How to install a photovoltaic system

Installing a photovoltaic system is a sustainable solution for producing clean energy independently and reducing energy costs.

Thanks to the [Decreto Bollette] ]Bills Decree, in force since 1 March 2022 and converted into the Law no. 34 of 27 April 2022, the procedure for installing solar panels and photovoltaic systems up to 200 kW has been simplified. Under the law, these installations are equated with ordinary maintenance work, with all the benefits that this entails.

To get started, you first need to choose the supplier best suited to your needs, who will carry out the technical checks necessary to design a customised system.

At this point, it is necessary to apply for permits, using a special form, called "Modello unico per la realizzazione, la connessione e l'esercizio di piccoli impianti fotovoltaici integrati sui tetti degli edifici" which is available on the website of the energy service provider or on that of the Ministry of Economic Development. Finally, the supplier must issue a Document of Conformity and a copy of the project. If the property is subject to environmental constraints, however, it is necessary to apply for a permit to install the system.

Where can photovoltaic panels be installed?

Photovoltaic panels can be placed on the roof, on the façade of a building or on the ground. Several technical aspects must be taken into account when deciding where to install photovoltaic panels. Although roof-top placement is the most common choice, it is good to know that photovoltaic panels cannot be fitted to all roofs. They are particularly well suited to pitched or flat roofs, where, however, it is necessary to install a supporting structure that angles the panels. Curved surfaces, on the other hand, are not particularly suitable.

During the inspection process, the installer will check feasibility, considering:

• The availability of the necessary space to install the modules. About six x 370 W photovoltaic modules are required for every 2 kW of power installed, and therefore, a typical 3 kW domestic system requires 9 panels, and needs about 16 m2 for pitched roof installation and about 25 m2 for flat surfaces. The size of individual modules may vary between manufacturers. On average, a photovoltaic module is approximately 1.7 m long and 1.1 m wide. The space required for installation depends on the number of modules to be used.

• The correct exposure should be towards the south, possibly south-east, south-west. The inclination of the surface should be between 10° and 35°.

• Any possible obstructions, such as trees or other constructions, which may cause shading and impair the efficiency of the system.

What permits are needed to install a photovoltaic system?

The installation of a photovoltaic system requires different procedures depending on whether the site to be used is free or, on the contrary, subject to environmental, historical, artistic or landscape constraints or on other parameters, such as whether the system will be visible or not from outdoor public spaces.

• The installation of a photovoltaic system requires different procedures depending on whether the site to be used is free or, on the contrary, subject to environmental, historical, artistic or landscape constraints or on other parameters, such as whether the system will be visible or not from outdoor public spaces.

• If the property falls within a listed area and the layout of the system requires it, a permit must be obtained for the installation of a photovoltaic system. In these cases, it is necessary to submit the project to the administration (usually the municipality on whose territory the system is to be installed) and request a landscape permit, a procedure regulated by Article 146 of Legislative Decree 42/2004. Once obtained, the landscape permit is valid for five years, within which time the work must be carried out, otherwise a new authorisation will be required. Recently the regulations have been changed and simplified, so in some specific cases of small-scale or fully building-integrated installations, authorisation for photovoltaics is no longer required. 

The installer will assess specific cases to advise and design the most suitable installation for every requirement. Even at this stage, it is important to select a partner with experience, able to assess specific cases to advise and design the most suitable intervention for every need.

Why buy a photovoltaic system?

There are many advantages to using photovoltaics, and the main ones are listed below:

• Respect for the environment: producing clean energy from a renewable source is a sustainable choice because it cuts the greenhouse gas emissions responsible for global warming.

• Convenience: the purchase of a photovoltaic system is convenient because it produces a saving on power bills due to the self-production of energy. Properties equipped with photovoltaic systems will be increasingly in demand on the housing market and their value will increase over time. In certain cases, these advantages can be extended by accessing incentives (such as the 50 percent tax relief for the renovation bonus) that make it possible to recover part of the costs incurred for the purchase and installation of photovoltaic panels.

• Reliability: the average lifespan of the system is about 25 years. Depending on the size of the system, it is possible to recoup the investment incurred for the installation within a few years. Periodic maintenance is very simple and keeps the efficiency of the system at the highest level.

• Increased energy autonomy: possibility of self-producing part of the electricity consumed when the sun is shining and increasing the available power of the house. Furthermore, if batteries are also integrated, it is possible to store the energy produced and not consumed for reuse at a later date.