{"schemaVersion":1,"slug":"hydrogen-electrolyser","name":"Hydrogen electrolyser","kind":"symbol","abbreviation":"ELY","aliases":["electrolyser","water electrolysis unit","PEM electrolyser"],"category":"microgrid-systems","drawingTypes":["SLD"],"referenceFamilies":["IEC","IEEE / ANSI"],"summary":"A DC load that splits water into hydrogen and oxygen, supplied through a rectifier as a controllable sink in a microgrid.","description":["An electrolyser uses DC current to split water into hydrogen and oxygen. In microgrids and renewable hubs it acts as a large controllable load that can absorb surplus solar or wind generation, with the hydrogen stored for later use in a fuel cell or sold off site.","On a single-line diagram the electrolyser stack appears as a DC load fed from a transformer-rectifier or an active front-end rectifier. Large units show the rectifier transformer, harmonic filtering and a DC busbar to the stack; smaller units may be drawn as a single block labelled with the stack rating.","Thyristor rectifiers for large electrolysers draw significant harmonic current and reactive power, so filters or compensators may be needed. The symbol does not state ramp rate, minimum load or the gas plant constraints that limit how flexibly the electrolyser can follow generation."],"readingNotes":["Read the rectifier type to judge harmonic and reactive impact.","Treat the stack as DC load; its rating is often given in MW of DC input."],"drawingChecklist":["State stack DC rating and ramp limits.","Show rectifier, transformer and filters.","Reference minimum load and process interlocks."],"distinction":"An electrolyser consumes electricity to make hydrogen; a fuel cell consumes hydrogen to make electricity.","facts":[{"label":"Electrical role","value":"Controllable DC load"},{"label":"Supply","value":"Rectifier from AC network"},{"label":"Power quality","value":"Rectifier harmonics may need filtering"},{"label":"Preview","value":"Independent educational illustration; consult the applicable standard and project legend for the exact graphic"}],"references":[{"sourceId":"iec-diagrams","relevance":"IEC graphical symbol context for loads and conversion elements."},{"sourceId":"energy-storage","relevance":"Public power conversion context for storage-type systems."}],"related":["fuel-cell","thyristor-phase-controlled-rectifier","active-front-end-rectifier","generic-electrical-load"],"artwork":"s28-hydrogen-electrolyser","publishedOn":"2026-10-28","updatedOn":"2026-10-28","provenance":"independent-public-research","plainEnglish":{"title":"What does Hydrogen electrolyser mean?","introduction":"An electrolyser uses DC current to split water into hydrogen and oxygen. In microgrids and renewable hubs it acts as a large controllable load that can absorb surplus solar or wind generation, with the hydrogen stored for later use in a fuel cell or sold off site.","example":"On a single-line diagram the electrolyser stack appears as a DC load fed from a transformer-rectifier or an active front-end rectifier. Large units show the rectifier transformer, harmonic filtering and a DC busbar to the stack; smaller units may be drawn as a single block labelled with the stack rating.","drawings":"Thyristor rectifiers for large electrolysers draw significant harmonic current and reactive power, so filters or compensators may be needed. The symbol does not state ramp rate, minimum load or the gas plant constraints that limit how flexibly the electrolyser can follow generation.","terms":[{"name":"DC","meaning":"Direct current: electricity flowing in one direction."},{"name":"Winding","meaning":"A coil of conductor inside an electrical machine or transformer."},{"name":"Rating","meaning":"A value stating the conditions for which equipment is specified."}],"diagram":"flow","steps":["Identify the device and form","Read the connections and state","Check the equipment reference"],"caption":"A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram.","sources":[{"label":"IEC graphical symbols for diagrams","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/"},{"label":"Battery energy storage and power conversion","url":"https://www.eaton.com/sg/en-us/products/energy-storage.html"}],"detail":"A DC load that splits water into hydrogen and oxygen, supplied through a rectifier as a controllable sink in a microgrid. An electrolyser consumes electricity to make hydrogen; a fuel cell consumes hydrogen to make electricity.","profileId":"reviewed-symbol-20261028"},"url":"https://eloragrid.ai/symbols/hydrogen-electrolyser","illustration":{"url":"https://eloragrid.ai/tools/electrical-library/illustrations/hydrogen-electrolyser.svg","scope":"Original educational concept; not an official standard graphic or product footprint","license":"https://creativecommons.org/licenses/by/4.0/"},"sources":[{"id":"iec-diagrams","title":"IEC graphical symbols for diagrams","publisher":"IEC","url":"https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/","type":"standard","scope":"IEC 60617 and related symbol-design publications. Full database access requires a subscription.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"IEC graphical symbol context for loads and conversion elements."},{"id":"energy-storage","title":"Battery energy storage and power conversion","publisher":"Eaton","url":"https://www.eaton.com/sg/en-us/products/energy-storage.html","type":"manufacturer","scope":"Explains battery storage and the power-conversion interface. Product-specific installation requirements remain with the manufacturer.","checkedOn":"2026-10-13","reuse":"link-only","relevance":"Public power conversion context for storage-type systems."}]}