Solar trackers and wind losses

The renewable energy sector has undergone a remarkable technological evolution, akin to the transformative progress witnessed in various industries. Each stride forward not only addresses specific needs but also introduces new challenges that require innovative solutions. A pivotal breakthrough within the sector unfolded with the introduction of solar trackers, boosting energy production by dynamically tracking the sun's position and optimizing the total solar radiation received by the modules. However, this technological leap brought forth a new challenge – the inherent limitation of slopes along the tracker's longitudinal axis, requiring substantial investments in earthworks, this often made the improvement less economically viable.

In the pursuit of optimizing CAPEX engineers responded by developing less rigid tracker structures., more adaptable to the site's orography. While these designs enhanced flexibility, they also introduced dynamic stresses and aeroelastic effects, leading to incidents where structures collapsed after intense wind events, but with speeds values below the design threshold. To counteract this vulnerability, a new generation of stow strategies emerged, incorporating new devices to reduce vibration such as advanced dampers, refining wind tunnel testing methodologies to correctly adress the overall loads and stress supported by the tracker, and strategically distributing structures based on their overall exposure to the wind loads within the photovoltaic plant layout.

The ongoing evolution of technology has necessitated a more rigorous assessment of project designs, placing a strong emphasis on demonstrating the cost-effectiveness of technological solutions. A critical element of this cost-benefit analysis is evaluating the production losses incurred due to tracker fenders being deployed when wind speeds exceed operational limits. This multifaceted issue has proven difficult to fully grasp, as project developers often raise subtle discrepancies between project strategies and supplier claims regarding wind speeds.

In response to these complexities, Vector Renewables takes center stage with our technology through a plant monitoring system that allows us to analyze the future plant performance, utilizing its skills in analyzing operational project data and making predictions by cross-referencing wind and solar databases. VR and NUO  serves as a precious tool for anticipating or approximating the percentage of production loss attributable to wind speeds exceeding supplier-designated limits. Due to the diverse nature of renewable energy projects - such as location, dominant wind direction, wind patterns, and structural specifications - the degree of production loss is significantly influenced by each projects unique characteristics.

Our recent studies have yielded insightful data, revealing, for instance, that projects located in regions with higher average wind speeds experienced a 15% greater production loss due to tracker fenders compared to projects situated in lower wind speed areas. This is not referring to the wind bands established in the Spanish standard and included in the Eurocode as a local annex, which already mark different design speeds. There are other factors (time of occurrence, predominant direction, speed, duration, etc) that are affecting the frequency in which trackers go to stow position, not addressed in the standards, which will affect the overall shortfall in production. These discoveries emphasize the vital relevance of a comprehensive grasp of project-specific variables.

Vector Renewables advocates for incorporating this in-depth study during the initial phases of a project's financial modeling, making sure potential losses are mitigated by appropriate design solutions well in advance. By recognizing and mitigating the challenges posed by high wind speeds, stakeholders can make well-informed decisions that enhance the long-term success of renewable energy projects. Incorporating data-driven insights becomes increasingly crucial in navigating the complexities of this continually evolving and dynamic landscape.