Floating Solar Panels are Trending: Researchers Examined Their Impact on Ecosystems

Floating photovoltaic (FPV) systems appear to be a promising solution in the field of clean energy production, offering numerous benefits. However, a new study published in the professional journal Limnologica suggests that the environmental impacts of water-mounted photovoltaic cells are diverse and vary from one reservoir to another.

Researchers from Oregon State University and the United States Geological Survey modeled the impact of floating solar systems on eleven reservoirs across six U.S. states. Their simulations showed that these solar systems cool surface water, alter water temperatures at various depths, and can be associated with increased habitat variability and improved conditions for aquatic species.

In this article, you will read:

• The advantages of solar installations on water bodies.

• Their potential negative impacts.

• Which factors must be considered when evaluating the impact on reservoirs.

Numerous Benefits, Many Questions

On a global scale, floating photovoltaic systems are gaining popularity as a solution with high potential for utility-scale renewable energy production while simultaneously preserving agricultural land.

The technology offers several advantages, such as the cooling effect of water, which can increase panel efficiency by 5% to 15%. Furthermore, these systems can be integrated into existing water management and energy transmission infrastructure.

By covering the water surface, the panels also reduce evaporation, which can be highly beneficial for regions with warmer and drier climates. The technology can be specifically advantageous for dams, where preventing evaporation helps maintain stable water levels.

However, alongside the expansion of floating solar installations, questions regarding their potential negative impacts on aquatic ecosystems are being raised. Critical voices point to unclear side effects that have not yet received sufficient scientific attention, despite the fact that photovoltaic systems demonstrably alter key physical factors affecting water bodies, such as solar radiation and wind-driven water mixing.

Five Key Factors Studied

Most knowledge regarding the impact of floating photovoltaics on nature comes from indirect empirical observations and one-dimensional mechanistic models. These are generally based on comparing environmental conditions directly under the installations with adjacent uncovered areas, which often fails to capture the broader impacts at the whole-reservoir level.

Consequently, American scientists decided to develop a complementary method that simulates the physical, chemical, and biological processes governing reservoir dynamics. Using advanced modeling techniques, they assessed the impacts of floating solar panels on reservoirs as integrated systems.

The study focused on eleven reservoirs in Oregon, Ohio, Washington, Idaho, Tennessee, and Arkansas. Experts analyzed these across different seasons, focusing on five factors:

1. Surface and discharge water temperature.

2. Thermocline depth (where sudden temperature changes occur).

3. Water column stability.

4. Dissolved oxygen concentration.

5. Potential habitat availability for warm-water and cold-water fish species.

These factors were analyzed for the winter (January–February) and summer (July–August) periods. Overall, this represents the first study in the field of floating solar panels to target multiple reservoirs simultaneously while systematically evaluating impacts across various climatic zones and landscapes.

Findings: Positives and Negatives

Based on the collected data, researchers determined that greater coverage of solar panels led to increased cooling of the water surface. Additionally, photovoltaics visibly altered thermal stratification patterns.

A primary conclusion of the research was that changes in temperature and oxygen dynamics due to solar panel installation can affect habitat availability for both warm-water and cold-water fish species. For instance, cooler water temperatures in summer are generally beneficial for cold-water species, an effect most pronounced when surface coverage exceeds 50%.

However, researchers also observed that the extent of documented changes and environmental impacts varied across individual dams. This suggests that a local context is essential for a reliable environmental impact assessment of floating panels.

This is particularly true for large-scale photovoltaic installations. While they hold great potential for mitigating global warming, they may also have undesirable effects on temperature-sensitive organisms, potentially threatening local biodiversity.

Lead author Evan Bredeweg states that the implementation of solar panels manifests differently in each reservoir based on various factors—ranging from depth and flow dynamics to the composition of fish species. Therefore, no single "universal formula" can be applied to floating photovoltaics.

Recommendations for Further Research

The authors concluded the study by emphasizing the need for continued research and long-term monitoring of reservoirs with solar installations. The goal is to definitively confirm that floating photovoltaic systems contribute to clean energy targets without compromising aquatic ecosystems.

This is especially important given historical contexts, which have shown that large-scale interventions in freshwater ecosystems (such as hydroelectric power plants) can have unpredictable and permanent consequences for nature.

According to scientists, there are approximately 67,000 water bodies worldwide suitable for photovoltaic installations with 10% surface coverage. Utilizing this capacity could generate more than 1,300 TWh of electricity annually.

The market for floating solar panels is well-established and shows constant growth, currently led by Asia. "Understanding environmental risks and the variability of ecological responses to the implementation of floating photovoltaics is crucial for informing regulatory bodies and guiding sustainable energy development," concludes Evan Bredeweg.

Source: www.energie-portal.sk