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The Solar Energy Portal

Photovoltaic solar panels

The  photovoltaic solar panels  have more and more prominence in our lives. The energy transition is promoting the use of alternatives that help lower the carbon footprint. In addition,  photovoltaic solar panels  have a multitude of uses, both at home and in industries.

Photovoltaic solar panels

In this post we are going to tell you everything you need to know about  photovoltaic solar installations .

What are solar panels and how do they work?

The  operation of solar panels  can seem complicated . However, solar panels  are nothing more than devices made up of photovoltaic cells, whose main function is to transform solar energy into electrical energy. The operation is as follows : photovoltaic cells capture photons from the sun and thanks to  the semiconductor material  of which they are made,  silicon , they  transform photons into electrons .

The current generated by the solar panels is continuous, so it has to be transformed into alternating current through a  solar inverter , since most of the energy consumed on a day-to-day basis is alternating.

What is a solar panel made of?

In addition to photovoltaic cells, solar panels are made up of:

  • The electrical connection between cells
  • Encapsulants, which are usually EVA – ethylene vinyl acetate. This forms a sealing layer around the solar panels. It is very important, as it protects the photovoltaic cells.
  • Tempered glass or crystal, which together with the encapsulant, protects the photovoltaic cells.
  • PVC sticker, which is located on the back of the solar panels.
  • Aluminum frame with fixing hole

In addition to the elements that make up a  solar panel  itself, a photovoltaic system is also made up of the structure where the modules are attached, the wiring, the inverter that transforms direct current into alternating current and, if applicable,  batteries for solar panels. .

The main types of photovoltaic solar panels

Solar panels are of various types . In principle, a distinction is made between:

  • Monocrystalline
  • Polycrystalline
  • Amorphous

Of all  the types of photovoltaic solar panels , the  highest quality modules are the monocrystalline ones . These are made up of cells composed of a single silicon crystal, which offers greater efficiency. On the other hand, amorphous ones are the least recommended, since the technology they use is obsolete and the performance of the plates is inferior.

Monocrystalline solar panels

The  monocrystalline solar cells  are those cells that form consist of a single crystal of high purity silicon and solidified homogeneous temperature, which provides greater efficiency and performance of the panel as it allows electrons to move more Liberty.

Polycrystalline solar panels

On the other hand,  polycrystalline solar panels  are those composed of differently oriented crystals and are distinguished by their bluish tone. Although its manufacturing process is cheaper, its composition has a negative impact on its efficiency and performance.

What is the difference between monocrystalline and polycrystalline?

Monocrystalline modules have a higher degree of efficiency  (around 10% more), and better performance with both direct and diffuse irradiation, which generates a clear advantage on cloudy days.

Although the difference is clear at low temperatures, in that  monocrystalline panels perform much better than polycrystalline panels , they have very similar behaviors at high temperatures.

At  a residential level, you should always bet on monocrystalline technology , since space is limited and we can install more power with the same number of panels and because of the aesthetic effect, since  the monocrystalline cells are entirely black  and are better visually integrated into the roofs. .

Other types of solar panels

In addition to the classic modules, there are less common modules, at least today, such as transparent modules or those that work at night .

Transparent solar panels or photovoltaic glass

Transparent modules  have not been designed to replace photovoltaic solar panels, but they are a  complement to take advantage of solar energy even more .

They can be applied to windows, both in buildings and in vehicles, mobile phones or even urban furniture.

It is true that they do not reach 5% efficiency, but there is still much to do since the potential of this technology could reach unsuspected levels, reaching 100% of energy demand if we combine it with the solar panels that we currently know and we install on the roofs of our homes.

Although  transparent solar panels  do not reach the efficiency achieved by solar panels that we find in the current market, the union of both technologies will produce a greater amount of efficient electricity.

Solar panels that work at night

Of the latest in solar energy, but still to be developed and like photovoltaic glass, they come as a support to the classic solar panels, it is worth highlighting  the modules that work at night .

These modules take advantage of the heat that the ground gives off at night, converting it into energy. The creators of the technology have shown that the plates are capable of making an LED work with the energy produced.

Manufacturers

There are a multitude of  solar panel manufacturers  worldwide. At Otovo we bet on 3 main brands:

  • SunPower
  • JA Solar
  • FuturaSun

Why did we choose to work with these brands?

  • They are companies with a long history and experience
  • They use top quality materials
  • They constantly innovate
  • They bet on sustainability

The dimensions of the solar panels

Returning to the modules that are most useful,  one aspect that must be taken into account is their size.

The size of the solar panels  is determined by the number of cells that make up the panel. In this sense, the most common in residential use are  60 cells , arranged in 6 rows of 10 cells. This type of solar panels have a size of  164cm x 99cm .

On the other hand, those for industrial use have  72 photovoltaic cells , which raises the size of the solar panels to almost  2 meters x 1 meter . In addition, although less common, there are also solar panels with  more than 72 cells .

The difference in size between a panel for residential use and one for industrial use is given by the power required in each case. Well, an industrial warehouse will need a greater amount of energy to consume itself than a single-family home, and it allows working with larger panels. For residential use the optimal and recommended size is 60 cells.

Power and performance

Other important aspects that differentiate one solar module from another are their power and performance. The power and performance of photovoltaic solar panels  are determined by:

  • The type of cells
  • The number of cells that make up the module
  • Solar radiation and the climate of the area where the system is installed.

Although  the  performance of a solar  panel depends on all these elements, the key element in electrical power are the photovoltaic cells.

A photovoltaic cell can produce between 0.5 and 0.6 volts. To determine the power of a panel, you only have to multiply the number of cells with the power of each one.

If on average they produce, say 0.6 volts per cell,  the electrical power of a 60 cell solar panel will be 36 volts .

At Otovo we work with  solar panels of 340W and 400W . Although we  recommend the use of the most powerful panels  for greater long-term profitability, we install the 340W panels to any customer who wishes.

How to know how many solar panels you need

To know  how many solar panels you need, it  is enough to know the electricity consumption of your home and cross it with the power of the solar panels.

If we do the exercise for a bill of € 100 per month and a solar panel with a good production capacity, we find:

One module  is capable of producing up to 500W. A bill of approximately € 100 per month translates into an average of 5,000W. Therefore,  if your bill is around € 100 per month , it is most likely that  the ideal size of your installation is 10 photovoltaic modules . This is still a very rough estimate. For a professional installation, it is necessary to study your bill and size according to your actual consumption. In the case in which  the installation is isolated, more boards will be needed  to be able to generate more energy that will be stored in the batteries to have an uninterrupted supply.

Does it make sense to mount more boards than necessary?

Not at all, regardless of whether or not you are connected to the grid,  the main idea is to save with a photovoltaic self-consumption system . In the case of isolated installations, the solar panels have to produce as much energy as the house will consume.

However, you have to think that much of the day energy consumption is minimal in a common single-family home and that the solar panels will be producing energy that will be stored in the batteries all this time, even on the days in which the home is switched off. is empty.

On the other hand, if the installation of solar panels is connected to the grid, although compensation can be obtained,  if the amount of surplus energy produced exceeds that consumed from the grid in price, it will not be compensated , resulting in a loss of production that  is injected into the electricity company network without any compensation .

If the photovoltaic system is oversized and not all the energy poured into the grid is compensated, amortizing the investment will require more time since the initial expense was higher and the surplus is less remunerated than self-consumption.

How to choose the right solar panels for your home

When  choosing  solar panels for your home,  you must take into account mainly:

  • the type of solar panels and their quality
  • the energy consumption of the home
  • the size of the modules.

As we mentioned before, the  solar panels with the highest performance are monoscrystalline ones . It is advisable to opt for these plates to guarantee the highest generation of electrical energy and thus a faster return on investment.

Regarding the dimension, if we talk  about installations in single-family homes , the solar panels that are recommended are those with  60 cells .

And finally, to know the  number of plates required , you have to know the consumption. As we have seen, a module is capable of producing up to 500W. Depending on the consumption, a number or another of modules will be needed.

The elements that make up a photovoltaic system

system of self-consumption solar panels  consists of:

  • Photovoltaic modules
  • The  structure for photovoltaic modules
  • Investor
  • Wiring
  • Batteries (optionally if you decide to disconnect from the electrical network).

How to install

Installing a specialized job and therefore it is essential to have a  certified installer who has experience in  how solar panels are installed .

Broadly speaking, the steps to follow in an installation of photovoltaic panels are:

  • Assemble the installation support structure
  • Fixing of the structure and panels
  • Connect to electric inverter

If we talk about the entire process of installing a self-consumption system in a home, mounting the solar panels is only a small part.

To  have a functional and legal photovoltaic installation, it  is necessary to comply with the following steps:

  • Obtain a technical report from the certified installer
  • Obtain all the necessary permits that we detail later
  • System installation
  • Legalization of the same.

Orientation and inclination

 

The  orientation and inclination of the solar panels  are key to generating energy.

The ideal orientation is towards the south , since it guarantees more hours of direct sunlight per day. By not being able to orient them to the south, a west or east orientation can also be assessed, adapting the inclination. What is not recommended under any circumstances is to orient the solar panels towards the north since the amount of sun that hits the surface of the modules will be less.

With regard to  the inclination of the same , this depends on the area of ​​the country. If we take an average, we can say that  the slope in Spain is 30º . However, in  the north of the country you can have slopes of 40º, while in the south, 20º .

The closer to the equator the facility is located, the fewer degrees of inclination will be required since the sun’s rays fall perpendicular to the earth.

The advantages of solar panels

The advantages of solar panels  are numerous, regardless of whether we are talking about solar gardens, industrial panels used in large warehouses, warehouses, factories, etc. or solar self-consumption.

Clean and renewable energy generated by the sun

One of the greatest advantages that affects all types of solar energy generation is that they help to take care of the environment. The  energy that solar panels produce is 100% clean . Climate change, the turning points that mark the present and the ecological transition that the times demand and that governments are trying to promote, invite this type of energy to take more prominence in the energy mix.

In addition, it must be taken into account that solar energy is a renewable source, since the sun will never run out, at least not in the next million years.

Savings and profitability generated

The profitability of solar panels  is determined by the price of the system, the aid that can be obtained and the amount of energy produced. In a country like Spain, with an average of 1,300 hours of sunshine a year, the potential for generating electricity is very high.

In addition, the central government and the various local administrations throughout the territory are promoting photovoltaic self-consumption by making available aid in the form of: reduction of personal income tax, IBI and ICIO rebates or other aid.

In addition, even without these aids, the profitability of solar panels is high due to the mere fact that the energy consumes itself. Companies or homes that choose to  consume themselves may notice a drop in the electricity bill of up to 50% . The saving is given by self-consumption of energy during the day. Compensation can also be obtained for surpluses discharged to the network, but as we have already said, this is not a business, but rather  an aid to the amortization of the investment .

Maintenance

Another advantage  is the low maintenance they require.

The  maintenance of solar panels  involves :

  • Cleaning the modules
  • Replacement of defective parts

The  cleaning of the plates is very easy  to perform and does not require specialized assistance. It is more than anything about having the surface of the cells clean so that they can capture the greatest amount of solar radiation. Normally cleaning with the hose is usually sufficient. If the accumulated dirt does not only disappear with water, you can use a soft sponge that does not scratch the surface of the plates.

Regarding the replacement of defective parts, if they are still under  warranty , they will be replaced free of charge.

In addition, at Otovo, if you opt for the option of renting solar panels, we take care of the replacement of defective parts that are out of warranty.

 

Rent with 0 initial investment!

Requirements

 

However, in order to benefit from solar panels and their advantages, homeowners must meet a series of requirements.

We mainly talk about 2 types of  requirements for the installation of photovoltaic panels :

  • Related to the cover where they will be installed
  • Requirements related to the legal part of the installation process

 

Requirements that you have to meet the cover

The cover where the modules will be installed must be in good condition. If it shows any damage, it is recommended that they be fixed before the installation is carried out. A poor condition of the cover can lead to deterioration during installation. Additionally, post-installation repair would involve dismantling the system and reassembling it.

Also related to the roof, as we have seen, its inclination and orientation are key, since they determine the performance and profitability of the photovoltaic system. For the same reason it is important to avoid shadows that may be on the modules.

Permits and legalization

But these are not the only requirements. You also have to obtain a series of  permits necessary for the installation of solar panels . We are talking about permits both before and after the work, in order to legalize it: installation design, access and connection permission, work license and taxes (ICIO and urban tax), prior administrative and construction authorization, environmental and utility authorization. public, end of work certificate.

Once the work is finished, the following procedures must be carried out: initial inspection and periodic inspections, registration of the self-consumption installation with Industry, access contract for the self-consumption installation, energy supply contract for auxiliary services, compensation contract surplus, representation contract.

If the installation is isolated, procedures such as the surplus compensation contract must not be carried out.

In addition, of course you have to have certified installers to be able to legalize the installation.

The insurance

If we talk about  insurance for solar panels , it is important to know that the situation is different if we talk about self-consumption or companies that are dedicated to the production of photovoltaic energy.

Energy companies can protect their systems with dedicated insurance.  These insurances usually protect against theft and robbery; fires, explosions or lightning; damage to facilities and electrical equipment or loss of profits or machinery breakdowns .

With regard to self-consumption systems, the plates are usually  protected by home insurance . However, the insurance company must be consulted to determine if they consider the system as container or content. If it is considered as a container, you just have to notify the company about the installation. On the contrary, if it is considered content, you must take out insurance for the content of the home.

Prices

 

The  price of a  monocrystalline photovoltaic module with PERC technology , like the ones we use at Otovo, can reach 200 euros. It also depends on the manufacturer of the solar panels. But, if we talk about  the prices of photovoltaic installations

The prices of our photovoltaic installations depend on the province where they will be carried out. Why? Because we have a wide network of solar panel installers and we work with  cost models . The proximity of the installers makes their prices the most competitive.

In addition, our installer comparator system assigns projects to the ideal installer in the area, which has led us to offer competitive prices, through work efficiency, nationwide. In no case does this compromise the quality of the installation, quite the contrary.

In addition, the  prices of solar panels for self-consumption  will vary depending on the number of modules needed and the Tax on Constructions, Installations and Works, which is usually around 2-3% of the value of the installation.

Let’s take Madrid as an example, where we have very competitive pricing models. Here the approximate prices of the solar panel installations are:

 

DIMENSION PRICE
5 modules € 2,900
10 modules € 4,500
15 modules € 5,900

The uses and applications

Modules are a very versatile energy solution. The  uses of solar panels  are multiple , from a multitude of uses in the home to public lighting or transport.

Solar panels are used mainly for:

  • Home appliances
  • Heating
  • Hot water
  • Air-conditioning
  • Pool
  • Thermostats
  • Lighting (public or private)
  • Electric cars or caravans
  • Planes
  • Boats
  • Irrigation
  • Mobile recharge or other similar devices
  • Textile industry
  • Elevators

… and others.

Conclution

The  solar panels  are a world unto itself. For all the uses that they can be given and all the advantages they can bring on a personal and global level, they are a great alternative to the old energy consumption. In addition, they are becoming more profitable every day, as technological advances increase their power generation capacity and authorities promote a transition to clean and renewable energy. Change begins with each one of us.