Solar panels are rectangular and flat devices that are intended to absorb solar radiation to transform its energy into electricity. The process is the following: the sun’s rays fall on the plates and they convert light into electrical energy through the photons that compose them. Subsequently, this energy that has been generated will be able to feed the various types of electrical charges.
Main types of solar panels in Spain
Solar panels are different types of devices that capture solar energy, although we must distinguish between those used to generate heat, those used to produce electricity and hybrids:
- Photovoltaic panels: they are used to produce electricity.
- Solar thermal panels: they are used to heat wáter, generally for domestic purposes such as heating the house, heating the pool or using it as domestic hot water.
- Hybrid solar panels: they combine the functions of the previous two, taking advantage of the same surface area to produce heat and electricity.
Photovoltaic panels
There are numerous ways to classify photovoltaic panels, since they could be distinguished according to the type of use, the technology used, the dimensions, the power, the size, etc.
What voltages do photovoltaic solar panels have?
Solar panels with 12 volt voltages are usually small panels and for very specific applications, such as charging the battery of a motorhome.
Solar panels of 24 volts or more are the most common for residential and commercial self-consumption. On the other hand, 48 volt panels are usually used for larger industrial self-consumption installations.
The solar panels that are installed in the vast majority of current photovoltaic systems are reduced to the following types:
- Monocrystalline silicon panels
- Polycrystalline silicon panels
- Amorphous silicon panels (thin layer)
Monocrystalline and polycrystalline solar panels typically have the highest efficiencies and power capacity. However, monocrystalline solar panels can achieve efficiencies greater than 20%, while polycrystalline ones usually have efficiencies between 15 and 17%.
Also, monocrystalline panels tend to generate more power than other types of panels, due to their efficiency and because they also come in higher power modules. Polycrystalline panels tend to have lower wattages. This means that even though both are the same size, monocrystalline panels are capable of producing more electricity.
On the other hand, amorphous silicon solar panels tend to have lower power efficiencies and capacities than the above mentioned due to the lower quality of silicon used.
Price of the different types of photovoltaic solar panels
Because the manufacturing processes of the different types of panels are different, their price also varies.
Of all the types of solar panels, monocrystalline solar panels are the most expensive option. On the other hand, polycrystalline solar panels are usually cheaper than the previous ones mentioned.
Thermal solar panels
Solar thermal panels have the function of heating water for domestic use. The two main types of solar thermal panels are:
- Vacuum tube solar panels
- Plate or flat solar panels
Hybrid solar panels
These combine the functions of photovoltaic panels and thermal panels, taking advantage of the same surface area to produce both heat and electricity.
The combination of the two technologies means that the proportion of energy used per square meter increases. Therefore, hybrid systems can be attractive in places where space is limited and where there is a need to be more energy efficient.
Although there is a higher utility per square meter, the efficiency of electricity production and heat production in a hybrid system is generally lower than that of pure heat or electricity systems. The price, complexity and efficiency of hybrid systems vary greatly, since being a more complex technology, they also require more maintenance than photovoltaic panels.
Uses of solar panels
There are many reasons to install solar panels in a home, since they are a very versatile energy solution. Solar panels have many uses in the home and even for public lighting or transportation.
In fact, these are mainly used for household appliances, heating, hot water, air conditioning, swimming pools, electric cars, etc.
Is it profitable to install solar panels in Spain?
The profitability of solar panels in Spain is determined by the price of the system, the aid that can be obtained and the amount of energy produced. In the case of Spain, with an average of 1,300 hours of sunshine per year, the potential for generating electricity is very high.
In addition, the central government and the different local administrations throughout the territory are promoting photovoltaic self-consumption by making available aid in the form of a reduction in personal income tax, IBI and ICIO rebates or other aid.
However, the profitability of solar panels without these aids is high due to the simple fact that the energy is self-consumed. Companies or homes that choose to self-consume may notice a drop in the electricity bill of up to 50%.
Therefore, the annual profitability of a self-consumption system is 10% – 15%.
