Transitioning SA's Petrochemical Value Chain

Hydrogen production

Hydrogen can be produced from diverse resources including coal, natural gas and water – each with different production pathways, energy inputs and emissions. Global annual hydrogen production is currently to the order of 120 Mt. Sasol is the largest single producer and user of hydrogen globally (Business Engagement).

More than 60% of hydrogen is produced in dedicated hydrogen production facilities – mainly via steam reformation of natural gas, and a smaller portion via the gasification of coal (see a high-level Sankey Diagram of the Global Hydrogen Value Chain). The rest is produced as a by-product from facilities designed to produce other products, and is usually supplied in a mixture with other gases.

To produce hydrogen from gas or coal, the feedstock is split into hydrogen and carbon dioxide (CO2), with the CO2 typically being released into the atmosphere, resulting in the processes being highly emissions-intensive. Hydrogen produced via these pathways is termed ‘grey hydrogen’, and in the case of coal can sometimes be termed ‘black’ or ‘brown’. If the carbon dioxide emitted during production is captured and stored using carbon capture technologies, the hydrogen is known as ‘blue hydrogen’.

‘Green hydrogen’ is produced by splitting water into hydrogen and oxygen using an electrolyser powered by renewable electricity (wind, solar or hydro), without producing emissions. Only 1 to 2% of global hydrogen production is currently produced in this way.