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?
- (a) 1 only
- (b) 2 and 3 only ✓ UPSC's answer
- (c) 4 only
- (d) 1, 2, 3 and 4
Why the answer is (b)
• H-CNG blends about 18% hydrogen by volume with CNG — roughly one-fifth (statement 3); in 2019 the Supreme Court allowed a 50-bus H-CNG pilot in Delhi.
• Statement 2 is correct: IOC trials showed H-CNG cuts hydrocarbon emissions and improves fuel efficiency, lowering CO2 per km.
• Statement 1 is wrong: H-CNG reduces carbon monoxide by up to 70%, but does not eliminate it.
• Statement 4 is wrong: producing and blending hydrogen adds cost; H-CNG is not cheaper than CNG.
• Hence 2 and 3 only, option (b).
Why the other options are wrong
- (a) 1 only
- Statement 1 is wrong: CO is reduced, not eliminated.
- (c) 4 only
- Statement 4 is wrong: H-CNG is not cheaper.
- (d) 1, 2, 3 and 4
- Statements 1 and 4 are wrong.
Asked in the GS Paper I of the UPSC Civil Services Preliminary Examination 2019, held on 2 June 2019. Question and answer key: Union Public Service Commission. Explanation: UPSC Answer Check.