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Calculate power and size of solar panel


The solar photovoltaic installations have experienced a great boom in recent years. Faced with the continuous rise in the price of electricity, both individuals and companies are betting on this alternative energy source. However, some doubts arise regarding the maintenance of solar panels or the size and power of the panels for higher performance.

Solar panels can be placed in a conventional home or a business, although there are other places such as a camping or a shed in the field where they can also be used. In each case, the needs are different, for this reason; calculate the power and size of the solar panel is essential in terms of photovoltaic production.

The relationship between the power and the size of solar panels

For know the power that a solar photovoltaic installation must produce, it is necessary to know the space available on the roof. Normally, the average of a solar panel is 1.9 m2. While the power is expressed in peak watts (Wp). Therefore, if it increases, the dimensions of these solar panels must be larger.

The importance of power in solar photovoltaic installations

Our country continues to advance in the process of energy transition, according to last year’s data, renewable energies are in one of their best moments. The power of this technology has increased by 29% (3,300 MW), an action that has favored electricity production by more than 37%. This is how it is collected in Preview of the 2021 Spanish electricity system reportan annual document, published by the Electricity Network of Spain.

Photovoltaic panels have an output power that varies between 300 and 650 watts, mainly. In other words, this would be the maximum power that a panel could reach according to standard measurement conditions.

It is evident that according to power choice, the performance will be affected. For example, a 250W panel has an energy efficiency of 14.7%, while a 400W board has an efficiency of 20%.

Taking these data into account, it is necessary to know that the usual power that is usually used in a home, or even an urban garden, is around 350 W or 450 W. This will depend on the size of the roof or cover, the surface in which for the installation to take place.

For this reason, knowing how much energy a solar panel can produce is a determining factor. On sunny days, greater energy production is generated, however, there is a formula that offers data with greater precision. would have to multiply the installation power by hours of sun to know the production.

For example, if the plate is 350 W and 4 hours of sunshine per day are calculated, the final result will be 1400 Wh/day. However, if the panels are not of good quality, the most normal thing is that they produce less energy and profitability would be affected.

Calculate solar panels and their size for a photovoltaic installation

As the power and quality of solar panels influence energy production, it is also useful to know how many panels are needed for an installation. To begin with, it should be noted that energy needs are not the same for a medium-sized home as for an industrial warehouse.

And, on the other hand, in the solar panel market there are many options depending on their measurements, technology and power. However, in order to decide the size of the solar panels, you have to know the available surface of the roof. Also, you have to know if there are physical obstacles or shadows, as they would limit its power.

The standard size of a solar panel is usually 1.7m x 1.00m. Although, this also depends on the brand and manufacturer. However, it should be noted that these plates have similar dimensions depending on their type.

  • Panels polycrystalline Y monocrystalline they have a height of 170 to 230 cm and a width of 100 to 130 cm, with powers of 300 to 650 Wp.
  • Finally, it should be noted that there is also panels of other powers with different measures than the previous ones.

It is evident that a larger solar panel will have more possibilities to produce solar energy. However, a small house will not have the need to install large panels, unlike what would happen with an industrial warehouse.

On the other hand, large panels often have a structural weakness, which is not as common in a smaller panel.

If the space is insufficient or does not meet the characteristics to provide the best functionality to a surface, it is always convenient to assess install high-efficiency panels. This option allows more energy to be generated per square meter and offers a conversion rate of over 20%.

Ultimately, the solar panel dimensions and his power they are closely linked. However, it is best to put yourself in the hands of an expert technician in the field so that he can carry out a project with all the guarantees. We hope to have helped you in calculating the power and size of the solar panel.