The idea of ​​energy from sunlight has long tempted scientists. It is also implemented by Poles

Photovoltaic panels began to appear in the landscape of Polish cities and towns several years ago, so you might think that it is a new technology. This is not the case. What is new is the popularization of the use – today the panels are installed even on balconies in multi-family houses, although until recently it seemed that such a small installation would be unprofitable. The idea that sunlight can produce energy was clarified much earlier.

Scientists have been researching how to obtain energy from the sun for decades

In 1876, William Grylls Adams and his student, Richard Evans Day, discovered that an electrical impulse could be generated when selenium materials were exposed to light. Selenium solar cells couldn’t convert enough light into enough energy to power an electrical device, but it was proven that the solid material could turn light into electricity without heat or motion. This was the first step to further research.

It can be said that Albert Einstein was involved in photovoltaics. In 1904, he published a paper in which he described the photoelectric effect. In 1918, the brilliant but forgotten Polish scientist Jan Czochralski described a method of producing monocrystalline silicon, which enabled the production of monocrystalline solar cells.

In the 1960s, the use of solar cells in space flourished due to NASA space expeditions. However, in the 1970s, the costs of producing panels dropped so much that they could be used to power lighthouses, railway crossings and other buildings that were located far from population centers and connecting them to the grid was too expensive. In turn, in the 1980s, the use of solar cells became popular: many readers remember calculators in which there was no need to insert batteries because they were charged by sunlight. This is photovoltaics, although on a very small scale!

The 1990s brought the commercialization of technology. The first grid-connected and free-standing installations were built, and the governments of several countries began to subsidize photovoltaic investments. At the end of the last century, the world leader in PV installations was the United States, followed by Japan and Western European countries. At that time, China was not interested in photovoltaics, but 20 years were enough for the Middle Kingdom to be responsible for half of the installed capacity in the world!

Photovoltaics. China has left the rest of the world behind

China is currently the undisputed leader in global photovoltaics. At the end of 2021, they had photovoltaic installations with a total capacity of 323 GW, which satisfied approximately 4.8-6%. total energy consumption in the country. They were also the record holder in terms of connection capacity year-on-year with an increase of 53.9 GW. China is expanding energy storage facilities, but also wants to reduce the unit cost of energy storage by 30%. by 2025 and create a system that will be profitable without subsidies.

In 2021, photovoltaic installations in the United States produced 120 GW of energy, giving the country second place among the global photovoltaic leaders. Just a decade earlier, the country had just over 4 GW of solar installations! It is estimated that a quarter of a million people work in jobs related to photovoltaics.

In the first half of 2022, the US solar market accounted for approximately 4.5%. national energy mix. The American legislator wants to encourage an increase in the number of installations and has introduced a 10-year tax relief for investments for this purpose. It is expected that by 2027 the total installation capacity may increase up to 335 GW.

With 74.19 GW in 2021, Japan ranks third in solar energy production. The example of Japan is interesting because it is a country with a very dense development, where land is a scarce commodity. To place panels, Japan uses, among others, floating platforms and abandoned golf courses, which are remnants of the boom in this sport from the 1980s. Interest in solar energy increased in Japan after the nuclear power plant disaster in Fukushima in 2011, when the authorities decided that it was necessary to develop energy sources that would the world will simply be safer.

Germany was just behind the podium – in 2021 it had photovoltaic installations with a total capacity of 59 GW. As much as 41.1 percent the energy there comes from renewable sources. The German government sets a goal for the total capacity of photovoltaic power plants to reach 215 GW by the end of 2030.

Poland: photovoltaics is developing dynamically, but not without obstacles

And where does Poland rank in this context? The report of the European photovoltaic industry association SolarPower Europe (SPE) confirms that our country is in eighth place, ahead of, among others, Australia or the Netherlands. In 2022, the capacity of photovoltaic power plants in Poland increased by 4.5 GW. The growth rate has slowed in 2023 and there is a risk that we will fall out of the top ten largest photovoltaic markets in the world. The increase in the number of home PV installations was slowed down by changes in the prosumer billing rules, which were introduced in Poland in April 2022. However, the prospects for investing in ground-mounted PV power plants are promising: however, changes in spatial planning regulations that may affect developers of PV farms in Poland may become a challenge.

Scientific teams around the world are working to make the production of photovoltaic panels as cheap and environmentally friendly as possible, as well as to extend the life of the panels. The average lifespan of panels is estimated at 25 years – and the weakest ones stop working effectively after 15 years and no longer fulfill their role. The panels are constantly exposed to unfavorable weather conditions: snow, rain, wind and intense sun. Their recycling is still in its infancy, but in Poland you can already find plants accepting used photovoltaic panels. The use of the elements that make up the panel will reduce production costs and the costs incurred by the environment – because if we think of photovoltaics as environmentally friendly energy, it must cover the entire life cycle of the panels.

Polish scientists are also working on improving photovoltaic panels and various aspects of obtaining, storing and using energy from the sun.

Warsaw University of Technology: scientists are working on increasing the efficiency of energy production

Only a small part of the solar radiation falling on the photovoltaic cells produces energy. The rest of the energy is lost, mainly as heat. Scientists from the Warsaw University of Technology are working on a material with a negative refractive index, which will not only reduce the heating of the cell, but will also increase the efficiency of energy production.

Scientists have observed that a properly designed hyperbolic metamaterial can act as an edge filter for a photovoltaic cell that reflects infrared radiation. This leads to heating of the cell and, consequently, to a decrease in its energy efficiency.

– In our project, we perform both a full simulation of the electrical and optical parameters and experimentally verify this assumption – said Dr. Eng. Bartosz Fetliński from the Faculty of Electronics and Information Technology, head of the research team, quoted by the Warsaw University of Technology. – We are creating a hyperbolic metamaterial structure composed of ultrathin layers, nanometers thick. The structure created in this way will allow, among others, to obtain filters with a very sharp edge, filtering very well and having the ability to achieve a sudden transition from transmission to absorption or reflection – he emphasized.

It is these features of hyperbolic metamaterials that have led scientists to use them in photovoltaic panels.

– Hyperbolic metamaterials have not been used in this way so far, so our project is characterized by high scientific innovation – added Dr. Fetliński. – Therefore, there are no reliable characteristics of these materials in the literature that could be used in our project. It happens that properties are described when one layering method is used, but there is no description when another is used.

Experimental verification of the modeled metamaterial structures is carried out in cooperation with the Institute of Microelectronics and Photonics of the Łukasiewicz Research Network (IMiF) and the Institute of Physics of the Polish Academy of Sciences (IFPAN).

University of Rzeszów and Rzeszów University of Technology: extension of panel operation

Scientists from the University of Rzeszów and the Rzeszów University of Technology have developed a coating that extends the operation of photovoltaic panels

According to the leader of the scientific team, Dr. hab. Małgorzata Pociask–Biały, as part of the project, researchers want to use a multi-layer polymer coating with air bubbles enclosed between two layers of foil with the characteristics of micro concentrators of solar radiation.

– Although the thickness of this layer does not exceed 30 μm, it will be a durable coating whose transmittance will correspond to a filter composed of a system of air microlenses closed between polymers – foils during the process of applying them to glass or transparent polymer – explained in May, quoted by PAP, Dr. Pociask-White.

The result of the work of Podkarpacie scientists is a coating that will enable photovoltaic modules to operate longer. Such a system can be used, among others, in ground systems producing electricity to power electric car batteries, emergency power supply for aircraft cockpits, systems e.g. analyzing the composition of the atmosphere at various heights above the Earth’s surface or other systems placed in space.

The project of scientists from received nearly PLN 200,000. co-financing under the grant program of the Podkarpackie Innovation Center.

Perovskite solar cell factory

In 2021, the world’s first perovskite solar cell factory was established in Wrocław. Perovskites are materials that conduct electricity and absorb light. For this reason, photovoltaic manufacturers aimed to use these raw materials during production. The problem was low efficiency and high costs.

Polish technologist Olga Malinkiewicz, founder of Saule Technologies, coped with this task. The world’s first perovskite-based solar cells will be produced in the company’s factory in Wrocław. Thanks to the discovery of the Malinkiewicz team, they managed to create materials at much lower costs.

Perovskite-based solar cells will be produced at the Saule Technologies factory in Wrocław. According to experts, the possibilities of using these materials are basically unlimited: they can be used, for example, in construction and in the production of mobile phones.

On November 11 this year, 28 perovskite cells used in the Polish observation satellite STORK-7 were launched into space on the Falcon 9 rocket. Olga Malinkiewicz argues that perovskites are an ideal power source in space due to the fact that they are much lighter than traditional cells. and flexible, so they can be packed into a small space, and due to the possibility of digital printing, they can take any shape. The mission is the first-ever test of this type of cells in space.