Silicon photovoltaic cells dominate the solar energy market, although there are alternative technologies that use organic materials -as an ingredient in tofu and bath salts- They have been trying to unseat them for many years. A study published last Monday in the journal Natural Energy He proposes a solution to one of the main problems in solar energy, efficiency (that is, the waste of a lot of natural light in current systems), and suggests that more efficient silicon panels may be on the way. Kunta Yoshikawa, an expert in the area, has presented the first cell made with this material that exceeds 26% efficiency to convert sunlight into electricity, which represents a 2,7% improvement in photoconversion compared to the previous record (25,6%).
To achieve this amazing result, Yoshikawa and his team have developed a structure based on heterojunction -a structure made up of two layers- of monocrystalline silicon with a top layer of amorphous silicon, a design that simultaneously increases the capture of sunlight and its conversion into electrical energy.
The essential properties of the device such as service life, series resistance and optical properties must be simultaneously improved to reduce light waste. Implementing that technology can lead to energy efficiency of 29% in the coming years, the study authors write.
MIT also made public in 2016 the creation of a solar panel capable of generating 20 times more energy than traditional devices. Those cells have a more intelligent, according to the description published in the magazine Energy and Environmental Science: they are vertical and move from one side to the other to follow the movement of the sun from its appearance on the horizon until dusk.
Julio Amador Guerra, director of the master's degree in Renewable Energies and the Environment at the Polytechnic University of Madrid, explains that the increased efficiency of solar cells makes them increasingly competitive with conventional energy sources. "The new designs allow to have more power for the same surface occupied by the photovoltaic modulesIn other words, it is possible to obtain more solar energy per surface area, which implies a decrease in the cost of this technology. A consumer can have more power and energy without paying more for the support structure of the modules or for the electrical installation ”, he says.
Guerra is committed to continuing to develop photovoltaic solar energy with “all possible materials” —crystalline silicon, mechanical fluids, organic and inorganic cells—, but points out that research and technological advances should be accompanied by political advances. "Legal obstacles to the consumption of these energies must be eliminated”, He maintains. The Spanish Government approved, in 2015, the so-called sun tax, which taxes the self-consumption of energy produced by solar panels. “We must establish mechanisms that allow renewable energies to compete on equal terms with the rest of conventional energy technologies, taking into account all the environmental impacts ”, defends the expert.
Brussels charges against Spain
Brussels has been the last to charge against the multiple obstacles that the Government of Spain tries to impose on self-consumption electric in our country. The European Commission has sent a tough letter to the Ministry of Energy and Industry, currently headed by Álvaro Nadal, to understand the reasons behind the administrative obstacles imposed by the portfolio.
In this letter, to which El Periódico de la Energía has had access, Brussels is against the application of the energy regulations being carried out by the Government. That is, to the series of requirements that an individual must meet in order to be able to self-supply energy.
The Commission has initiated contacts with the Spanish authorities in order to clarify the reasons for which this procedure was introduced ”, has assured Paula Abreu, Head of Renewable Energies in the Directorate General of Energy of the European Commission. The Head of Renewable Energies in the Directorate General of Energy of the European Commission, Paula Abreu, has stated this in a letter sent to the Holtrop office, which advises the Platform for a New Energy Model, the organization that denounced the self-consumption regulations to Brussels.
In this sense, the European Commission has drawn attention to Spain for a few obstacles to the rights of Europeans and has given examples to Spain to correctly update the regulations on self-consumption. Thus, it asks the Government to simplify administrative procedures
The European directive requires simplifying procedures and gives examples to Spain, while Rajoy insists on maintaining the current electrical system based on tax collection criteria. The measure would cost less to the public coffers than the early retirement of 20% of the stevedoring workers.