What does electrolyzer mean?
An electrolyzer is a device that uses electricity to drive a non-spontaneous chemical reaction, most notably splitting water (H₂O) into hydrogen and oxygen gases. It works by passing a direct current through an electrolyte — often a solution or membrane — so that reduction occurs at one electrode (producing hydrogen) and oxidation at the other (producing oxygen). Electrolyzers come in several main types, including alkaline and proton-exchange-membrane (PEM) designs. Once a fairly specialized piece of laboratory and industrial equipment, the word has gained prominence in recent years as governments and energy companies invest in 'green hydrogen,' produced by powering electrolyzers with renewable electricity rather than fossil fuels. In this context, the electrolyzer is widely regarded as a cornerstone technology for decarbonizing sectors such as heavy transport, steelmaking, and long-duration energy storage. The term is chiefly technical in register, appearing most often in scientific literature, engineering reports, and energy-policy discussions.
nounA device that uses electricity to split a substance, most commonly water, into its constituent chemical components, such as hydrogen and oxygen.
- An apparatus that decomposes a compound, especially water, into its elements by means of an electric current passed through it.
"The new plant will install a bank of electrolyzers to produce green hydrogen from surplus wind power."
"Each electrolyzer can convert roughly one ton of water per hour into hydrogen and oxygen."
"Engineers inspected the alkaline electrolyzers before commissioning the hydrogen storage facility."
Regular plural formation. In British English, spelled 'electrolysers'.
"The plant operates dozens of large-scale electrolyzers around the clock."
Every electrolyzer is essentially a machine running photosynthesis in reverse — except instead of making sugar and oxygen from water and light, it makes hydrogen and oxygen from water and electricity.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of electrolyzer
The word electrolyzer derives from 'electrolysis', a term coined in the early nineteenth century by combining the Greek roots 'ēlektron' (amber, associated with electric phenomena) and 'lysis' (loosening, dissolution). The suffix '-er' was then appended to denote an agent or instrument that carries out this process. Related words sharing these Greek origins include 'electricity' and 'analysis'.
How electrolyzer is actually used
Primarily a technical and scientific term, used in chemistry, engineering, and energy-industry contexts. It has become increasingly prominent in discussions of renewable energy and the 'green hydrogen' economy. The British spelling is typically 'electrolyser'.
Easily confused with electrolyzer
An electrolyte is a substance that conducts electricity when dissolved or molten, while an electrolyzer is the apparatus that performs electrolysis using such a solution.