deter developers and investors.
Despite these cost challenges, the surface PV has unique power generation advantages and resource utilization advantages that ground-based plants cannot achieve. As system costs fall, floating PV plants will be considered for maximum use in many countries.
As more floating pv projects come into operation, the industry will gain more experience in design, construction, operation and management. It makes it easier to evaluate system performance and reduce costs.