Blue or Green Hydrogen ?

  • Green Power
  • Published on April 11, 2023

Blue hydrogen and green hydrogen are two types of hydrogen produced using different methods, which have implications on their environmental impact.

Production method:

  • Blue hydrogen: Blue hydrogen is produced from natural gas using a process called Steam Methane Reforming (SMR). During SMR, natural gas reacts with high-temperature steam, resulting in hydrogen and carbon dioxide (CO2).
  • Green hydrogen: Green hydrogen is produced from water using a process called electrolysis. In this process, electricity is used to split water (H2O) into hydrogen (H2) and oxygen (O2).

Carbon emissions:

  • Blue hydrogen: During the production of blue hydrogen, CO2 is generated as a byproduct. To mitigate the environmental impact, the CO2 is captured and stored using a technology called Carbon Capture and Storage (CCS). However, not all CO2 emissions can be captured, making blue hydrogen less environmentally friendly than green hydrogen.
  • Green hydrogen: Green hydrogen is considered a zero-emission fuel since its production process only generates water and oxygen as byproducts. If the electricity used for electrolysis comes from renewable sources (e.g., solar, wind, or hydro), the entire process is considered sustainable and carbon-free.

In summary, the key differences between blue and green hydrogen lie in their production methods and environmental impact. Blue hydrogen is produced from natural gas and generates CO2 emissions, while green hydrogen is produced from water using renewable energy and is considered a zero-emission fuel.