UPSC Prelims 2019 · Question 83 of 99

UPSC Prelims 2019 question on Hydrogen CNG Fuel

In the context of proposals to the use of hydrogen-enriched CNG (H-CNG) as fuel for buses in public transport, consider the following statements:

1. The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.

2. H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.

3. Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.

4. H-CNG makes the fuel less expensive than CNG.

Which of the statements given above is/are correct?

  1. 1 only
  2. 2 and 3 only
  3. 4 only
  4. 1, 2, 3 and 4
Show answer

Answer: B. 2 and 3 only

Verdict

Correct statements: 2 and 3 → Option (b).

Statement by statement

Statement 1 – INCORRECT: H-CNG is a blend of hydrogen and CNG, the ideal hydrogen concentration being 18%. Compared to conventional CNG, use of H-CNG can reduce emission of carbon monoxide up to 70% and 15% reduction in total hydro carbon emissions, besides enabling up to 5% savings in fuel. The main advantage is reducing carbon monoxide emissions, but not the elimination of them entirely.

Statement 2 – CORRECT: H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.

Statement 3 – CORRECT: Hydrogen up to one-fifth (20%) by volume can be blended with CNG as fuel for buses.

Statement 4 – INCORRECT: In its report to the Supreme Court, the EPCA estimated that to fuel Delhi's 5,500 buses, about 400 tonnes H-CNG would be needed per day. The cost of H-CNG would not be more than Rs 43 per kg — roughly comparable to CNG at Rs 42, so it does not make the fuel less expensive than CNG.

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