UPSC Prelims 2023 Question:

With reference to green hydrogen, consider the following statements:

1. It can be used directly as a fuel for internal combustion.
2. It can be blended with natural gas and used as fuel for heat or power generation.
3. It can be used in the hydrogen fuel cell to run vehicles.
   
   

How many of the above statements are correct?

Explanation:

• Green hydrogen can be used directly as a fuel for internal combustion by a hydrogen engine (HCE). HCE is an engine that uses hydrogen (H2) as fuel. It is a modified gasoline-powered engine but doesn't emit any carbon-based pollution, which is a big benefit towards carbon neutrality. HCEs operate similarly to 4-stroke gasoline engines (ICEs). But compared to gasoline, which has an octane rating of 90 (for premium gasoline), hydrogen has a higher-octane number of 130. So, statement 1 is correct.
  
  

• Hydrogen produced through clean pathways can be injected into natural gas pipelines, and the resulting blends can be used to generate heat and power with lower emissions than using natural gas alone. So, statement 2 is correct.
  
  

• A fuel cell uses the chemical energy of green hydrogen or other fuels to cleanly and efficiently produce electricity. If hydrogen is the fuel, the only products are electricity, water, and heat. So, statement 3 is correct.
  

Therefore, option (3) is the correct answer. 

Subject: Environment | Renewable and Energy Resources