Power-to-gas makes it possible to store energy for a long time. However, the technology is only ecologically sensible under certain conditions. Power-to-gas is one of the so-called “Power-to-X” technologies. It is essentially February 2019 Calendar Editable about the fact that electrical energy (power) is converted into another type of energy or energy carrier (X). In the case of power-to-gas, electricity is used to generate fuel gases, which can then, for example, drive means of transport.
February 2019 Calendar Editable
The idea of converting electrical energy into gas already existed in the 19th century. But it was only in recent years that the energy revolution started to explore technology on a grand scale. After all, you can only switch to electricity from renewable sources, if the electricity can also be stored.Thus, Power-to-GasSimplified representation of the electrolysisSimplified
representation of the electrolysis (Photo: Utopia / Leonie Barghorn) The power-to-gas process consists of two steps: 1. First of all, water is split into electricity by hydrogen and oxygen (see the graph on the right). The process is called electrolysis and runs like this: Two electrodes are immersed in a water basin and then energized. Because of the voltage, one electrode is positive and
the other is negatively charged. When the voltage is high enough, the water molecules split into negatively charged oxygen ions (O2-) and positively charged hydrogen ions (H +). These are in each case attracted by the oppositely charged electrode. Finally, a charge equalization takes place at the electrodes: The positively charged hydrogen ions take up one electron each from the
negatively charged electrode and can thereby form hydrogen molecules (H2). On the other hand, the oxygen ions release their excess electrons to the positively charged electrode and oxygen molecules (O2) are formed. Because hydrogen and oxygen are gaseous, they rise to the top. The hydrogen can now in principle be fed into the natural gas grid or otherwise reused.
Free Editable February 2019 Calendar Template Download
However, too much hydrogen can damage the network. In addition, hydrogen is very explosive – maybe you know the so-called oxyhydrogen reaction. Therefore, methane is often produced from the recovered hydrogen.2. When hydrogen and carbon dioxide are exposed to high pressure, they react to form methane and water. This artificially produced methane can be more
easily fed into the natural gas grid.3. The gas can either be used directly as a vehicle drive, in the chemical industry or in gas-fired power plants to generate electricity. Power-to-gas: currently still too low efficiency Power can now be used to store large amounts of electricity in Germany With power-to-gas, large amounts of electricity can already be stored in Germany.
Photo: CC0 / Pixabay / Free-Photos) Power-to-gas is one of the few technologies that makes it possible to store electricity in the long term. Unfortunately, its impact grad at the moment still very low. According to a report prepared by the Fraunhofer Institute for Wind Energy and Energy System Technology.
(IWES) in 2011, it is only about 40 percent. Using other storage options or using the electricity directly is more ecologically sensible. There are, however, several ways to increase February 2019 Calendar Editable the efficiency: both in the electrolysis and in the production of methane produces heat. If this is used further, the efficiency increases to up to 60 percent.