Photovoltaic systems: complete guide to the most common questions

Photovoltaic systems are gaining more and more attention thanks to the growing demand for sustainable energy solutions.
In this article, we’ll answer the most common questions about solar systems — from costs and regulations to operation and fiscal opportunities.

What are photovoltaic systems and how do they work?

Photovoltaic systems are technological setups that convert solar energy into electricity.
This conversion occurs through photovoltaic panels that contain solar cells. These cells capture sunlight and, through the photovoltaic effect, generate direct current (DC).
An inverter then converts this energy into alternating current (AC), which can be used to power buildings and electrical appliances.
Photovoltaic technology is one of the most efficient solutions to reduce dependence on traditional energy sources, offering a clean and renewable alternative.

How can photovoltaic systems be classified?

Photovoltaic systems can be classified based on several criteria:

• By connection: grid-connected systems and stand-alone (off-grid) systems.

• By application: residential, commercial, and industrial systems.

• By installation type: Building-Integrated Photovoltaics (BIPV), directly installed on structures (roofs, walls), and traditional setups.

These categories are essential to determine the right system based on available surface and energy demand.

How much does it cost to install a photovoltaic system?

The cost of a photovoltaic system depends on several factors, including system power, panel type, and component quality.
Generally, for a residential home, the cost ranges between €6,000 and €10,000 for a 3–4 kW system.
Commercial and industrial installations are much more expensive — often reaching tens of thousands of euros — but they offer greater energy production and higher long-term savings.

It’s also important to factor in annual maintenance costs and the economic return from tax bonuses and energy bill savings.

Who works with photovoltaic systems?

Installing, managing, and maintaining photovoltaic systems requires the involvement of various professionals and specialized companies — such as solar installers, component suppliers (panels and inverters), and energy management firms.
These players ensure that the system operates efficiently, providing long-lasting performance and maximum energy savings.

What does a photovoltaic system installer do?

The installer is responsible for designing, assembling, and commissioning the entire system.
Their main goal is to ensure that panels are optimally positioned to capture as much sunlight as possible and that the system operates safely.
They also handle the electrical connections, inverter setup, and integration of storage systems. Once installed, the installer oversees system maintenance and performance monitoring.

What are the main types of photovoltaic systems?

The main photovoltaic systems are divided into different types, depending on energy requirements and installation structure:

Residential Photovoltaic Systems

These systems are designed for homes and meet domestic energy needs. They can be installed on rooftops, terraces, or other available surfaces.

Commercial and Industrial Photovoltaic Systems

Intended for businesses and production facilities, these systems are larger and produce higher amounts of energy — resulting in significant cost savings over time.

Building-Integrated Photovoltaics (BIPV)

BIPV systems are built directly into architectural structures, such as roofs and façades. They provide aesthetic and functional advantages, blending seamlessly into building design.

What incentives are available for photovoltaic systems in 2025?

In 2025, several European-level and national incentive schemes continue to support the adoption of photovoltaic systems.
While each EU country manages its own programs, most incentives share the same goal: promoting renewable energy production, reducing CO₂ emissions, and helping households and companies transition to energy independence.

Here are the main types of incentives available across Europe:

Feed-in Tariffs and Net Metering

Many EU countries still offer feed-in tariffs, paying system owners for the electricity they feed into the grid.
Alternatively, net metering schemes allow users to offset the electricity they generate with what they consume from the grid, lowering their overall energy bills.
Countries like Germany, France, Spain, and the Netherlands continue to update these frameworks to ensure profitability and fairness for small producers.

Investment Grants and Subsidy Programs

Several European governments and regional authorities provide upfront investment grants covering part of the installation cost — usually between 20% and 50%, depending on system size, location, and energy use.
These grants often come from EU recovery funds, regional sustainability programs, or national climate plans aligned with the European Green Deal.

Tax Deductions and Reduced VAT

Some EU member states offer tax credits or VAT reductions for residential and commercial solar installations.
For example, many countries apply reduced VAT rates (5–10%) on photovoltaic components and energy storage systems, making solar investments more accessible.

Support for Energy Communities

The Renewable Energy Communities (RECs) initiative, promoted by the EU, allows citizens, companies, and local authorities to share renewable energy produced locally.
Members can benefit from collective incentives, reduced energy costs, and financial support from EU and national programs that reward shared solar energy production and self-consumption.

Loans and Financing with Preferential Rates

To accelerate adoption, several European banks and public funds offer low-interest or zero-interest loans for solar projects.
These financing options are designed to make the initial investment affordable and support long-term energy transition goals.

What is the role of the inverter in a photovoltaic system?

The inverter is the heart of a solar system. It converts the direct current (DC) generated by solar panels into alternating current (AC), which powers homes and businesses.
Without the inverter, the electricity produced by panels couldn’t be used. It also helps optimize energy yield and allows for system performance monitoring.

How can someone become a photovoltaic system installer?

Becoming a certified solar installer requires specific training in renewable energy technologies and electrical safety.
In Italy, professional courses provide official certifications, allowing qualified individuals to design, install, and maintain photovoltaic systems.
A solid understanding of electrical standards and installation safety is essential.

Who defines the maintenance frequency for photovoltaic systems?

Maintenance frequency is typically defined in the service contract between the installer and the client.
However, regional or national regulations may impose minimum maintenance requirements.
Generally, systems should undergo at least one annual inspection to ensure optimal performance and prevent damage or inefficiencies.

Conclusion: Why should you invest in a photovoltaic system?

Photovoltaic systems are a smart investment — both economically and environmentally.
For households and businesses alike, installing solar technology means cutting energy bills and producing clean, renewable power.
With tax incentives, adopting solar energy has never been more convenient.

Photovoltaics represent one of the most sustainable paths toward reducing CO₂ emissions and building a low-carbon future.
As technology evolves — with bifacial panels and energy storage batteries — solar systems will become even more efficient and versatile, making them a strategic investment for the years ahead.

If you’re considering installing a photovoltaic system, now is the right time.
Take advantage of available incentives and start saving while contributing to a cleaner planet.
With the support of qualified professionals and trusted installers, you can find the perfect solution for your energy needs — and enjoy the long-term benefits of sustainable power.