Photovoltaic systems: how many kW? Our tips

When you decide to install a photovoltaic system, one of the first questions to ask yourself is: how many kW do you need to cover your energy needs? The answer depends on several factors, such as your family's consumption, the available surface and the efficiency of the system. In this article, we'll review everything you need to know to choose the right plant, with a focus on the benefits and alternatives offered.

Average household consumption

To properly size a photovoltaic system, it is essential to know your family's average annual consumption. In Italy, a family of three or four people consumes an average of between 2,700 and 3,500 kWh per year. This value may increase if you use particularly energy-intensive appliances, such as air conditioners, dryers or heat pumps.

If your consumption falls within this range, a 3 kW system may be sufficient. However, if your home has an electric heating system or you plan to install a charging station for electric cars, you may need a larger system, such as 6 kW.

Difference between kW and kWh

A common mistake is to confuse kW and kWh, two units of measurement linked to energy but with different meanings. The kilowatt (kW) measures the power, i.e. the maximum production capacity of a photovoltaic system at a given time. A 6 kW plant, for example, can generate up to 6 kilowatts of power under optimal conditions.

The kilowatt hour (kWh), on the other hand, measures the energy consumed or produced over time. For example, if you use a 1 kW air conditioner for an hour, you will have consumed 1 kWh. When evaluating a photovoltaic system, it is important to understand how much energy (kWh) it will be able to produce over the course of a year.

How many photovoltaic kW per 100 square meters?

The available surface on the roof is another crucial element in determining the size of the installation. On average, about 8-10 square meters of space are needed for every kW installed. Then, on a roof of 100 square meters, it is possible to install a system of about 10-12 kW, depending on the layout of the panels and the possible presence of obstacles such as chimneys or antennas.

For a 100 sqm house with standard annual consumption, a 6 kW system could be an ideal choice, ensuring adequate energy coverage and a good ratio between occupied space and power generated.

6 kW system: coverage and requirements

A 6 kW photovoltaic system is suitable for families with annual consumption between 4,000 and 6,000 kWh. This type of plant can produce between 7,000 and 9,000 kWh per year, depending on the geographical location and exposure of the roof.

For example, in southern Italy, where solar radiation is higher, a 6 kW plant can generate up to 9,000 kWh per year, covering not only the electricity consumption of a family, but also that of a possible heat pump or an electric car.

6 kW photovoltaic system: turnkey price

The cost of a 6 kW photovoltaic system varies depending on the materials used, the complexity of the installation and the incentives available. On average, the turnkey price is between 9,000 and 12,000 euros, including panels, inverters, assembly structures and labor.

Thanks to state incentives, such as the 50% tax deduction, the net cost is reduced to around 5,000-6,000 euros. Added to this is the annual savings in the bill, which can exceed 1,500 euros, making the investment convenient in the medium to long term.

To better calculate everything, we have made available on our site a free cost and earnings simulator from photovoltaic systems: you can find it here.

Risks and alternatives

Although photovoltaic systems offer many advantages, there are some risks to consider. For example, incorrect installation or poor quality materials can reduce plant efficiency and lifespan. In addition, not everyone has the opportunity to install panels on their roof, especially those who live in condominiums or rental houses.

For those who cannot or do not want to face the initial investment, GridShare represents an innovative alternative. The platform allows you to invest in shared solar energy projects, obtaining an economic return based on the energy produced by the financed plants. This model is ideal for those who want to contribute to the energy transition without the complexities associated with installing a domestic system.

Understanding how many kW you need for your photovoltaic system is essential to maximize savings and optimize investment. With a correct assessment of consumption, available surface and costs, you can choose the system that best suits your needs. And if you're looking for an alternative to home installation, GridShare offers a flexible and sustainable solution to participate in the solar revolution.

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