In the utility-scale photovoltaic sector, repeat business is one of the clearest indicators of a project's success. A system may meet all its specifications on paper, but a supplier's true capability is tested when things get complicated, the timeline tightens, and decisions must be made before all the variables are finalized.
This was the context for the 149 MWdc Douro photovoltaic plant , located in Tarouca, in the Portuguese district of Viseu. Built by Zagope, a Portuguese multinational EPC company with experience in civil construction, founded in 1967, for the asset owner Sonnedix , the installation combined very hard granite formations, steep slopes, an accelerated construction schedule, and demanding monitoring requirements.
Its delivery went beyond simply completing a plant. It established the working method for a long-term relationship between Zagope and GameChange Energy , which was later expanded to reach 397 MWdc across five projects developed in Portugal.
A project that tested the execution model
Douro brought together in one location several of the most significant risks associated with the construction of a large-scale photovoltaic plant. The extreme hardness of the rock made conventional pole driving difficult and increased the likelihood of resorting to extensive drilling. The slopes, exceeding 15% in some areas, complicated the civil engineering design, the positioning of the poles, and the alignment of the platforms. Furthermore, manufacturing had to begin while the layout was still evolving, leaving minimal room for delays or poorly coordinated changes.
Geology, topography, and the schedule all put pressure on both CAPEX and planning. Foundation design couldn't be approached as a standard exercise. Adapting to the terrain had to preserve buildable area and module density. Engineering, production, and logistics had to proceed in parallel, while Zagope needed constant visibility over every phase of the process.
In this type of project, bankability is not solely a financial matter. It also depends on very specific factors: how much drilling will be required, how predictable the installation schedule can be, how design changes are handled, and whether the EPC contractor has reliable information when making decisions that affect the project.
Site-adapted engineering
GameChange Energy's in-house geotechnical engineering team analyzed available reports and pull-out test results to differentiate areas where standard pile driving was still feasible from those where the surface rock required pre-drilling and a concrete-stabilized base. Limiting the more intensive treatment to the areas where it was truly necessary contained the impact of geology on CAPEX without compromising foundation performance.
The MaxSpan™ fixed-structure system provided a second way to reduce costs. Its high-strength steel design allows for increased spacing between poles, and despite the wind and snow loads considered in the project, the final configuration used fewer than 215 poles per MW. Reducing the number of foundations meant less drilling, less on-site labor, and fewer potential points of disruption.
The topographic adaptation required the same level of precision. GameChange Energy provided the coordinates and elevations of more than 30,000 poles and performed over 20 leveling analyses as the civil design evolved. Articulated connections between tables, along with the tolerance of the pole supports, allowed the structure to follow the existing topography, limiting earthworks and maintaining the planned module density.
Keeping an evolving project aligned
The schedule required advancing the design and manufacturing process before the final layout was complete. As new geotechnical and construction information was incorporated, GameChange Energy coordinated with Zagope to make necessary adjustments, update configurations, and redistribute elements that had already been manufactured. This allowed production to continue while maintaining consistency with the final design.
Logistics were managed with the same approach. GameChange Energy's Production Delivery System provided the construction team, manufacturers, and carriers with a shared view of the 197 containers shipped in 22 shipments. The materials arrived on site at an average rate of five trucks per day. The goal wasn't just to transport components quickly, but to ensure everyone knew where they were and when they would arrive.
Color-coded identification, pre-assembled beams, and on-site training facilitated the subsequent assembly work. The first table completed by the installation team became the project's "Golden Row," a practical benchmark of quality for the rest of the structure. These measures reduced on-site handling and allowed for a faster pace without compromising installation standards.
Trust is built during the work
For Zagope, the value of the solution went beyond simply supplying steel. Douro demanded technical responsiveness, transparent communication, and daily coordination between civil engineering, manufacturing, logistics, and installation. In a project of this nature, any change in one discipline could quickly impact the others.
“Across several photovoltaic projects, MaxSpan™ has consistently demonstrated clear advantages in both cost efficiency and execution. Its suitability for complex mountainous terrain with steep, rocky profiles resulted in optimized CAPEX and measurable reductions in earthmoving and mechanical installation time.”
Equally noteworthy is GameChange's highly competent and agile engineering support, which boasts a deep understanding of the multiple disciplines required in utility-scale solar projects. In each case, after exhaustive comparative analyses of alternative solutions, MaxSpan™ proved to be the most suitable option for the specific conditions of each site, reinforcing our confidence in both the product and the collaboration,” stated Guilherme Rodrigues, Head of Procurement, Energy & Renewables at Zagope.
Their assessment highlights a crucial point. Long-term trust rarely depends on a single technical feature. It's built on how engineering decisions are made, how information is shared, and how problems are resolved under pressure.
From one plant to a portfolio of 397 MW
Douro was the catalyst for a broader collaboration. The relationship extended to four other Portuguese projects: Acail (28 MW), Riodades (61 MW), Sendim (120 MW), and Felgueiras (39 MW). Together with Douro, the five plants represent a total of 397 MWdc installed using the MaxSpan™ fixed structure system.
Repeat business at this scale goes beyond a mere commercial milestone. It indicates that the execution model developed for the first project offered the necessary reliability for reuse. Zagope had witnessed how GameChange Energy responded to challenging terrain, evolving design information, tight deadlines, and stringent supervision requirements. The continuation of the relationship was therefore based on direct experience gained on the construction site.
The portfolio also has a significant energy impact. The five plants are expected to generate approximately 630 GWh of clean electricity per year, enough to cover the consumption of about 125,000 homes. The emissions avoided are estimated at around 94,000 tons of CO₂ annually, an effect comparable to planting approximately 1.55 million trees.
Bankability is also decided during execution.
Douro's experience serves as a reminder that a plant's bankability begins to be built long before it becomes operational. It depends on predictable foundations, feasible designs, controlled material flows, rigorous assembly practices, and information systems that allow the EPC contractor and owners to accurately track the project's progress.
Complex sites will continue to be a part of large-scale photovoltaic development in Europe. Projects that can treat site constraints as starting points for engineering, rather than as unforeseen issues to be resolved at the end, will have an advantage. In Douro, this approach protected the plant's economics and schedule. And, above all, it generated the necessary confidence to move from a challenging project to a five-plant alliance.
Learn about the engineering, logistics, and installation decisions that made the project possible. Read and download the full Douro 149 MWdc case study here.