Green hydrogen

noun (uncountable)

/ɡriːn ˈhaɪdrədʒ(ə)n/

Hydrogen produced by the electrolysis of water using electricity generated exclusively from renewable energy sources such as solar, wind, or hydropower, resulting in zero net carbon emissions during production — contrasted with grey hydrogen (from natural gas without carbon capture), blue hydrogen (from natural gas with CCS), and brown/black hydrogen (from coal). In UPSC context, India's National Green Hydrogen Mission (NGHM, launched January 2023, outlay ₹19,744 crore) targets 5 MMT/year of green hydrogen production and 500 GW of renewable capacity by 2030, supported by the SIGHT (Strategic Interventions for Green Hydrogen Transition) programme, aiming to make India a global export hub.

✍️ Usage in a UPSC answer

The SIGHT programme under India's National Green Hydrogen Mission offers production-linked incentives to electrolyser manufacturers to drive down the cost of green hydrogen below $1 per kilogram — the price threshold at which it becomes competitive with fossil-fuel-derived grey hydrogen.

Synonyms

renewable hydrogenelectrolytic hydrogenclean hydrogenzero-carbon hydrogen

Antonyms

grey hydrogenbrown hydrogenblue hydrogenfossil hydrogen

🌱 Word Family

green hydrogen (n), grey hydrogen (n), blue hydrogen (n), hydrogen economy (n phrase), electrolyser (n, production tool), hydrogen fuel cell (n phrase), NGHM (abbr)

🔡 Root

Old English grēne = green colour, associated with environmental sustainability from 1970s activism; Greek hydro- = water + -gen = producing (from Greek gennan = to produce) — hydrogen 'produces water' when burned

📜 Etymology

The word hydrogen was coined by French chemist Antoine Lavoisier in 1787, from Greek hydro- ('water') + -genes ('producing'), as hydrogen produces water when combusted. The colour-coding of hydrogen by production method (grey, blue, green) emerged in the 2010s in energy policy literature, with 'green' signifying renewables-powered production.

🧠 Memory Hook

GREEN = renewable energy input; HYDROGEN = water-producer (Greek hydro-genes). Picture a solar panel powering a water splitter (electrolyser): sun in, H₂ out, zero carbon released. The NGHM 2023 and ₹19,744 crore outlay are the Prelims anchors. 'Green' is the power source colour, not the gas.

📝 Seen in UPSC Question Papers

Prelims 2023 — Biotechnology

Real UPSC previous-year questions whose text uses “Green hydrogen” — proof this word earns its place on your list.

🔬 Science & Technology 📖 Seen in: Emerging Technologies — AI, Quantum Co... 📋 Also in Key Terms

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