Hydrogen is a colourless gas. It exists in various forms with different production methods and environmental impacts, hence given different names to understand the nature of Hydrogen. Understanding these types of hydrogen is crucial for navigating the transition to cleaner energy sources.
Green Hydrogen:
It is produced using clean electricity from surplus renewable energy sources like solar or wind power to electrolyze water. Currently, Green Hydrogen represents a small percentage of overall hydrogen production due to its expense, but its cost is expected to decrease as renewable energy becomes more prevalent.
Blue Hydrogen:
It is primarily derived from natural gas through steam reforming, resulting in hydrogen production along with carbon dioxide as a by-product. It includes the utilisation of carbon capture and storage (CCS) technology to capture and store the emitted carbon dioxide.
Grey Hydrogen:
This is the most common form of hydrogen production. It is generated from natural gas or methane through steam methane reformation without capturing greenhouse gases emitted during the process, similar to blue hydrogen but without CCS.
Black and Brown Hydrogen:
It is produced using black coal or lignite (brown coal) in the hydrogen production process. Considered highly environmentally damaging, representing the opposite end of the spectrum from green hydrogen.
Pink Hydrogen:
Pink Hydrogen is generated through electrolysis powered by nuclear energy, also known as purple or red hydrogen.
Turquoise Hydrogen:
It is produced via methane pyrolysis to yield hydrogen and solid carbon. Potential for low-emission hydrogen if the thermal process is powered by renewable energy and the carbon is either stored or utilised.
White Hydrogen:
It is a naturally occurring hydrogen found in underground deposits, created through fracking. Currently, there are no active strategies for its exploitation.
