With the approval of the second batch of leading bases, water-based photovoltaic power stations represented by Lianghuai in Anhui Province and Jining in Shandong Province have begun to become a new model for photovoltaic power station investment enterprises to explore, among which the floating water-based photovoltaic power station model is particularly novel.
After the bidding work was launched in Lianghuai and Jining, the photovoltaic industry has continuously reported on the progress of floating surface photovoltaic power stations in China in 2016. At that time, issues such as the materials, quality and lifespan of the floating bodies attracted much attention from the industry. In the past two years, the water surface photovoltaic power station model has been gradually accepted by investment enterprises, and the construction scale has been continuously expanding. At the same time, the supply of supporting products and design and construction experience are also being improved.
From floating bodies to design, the "advanced path" of the floating water surface photovoltaic market
Among the second batch of leading runner bases, the average water depth of the two Huai Rivers in Anhui Province is about 6 meters, and in some areas, the water depth exceeds 10 meters. Coupled with the subsidence terrain caused by coal mining, floating water surface photovoltaic systems have become the best choice. However, at that time, there were only a few demonstration projects of floating surface photovoltaic power stations in China. On the one hand, there was not much experience to draw on and refer to in design and construction. On the other hand, the lifespan, quality and supply of surface photovoltaic products represented by floating bodies also needed to be improved urgently.
At present, the manufacturers of floating bodies for floating water surface photovoltaic can mainly be divided into three types: One type has transformed from manufacturers of traditional wharf products and water surface facilities; One type is the occasional change of investment gap floating on the water surface, relying on contract manufacturing and speculation as the rising trend. The last one is represented by the wholly-owned subsidiary of Sungrow Power Supply (Sungrow Floating Body Technology Co., LTD.), which has entered the floating body market through industrial extension by focusing on products and overall solutions for photovoltaic power station systems.
As a company that truly entered the floating surface photovoltaic power station market from system solutions, in 2016, Sungrow Power Supply built the world's first large-scale floating photovoltaic power station in Huainan, Anhui Province, with a total installed capacity of 40MW. It has provided valuable reference experience for the large-scale development of floating photovoltaic power stations in China from aspects such as the design and supply of floating products, scheme layout, and project design and construction, and is the pioneer of large-scale floating water surface power stations.
What is still lacking in China's floating photovoltaic power station market?
The floating photovoltaic power station built by Sungrow Power Supply
According to Xiao Fuqin, the deputy general manager of Sunshine Floating Body Technology Co., LTD. (hereinafter referred to as Sunshine Floating Body Company), "The company established a special project team as early as 2012 to conduct research on the system integration of floating photovoltaic power stations on water surfaces." Technical breakthroughs are carried out from multiple dimensions, including the design of water surface arrays, the development of floating body products, the design of anchoring systems, the development of water-specific inverters and combiner boxes, as well as power generation simulation and revenue analysis. In addition, by collaborating with suppliers, a complete supply system for floating power station equipment has been cultivated. Despite thorough preparation, when the company was planning to build its first standardized and large-capacity floating power station on the water surface in 2016, it was found that the domestic supply of floating body products was far from meeting the needs of building large-scale floating power stations, and the quality of the floating bodies could not be effectively controlled. In order to ensure the high reliability of floating power stations and also based on their broad application prospects, Sungrow Power Supply decided to establish its own floating body company. As a result, Sungrow Floating Body Technology Co., Ltd. was officially prepared for establishment at the end of 2016.
Subsequently, Sunshine Floating Body Company promptly established a research team for polymer materials and a mechanical analysis team, focusing on two core issues: the lifespan of the floating body products and the force model of the floating array. After a year of efforts, these two teams conducted systematic tests and selections on the mainstream HDPE raw materials in the market, ensuring the processability and weather resistance of the production raw materials. At the same time, a dedicated mechanical testing laboratory should be established to ensure that products can be tested and verified in a timely manner.
At present, Sunshine Floating Body Company can not only provide floating body products with a service life of 25 years, but also offer customers an overall floating power station solution including floating array layout, electrical solutions, anchoring solutions, etc.
In today's era that emphasizes refined design and reduces the cost per kilowatt-hour of photovoltaic power stations, overly redundant designs will indirectly increase the overall power generation cost of the entire power station. Dr. Li Huaxiang is a professional talent dedicated to mechanics research at Sunshine Floating Body Company. To optimize the system design and reduce the overall investment cost of the system, this mechanics doctor who has studied abroad for many years chose Sunshine Floating Body as his next main battlefield.
What is still lacking in China's floating photovoltaic power station market?
Technical key points of floating surface photovoltaic power stations
Through large-scale development, a certain amount of experience has also been accumulated in the design and construction of floating surface photovoltaic power stations. By now, the Sunshine Floating Body Company has been promoting the improvement of the market environment for floating photovoltaic power stations in China.
Insufficient supply, lack of standards, design, cost... The future of floating photovoltaic power stations is still a long way off
As a representative of the large-scale development of floating surface photovoltaic power stations in China, the 1GW Leading base in Lianghuai, Anhui Province, has always attracted much attention from the industry. However, according to photovoltaic experts' understanding, up to now, no project in the Lianghuai Leading Runner Base has completed full capacity grid connection. Among them, the typical problems in the second batch of Leading Runner projects, such as land and external lines, have led to this, and the insufficient supply of floating bodies is also one of the main reasons.
In 2017, the demand for floating bodies in China's photovoltaic market was approximately 1.5GW, but the national supply capacity was only around 300MW, among which the supply of solar floating bodies was nearly 200MW, said Xiao Fuqin. The irreconcilable contradiction between supply and demand has brought huge challenges to the smooth progress of the Lianghuai Leading Runner project. It is estimated that the national demand capacity for floating bodies in 2018 will be approximately 800MW. After the completion of resource integration by Sunshine Floating Body Company and the addition of an automated production management system, it can achieve an output of 500MW throughout the year, creating a globally leading supplier of floating bodies and solutions.
While actively enhancing the production capacity of floating bodies, optimizing floating body products and floating system solutions, Sunshine Floating Body Technology Co., Ltd. is also making rapid preparations for the layout of the Japanese, Taiwan and Southeast Asian markets. These regions have limited land resources but relatively abundant water areas, making them quite suitable for the development of floating photovoltaic power stations. In addition, Xiao Fuqin stated that in the future, floating power stations will not be limited to construction in inland reservoirs and subsidence areas with good water conditions. With the advancement of technology, floating power stations will have great potential in broader water areas such as along rivers and coasts. How to ensure the safe operation of floating power stations under extreme working conditions will be a major challenge for the industry in the future.
What is still lacking in China's floating photovoltaic power station market?
Complex installation environment
Floating bodies, as an additional cost for floating surface photovoltaic power stations, have long been criticized in the process of reducing the cost per kilowatt-hour. Xiao Fuqin stated that the Sunshine floating Body is conducting precise square array buoyancy simulation to make the buoyancy of the product more scientific, eliminate unnecessary buoyancy, and thereby achieve the goal of reducing the cost of the floating body. At the same time, the effect of water surface photovoltaic power generation on increasing power generation has also been verified. About 10% of the additional power generation can fully cover the extra cost of floating bodies. In addition, compared with pile-driven photovoltaic power stations, the construction period of floating water surface photovoltaic power stations is significantly shortened, which also indirectly reduces the investment cost of photovoltaic power generation.
In addition to the above content, how to optimize the design of floating surface photovoltaic power stations, improve the anchoring system scheme, minimize the use of redundant products and the resulting cost increase still requires continuous exploration by the industry. In addition, Xiao Fuqin also called for the prompt improvement of relevant standards for floating surface photovoltaic power stations to promote the healthy, sustainable, high-quality and quantitative development of the industry.
Floating surface photovoltaic power stations not only have unique advantages in increasing power generation, but are also highly favored because they can be combined with fishery breeding to create a "photovoltaic +" model. However, from the perspective of the industry's development trend, reducing the cost per kilowatt-hour is the ultimate goal of the industry's development. Therefore, in the development of floating water surface photovoltaic power stations, it is necessary to achieve the dual goals of high efficiency and low cost in all aspects such as design, construction, installation, and products. This process still requires continuous improvement by the industry.