With Sun Ballast, photovoltaic systems become more systems become safer and more cost-effective: interview with Technical Director Andrea Calza
The selection of the right mounting structures will also be a key moment in realizing photovoltaic systems on flat roofs, and in this short interview, Sun Ballast’s Technical Director Andrea Calza explains some of the main advantages of concrete ballasts.
Andrea, your concrete photovoltaic structures are already known and used internationally: what are the winning features?
Sun Ballast ballasts for photovoltaic panels are currently a really important product in structures for flat roof photovoltaic systems, and we have already sold more than 4 million units. Today, the Sun Ballast catalog offers more than 40 solutions with different inclinations, configurations, and weights, and accessories can be integrated into each system to quickly vary the total weight and its distribution on the roof of the building. Simplifying our customers’ work has always been our most important goal.
Let’s take some concrete examples: many buildings have low load limits, and it is not always easy to respect them while guaranteeing adequate panel strength, especially in very windy areas. What solutions do you propose in these cases?
Our range offers several solutions that limit the weight, without perforating the roof and guaranteeing high wind resistance. Lattice systems – such as Connect, Industrial-XL, or EasyWest – are a winning option from this point of view: the combination of all the structures in a single truss makes it possible to use lighter ballasts, relieving the mechanical stresses caused by weathering not on a single row or panel, but on the entire network of structures. In this way, a very high degree of watertightness is achieved, but the weight on the roof remains very limited. Many solutions make it possible to stay below 20 kg per square meter.
In cases where it is necessary to increase the load on structures – for example, to withstand very intense disturbances – what kind of solutions do you offer?
Since 2012, we have supplied structures for more than 50,000 PV systems, and many of them have been installed in very windy areas, such as coastal areas and islands in the middle of the ocean. In these cases, the use of accessories can be of great help: U-Block supplementary counterweights – 15 and 30 kg – can, for example, be placed directly on the ballasts – from those of the single-row system to those used for the Sail and Connect systems – and allow the point load and watertightness of the structures to be increased in a matter of minutes. In addition, the Cablowind system – a special concrete channel attached to the back of the ballasts – not only accommodates the electrical cables inside the ballasts but also binds the structures together, better distributes the weight, and maximizes system strength and reliability. Cablowind is typically used in single-row systems but is also compatible with “classic” east-west and sail systems.
Returning to lattice systems, at the last Intersolar the EasyWest system, the new Sun Ballast East-West, was presented: what are the advantages of these structures in terms of load management?
The photovoltaic structures of the new EasyWest system are designed precisely to limit the weight of photovoltaic systems as much as possible: the two ballasts that make up the system weigh only 28 kg, the weight per square meter is kept below 20 kg/m² and the panels – even if they are large – remain anchored with great stability even without the use of accessories. The new steel clips also do their job, and in addition to increasing the holding of the modules, the PowerClamps also act as an electrical bridge, making all grounding operations much faster. The new system also takes up the grid structure already used in the Connect and Industrial-XL systems, and offers a great balance between roof load and wind resistance.
In conclusion, how would you advise those who choose to use ballasts for photovoltaic panels in installations on flat roofs?
It is certainly essential to collect and analyze all the data relating to the type of roof, the sizing of the system, and the most suitable support structures for photovoltaic panels for installation. From this point of view, our technical department prepares more than 20,000 technical reports every month, complete with wind and roof load calculations, and accompanies customers in all phases of implementation: from planning to the choice of concrete ballasts, through to installation suggestions. This free, complete, and professional service greatly simplifies and speeds up the work of designers and installers, and is not only a great satisfaction for us but also one of the strengths that, after more than ten years, continue to make Sun Ballast the reference brand in the field of structures for photovoltaic systems on flat roofs.
