Pile driving in photovoltaic plants is one of the most widely used foundation systems for large-scale ground-mounted solar installations. It involves driving metal profiles directly into the ground using specialized machinery, often eliminating the need for concrete foundations.
This solution allows for reduced assembly times, optimized construction costs, and minimized impact on the land , provided the site’s geotechnical characteristics are compatible with the pile driving system. In this context, understanding the different types of ground-mounted solar structures allows for selecting the most suitable solution for each project.
For developers, engineering firms, and EPCs , choosing the right foundation system is essential to ensure the stability of the photovoltaic structure throughout its lifespan.
What is the driving of photovoltaic profiles?
The driving of photovoltaic profiles consists of inserting metal poles directly into the ground until reaching the depth defined in the structural design.
Driven profiles act as foundation elements of the solar structure and can have different geometries, such as C-type profiles, IPE, HEA or other sections specifically designed to support the loads of the installation.
Unlike a conventional concrete foundation, this system doesn’t require footings or curing time. Specialized machinery inserts the profiles using percussion, pressure, or a combination of both.
The final solution must be defined based on the characteristics of the terrain, wind and snow loads, the configuration of the structure and the requirements of the photovoltaic plant.
Discover why you should choose Magnelis steel for your profiles.
How is the driving of profiles carried out in a solar plant?
The installation process must be planned in advance to ensure that each profile is placed in the position, depth, and alignment specified in the project.
1. Geotechnical study and Pull Out Test
Before starting the pile driving, it is necessary to know the characteristics of the terrain.
The Pull Out Test allows for the evaluation of the profile’s behavior under tensile stress. Depending on the project, checks related to compression and horizontal or shear stresses can also be performed.
The results allow us to validate the foundation solution and establish parameters such as:
- Driving depth.
- Bearing capacity of the terrain.
- Profile type and geometry.
- Behavior under structural loads.
- Need to perform pre-drilling.
The driving depth should not be determined solely by productivity criteria: it must respond to the actual conditions of the ground and the structural calculation.
2. Topography and layout
Once the solution has been defined, the stakeout of the driving points is carried out .
The use of GPS systems and topographic equipment allows for the precise location of each pole and the maintenance of the distances and alignments planned in the project.
This phase is especially important in large photovoltaic parks, where small accumulated errors can later affect the assembly of the structures and modules.
3. Driving the profiles
With the points redesigned, the pole driving equipment for photovoltaic installations becomes operational .
The machine places the profile and gradually inserts it into the ground until it reaches the established level.
During this phase, aspects such as the following must be controlled:
- Verticality of the profile.
- Depth reached.
- Plant position.
- Row alignment.
- Possible profile deformations.
- Actual conditions encountered during the driving.
The speed of execution will depend mainly on the type of soil, the geometry of the profile, the machinery used and the conditions of the plot.
4. Pre-drilling in complex terrain
Not all terrains present suitable conditions for direct pile driving.
In particularly compact, rocky or limestone terrain, difficulties may arise that make pre-drilling necessary .
This technique involves first drilling a smaller diameter hole to facilitate the subsequent insertion of the profile and reduce the risk of deformations or damage during installation.
The decision to use pre-drilling should be based on the study of the terrain and the actual construction conditions.
Advantages of driving profiles for solar structures
Pile driving has become a common solution for ground-mounted photovoltaic structures , especially in large-scale projects. The Muniellos structure is a prime example.
Shorter execution time
One of its main advantages is the speed of installation. Once the ground has been prepared and the layout marked out, the machinery can perform a high number of pile driving operations per day when conditions are favorable.
This allows for the acceleration of one of the critical phases in the construction of a photovoltaic park.
Cost reduction
By avoiding certain concrete foundations, costs associated with the following can be reduced:
- Purchase of materials.
- Transport of concrete.
- Excavation.
- Formwork.
- Labour.
- Execution times.
- Waiting times associated with setting.
The actual savings will always depend on the terrain, the design, and the specific conditions of the project.
Less impact on the land
The driven profile system avoids, in certain configurations, the execution of large volumes of buried concrete.
This also facilitates the dismantling of the photovoltaic installation at the end of its useful life and can help reduce permanent alteration of the land.
Adaptation to large photovoltaic plants
The possibility of mechanizing and standardizing the process makes pile driving a particularly interesting alternative for large surface solar parks , where the number of profiles can be very high.
What types of land are suitable for photovoltaic installation?
The suitability of pile driving depends on the geotechnical characteristics of the site.
There is no single type of soil suitable for all projects. Strength, composition, presence of rock, stratigraphy, and local conditions must be studied before selecting a solution.
Therefore, before starting a project, it is advisable to combine:
Geotechnical study + field tests + Pull Out Test + structural calculation + pile driving test.
This methodology allows reducing the risk of encountering problems during execution and optimizing the foundation solution.
Direct pile driving or concrete foundation: which to choose?
The choice should not be made solely by comparing the price of both systems.
Pile driving can be particularly competitive when the ground allows for adequate penetration and speed of execution is desired. However, certain sites with rock, problematic soils, or specific geotechnical conditions may require pre-drilling or other foundation solutions.
Therefore, the correct question is not only how much each system costs, but which solution offers the best relationship between resistance, cost, execution time and terrain conditions .
To learn about other technical criteria that should be considered before selecting a solution for a solar park, you can consult our guide on how to choose a ground-mounted solar structure .
What depth should a driven photovoltaic profile be?
There is no universal depth for all solar parks.
The driving depth must be established through the structural design and the results obtained in the tests carried out on the ground.
Therefore, it must be integrated into the calculation of photovoltaic structures , considering the actions of wind, snow and the specific characteristics of the site.
Factors that may have an influence include:
- Soil type and resistance.
- Geometry and section of the profile.
- Height of the structure.
- Wind loads.
- Snow loads.
- Module configuration.
- Spacing between supports.
- Plant exposure conditions.
Therefore, increasing the driving depth does not always mean a better solution. The goal is to achieve the required load-bearing capacity through a technically and economically optimized solution.
Quality control during pile driving
Productivity should not be the only indicator of good execution.
In a photovoltaic plant, it is important to record and control the installation parameters in order to later verify that the profiles have been placed according to the project.
Appropriate control may include:
- Coordinates of each point.
- Final depth.
- Deviation from the vertical.
- Alignment.
- Incidents during driving.
- Trial results.
- Terrain characteristics.
- Installed profiles and areas of operation.
The traceability of this data facilitates quality control and allows deviations to be detected before they affect the assembly of photovoltaic structures.
Profile driving: an efficient solution for solar parks
The driving of profiles in photovoltaic plants combines speed of execution, mechanization and reduction of certain operations associated with traditional foundations.
However, its use must always be based on a technical analysis of the terrain. A proper geotechnical study, accompanied by tests such as the Pull Out Test, precise layout, and adequate construction control are key to achieving a stable and durable photovoltaic structure.
In large solar projects, the choice of foundation can have a direct impact on CAPEX, construction timeline, and site logistics . Therefore, comparing foundation solutions before starting installation is a strategic decision for developers, engineering firms, and EPC contractors.
Frequently asked questions about driving photovoltaic profiles
What is the driving of photovoltaic profiles?
It is a foundation system in which metal profiles are driven directly into the ground using specialized machinery to support the structure of a solar power plant.
What is a Pull Out Test in a photovoltaic plant?
It is a field test that allows the evaluation of the profile’s resistance to pull-out forces and helps to validate the foundation solution.
Are all soils suitable for driving profiles?
No. Feasibility depends on the geotechnical characteristics of the ground. In very hard or rocky soils, pre-drilling or other alternatives may be necessary.
What advantages does pile driving have over concrete?
It can reduce construction time, machinery requirements, and certain costs associated with concrete foundations, as well as minimizing the presence of permanent foundations in the ground.
Is pile driving suitable for large photovoltaic parks?
Yes, especially when ground conditions are favorable, because it allows the process to be mechanized and achieves high installation rates.
How is the driving depth determined?
It is determined through structural calculations and analysis of ground conditions, supported by geotechnical studies and field tests.
What happens if the ground is rocky?
Pre-drilling may be necessary to facilitate the installation of the profile and prevent damage or deformation during driving.
Alusín Solar and the upright structures
Driving profiles for ground-mounted photovoltaic structures is a quick and efficient solution for numerous solar projects, but its success depends on a correct characterization of the terrain and a controlled execution.
The combination of geotechnics, Pull Out Test, topography, structural calculation and pile driving control allows for the design of a foundation adapted to the real conditions of each photovoltaic park.
In short, a good pile driving solution isn’t simply about driving profiles into the ground: it’s about defining the right solution, verifying it through testing, and executing it precisely . At Alusín Solar, we can guide you through the entire process and be your best partner on-site for EPC solar projects. Request a technical consultation here.
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