FAI Spring 2023 Process Safety News.ai

The Potential Hazards of Hydrogen Elizabeth Meegan, Principal Engineer, Fauske & Associates

Why Hydrogen? Growing interest in hydrogen revolves around the recognition that clean hydrogen could play a crucial role in global decarbonization. Currently 40% of all carbon dioxide emissions come from power plants burning fossil fuels for energy. Other high pollution fields include transportation and industrial factories. Consumption of hydrogen for energy produces only water, and hydrogen carries a high energy density by mass, which makes it an interesting low carbon alternative. The demand for hydrogen has increased threefold since 1975 and is expected to continue this trajectory with the

Where Does Hydrogen Come From? Not all hydrogen is considered “clean” as its production can be carbon intensive, and so while hydrogen is a colorless gas, it is typically described by color to represent its source. Green hydrogen is of particular interest to combat global warming, because it is produced in a “climate-neutral manner.” Table 1 provides a comparison of the commonly discussed hydrogen production methods. demand for clean hydrogen anticipated to be a crucial component of Net Zero Emissions by 2050 Scenario (NZE) with a potential demand of 150 to 500 million metric tonnes of hydrogen a year. To try and meet this demand, there is a global push for financial investment in clean hydrogen at scale in both commercial and industrial applications.

Hydrogen is produced by electrolyzing (splitting) water molecules from surplus renewable energy sources (e.g. solar or wind). This process is carbon free, but currently only makes up 0.1% of overall hydrogen production because it’s very expensive. Hydrogen is produced by steam methane reforming (SMR, brings together steam and natural gas to generate hydrogen). This process does generate carbon dioxide as a product, but it utilizes a carbon capture and storage system to trap and store it. This process is often referred to as low-carbon hydrogen, because only 85-95% of the carbon is typically captured.

Green Hydrogen

Blue Hydrogen

Turquoise Hydrogen

Hydrogen is generated by methane pyrolysis, which is the thermal decomposition of methane into hydrogen and solid carbon, but this process seems primarily experimental currently.

Pink Hydrogen

Analogous to green hydrogen production, except the source of energy is from nuclear power.

Yellow Hydrogen

Primarily considered the production of hydrogen from electrolyzing water using solar energy.

Hydrogen production from biomass. Grey hydrogen is currently the most common form of hydrogen production where hydrogen is generated from natural gas through SMR, but without carbon capture system.

Grey/Black/Brown Hydrogen

3

www.fauske.com

continued on page 4