May 17, 2022
Yara Bakker

Solar panels: how, what and why

Would you like to generate your own energy? In that case, you might have already considered buying solar panels. From January 2023, it will be even more attractive to do so in the Netherlands. This is because from then on, there will be no more VAT on solar panels.

Solar panels: they can often be seen on the roofs in new residential areas. However, more and more inhabitants of older houses are switching to this more sustainable way of generating energy. With the sharp rises in gas prices, this choice is also becoming increasingly profitable from a financial point of view.

From 1 January 2023, there will be an extra incentive to make the switch. From then onwards, consumers no longer have to pay tax on the purchase and installation of solar panels. But what aspects should you consider before making the investment? We will discuss it in this article.

How do solar panels work?

Solar panels consist of numerous solar cells, which convert the infinite energy that the sun sends to the earth into electricity.

These solar cells are made from a semiconductor called silicon. This material only conducts electricity when light falls on it. In this case, the sunlight that shines on the panel generates direct current (DC). This is an electric current between the negative charge on the bottom of the cell and the positive charge on top of the cell.

However, this current still has to be converted into alternating current (AC) by the inverter. This is the kind of power that comes out of our electrical outlets and that we are all familiar with. The inverter is connected to your group box and ensures that the generated power is sent to the electricity grid, so that you can use it.

Solar panel field

Which kinds of solar panels are there?

Thermal vs. Photovoltaic Solar Panels

When we talk about solar panels (like in this article), we are usually referring to photovoltaic solar panels. These are panels that convert sunlight into electricity.

Note, however, that there also exist thermal solar panels (also called solar collectors). These panels convert solar heat into a liquid. Thermal solar panels achieve an efficiency of no less than 60%, while this is only about 20% in the case of photovoltaic panels. It is therefore worthwhile to consider thermal solar panels when you want to use them for hot water or heating. If this is not the case, we recommend that you opt for photovoltaic solar panels.

Solar panels on a roof
Types of Photovoltaic Solar Panels

When purchasing photovoltaic solar panels in the Netherlands, you are usually making a choice between monocrystalline and polycrystalline panels. There are also a number of new types of panels, but these are currently too expensive and/or generate too little energy to be profitable. We will briefly discuss each option below.

  • Monocrystalline panels

With this type of solar panel, the functional layer consists of a single silicon crystal. Monocrystalline panels are generally black in colour. There are also small checkered areas between the cells, although you are not able to see those from a distance. The efficiency of monocrystalline panels is somewhat higher per square metre, and this type also generally performs slightly better in cloudy weather. This difference is also reflected in the higher price. However, when it is very hot, the opposite is the case. As the aforementioned differences in performance and pricing are not that big, most people mainly pay attention to the appearance when purchasing.

  • Polycrystalline panels

You probably guessed it: with polycrystalline panels, the functional layer consists of several silicon crystals. You can generally recognize these panels by their blue color and the fact that they look like a grid, with the crystal planes clearly visible from a distance. As discussed above, these panels perform slightly worse in cloudy weather, but slightly better in hot weather. Polycrystalline panels are generally a bit cheaper.

  • New types of panels

The new types of panels available are the thin film CI(G)S solar panel, the glass-glass solar panel, the bifacial solar panel and the hydrogen panel. It is currently not profitable to opt for these types of solar panels for the energy supply of a home, so we will not discuss them in detail in this article. However, this may change in the future.

What should you pay attention to?

First of all, it is important to think carefully about the placement of the solar panels. You have to pay attention to the slope of the roof and the amount of shade, for example from a tree that is standing next to the house.

  • The direction and slope of the roof

Not everyone has the opportunity to adjust the angle of inclination for the solar panels on their roof. However, if this is the case, it is recommended to lay them at an angle of inclination of 35 degrees. If you have not chosen an optimal angle of inclination (10 – 60 degrees), you will lose 10 – 20% of power (this depends on the chosen orientation for the panels).

It is also best to lay the panels in the direction of the south, because this way you catch the most sun and get the best return. If you lay the panels in the direction of the east or the west, you will lose up to 20% of power. In the case of the southeast or southwest, this is 10%.

  • The presence of shadow

The solar cells of a solar panel transfer the energy to each other so that it eventually ends up at the inverter. When part of the solar panel is in the shade, it becomes harder for the electrons to pass through. In this case you are, as it were, missing a link from the series-connected system. Even if only one panel is partially in the shade, this can have a negative effect on the yield from all surrounding solar panels in the set.

Why solar panels?

There are roughly two reasons to switch to solar panels: environmental friendliness and cost savings.

  • Environmental friendliness

Unfortunately, our traditional ways of generating energy use fossil fuels, which release a lot of CO2. Despite the fact that the production of solar panels is also associated with CO2 emissions, this does not outweigh the savings by far. It has been found that if you own a set of 10 solar panels, you save 1,200 kilos of CO2 annually. Since solar panels generally have a lifespan of about 25 years, you can assume that you are making a sustainable choice when you make the switch.

  • Cost reduction

Even though the purchase is quite expensive, it generally pays off in the long term to switch to solar panels. This is because you will then reduce your monthly costs a great deal, which means that this option is much cheaper in the end.


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