Biosolar photovoltaic panel mounting system

The Biosolar system is an integrated photovoltaic solution developed specifically for extensive, semi-intensive, and biodiverse green roofs.

The combination of green roof and solar technology creates a complementary system in which the two components mutually support each other, ensuring both the production of renewable energy and the maintenance of favorable conditions for biodiversity.

This professional solution allows the installation of photovoltaic panels on green roofs or on the Blueroof system, suitable for both new and existing buildings. Installation is recommended on extensive, semi-intensive, and biodiverse green roofs, with careful selection of plant species to avoid shading of the panels by tall vegetation. The system offers flexibility in configuration, allowing panels to be placed over the entire roof surface.

Advantages of the biosolar system

The system’s performance is optimized due to the natural cooling effect generated by the green roof vegetation, which can increase efficiency by approximately 10–20%. The yield of photovoltaic panels is directly influenced by ambient temperature, with high temperatures reducing efficiency; for example, on a bituminous roof, summer temperatures can reach up to 90°C. The elevated structure of the modules allows light penetration and helps maintain adequate humidity levels for the vegetation. The system is designed not to affect the waterproofing, with installation performed without perforation, using ballast formed by substrate and vegetation. Properly dimensioned, the system can withstand wind gusts up to 150 km/h, with each project evaluated individually.

It generates green energy, protects the environment, and last but not least, significantly reduces electricity bills.

The green roof, among other anti-pollution properties, captures microparticles and dust from the air, keeping the surrounding atmosphere cleaner. Photovoltaic panels in this environment remain cleaner, their maintenance is simpler, and they absorb more energy = produce more useful electricity.
However, we must not forget that installing solar panels on an existing green roof or vice versa, creating a green area under already existing photovoltaic panels involves several demanding and sensitive work phases regarding the roof waterproofing or the panel connections and wiring. Therefore, the optimal solution is the construction of the extensive green roof in combination with the assembly of solar panels in the phase preceding the installation of the green terrace, thus generating lower costs through the efficiency of the installation and maintenance process, and ensuring uniform weight distribution on the other hand.

The solution in which the installation of solar panels is integrated into the development of a multi-layer extensive green roof is presented as follows:

A protective layer, closing layer formed by a root-resistant membrane that resists the aggressive action of roots (in case the waterproofing does not have FLL root-resistant certification).
Protective layer, geomembrane made of polyester fibers or mechanically reinforced mixture of polyester and regenerated polypropylene, with a water absorption rate between 3 and 6 l/m², depending on the product.
Photovoltaic panel support module, specially designed for quick installation. Photovoltaic panels of 1,000 mm, 1,200 mm or transversely 1,600 mm can be easily installed, but the sliding fixing elements allow adaptation to any photovoltaic panel size. The panel supports are made from recycled high-density polyethylene (HDPE), while the other components are made from durable materials such as Magnelis®, aluminum, and stainless steel. The panels will be fixed on these supports above the vegetation layer of the roof. The entire system complies with the requirements and standards of the European Union.

The implemented system supports sustainable development objectives and contributes to ecological certifications such as BREEAM and LEED, providing additional points useful for obtaining excellence ratings.

Photovoltaic panels

They are installed in this phase to avoid intense subsequent traffic. Assembly is done according to the manufacturer’s specifications, with the supports compatible with most models.
Control boxes are installed for inspecting the condition of the lower layers and checking rainwater drainage openings, with adjustable height, with upper and side openings for drainage.
The vegetation substrate is spread in thicknesses between 60–200 mm, depending on climatic conditions and the type of vegetation used, to ensure a sufficiently deep growing medium for plant roots, which is crucial for their survival and development, as well as for ballasting the panel supports.
The substrate composition usually includes recycled as well as natural materials, such as brick rubble, perlite, pumice, volcanic slag, peat fibers, ground biodegradable plant fibers typically in granulations between 1–40 mm. The most important criteria for choosing a particular type of substrate will be: water storage capacity, which in this case should reach the highest possible values, up to 40% of volume, permeability, and structural stability.

The actual vegetation layer

For extensive green roofs, plants resistant to large temperature variations, extreme conditions, frost, lack of precipitation, drought, wind, acid rain, etc. are recommended. Various sedum species and wild grasses are ideal for the role of vegetation on an extensive green roof, but they can also be combined with several types of flowering plants to achieve truly spectacular landscape decorative results. There are several ways to plant or seed extensive vegetation, but the most effective method, both in terms of material and execution time, is the use of vegetation rolls.
Seeding or dispersing sedum cuttings/pieces to root in the soil is an apparently cheaper method, but the effort of irrigation and maintenance until maturity exceeds several times the cost of the vegetation roll, which already provides over 95% coverage upon installation, being immediately resistant to heavy rainfall – something that cannot be said about the seeding method, where in the case of a torrential rain the risk of compromising the entire plantation is very high. Sedum/wild grass vegetation rolls, once spread, root quickly (10-14 days) into the substrate. The vegetation roll has a three-dimensional root structure and a significant amount of well-drained but fertile special soil, so under normal conditions, one year after installation, the extensive ecological roof reaches maturity. Once installed, they protect the entire green roof layering from all adverse weather conditions that may occur.

Installation of biosolar panel supports

It is recommended to place the panel supports at a distance of min. 1.5–2 m between rows (ensuring sufficient space for green roof maintenance, preventing accidental damage to the panels, and also ensuring that the panels do not shade each other). Installation by 2 specialists is recommended, who must coordinate during assembly (the supports are integrated into the green roof by green roof specialists, while the panels, cabling, inverter, and grid connection are handled by authorized electricians). The load-bearing capacity of the roof must be checked before installation to support at least 170 kg/m² (weight of supports ballasted with green roof layers + weight of panels, cables + a reserve margin).
To find out the costs of a biosolar type green roof, request a personalized quote by providing as many details as possible (plans, projects, sections, or just photos and descriptions of your project). Orientatively, the cost of one panel support (which can support a single photovoltaic panel) with the green roof system that ballasts it can range between 240–270 Euro + VAT (covering approx. 1.6 m² at roof level). Larger projects benefit from volume discounts, while smaller ones have additional costs due to logistics expenses distributed over a smaller area/number of panels.

We provide consultancy for the realization of green roofs and terraces with solar panels, offering multiple advantages and positive effects on the environment, reducing expenses related to maintaining thermal comfort in a building, providing sound insulation, and relieving the drainage and sewerage system from overload by rainwater.

We are at your disposal from the design phase so that you can benefit from optimal solutions for each green roof project. We undertake turnkey execution and long-term maintenance of extensive and intensive green roofs and terraces using durable construction materials and specially cultivated vegetation rolls for green roofs, whether extensive, intensive, or landscape type. Each green roof realized by us will have the best cost/efficiency/safety ratio, offering you customized green roof system solutions tailored to your specific project. This can be an industrial hall designed with an extensive vegetation green roof, or an office building with an intensive green terrace featuring recreation and rest areas, or a shopping center with intensive landscape-type green roof parking on the building’s roof. Regardless of whether you want an extensive or intensive green roof, landscape or garden type, or if the load-bearing structure of the existing roof requires an ultra-light or light vegetation roof, if you want the ecological function of the green roof to be complemented by the installation of solar panels, or if you desire a vertical garden placed on interior or exterior walls, we are at your disposal with projects, system solutions, green roof estimates, and professional consultancy.