GreenTV presents interesting projects, innovative technologies and current events from the world of science and business.
Even better than the previous champion gallium arsenide, which in turn is much better than the most popular silicon. Thanks to that, they can absorb light in ultrathin layers. This reduces the intake of material needed to produce such a cell by at least three times. Theoretically, the resources are unlimited as this material is produced from very cheap base materials in the process of chemical synthesis. Additionally, it is very practical that the cells can be produced in the process of wet chemistry. It means, for example, that such perovskite can be simply printed.
Perovskites are materials with a specific layout of their crystal lattice. Their properties are not determined by their composition but by the way their atoms are arranged. They owe their name to a Russian geologist Lev Perovski whose friend, a German Gustav Rose, as the first one classified this arrangement of calcium titanate atoms which can be found in rocks of the Ural Mountains. It took place over a century ago and since then, everything that has the same arrangement of atoms as calcium titanate is called a perovskite. It is easy to guess that there are plenty of various types of perovskites. Some of them occur in nature (e.g. in rocks, magma), others can be produced in laboratories in the process of chemical synthesis. The so called hybrid perovskites are the most interesting. It means that they are partially an organic and partially non-organic material. In nature such fusion is very rare but it gives unique properties.
After just several years of using perovskite in photovoltaic cells, their laboratory efficiency became virtually comparable to the most advanced photovoltaic technologies like, for example, crystalline silicon, CdTe and CIGS, and now it reaches the level of about 20%. However, it must be pointed out that cells based on perovskite constitute a totally different approach to photovoltaics. These cells cannot be compared to silicon cells. It is like comparing electric vehicles to the first steam driven automobiles. Both have 4 wheels, steering wheel, and they can run, but the difference is made by their effectiveness of work, easy operation and grace.
Instead of crudely looking structures holding rigid silicon panels, which often ruin an aesthetic image of beautifully designed buildings, we will use perovskite cells that do not have negative effect on architecture and fit into it instead. Thanks to the unique features of perovskites it will be possible – and it is a perfect example of a non-invasive implementation of this technology – to merge photovoltaic cells with windowpanes. Windows change into photovoltaic panels while they transparency almost stays the same. Thanks to flexibility of perovskites also roof tiles will be covered with perovskite cells and, as a result, the entire roof will become a photovoltaic panel, which externally will not differ from a roof covered with normal roof tiles. Perovskites can be laid on entire facades of modern buildings or production halls, so that not only the roof and windows, but also walls would generate electricity. Just compare the roof surface (which presently is the maximum surface of silicon cells) with the surface of walls of a skyscraper.
That is not all. Thanks to unique properties of perovskites: flexibility, transparency and a very low weight, if the technology evolves, each of us will have several devices or items integrated with perovskites. Tablet screen covered with perovskites will not look different than today but it will help charging a battery. When going on distant trips, even to the wilderness, we will not be concerned about the battery level – the entire tent can function as a one large photovoltaic panel generating electricity. The panel could be rolled up and put into a rucksack when going into the mountains. The more electric devices we use, the bigger the multitude of possibilities is. And as we know, their number constantly increases. Regardless of the perovskites integrated with consumer electronics, in time the need to supply devices classified as wearable technologies will increase (this trend is already very clear). Once again, thanks to the properties of perovskites, a photovoltaic cell will not be a classic panel, but simply a material generating electricity. Today we can imagine a shirt with insertions made of flexible perovskite.
The possibility to integrate perovskite cells with facade will create a passive (low-emissivity) building. Of course much will depend on a geographic location of the building. If an efficient energy storage system is ensured, then it is possible that there will be no need to connect it to power grid. This would mean the possibility of zero electricity bills or even – through connection to the smart grid (“intelligent” energy grid) – to sell the excess electricity. The cost of electricity would just mean the cost of perovskite cells purchase. In order to make all these scenarios reality, a significant improvement of cells is required. If the technology of perovskite cells reaches that stage, then it is easy to predict its impact on the energy market. So far a Polish physicist Olga Malinkiewicz began the technological race by developing a technology of low-temperature production of flexible photovoltaic cells based on perovskites. After the first year of her work on commercialisation of the technology, the Polish researcher has every reason to be proud of herself – a company Saule Technologies, founded by her, received over 20 million zlotys of subsidy from the National Research and Development Centre for further development of this technology, and also in September 2015 entered into agreement with a Japanese investor, Hideo Sawada.
Technologies has a great potential of revolutionizing the solar energy market and make it more accessible and common. The future applications of this technology are almost unlimited. We commit to this project with great satisfaction and, of course, we will support the company founded by Olga Malinkiewicz in its further works – Hideo Sawada says. The breakthrough technology of generating electricity from photovoltaic resources based on perovskite caught interest of army. The Inspectorate for Implementation of Innovative Defence Technologies identified number of potential implementations for the needs of the Polish Armed Forces. Presently, the directors of military equipment and the representatives of science and arms industry, through our activities, were acquainted with the possibilities of this technology and possible implementations after full technological product development is achieved. The army representatives regard the technology which is currently developed by Olga Malinkiewicz as highly prospective and game-changing. In future the success of perovskites can redefine the possibilities of military equipment in Armed Forces – says lieutenant colonel Rafal Miernik from the Inspectorate for Implementation of Innovative Defence Technologies. On his blog a politician Janusz Korwin Mikke is much less enthusiastic on the discovery of Olga Malinkiewicz. Among the many delightfully sarcastic comments, which are by the way based on Wikipedia (long live the Bible of the 21st Century!), we can read as follows: [...] the issue of this perovskite looks like the same kind of fraud as “N rays” or “cold fusion”. And certainly it is a symptom of decay of our civilisation. In a normal country, if somebody discovers something, then he/she gives the apron to the laboratory assistant, jumps into the cab and goes straight to the patent office. Next, he/she makes efforts to sell the invention. [...]
But if somebody starts with talking about it instead of acting, then something must be wrong. Olga received a „Photonics21” award from Neelie Kroes, former European Commissioner for Digital Agenda. Taking into account Kroes and her job, every capitalist with common sense knows that the likelihood that perovskite is of any worth is reduced by three times. And it should be indicated that Olga Malinkiewicz is the co-author of the patent: Inverted solar cell and process for producing the same: Inventors: O. Malinkiewicz, A. Soriano, H. J. Bolink, Md. K. Nazeeruddin, M. Graetzel. Request Number: EP13183813.8 Country of priority: Switzerland. Priority date: 2013. Titularity: Universidad de Valencia and École polytechnique fédérale de Lausanne (EPFL). Extended to: Europe. As you can see, Olga holds the patent, but she is not an autonomous inventor, what surely increases the company costs of using this patent. Therefore, all we can do is to cross our fingers for her success, especially given the fact that the competition never sleeps. Other scientists also work on perovskites, including a team from the Korean Research Institute of Chemical Technology (KRICT) supervised by Sag Il Seok, who is the inventor of world’s most efficient perovskite technology – the record confirmed by American NREL (US National Renewable Energy Laboratory), where the result of conversion efficiency reached 20,1 percent. Anyway, we cross our fingers for the Polish researcher and will keep a close eye on the development of this prospective technology.
Source: Green Economy