Floating Solar Power: Benefits, Key Components, and Challenges

The electrical principles behind floating solar power are similar to those of ground-mounted and rooftop systems. The unique feature is the removable floating structure, which can be installed in underutilized bodies of water for large-scale electricity generation. This article will discuss the advantages and disadvantages of floating solar, along with other useful information.

What is Floating Solar?

Floating solar, also known as floating photovoltaic (FPV) systems, refers to solar panel arrays that are placed on the surface of water. The solar panels are securely mounted on floating platforms, which may slightly sway but do not affect the system's stable power generation. Typically, floating solar systems are installed on ponds, lakes, and reservoirs, as these locations generally experience less wind than open oceans.

Floating solar is an environmentally friendly power generation method that combines marine and renewable energy technologies. The electricity generated by these floating arrays is transmitted via underwater cables to designated power transmission towers.

Key Components of a Floating Solar System

Similar to those used in ground-mounted or rooftop systems, these panels capture sunlight and convert it into electricity. More efficient panels can be used to maximize energy output in limited space.

The floating platforms are usually made from durable, high-density materials such as HDPE (high-density polyethylene) to ensure that the solar panels remain afloat. Aluminum frames may also be added to enhance stability and provide a sturdy installation structure for the solar panels.

The anchoring system securely holds the floating platform in place, preventing it from drifting due to wind or water currents. This ensures the stability and precise positioning of the solar array. The anchoring cables can be made from synthetic fibers, steel wires, or chains, depending on the depth and nature of the water body.

The DC (direct current) electricity generated by the solar panels needs to be converted into AC (alternating current) for use in electrical systems. The inverter performs this crucial conversion, ensuring optimized power output for use by the grid or on-site facilities.

Special waterproof cables and durable connectors are used to manage the electrical connections within the system. These cables link the solar panels together and transmit the generated electricity to the inverter and grid connection point on land, ensuring safe and efficient energy transfer.

Advantages of Floating Solar

Floating solar makes excellent use of space, especially in areas where land is scarce or too expensive. Floating systems can be installed in underutilized bodies of water such as reservoirs, dams, and lakes, reducing the need to repurpose land or clear natural landscapes for solar power plants. This is a significant advantage because it allows power generation without taking up valuable land, which can be used for other purposes.

The symbiotic relationship between water and solar panels helps increase solar efficiency. The natural cooling effect of water helps keep the solar panels at a lower operating temperature, reducing overheating issues. This temperature regulation can increase the efficiency of solar panels by up to 15%, leading to higher energy output and better return on investment.

Water bodies have inherent reflective properties, which enhance the albedo effect and increase the efficiency of floating solar panels. Sunlight reflected off the water's surface adds more photons to the solar panels, increasing the amount of light that can be converted into electricity. This mutually beneficial interaction boosts total energy output, making floating solar an attractive solution for optimizing solar power generation.

Floating solar panels help reduce water evaporation, which conserves water resources. This is especially valuable in drought-prone and semi-arid regions, where the shading effect of floating panels can significantly reduce water loss. Additionally, by blocking sunlight, floating systems help control the growth of harmful algae, improving water quality.

Compared to ground-mounted solar systems, floating solar systems tend to be more cost-effective. Since there is no need to purchase land or prepare large sites, these systems can be more economical to install. Furthermore, floating solar systems near existing hydroelectric plants or water treatment facilities can save on integration and transmission infrastructure costs.

Initial studies suggest that floating solar systems have less impact on aquatic life compared to other water-based or underwater structures. The design and positioning of the floating solar panels ensure minimal disruption to aquatic habitats, promoting a positive coexistence with aquatic ecosystems.

You can start with a small floating solar system and expand it as needed. The modular nature of floating platforms makes it easy to adjust and scale the system to fit different site sizes and configurations.

Disadvantages of Floating Solar

Compared to traditional ground-mounted systems, floating solar systems, along with their platforms, anchors, and cables, are more complex and have higher upfront costs. However, some cost analyses suggest that if the efficiency improvements are factored in, the total costs over the system's lifetime could be comparable to or slightly higher than ground-based systems.

Floating solar has been operational in pilot projects for over a decade, demonstrating reliable performance. However, its long-term durability is not fully confirmed. More data is needed to understand how these systems hold up over several decades of exposure, considering factors such as weather-related wear, performance degradation over time, and ongoing maintenance impacts.

This technology is not universally applicable. Many floating solar projects are large-scale and designed to supply power to commercial or utility companies. For individuals or smaller entities in need of solar power, rooftop or ground-mounted systems are typically a more practical choice.

Currently, most floating solar plants are located in artificial water bodies, including reservoirs, wastewater storage pools, and agricultural irrigation ponds. These facilities can also be found in quarries, mining sites, dams, and coastal regions. While natural bodies of water offer opportunities for solar development, artificial reservoirs have unique advantages. These reservoirs typically come with pre-existing infrastructure and pathways, making the installation and maintenance of floating solar systems easier and more cost-efficient.

Floating Systems Deployed in Marine Environments

Floating solar applications are naturally transitioning toward marine environments. Most of the world's largest cities are located along coastlines and are currently facing strong population growth, land shortages, and challenges in meeting growing energy demands. This has led to an increased interest in marine applications for floating photovoltaic systems (FPV).

The technology suitable for freshwater environments is not directly applicable to marine settings, so it is necessary to focus on developing solutions tailored for these environments. One of the key technologies required for deploying floating systems in marine conditions is the use of composite materials to withstand wind, waves, tidal forces, and ship-induced waves. Currently, floating solar systems generally use high-density polyethylene (HDPE) pontoons, which are suitable for freshwater reservoirs and prevent contamination of drinking water. However, for seawater, materials must also consider the impact of saltwater on long-term durability.

Key Technologies for Offshore Floating Systems

Depending on the region, wave heights may vary, and wave breaking can cause the structure to bear excessive loads, increasing the costs of materials, metal frames, and anchoring cables, along with higher operational costs. As shown in the diagram, based on hydrodynamic simulations, waves of 0.3 meters in height, along with tidal currents and wind speeds, can exert an impact force of approximately 14 kN2/Hz on floating systems.

JM Solar Launches Offshore Floating System Project

Floating solar is moving towards deploying floating photovoltaic systems (FPV) in marine environments. Currently, JM Solar, in collaboration with China Shipbuilding Group's 725 Institute, is advancing the "Offshore Floating Photovoltaic Application Demonstration Project," which has entered marine pilot testing. The experience from inland floating solar projects provides a pathway for scaling up and transitioning to near shore and offshore conditions. Therefore, researching the technical feasibility and challenges of designing floating systems for marine environments is of practical significance, with FPV applications initially being tested in near shore environments.