UPSC CSE Prelims
Question 70
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 :
- The main advantage of the use of H-CNG is the elimination of carbon monoxide emissions.
- H-CNG as fuel reduces carbon dioxide and hydrocarbon emissions.
- Hydrogen up to one-fifth by volume can be blended with CNG as fuel for buses.
- H-CNG makes the fuel less expensive than CNG.
Which of the statements given above is/are correct?
View correct answer and explanation
Correct answer: B
Correct Option: B
Explanation:
Hydrogen-enriched CNG can reduce CO₂ and hydrocarbon emissions and trial blends around 18–20% hydrogen by volume were explored for buses. It cannot eliminate all CO, and hydrogen blending is not inherently cheaper than CNG.
Statement / Pair Analysis:
1 (Incorrect): H-CNG may reduce CO emissions, but does not guarantee complete elimination.
2 (Correct): Hydrogen enrichment can improve combustion and lower CO₂/hydrocarbon emissions.
3 (Correct): Roughly one-fifth hydrogen by volume can be blended into CNG in relevant bus trials.
4 (Incorrect): Hydrogen production, blending and infrastructure generally add costs; lower price is not assured.
Option-wise Analysis:
A (Incorrect): It includes false item 1 (H-CNG may reduce CO emissions, but does not guarantee complete elimination); omits true item 2 (Hydrogen enrichment can improve combustion and lower CO₂/hydrocarbon emissions); omits true item 3 (Roughly one-fifth hydrogen by volume can be blended into CNG in relevant bus trials).
B (Correct): Includes all and only the true statements/pairs.
C (Incorrect): It includes false item 4 (Hydrogen production, blending and infrastructure generally add costs; lower price is not assured); omits true item 2 (Hydrogen enrichment can improve combustion and lower CO₂/hydrocarbon emissions); omits true item 3 (Roughly one-fifth hydrogen by volume can be blended into CNG in relevant bus trials).
D (Incorrect): It includes false item 1 (H-CNG may reduce CO emissions, but does not guarantee complete elimination); includes false item 4 (Hydrogen production, blending and infrastructure generally add costs; lower price is not assured).
Review Note:
Emissions reductions depend on vehicle engines, hydrogen production pathway and blend ratio.