The Cost of Green Hydrogen

Hydrogen is a highly versatile energy carrier. It can be used as a feedstock in refining, ammonia, and iron & steel industries; as a fuel for heavy vehicles, planes and ships and even used to generate electricity and heat. Hydrogen can be compressed, liquified or chemically converted into ammonia or methanol for long-term storage and transport.

Since it’s only by-product when used to produce energy is water, hydrogen is considered an important tool to help decarbonize ‘hard-to-abate’ sectors. In its Net Zero Emissions scenario, the International Energy Agency sees global Hydrogen demand increasing six-fold by 2050. Countries across the world are deploying national hydrogen strategies and policies to support growth in Hydrogen production and usage. The US has passed the Inflation Reduction Act that offers tax credits to low carbon Hydrogen producers. The European Union’s policy initiatives like Fit for 55, REPowerEU and Hydrogen Bank aim to subsidize green hydrogen projects and help scale electrolyzer manufacturing. Other countries like UK, India, China, Chile etc have announced ambitious low carbon / clean hydrogen production targets.

One of the cleanest ways of producing hydrogen is through electrolysis, where electricity from renewable sources such as wind and solar is used to split water into hydrogen and oxygen. Hydrogen produced this way is commonly referred to as green hydrogen (See figure 1).

Figure 1. Green Hydrogen Production

However, green hydrogen is also currently the most expensive form of hydrogen which discourages its commercial deployment on a large scale. Supported by government incentives, the fall in renewable electricity costs and an increase in scale, the industry expects green hydrogen to start becoming cost competitive with fossil-fuel derived hydrogen by 2030.

In this drive for cost reduction, key industry players, such as EPC Contractors, Original Equipment Manufacturers (OEM) and End-users, should also focus on two key processing functions, identified as having a high potential for cost reduction by the industry body IRENA (see Figure 2).

Both Water/Electrolyte processing and Hydrogen (end product) purification are directly impacted by filtration.

Figure 2: Electrolyzer system components classified by potential for cost reduction

Selecting the right filtration technology can help project developers significantly reduce their Capex and OPEX in the following ways:

• Reduce the number and size of unit operations needed to purify hydrogen.
• Protect expensive/critical equipment and avoid unplanned maintenance.
• Improve energy efficiency.

Until recently, the size of green hydrogen installations was quite small, limited to a few MWs of hydrogen production capacity which typically employed bag filters, knock-out drums and demisters for filtration and separation.

However, over the coming few years, the size of green hydrogen projects will multiply several hundred-fold.  The low-efficiency filtration and separation solutions now in use are not conducive to scaling-up as they become impractically large and prohibitively expensive when handling larger flow rates. They are also unable to extract fine particles or aerosols limiting the quality standards that could be achieved.

OEMs, EPCs and End-users need to start incorporating absolute rated particulate filters and high efficiency liquid/gas coalescers in green hydrogen projects to optimize their plant design, maximize the lifetime of their critical equipment and improve overall efficiency and reliability.

Stay tuned to our next post on how high-efficiency absolute filters can help protect Alkaline Electrolyzer stacks.

Sources: https://www.irena.org/-/media/Files/IRENA/Agency/Publication/2020/Dec/IRENA_Green_hydrogen_cost_2020.pdf