Hydrogen is renewable only if the process used to extract it is also renewable. Hydrogen itself is not a primary energy source but an energy vector, requiring a chemical process for its production.
Here's a breakdown:
-
Hydrogen as an Energy Carrier: Unlike naturally occurring resources like sunlight or wind, hydrogen needs to be produced. Think of it as a way to store and transport energy, rather than an energy source itself.
-
Renewable vs. Non-Renewable Production: The crucial factor is how the hydrogen is produced.
- Renewable Hydrogen: If produced using renewable energy sources (solar, wind, hydro) to power the extraction process (e.g., electrolysis of water), then the hydrogen is considered renewable or "green" hydrogen.
- Non-Renewable Hydrogen: If produced using fossil fuels (e.g., steam methane reforming), it's not renewable, often called "grey" or "blue" hydrogen (if carbon capture is involved).
Here's a table summarizing different types of hydrogen production:
| Hydrogen Type | Production Method | Renewable? | Environmental Impact |
|---|---|---|---|
| Green | Electrolysis using renewable energy | Yes | Low |
| Blue | Steam Methane Reforming with CCS | Potentially | Lower than grey, but still significant |
| Grey | Steam Methane Reforming | No | High (significant carbon emissions) |
| Brown/Black | Coal Gasification | No | Very High (highest carbon emissions) |
Essentially, the "renewability" of hydrogen hinges entirely on the source of energy used to create it.
