Technology : Electronics And Green Technology

Q 20 / 38

UPSC CSE Prelims 2019

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?

EXPLANATION

Correct Option

Statements 2 and 3 are correct.

  • H-CNG as fuel contributes to a reduction in carbon dioxide (CO₂) and unburnt hydrocarbon emissions. The presence of hydrogen in the blend promotes more complete combustion, leading to these environmental benefits.
  • Hydrogen can be blended with CNG for use as fuel in buses, with studies and pilot projects indicating that blending up to 18-20% by volume (approximately one-fifth) is feasible and effective. This proportion enhances combustion efficiency without necessitating major engine modifications.

Incorrect Options

  • Statement 1 is incorrect. While H-CNG significantly reduces carbon monoxide (CO) emissions, often by a substantial percentage, it does not lead to the complete elimination of these emissions.
  • Statement 4 is incorrect. H-CNG is generally more expensive than conventional CNG. The higher cost is primarily due to the energy-intensive process involved in blending hydrogen and the additional infrastructure required for hydrogen production, storage, and distribution.
SOURCEEnvironment by Shankar IAS, Chapter 15: Renewable Energy