UPSC Prelims 2023 Q99: Green Hydrogen in Heavy Industry — Explained

Consider the following heavy industries:

1. Fertilizer plants

2. Oil refineries

3. Steel plants

Green hydrogen is expected to play a significant role in decarbonizing how many of the above industries?

  1. Only one
  2. Only two
  3. All three
  4. None

Answer: (c) All three

Statement-wise explanation

  • 1: correct — Fertilizer plants make ammonia by the Haber–Bosch process (N₂ + 3H₂ → 2NH₃), and nearly all of that hydrogen now comes from natural gas, much of it imported. If green hydrogen replaces this 'grey' hydrogen, you get green ammonia and then green urea. The process stays the same. Only the source of the feedstock changes. Ammonia for fertilizers is the largest single user of hydrogen in India, and the National Green Hydrogen Mission (NGHM) has a separate allocation for the fertilizer sector under its SIGHT programme.
  • 2: correct — Refineries already use large amounts of hydrogen for hydrotreating (removing sulphur to meet BS-VI fuel norms) and for hydrocracking. They make it mostly by steam methane reforming of natural gas, which releases CO₂. Replacing that grey hydrogen with green hydrogen cuts emissions without changing the refinery's equipment. Under the NGHM, green hydrogen supply has been tendered for the refineries of IOCL, BPCL, HPCL and Numaligarh Refinery.
  • 3: correct — Conventional steel uses coke in a blast furnace to strip oxygen from iron ore, and this releases CO₂. In hydrogen-based direct reduced iron (DRI), hydrogen does that reducing job instead, so the by-product is water vapour rather than CO₂. The NGHM made the steel sector a stakeholder and funded pilot projects for injecting hydrogen into DRI plants and blast furnaces. The Ministry of Steel's roadmap names green-hydrogen steelmaking as a key route for 2030–2047.

How to eliminate

Statement analysis alone won't solve this one. You have to know how each industry uses hydrogen. The fact to remember is simple, though. Green hydrogen helps decarbonise a sector in two ways: by replacing grey hydrogen that the sector already consumes, or by replacing coal or gas used as a chemical reductant. Refineries (hydrotreating) and fertilizer plants (ammonia) are the two biggest hydrogen consumers today, so both are almost certain. That alone rules out the options of none and only one. To choose between two and three, recall 'hydrogen DRI' or 'green steel', which is the best-known example of a hard-to-abate sector decarbonising with hydrogen. Each of the three named sectors appears in the NGHM's list of end uses. One general hint: when UPSC lists three 'hard-to-abate' heavy industries and asks how many fit a flagship clean-energy technology, the answer is often all of them. Treat that as a weak tiebreaker, not a rule.

Know more

Hydrogen 'colours' describe how hydrogen is made. The molecule is the same in every case.

Colour How it is made CO₂ footprint
Grey Steam methane reforming of natural gas High (roughly 9–12 kg CO₂ per kg H₂)
Blue Grey process + carbon capture and storage Lower
Green Electrolysis of water using renewable power Near zero (India's standard: ≤ 2 kg CO₂e per kg H₂)

Why heavy industry? Fertilizers, refining and steel are 'hard-to-abate' sectors. Their emissions come from chemistry, not just from the energy they use. Using renewable electricity alone cannot remove them.

Industry Role of hydrogen What green H₂ replaces
Fertilizers Feedstock for ammonia (Haber–Bosch), then urea Natural-gas-based grey H₂
Oil refining Hydrotreating/desulphurisation, hydrocracking Grey H₂ from SMR
Steel Reducing agent for iron ore (H₂-DRI) Coking coal / natural gas
Shipping, long-haul transport Fuel as green ammonia/methanol Bunker fuel, diesel

National Green Hydrogen Mission (NGHM): approved by the Union Cabinet on 4 January 2023 and run by MNRE.

  • Total outlay: ₹19,744 crore up to FY 2029-30. This includes ₹17,490 crore for SIGHT (Strategic Interventions for Green Hydrogen Transition), which gives incentives for making electrolysers and producing green hydrogen, and ₹1,466 crore for pilot projects (steel, mobility, shipping).
  • Target: 5 MMT of green hydrogen a year by 2030, with about 125 GW of linked renewable capacity.
  • Expected benefits: about 50 MMT a year of CO₂ emissions avoided.

Derivatives: green ammonia and green methanol are easier to store and ship than hydrogen gas. That is why export deals and port projects (Paradip, Kandla, Thoothukudi) focus on these derivatives.

In the news

The Union Cabinet approved the National Green Hydrogen Mission on 4 January 2023, less than five months before the 2023 Prelims. The mission named fertilizers, refining and steel as the main domestic users of green hydrogen.

NCERT Concepts to Revise

  • Green hydrogen: The question turns on what makes hydrogen 'green': electrolysis powered by renewables, in contrast to the grey hydrogen these industries use now.
  • National Green Hydrogen Mission: The mission names the industrial end-users of green hydrogen and funds sector-specific incentives and pilot projects.

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