How does solar energy work?
There are two main ways to use solar energy, as a heat source for solar thermal systems, the other as a source of electricity for solar photovoltaics systems. We will focus on the latter application.
In principle the way in which to convert sunlight is captured in power is via solar or photovoltaic panels. These panels are comprised of groups of calls cells or solar cells that are responsible for transforming the light energy (photons) into electrical energy (electrons).
These cells are connected together as a series circuit in order to increase the output voltage of electricity, or whether it will be 12 or 24 volts while several networks are connected parallel circuit to increase power generation capacity to may provide the panel.
As the electric current type provided by solar panels is direct current, often an investor and / or power converter is used to convert the direct current into alternating current, which is what we usually use in our homes, jobs and businesses.
When we speak in Erenovable new discoveries or advances in science we usually are referring to the discovery or development of new and better materials for manufacturing a solar cell.
A solar cell operates basically as follows: the photons coming from the sun radiation, impact the surface of the cell, where they are absorbed into semiconductor materials such as silicon. Photons hitting the freeing electrons from the atoms to which they belonged. So the electrons begin to flow through the material and thus produce electricity.
This basic operation is repeated whatever the material used in the solar cell, provided of course have conductive properties and light absorbing.
Solar cells that make solar panels currently available on the market are made from silicon, abundant on the planet semiconductor material, but also difficult to extract and synthesize, thereby resulting solar panels are often expensive, heavy and difficult installing.
For this reason scientists worldwide work continuously to find new materials that result in solar panels cheaper, efficient, lightweight, thin and able to have as many applications as to be able to be packaged in a spray.
So we can see that working in the manufacture of solar cells with materials like copper, indium, gallium and selenium to germanium. The latter gives the best results in efficiency but are expensive to manufacture, so that its use is restricted to entities such as NASA. Calls double or triple junction cells, using various additions, thin-film technology with use of dye-sensitized solar cell or Graetzel, hybrid materials, and nanotechnology are also performed.
The present and future solar energy
The great challenge of the future is on organic solar cells , which are cells that are made based on organic polymers, such as certain types of plastic, which has the same conduction properties than silicon but can be “printed” or ” paid “on almost any type of material.
Compounds for organic solar cells are cheaper to manufacture, lighter and easier to install. The big disadvantage of is that have not yet reached the level of conversion efficiency with silicon panels. Although we continually see that scientists can increase this level of efficiency, yet this happens in controlled laboratory settings and still lacks enough to reach shopping destination.