The latest episode of the popular series Nezkreslená věda focuses on a key topic of our time – the photovoltaic harnessing of the Sun's energy.
The reason for connecting the popular educational series with the Institute of Physics is the Pilatus project, in which Martin Ledinsky's team is involved. Scientists at the Institute of Physics aim at making the production of photovoltaic cells more efficient and are also investigating new materials, such as perovskites, which could replace or complement the traditional silicon used in solar panels.
The cartoon series first shows that global energy consumption is equivalent to about 20 terawatts (TW) of power – and most of the energy comes from the Sun (albeit indirectly, in the form of energy stored in fossil fuels). Yet the energy falling from the Sun to Earth amounts to a staggering 174,000 TW.
The story of photovoltaics also shows the importance of basic research. The photovoltaic phenomenon was discovered by Edmund Becquerel by happy accident in 1839, when he discovered that illuminated electrodes covered with silver bromide generate an electrical voltage and current. It was not until 114 years later that in Bell's laboratories the first solar cells with an efficiency of 6% were created.
But even these could not be used in practice yet because of their cost. Fortunately, solar power became essential to the space programme after the launch of Sputnik in 1957. The American satellite Vanguard transmitted signals for six years thanks to solar power.
Since then, photovoltaic cells have undergone developments that have made them more than 100 times cheaper. Photovoltaics have thus become the matchlessly cheapest source of electricity.
The Pilatus project aims to establish three pilot lines covering the entire production cycle of innovative solar panels, and thus bring PV production back to Europe. The use of special technology with contacts on the underside of the cells should not only increase their efficiency but also minimise the CO2 footprint of their production. "If we want to be competitive, we need to come up with a new, highly efficient technology that will make photovoltaics affordable while also meeting stringent environmental requirements." Martin Ledinský explains.
So far, solar energy accounts for only 1% of the world's energy mix, but this share is growing rapidly thanks to new technologies and materials, which are also being researched by scientists at the Institute of Physics. "In the future, we will consider 1957 the beginning of the solar age!" sums up Antonín Fejfar, the expert guarantor of this episode of Undistorted Science.
Nezkreslená věda is a popular educational series of the Czech Academy of Sciences, which was launched in 2014 and has since received numerous positive responses from educators, students and the general public. The commentary for the episode was narrated by Barbora Hrzánová and Radek Holub.