GIANT SUN FIELDS
The biggest feature that distinguishes solar energy from other sustainable energies is that it can deliver energy directly without any other processes, not via a generator as in wind turbines or dams. We call the condition that enables us to release electrical energy through the sun’s rays, a photovoltaic effect. The discovery of the photovoltaic effect occurred in 1839 when Becquerel realized that the voltage in chemical cells was affected by the light falling on the electrolyte. In solid bodies, G.W. Adams and R.E. Day were able to demonstrate this fact on Selenium crystals in 1876. Of course, at that time, usable efficient electric energy could not be produced from the sun yet. In 1914, 1% efficiency had just been reached. As a result of the studies carried out, in 1954, 6% efficiency was achieved by using silicon crystal. In this way, the first designs began to be seen in power systems that would be used to obtain the energy required for spacecraft. After the 1973 oil crisis, large companies also helped universities in the development of photovoltaic batteries with the will of the states, and finally, the efficiency reached 20%.
Let’s briefly summarize the working principles of photovoltaic batteries:
The tiny energy packs that make up the light we mentioned earlier, the photons, hit the surface of our solar cell and break the electrons from their orbits that are already weakly attached to it. In this way, a tiny electric current is generated. Contrary to popular belief, these batteries work more efficiently when they can get enough sunlight at low temperatures. Just like computer processors, they are made of inorganic semiconductor materials. Gallium arsenide and crystalline silicon are especially preferred. There are three main active ingredients as diodes, transistors, and thyristors. The intensity of the incoming sunlight, the sunshine duration, the angle of incidence of the sunlight, the optimum efficiency temperature, and the structure of the material used are among the most important parameters for photovoltaics to generate electrical current.