Almost everyone has probably seen them on someone’s roof: solar panels. But what are solar panels and what do they do exactly?
WHICH ARE THE SOLAR PANELS?
Solar panels are devices designed to take advantage of sunlight and turn it into electricity, hot water or heating.
There are the:
- Paneless solar photovoltaic, responsible for generating electricity using photovoltaic solar cells and photons or light rays from the sun.
- Solar thermal panels or collectors, responsible for producing hot water for sanitary use (showers, wash dishes ect)
What are photovoltaic solar panels?
A solar panel or photovoltaic panel (from the English ‘Photo-Voltaic’) is a panel that converts solar energy into electricity that is obtained in a sustainable way.
Photovoltaic solar panels use sunlight or daylight to create direct current voltage. This becomes alternating voltage, which is also called “current”.
Formats of solar panels
In practice, a standard format has been created for panels with an area of 60 square solar cells of 156 x 156 mm each. This corresponds to a size of 1.00 x 1.60 meters per panel. The surface area per panel thus reaches an average of 1.6 m2.
Please note Do not confuse a solar panel with a solar collector.
In short, it works like this: as soon as light falls on a solar cell, an electrical voltage is created between two layers of the solar cell. This voltage is collected and sent to an inverter , which converts it into usable energy that is sent to the meter box.
However, you should not confuse a solar panel with a solar collector. A solar collector is intended to heat a liquid (usually water with antifreeze). With the heated water from the solar collector, a solar water heater can heat the water for domestic use.
This means that almost half of all the hot water used in the home can be heated with a solar water heater. This saves you € 80 on your energy bill on an annual basis.
Solar panels are usually on the roof and have to last a long time. The useful life of solar panels is 25 years or more. They have difficulties with high and low temperatures, wind and rain, snow and ice.
They must be able to withstand hail and dirt from birds and air pollution should be washed automatically.
Learn how photovoltaic solar panels work
¿ What are solar thermal panels or solar collectors?
The collectors are systems designed to absorb solar light and transform it into heat. This heat can be used to heat the sanitary water in the bathroom, shower and kitchen, to heat your home or to heat your pool. Then we talk about solar thermal energy or solar heat . And those ‘solar panels’ that belong to a solar boiler are called solar thermal collectors.
Each system naturally has its own advantages. And, of course, both systems can be combined, although Belsolar, the sectorial association of manufacturers and distributors of solar boilers, points out that all studies and possible simulations show that a solar boiler, with solar thermal collectors, is a much more sensible option and profitable.
History of solar panels
Before telling you more about the different types of solar panels , we remember the moment when everything began. We take you to France in the year 1839.
The concept of converting solar energy into electricity has existed since 1839. The French physicist Antoine César Becquerel discovered the photovoltaic effect. 50 years later the first solar cell could be made.
Of course, solar cells at that time were not as powerful as they are now, because they could only convert 1 to 2 percent of sunlight into electricity.
Only decades later, solar panels could be produced that provide sufficient performance for normal private users.
However, we can still find the basis that the French physicist then set in modern solar panels.
Characteristics of a solar panel
What makes a solar panel a solar panel? And how is a solar panel built? In order to give a correct answer to these questions, it is necessary to expand a bit the characteristics of a solar panel.
In practice, solar panels have a standard surface area of approximately 1.6 square meters and consist of 60 (6 × 10) 156 mm square solar cells per side. These solar cells are collectively called “module”.
The power of each module is determined by the power of the direct current (DC output power) under standard test conditions. The output power of DC varies in most cases between 100 and 365 watts. The efficiency of a module determines the size of a module of the desired electrical power.
More simply, this means that, for example, a 230-watt module with 8% efficiency will have twice the surface area of a 230-watt module with 16% efficiency.
The result is that they have different returns and they also differ in price. The unique glass panel has the highest efficiency and the highest price. Then the polycrystalline panel and then the thin film solar panel.
The efficiency of a solar panel
The so-called “energy conversion efficiency” of a solar cell is the percentage of solar energy that can be converted into electrical energy. Today, this percentage is on average between 15 and 18 percent for a commercial solar panel.
However, the technology of solar panels does not stop. Scientists are extensively tested to further improve efficiency. For example, the efficiency percentages of more than 30 percent are already being achieved today!
What are solar panels for the environment?
Solar panels convert sunlight directly into electricity and do not cause air pollution or greenhouse gases. Therefore, they are one of the cleanest forms of energy.
The environment is also taken into account when producing solar panels. In addition, the solar panels are silent and discreet. As far as we are concerned, there are really only benefits for solar panels.