In the ever - evolving landscape of photovoltaic (PV) technology, bifacial modules have emerged as a revolutionary advancement, offering the potential for increased power generation by harnessing sunlight from both the front and rear surfaces. However, this dual - sided energy - capturing capability brings about significant changes to the design of support structures, primarily focusing on increasing the ground clearance (to over 1 meter), minimizing rear - side shading, and optimizing purlin layout.

One of the most notable impacts of bifacial modules on support structure design is the requirement for increased ground clearance. Bifacial modules rely on reflected and diffuse light from the ground surface to generate additional power from their rear side. If the modules are placed too close to the ground, the amount of light reaching the rear surface is limited, significantly reducing the bifacial gain—the additional power output achieved due to the rear - side illumination.

By elevating the modules to a height of more than 1 meter above the ground, designers can maximize the amount of light that reaches the rear surface. This height provides sufficient space for light to be reflected from the ground, surrounding objects, or the atmosphere onto the rear of the modules. Moreover, a higher ground clearance helps in reducing the impact of ground - level obstructions such as tall grass, snow accumulation, or debris, which can otherwise block the light and decrease the rear - side power generation.

From a structural perspective, increasing the ground clearance necessitates stronger and more robust support structures. Taller mounting poles or columns need to be designed to withstand various environmental loads, including wind and snow. The foundation of these support structures must also be reinforced to ensure stability at the elevated height. Engineers often use advanced structural analysis software to calculate the appropriate dimensions and materials for the support poles and foundations, taking into account factors such as soil conditions, local wind speeds, and seismic activity.

Another crucial aspect influenced by bifacial modules is the need to minimize rear - side shading. Any object or structure that casts a shadow on the rear surface of the modules can significantly reduce their overall power output. In traditional single - sided module installations, rear - side shading may not have been a major concern, but with bifacial modules, it becomes a key design consideration.

Support structures for bifacial modules need to be designed in a way that avoids self - shading and shading from neighboring structures. This may involve adjusting the orientation and spacing of the modules. For example, modules should be oriented to minimize the shadow cast by adjacent rows, especially during peak sunlight hours. The distance between rows needs to be carefully calculated based on the height of the modules, the latitude of the installation site, and the time of year to ensure that the rear surfaces remain unobstructed by shadows.

In addition to row - to - row shading, support components themselves, such as  poles, cables, and purlins, can cause shading. Designers are now exploring innovative ways to reduce the shading impact of these components. For instance, using thinner and more streamlined purlins or placing support poles at strategic locations can help minimize the shadow area on the rear of the modules. Some advanced support structures even incorporate movable or adjustable components that can be repositioned to avoid shading throughout the day.

The purlin layout is also significantly affected by the use of bifacial modules. Purlins are horizontal structural members that support the modules on the mounting. In traditional installations, purlin layout was mainly focused on providing adequate support and load - bearing capacity for the modules. However, with bifacial modules, the purlin layout needs to be optimized to balance support requirements with minimizing rear - side shading.

A more optimized purlin layout may involve reducing the number of purlins or changing their spacing. Fewer purlins mean less surface area to cast shadows on the rear of the modules. But at the same time, the remaining purlins need to be designed to support the weight of the modules and withstand environmental loads effectively. This requires a detailed structural analysis to ensure that the reduced purlin layout does not compromise the integrity of the support structure.

Another aspect of purlin layout optimization is the shape and profile of the purlins. Using purlins with a more aerodynamic or low - profile design can further reduce the shading effect. Some manufacturers are now developing specialized purlins for bifacial module installations, which are designed to have minimal impact on rear - side light absorption while providing sufficient structural support.

In conclusion, the adoption of bifacial modules has transformed the design considerations for PV support structures. By increasing the ground clearance, minimizing rear - side shading, and optimizing the purlin layout, designers can maximize the power - generation potential of bifacial modules. While these design changes present challenges in terms of engineering and cost, the long - term benefits of increased energy output and improved system efficiency make them worthwhile investments in the growing PV industry.