The photovoltaic industry never lacks new stories, but the floating PV (FPV) solution is the most practical type in recent years.
Its principle is not complicated: conventional photovoltaic modules are installed on a floating structure fixed on the water surface, with water below and sunlight above. Compared to large-scale construction on land, this approach of "taking land from the water" actually solves the real problem of a situation where there are too many people and too little land - building photovoltaics on abandoned water surfaces in fish ponds, coal mining subsidence areas, reservoirs, or industrial parks, without occupying farmland or affecting agricultural production. Especially against the backdrop of increasingly scarce land resources in the eastern coastal provinces, the number of registered floating photovoltaic projects has significantly accelerated since 2019.
From the perspective of technological evolution, early FPV systems are mainly used HDPE (high-density polyethylene) blow molded floats. In recent years, the material formula and structural design of HDPE floats have been significantly improved, and their UV aging resistance and load-bearing redundancy have been enhanced. At the same time, some leading manufacturers have begun to introduce flexible support design concepts into floating solar systems, optimizing the density of floating body arrangement and wind and wave resistance simultaneously. This technological iteration is one of the underlying logic's driving FPV from demonstration projects to large-scale commercial use.
Floating system design and subtle thresholds
The installation of photovoltaic panels on the water surface involves crossing more pits than imagined in the engineering process. Several core design dimensions are worth elaborating on.
Floating body arrangement is the first question. Floating bodies are not just about covering the water surface. They need to be customized according to local wind and wave conditions, water storage depth, and the owner's maintenance requirements for layout. The spacing between floating bodies should not only ensure structural stability, but also leave channels for underwater maintenance. In geological conditions such as coal mining subsidence areas, the floating body also needs to consider the problem of uneven stress caused by uneven settlement.
The installation angle and fixing method of components are equally critical. Floating PV systems cannot be deeply anchored on the foundation like ground mountings, and the fixed inclination of components depends on the structural rigidity of the floating body itself and the upper aluminum alloy or galvanized rigid beam frame. The core of wind resistance design is to maintain overall stability of the entire floating array under strong wind conditions, rather than allowing individual floating bodies to be blown apart. This requires a reliable lateral connection system between the floating bodies. It also means that the anchoring design must accurately match the local water depth, underwater geological conditions, and wind pressure parameters.
The anchoring system is a recognized technical difficulty in the industry and a core indicator for determining whether a floating photovoltaic company has real project experience. The mainstream solutions include three types: counterweight anchor blocks, pile anchors, and steel cable combination anchors. After the water depth exceeds five meters, the comprehensive economy of pile anchors is usually better. But when piling piles on muddy water bottoms, the difficulty and cost of construction will significantly increase, which is precisely where the collaboration ability between EPC and floating body suppliers is tested.
The weather resistance of HDPE float itself determines the service life of the entire system. The current industry standard warranty period is between 15 and 25 years. In actual engineering, some early projects' floating bodies may experience varying degrees of aging and cracking after seven or eight years, which is directly related to the material formula, local water temperature, and UV radiation intensity. The project party that only considers the price and does not look at the material testing report during procurement has suffered considerable losses.
Who is changing the rules?
From the development history of floating photovoltaic solutions, a noteworthy differentiation is already evident: top manufacturers are shifting from "selling products" to "selling systems", with floating bodies, anchoring, frameworks, and operational package delivery becoming mainstream. The continuous iteration of material formulation and structural design is quietly raising the entry threshold for this track.
The profit margin of HDPE floating solar system itself has become increasingly thin, and what really widens the gap is the precision of anchoring system design and the ability to provide customized solutions for different water conditions - these experiences require time and project volume accumulation, and cannot be caught up within a short period of money. This means that the concentration of the floating photovoltaic market in the next five years may be higher than it is now.
For the project party, it is essential to choose a floating photovoltaic supplier. However, the price of the floating body is only a superficial indicator. More importantly, the scientificity of the anchoring scheme, the matching degree of water types in previous projects, and the material testing report behind the warranty period are the real issues worth questioning.
The photovoltaic panels above the water surface are chasing after sunlight. What is truly competing beneath the water surface is the capability of systems engineering.
