Efficient Ground-Mounted Photovoltaic Systems: Tips & Costs Overview
Why are ground-mounted photovoltaic systems crucial? These systems ensure optimal orientation and stability of your solar modules while increasing energy yields. This article provides you with a comprehensive overview of various mounting systems, their advantages, costs, and practical installation tips.
Key Takeaways
Ground-mounted photovoltaic systems offer flexible design and can be installed either south-oriented or east/west oriented for higher yields during peripheral hours of the day.
There are fixed and tracking mounting systems, with tracking systems potentially increasing energy yield significantly, though requiring higher initial investments.
Installation costs for photovoltaic systems vary depending on size and system configuration, while government funding opportunities and subsidized loans offer support.
Ground-Mounted Photovoltaic Systems: Fundamentals
Ground-mounted photovoltaic systems offer large areas that enable better load-bearing capacity and ensure easy expansion and maintenance. Unlike roof-mounted PV systems, these installations are less restricted by roof structure and available space. This allows for more flexible design and optimal orientation of PV modules to best utilize solar energy.
Ground-mounted photovoltaic systems are increasingly being oriented east/west rather than directly south. While this results in slightly reduced power production, the yield is higher in the early morning hours and evening hours compared to southern orientation. Due to increasing solar power production, there tends to be a surplus of electricity at midday anyway, leading to very low (or even negative) electricity prices on the power exchange. Prices during peripheral hours are therefore significantly higher, thus increasing the overall financial return of the system, even if slightly less power is produced in absolute terms.
Photovoltaic systems can also help enhance ecological areas and increase biodiversity when properly maintained. For example, ground-mounted PV systems can be designed to provide habitats for various plant and animal species. This can be achieved through:
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Designing ground-mounted PV systems to provide habitats for various plant and animal species
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Planting native vegetation
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Creating habitats for birds and insects
Another aspect that can increase the efficiency of ground-mounted photovoltaic systems is the use of tracking systems. These allow the solar modules to follow the sun's movement and significantly increase overall energy yield. Through the use of such systems, the energy yield of a photovoltaic system can be up to 30% higher depending on location and orientation.
Types of Mounting Systems for Ground Installations
There are various mounting systems for ground-mounted photovoltaic installations that can be selected based on specific requirements and conditions. These systems are designed to securely fasten the PV modules and ensure optimal orientation toward the sun.
Fundamentally, mounting systems can be divided into two main categories: fixed mounting systems and tracking systems. Below, both systems are explained in detail to give you a comprehensive overview of their advantages and disadvantages.
Fixed Mounting Systems
Fixed mounting systems are the most common type of mounting for ground-mounted photovoltaic installations. These systems offer high stability and durability, making them ideal for long-term installations. Another advantage of these systems is that they are relatively easy to install and have low maintenance requirements.
A typical fixed mounting system consists of a frame that holds the PV modules at a fixed angle to the sun. The maximum overhang length of the PV rail is 40 centimeters, contributing to the system's stability. This type of mounting system can accommodate up to 18 modules, contributing to the system's efficiency and longevity.
These systems are particularly advantageous in snowy areas as they hold the modules at a stable angle to withstand snow loads. In windy regions, they also offer high stability and security through their robust construction.
Tracking Systems
Tracking systems are an innovative solution that allows PV modules to follow the sun's movement. These systems can maximize energy yield by always keeping the modules at an optimal angle to the sun. This can significantly increase the total energy yield of a photovoltaic system.
The adjustability of tracking systems according to the sun's position offers a decisive advantage over fixed systems. These systems are particularly effective in regions with high solar radiation as they optimally utilize solar energy throughout the day.
Despite their higher acquisition costs, tracking systems can be a worthwhile investment in the long term as they significantly increase energy production and thus improve the system's profitability.
Materials for Mounting Systems
The choice of material for the mounting system is crucial for the longevity and stability of the photovoltaic system. Aluminum is a commonly used material due to its lightness and corrosion resistance. It is particularly advantageous in humid and salty environments as it is less susceptible to corrosion.
Steel, on the other hand, offers high stability and is often used in windy areas. Galvanized steel is another popular choice as it provides additional rust protection and extends the structure's lifespan.
Fixed mounting systems made of aluminum or galvanized steel offer high stability and are often long-lasting, making them ideal for long-term installations. These materials help ensure that the mounting systems can withstand various environmental conditions.
Requirements for Mounting Systems
Regardless of the material, the mounting structure should be designed to withstand regional requirements for wind and snow loads (e.g., 0.71 kN/m² and 2.17 kN/m²). These loads must be considered during the construction and installation of the systems to ensure safety and stability.
Different mounting systems are suitable for various ground conditions. The mounting structure should be made of stable metal to meet load and stability requirements. Improper mounting can lead to significant damage, which is why the mounting of PV modules must be carefully planned and executed.
The orientation and inclination of the mounting structure should be adapted to the prevailing wind direction to minimize loads. The number of required roof hooks for the substructure also depends on regional snow and wind loads. The roof plays a crucial role in this.
Additionally, the systems must be designed to meet fire protection requirements. Various mounting systems can be used to securely and stably fix the PV modules.
Installation of Mounting Systems
The installation of ground-mounted photovoltaic systems typically takes between 4 to 8 weeks, depending on size. This work is carried out by professional personnel, including solar installation companies, electrical installers, and specialized contractors. It is important that a professional connects and commissions the PV system, as certain documentation requirements must be met for commissioning.
It is advisable to seek professional advice, as they can support throughout the entire process and adapt the system to local conditions. The PV modules are mounted on trapezoidal sheets. Special rails are used for this, which are attached to the raised areas.
A simple screw foundation is often used for the photovoltaic frame, which facilitates and accelerates installation.
Costs of Mounting Systems
The static calculation and inspection of the mounting systems are included in the total costs of the PV system and play an important role in the cost structure.
The average costs for installing a PV system with a capacity of 5 to 10 MWp amount to 550 euros per kWp, plus planning costs of approximately 100 euros per kWp. When planning the total costs, annual operating costs of 1-2% of the purchase price should also be considered. These are rough guidelines that can vary significantly depending on market conditions (e.g., material prices, system size, location, soil assessment, etc.).
Funding Opportunities and Financing
The KfW Bank offers loans for the installation of PV systems and battery storage through Program 270. These loans can cover up to 100% of the eligible costs, with a maximum amount of 150 million euros. Natural persons and companies can apply for funding.
The installation of the PV system must be carried out by a qualified professional company to be eligible for funding. It is important that the funding application is submitted before beginning the PV system installation. Combining the funding with other state grants for similar projects is permitted.
Maintenance and Care of Mounting Systems
Fixed mounting systems are designed to provide a stable angle of inclination and are easy to install and low-maintenance. The choice of material for mounting systems influences the longevity and maintenance requirements of the photovoltaic system.
Summary
In summary, ground-mounted photovoltaic systems offer an excellent opportunity to generate sustainable energy while achieving ecological benefits. The choice of the right mounting system, consideration of regional requirements, and professional installation are crucial for the success of such systems.
Let's shape the future of renewable energy together and utilize the advantages of ground-mounted photovoltaic systems. Invest in sustainable energy and contribute to protecting our environment and securing the energy supply of the future.
