How the energy production of solar panels varies throughout the year


The variability of solar panels and their electricity generation throughout the year is influenced by the different levels of solar irradiation received during each season. Additionally, the size and orientation of the solar panel plays a crucial role in determining its performance.

In this article we are going to tell you How the energy production of solar panels varies throughout the year and what aspects you should take into account.

How the energy production of solar panels varies throughout the year

photophotonic cells

Throughout a year, various factors come into play that can influence the performance and electrical production of solar panels. When it comes to electrical production from solar panels, Numerous factors can influence the amount of energy they generate. However, these are the categories of factors:

  • The amount of solar irradiation at the specific location
  • The orientation of the roof or the surface where the panels are installed
  • Presence of shadows during certain seasons
  • The average temperature experienced in the area.

What specific solar panel attributes impact its ability to generate electricity?

When determining the power output of a solar panel, the main factor to consider is its maximum peak watts (Wp), which represents the greatest amount of power it can generate.

The manufacturer's maximum rating refers to uninterrupted direct current (DC) flow under typical circumstances. The procedure to carry out these evaluations is as follows:

  • There is an influx of 1000 megajoules of solar radiation per square meter,
  • There is an atmospheric temperature of 25ºC.

The appearance of these precise conditions is not an everyday phenomenon throughout the year, so it is necessary to consider the presence of a climatic element beyond our control. However, the standardized format provided by the European Commission's PVGIS remains applicable in all cases.

The composition of solar panels involves the combination of multiple photovoltaic cells. As for residential solar panels currently on the market in 2021, they have a power rating ranging between 350 and 455 Wp (watts peak) and They are composed of approximately 66 to 96 photovoltaic cells. Additionally, a larger option is available that can output up to 500 watts peak.

Naturally, the level of electricity generated by a solar panel is directly proportional to the voltage specified by the manufacturer. The generation of electricity from solar panels is subject to seasonal variations throughout the year.

It is important to recognize that the provinces They do not receive equal amounts of solar radiation, and the same goes for the variation in seasonality within these provinces.. Therefore, we must consider that its productivity differs between summer and winter.

At what point do solar panels start the energy generation process?

How the energy production of solar panels varies throughout the year

From the moment the first rays of sun emerge, solar panels begin generating energy. However, the amount of energy produced fluctuates throughout the day and culminates at noon, when the sun reaches its zenith. While it is vital to recognize that energy is also generated in the morning and afternoon, it is imperative to understand that the intensity of Solar radiation varies according to the position of the sun in the sky, which affects the production of our photovoltaic system.

When considering the installation of photovoltaic solar panels, one of the first doubts that arises is the amount of sun that Spain receives. Fortunately, Spain has a substantial amount of sunshine each year, making it an optimal place to harness solar energy. On average, our nation experiences a range of 2200 to 3000 hours of sunshine per year, depending on the specific autonomous autonomy per community. This ensures an ample supply of solar radiation, solidifying solar energy as a lucrative and reliable investment.

In Spain, peak hours of solar radiation usually coincide with midday and early afternoon. Examining the regions of Andalusia and Murcia, located in the southern part of the country, one can see ideal circumstances for harnessing solar energy. However, it is important to note that these conditions may vary depending on the time of year.

The distribution of solar production per month in Spain is as follows:

  • Solar production experiences a decrease from January to March, followed by a subsequent increase from April to June.
  • During the months of July and August, solar production reaches its peak, providing maximum energy performance. As the calendar moves towards September and continues into December, there is a gradual decrease in solar production, resulting in a decrease in the amount of energy generated.

Regardless of fluctuations, photovoltaic solar panels can offer substantial performance throughout the year in our country. However, the length of daylight hours plays a crucial role in maximizing profitability.

Energy production from solar panels depending on orientation

solar energy production

Orientation also affects solar energy production. The two main directions are south and east-west. Here we describe both cases in detail.

  • South: In general, the south is the most common. If it is possible to orient the panels in this direction to maximize the production of solar energy in Spain. This ensures that the panels receive maximum sunlight throughout the day.
  • East-west orientation: If you cannot place the panels facing south, an east-west orientation may be a good option. East-facing panels capture morning light, while west-facing panels take advantage of afternoon light.

Despite these guidelines, the best orientation of solar panels depends on several factors. Therefore, it is necessary to carry out a personalized study to determine the best installation method for your home, ensuring you get the maximum performance from your photovoltaic installation.

I hope that with this information you can learn more about how the energy production of solar panels varies throughout the year.

Leave a Comment

Your email address will not be published. Required fields are marked with *



  1. Responsible for the data: Miguel Ángel Gatón
  2. Purpose of the data: Control SPAM, comment management.
  3. Legitimation: Your consent
  4. Communication of the data: The data will not be communicated to third parties except by legal obligation.
  5. Data storage: Database hosted by Occentus Networks (EU)
  6. Rights: At any time you can limit, recover and delete your information.