Solar rooftop mounting systems
The mounting structure of solar rooftop systems depends on the type of cover:
Pitched roof mounting systems
when it comes to residential solar installations, solar panels are often found on sloped rooftops. Solar mounting systems for pitched roofs usually uses rails attached to the roof through shaped profiles anchored with bolts or screws under the roof tiles. PV panels are positioned on the rails and fixed with clamps.
Commercial and industrial solar applications are often found on large flat rooftops. Solar mounting systems for flat roofs are commonly ballasted with few penetrations. Concrete blocks weight and position, and pv panels tilt (usually between 5oand 15o) are chosen according to the resistance of the roof and to prevent wind lift or other movement.
typical of industrial roofs. PV panels are mounted on the sloping side of the sheds with structures equivalent to those used for pitched roofs, but directly anchored to the shaped metal sheet.
In addition to the classic polycrystalline flat panels, flexible thin film panels with lower producibility, but more aesthetical adaptability, can be used.
PV modules can be also used to replace conventional building materials in parts of the building envelope (BIPV - Building-integrated photovoltaics).
Considerations on weight of the rooftop solar systems
On average, the distributed weight of conventional solar photovoltaic (PV) panels is about 30-60 Kgs/m2. The number and position of the load points must be appropriately calculated but generally such loads are acceptable.
Other main components
Inverters (string type) are usually mounted on the outer wall of residential buildings, or directly on the roof for commercial/industrial buildings, but they can also be installed in special technical rooms, together with electrical cabinets and other main components.
Excluding any incentive rates, the biggest advantage of a solar rooftop system is the possibility to consume directly the energy produced by the pv plant (self-consumption), thus allowing you to reduce the energy taken from the grid and thus the cost of the electric bill.
To determine self-consumption, the average consumption of utilities/appliances must be compared with the amount of energy generated by the solar rooftop system.