Adapt to the Solar Landscape: Terrain-Following Trackers

By August Christensen, PE, Kevin Andersen, PE, and Brett Vanderwiel 

In the rapidly evolving world of solar energy, the introduction of terrain-following trackers marks a significant leap forward. This innovative technology is revolutionizing the way we approach solar installations, particularly in challenging terrain. By allowing solar arrays to adapt to the natural contours of the land, these systems minimize environmental disruption, reduce construction costs, and enhance the efficiency of solar farms. 

Terrain-Following Tracker Benefits 

Traditional single-axis tracker systems are typically linear, potentially requiring extensive land grading to create a flat surface along the racks for ease of installation and creating a more uniform reveal height to simplify foundation sizes/lengths. This may not only increase the project's environmental impact footprint but could also escalate construction costs due to the extensive earth-moving required. In contrast, terrain-following tracking systems maintain a north-to-south alignment and introduce a critical innovation: the ability to articulate or bend at certain locations along the rack, adapting the profile of the rack to the terrain's natural undulations. 

This capability significantly reduces the amount of land disturbance, especially on steep or irregular sites. In most cases, this racking method reduces grading by 40-60%. In some cases, it can reduce it even further. For example, our team assisted a client on a utility-scale solar project that contained significant ditch and topography concerns. The design approach utilized a terrain-tracking solution to reduce the project’s grading from over 1,000,000 cubic yards of dirt to be moved to less than 300,000 cubic yards. By following the terrain undulations, these systems can be installed with minimal disturbance to the land, reducing the risk of erosion and preserving the natural ecosystem. It may also reduce the rack profile height, providing benefits to the size/length of the foundations needed. The flexibility offered by terrain-following trackers makes previously unusable sites viable for solar development, expanding the potential for solar energy generation to more diverse geographical areas. 

This model shows the differences between traditional and All Terrain Trackers®, provided by solar racking manufacturer Nevados. 

Innovative Tools in Design and Construction 

We have been at the forefront of this industry evolution since the introduction of terrain-following trackers. Our long-standing engagement with these technologies has allowed us to build a robust infrastructure of support services tailored specifically to the complexities of modern solar projects.  

At the heart of our design approach for solar projects is a suite of innovative tools created in-house to optimize the integration of both traditional and terrain-following racking systems. These tools allow for a dynamic and responsive design process, adapting to each site's unique challenges. Using our internal tools, we can simulate various scenarios, comparing the effectiveness and environmental impact of different racking configurations. This not only ensures optimal efficiency but also provides our clients with tailored solutions to meet their specific needs. 

One key feature of our technology is the ability to alter the rack’s foundation point elevations post-grading during active construction. This flexibility is crucial for required field changes without the need for comprehensive redesigns, additional ground disturbance, or the order for new foundations. Our tools also enable a detailed analysis of grading quantities and foundation steel usage. By integrating these factors into a comprehensive design platform, we can offer a holistic view of project feasibility and efficiency, empowering our clients to make informed decisions and optimize the project holistically. 

We have refined our tools and processes, ensuring we are ahead of industry trends and off-the-shelf tools to continue offering state-of-the-art solutions. This deep-rooted experience enhances our capability to handle current diverse project demands and to tackle the challenges of tomorrow’s energy landscape. 

Enhanced Efficiency and Sustainability 

The benefits of terrain-following tracking systems extend beyond reducing traditional civil quantities and the associated cost savings. These systems also contribute to the overall environmental sustainability and efficiency of solar projects.  

A properly stabilized construction site significantly decreases the project’s risk of major erosion. Unstabilized, disturbed soil is a major contributor to erosion at construction sites. By minimizing the need for extensive grading typically required in conventional projects, these tracking systems reduce the overall area of disturbed soil. Consequently, there is less need for materials and labor to stabilize these areas, enhancing the likelihood of meeting environmental compliance standards and timely permit closure. 

Additionally, the versatility of terrain-following trackers allows for the installation of solar arrays on diverse topographies, optimizing land utilization and potentially increasing energy production. This capability is increasingly valuable as flat, easily accessible land becomes more limited, and the solar industry looks to expand into varied and challenging environments. 

Leading the Charge in Solar Innovation 

As we continue to push the boundaries of solar technology, terrain-following trackers for solar stand out as a beacon of innovation and efficiency. By embracing these systems, we are not only optimizing the economic and environmental aspects of solar projects but also paving the way for a more sustainable and resilient energy future. Contact our team to learn more about our commitment to innovation and enhancing the design and implementation of solar racking systems. 

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About the Authors 

August Christensen, PE, Principal Solar Engineer, has been with Westwood for over 20 years, 17 of which have been in renewable energy. As Principal within the Renewables Division, August provides technical direction and oversight to the solar civil engineering teams in all offices. 

Kevin Andersen, PE, Site Design Engineering Manager, has been with Westwood for over seven years, coming from a transportation engineering background. Kevin serves the renewables division and manages the site design (civil) engineering team in Madison. Kevin also performs civil engineering project leadership and quality control for solar, wind, and battery storage projects. 

Brett Vanderwiel, Site Design Engineering Manager, has been with Westwood for over six years. He has been working in Solar for close to 10 years, from the field to design and management. Brett is responsible for managing the solar site design team in the Minnetonka office and leading the civil engineering scope on a variety of renewables projects. His expertise spans all stages of design from early engineering development through construction, including site layouts, site and facility grading, pile elevations, erosion control design, stormwater permitting, and coordination with contractors and owners during construction.