Floating photovoltaic solutions (FPV solutions) are becoming a new growth point in the global photovoltaic market. Floating power stations, from Japan's Shancang Reservoir to China's coal mining subsidence areas, from Southeast Asian lakes to European reservoirs, have attracted more and more investors due to their advantages of not occupying land resources, reducing water surface evaporation, and inhibiting algal growth. However, the particularity of the water surface environment also brings unique operational challenges - high humidity, high salinity, biological attachment, wave impact, and traditional operational methods are often inadequate. How to solve the operation and maintenance problems of floating power stations on the water surface?
What are the unique challenges faced by floating photovoltaic systems on water surfaces?
The impact of water surface environment on photovoltaic power plants is multidimensional, including physical impacts and chemical erosion.
High humidity and high salt environment: Water surface evaporation causes the air humidity to remain above 80% for a long time, and salt spray (in coastal or saline alkali areas) accelerates the corrosion of metal components. The corrosion risk of metal components such as component frames, brackets, and junction boxes is significantly higher than that of ground power stations.
Biological adhesion problem: Water surface organisms (algae, shellfish, waterfowl feces) are prone to adhere to the surface of components, forming stubborn stains. Biological attachment not only affects light transmittance, but its metabolites may also corrode the glass surface.
Waves and wind loads: Water surface waves and strong winds generate periodic loads on floating systems, causing components to experience micro vibrations, which may lead to fatigue of solder strips and accelerated aging of packaging materials in the long term.
Increased PID risk: In high humidity environments, the potential induced decay (PID) risk of components significantly increases. Water surface power stations usually use string inverters, with a large number of components connected in series, high system voltage, and more prominent PID problems.
Poor accessibility for operation and maintenance: Surface operations require specialized vessels, pose high safety risks to operation and maintenance personnel, and have significantly higher cleaning and maintenance costs than ground power stations. In severe weather (strong wind, rainstorm), surface operation is almost impossible.
From industry data, the operation and maintenance costs of floating water power stations are usually 1.5 to 2 times that of ground power stations, and the power generation loss rate is also higher than that of ground power stations. How to reduce operation and maintenance costs and improve power generation efficiency is the key to the economic viability of water surface power stations.
What is the impact on the revenue of the power station?
The special challenges of the water surface environment directly affect the power generation revenue and operation and maintenance costs of the power station.
Power generation loss: Biological attachment and dust accumulation lead to a decrease in component transmittance, and power generation loss is usually between 5% and 15%. PID issues in high humidity environments may result in an additional 5% to 10% power loss.
Rising operation and maintenance costs: Water surface cleaning requires specialized vessels and personnel, and the cost of a single cleaning is 2 to 3 times that of ground power plants. Frequent cleaning requirements make operation and maintenance costs an important expense for surface power plants.
Shortened equipment lifespan: High humidity and high salt environments accelerate equipment aging, and the actual lifespan of components, inverters, cables, and other equipment may be lower than the design value, increasing replacement and maintenance costs.
Increased insurance costs: Water surface power stations have a higher risk factor, and insurance costs are usually 20% -30% higher than ground power stations.
Taking a 100MW floating power station as an example, if the annual power generation loss is 10%, calculated at a price of 0.4 yuan/kWh, the annual loss is about 16 million yuan. If the operation and maintenance cost is 50% higher than that of ground power stations, the annual increase in expenditure will be about 3 million yuan. These implicit costs are often underestimated by investors in the early stages of the project.
How to deal with the operational challenges of surface power plants?
To address the special challenges of surface power stations, it is necessary to start from multiple dimensions such as design, equipment selection, and operation and maintenance strategies.
Industry standard solutions include: selecting anti-PID components, adopting a floating system anti-corrosion design, configuring intelligent cleaning robots, and strengthening water quality management. These solutions are effective, but the implementation cost is high and it is difficult to completely solve the problems of biological attachment and dust accumulation in high humidity environments.
The pure inorganic nano coating technology of new energy provides targeted solutions for floating power stations on water surfaces.
Super hydrophilic self-cleaning: The coating has a hydrophilic angle of 5 degrees to 10 degrees, and its super hydrophilic properties allow rainwater to quickly form a uniform water film, carrying away dust and biological attachments on the surface of the components. For surface power plants, this feature is particularly important - the water film formed by morning dew and mist on the coating surface can continuously clean the component surface.
Barrier to biological attachment: The dense film layer formed by the coating changes the physical and chemical properties of the component surface, making it difficult for algal spores and shellfish larvae to attach. Even if organic matter such as water bird feces adheres, it can be quickly washed away by rainwater.
Anti-PID synergistic effect: The superhydrophilic properties of the coating reduce the accumulation of charges on the surface of the component, which counteracts the PID formation mechanism in high humidity environments. Although it cannot cure PID, it can partially alleviate the impact of PID.
Pure inorganic water resistance: Adopting Si-O-Si pure inorganic structure, without organic components, it will not decompose or fall off due to long-term immersion or high humidity environment. The performance is stable within the 5-year warranty period, and the actual service life is longer.
Reduce maintenance frequency: The self-cleaning function of the coating significantly reduces the need for cleaning. From project experience, the cleaning frequency of water surface power plants can be reduced from 1 to 2 times per month to 1 time per quarter, reducing operation and maintenance costs by more than 60%.
How to verify the actual application effect?
The pure inorganic nano coating technology for new energy has been validated in multiple floating power station projects on water surfaces.
Testing of a water surface power station in a coal mining subsidence area: In a 50MW water surface power station in a coal mining subsidence area in East China, there was severe algae adhesion on the surface of the components, resulting in a power generation loss of about 12% before cleaning. After coating application, the adhesion of algae is significantly reduced, with an increase rate of about 10%. Owners have provided feedback that the coating effectively solves the pain point of algae adhesion, and the cleaning frequency has been reduced from twice a month to once a quarter.
Coastal mudflat power station project: In a 30MW coastal mudflat project in South China, the high salt fog environment caused serious corrosion of the component frame, and it was difficult to clean the surface of saline ash. After coating construction, the salt and dust accumulation is quickly carried away by rainwater, with an increase rate of about 12%. At the same time, the coating protects the glass surface and slows down the erosion of components by salt spray.
Fishery Photovoltaic Complementary Project: In a fishery photovoltaic complementary project in Central China, there is a large amount of fog on the water surface, and the surface of the components is kept moist for a long time, resulting in severe dust accumulation and compaction. After coating application, the water film formed by morning dew and mist continuously cleans the surface of the components, with an increase rate of about 8%. Although the absolute value is not high, considering the particularity of the complementary fishing light scene, this gain is already quite considerable.
From the comparison of data, the coating issuance rate of floating power stations on water surfaces is usually between 8% to 15%, lower than heavy pollution scenarios (15% to 21%), but higher than clean environments (5% to 8%). Considering the high operation and maintenance costs of surface power plants, the cost reduction value of coatings is equally important as their additional value.
Future Development Trends
The floating photovoltaic market on water is growing rapidly, and it is expected that the global installed capacity will exceed 100GW by 2030.
Technological Evolution Direction: Future floating power stations will place greater emphasis on "low maintenance" design. The comprehensive application of technologies such as self-cleaning coatings, anti-PID components, and anti-corrosion floating systems will significantly reduce the operation and maintenance costs of surface power plants.
Application scenario expansion: In addition to traditional reservoirs and lakes, floating photovoltaic solutions on water surfaces are expanding to more scenarios such as offshore, coal mining subsidence areas, and sewage treatment plants. The environmental challenges in these scenarios are more complex, and the demand for self-cleaning technology is more urgent.
Economic improvement: With the maturity of supporting technologies such as coatings, the cost of electricity per kilowatt hour for floating water power plants will continue to decrease. In areas with scarce land resources, the economic viability of surface photovoltaics will gradually surpass that of ground photovoltaics.
For investors of floating power stations on the water surface, choosing self-cleaning technologies that are suitable for the water surface environment is the key to ensuring project profitability. The pure inorganic nano coating technology of new energy provides a reliable operation and maintenance solution for floating power stations on water surfaces due to its super hydrophilic self-cleaning, barrier to biological attachment, and pure inorganic water resistance.
FAQ: Common questions about floating power plants and coatings on water surfaces
Q1: Will the coating fail in seawater?
A: I won't. The pure inorganic nano coating adopts Si-O-Si structure, without organic components, and will not decompose due to seawater corrosion or high salt environment. The coating forms a chemical bond with the glass surface, which is firmly bonded and has excellent water resistance. In the project of coastal mudflat and mariculture scene, the coating performance is stable, and the performance will not decline within the 5-year warranty period.
Q2: Can coatings prevent algae growth?
A: The coating changes the physical and chemical properties of the component surface, making it difficult for algal spores to adhere. Although it cannot completely prevent algae growth, it can significantly reduce the amount and speed of algae attachment. Even if organic matter such as water bird feces adheres, the superhydrophilic properties of the coating can quickly wash it away by rainwater. From the project data, the coating can reduce algae adhesion by more than 70%.
Q3: Why is the coating increase rate of surface power stations lower than that of ground power stations?
A: The issuance rate mainly depends on the degree of pollution. Although the problem of biological attachment is prominent in surface power plants, the dust pollution in the air is usually lower than that in ground power plants. Therefore, the coating increase rate of surface power plants (8% to 15%) is between heavy pollution scenarios (15% to 21%) and clean environments (5% to 8%). Although the issuance rate is not the highest, considering the high operation and maintenance costs of surface power plants, the cost reduction value of coatings is more prominent.
Q4: Will coating construction affect the floating system?
A: I won't. The coating construction is only applicable to the surface of the component glass and does not involve the structure of the floating system. Special spraying equipment is used for construction, which can be carried out in the state of component installation without dismantling or moving the components. During the construction period, the floating system will maintain normal operation without affecting the power generation of the power station.
Q5: What is the maintenance cycle for the coating of water surface power plants?
A: The warranty period is 5 years. From project experience, the actual service life of pure inorganic coatings in water environments usually exceeds 10 years. After 5 years, the decision to re apply can be made based on the results of coating performance testing. The cost of reconstruction is about 50% to 60% of the initial construction, and it can be carried out without stopping the machine, with minimal impact on the operation of the power station.
