The amount of energy we consume It will determine the number of solar panels that we will need if we choose to install solar panels in our home. Therefore, it is important to know not only how much energy we consume, but also how much energy a solar panel produces. In this way we will be able to optimize the number of photovoltaic panels to be able to save as much as possible on our electricity bill and generate less impact on the environment.
Power produced by domestic panels
How many kWh does a solar panel produce is one of the common questions that arise when we think about self-consumption. This will also determine the cost, as well as the space required for installation. The power generated by solar panels is measured in watts (W) and it will depend on the type of panel, since they have different powers just like a computer has different capacities depending on the model.
The power is indicated in the technical sheet of each panel in question, however, the Medium power of solar panels ranges from 250 W and 300 W of energy. It is also common to find panels in homes with high powers such as 500 W and in turn some of lower powers such as 150 W.
If we take a 300 W solar panel as our starting point, this means that for every hour of sunshine we will obtain that power. Let’s suppose that we take as a reference a sunny day in a warm area, the calculation would be as follows:
- 300 W x 5 hours of sunshine a day = 1500W or what is equivalent to 1.5 kWh a day.
With these data we can estimate the annual hours of sunshine, as well as the kWh that our installation could generate. As an annual average, compensating for the hours of less sunshine in winter and the hours of more sunshine in summer, we have as a result about 5 hours of sunshine a day on average.
- 1.5 kWh per day x 365 days per year = 547 kWh per year for a 300 W solar panel.
If the solar panel we choose has more or less power, we will only have to change it in the formula to know the amount of energy it produces.
Importance of the hours of sunshine
Clearly this calculation is a approach to the amount of energy that a solar panel can produce, since it will not be the same to live in southern areas such as Malaga or Seville than in northern cities such as Bilbao or Santander. Keep in mind that when we look at the watts of the solar panel and see 200 W or 300 W, the manufacturer refers to the power generated by the solar panel in optimal conditions, which is obviously not going to happen every day of the year.
In summer we can have the same number of hours of sunshine in Bilbao or Malaga, but the hours of sunshine are actually very different. The incidence of the sun it is more powerful in warm areas so it is more than likely that the solar panel will approach the optimal power more often. The good news is that constant advances allow solar panels, even on a cloudy day, to be able to extract energy.
As a summary, when it comes to knowing how much power a solar panel actually generates, we should take into account three aspects: the power, the hours of sunshine, and the incidence of the sun in the place of residence.