What is PtX?
PtX is the abbreviation for Power-to-X, which is a process to convert electricity into another form of energy (X). It is one of the technical solutions that contribute to green transition by storing renewable energy and balancing the consumption and production of energy.
Power-to-X (PtX, also abbreviated P2X) is a collective term that describes the process of converting electrical energy into another form of energy. Power-to-X exists in many variants, but one of the most described and used methods in efforts to store green energy is conversion to hydrogen by splitting water into hydrogen and oxygen.
Power-to-X is the path to a greener future
Power-to-X is a solution that can help phase out black energy from fossil fuels such as oil, coal, and natural gas, and is one of the technical conversion paths for storing green energy. Extraction of green energy comes, among other things, from renewable energy sources such as wind turbines and solar cells, which depend on the weather to produce electricity.
This has the popular consequence that we have too little electricity to meet the demand from industry and households when the wind does not blow and the sun does not shine. Conversely, we often have more electricity than we can consume when the wind turbines rotate at high wind speeds and when the solar cells are heated by the sun’s rays.
Storage of renewable energy is ensured with Power-to-X
To make us less dependent on weather conditions, we need a way to store the green electricity. Storage can help balance production and demand so that excess green energy from renewable energy sources is not lost. This can be done, for example, with Power-to-X, where one of the methods used is to apply electricity to water molecules. The method is called electrolysis.
Hans Buch helps customers with instrumentation for PtX application
There are a number of challenges in building, operating, and maintaining that ensure the best possible uptime of a Power-to-X plant. Hans Buch provided technical sparring and delivered instrumentation in the form of humidity and temperature meters, as well as dew point meters for the customer’s PtX application.
Read more: “Customer case: Instrumentation for PtX application“
What is electrolysis?
Electrolysis is a way to separate a substance using electricity. By applying direct current (DC) to a container with liquid, two energy charges are brought into contact with the liquid. These energy charges are referred to as a plus and a minus connection, also called a positive and negative connection. The positive connection (+) is called a cathode, while the negative connection is called an anode (-).
There are different technological methods to perform electrolysis, such as Alkaline, PEM (Proton Exchange Membrane), and Solid Oxide Electrolysis, as well as variants that combine or are based on the mentioned technologies.
Positively and negatively charged ions determine separation in electrolysis
Thus, ions in the form of atoms and molecules will be attracted to either the cathode or the anode when exposed to electricity. It depends on whether the atom or molecule has gained or lost electrons. If electrons have been lost, the atom or molecule will be a positively charged ion (cation), while an atom or molecule that has gained electrons will be a negatively charged ion (anion).
Electrolysis splits water and separates hydrogen and oxygen
Electrolysis is increasingly used to store energy. By using electricity from renewable energy sources, energy storage is ensured, which could otherwise be lost. A common method is to split water (H2O) into hydrogen (H2, hydrogen) and oxygen (O, oxygen -> O2). By applying electricity to the water molecule, the oxygen will seek the anode (-), while the hydrogen will seek the cathode (+). In this way, the
What forms of Power-to-X (PtX) exist?
Power-to-X is also popularly called Power-to-Everything. This knowledge article focuses on the conversion of green electricity produced from, for example, wind turbines and solar cells to hydrogen, but Power-to-X covers a wider range of end products, which can be other than pure hydrogen – for example, methanol or ammonia.
In a chemical process where hydrogen is combined with, for example, CO2, different forms of energy can be created that may be suitable for fuel (so-called electrofuels) for heavy transport on roads, ships, and airplanes. The list below provides a larger selection of technologies with PtX-related abbreviations:
- PtX: Power-to-X (Power to Everything, also abbreviated P2X)
- PtG: Power-to-Gas (also abbreviated P2G)
- PtS: Power-to-Syngas (also abbreviated P2S)
- PtL: Power-to-Liquid (also abbreviated P2L)
- PtH: Power-to-Heat (also abbreviated P2H)
- PtF: Power-to-Fuel (also abbreviated P2F)
- PtC: Power-to-Chemicals (also abbreviated P2C)
Sources
- DTU – Technical University of Denmark: “Power-to-X – from green electricity to green fuels”:
https://baeredygtighed.dtu.dk/teknologi/power-to-x - AAU – Aalborg University: “Power-to-X Technology: Overview, possibilities and challenges” (2022, Simon Araya, Samuel; Cui, Xiaoti; Li, Na; Liso, Vincenzo; Sahlin, Simon Lennart):
https://vbn.aau.dk/files/514146100/PtX_Report.pdf - Danish Energy Agency: “What is Power-to-X?”:
https://ens.dk/ansvarsomraader/power-x-og-groen-brint/hvad-er-power-x - Ramboll: “Power-to-X: paving the way for a greener future”:
https://www.ramboll.com/net-zero-explorers/power-to-x-explained - Hydrogen Denmark: “About hydrogen”:
https://brintbranchen.dk/om-brint-2/
