A report by Hydrogen Council explores hydrogen, examining three critical areas. By using new data on the material intensities of key technologies, the report estimates the amount of critical minerals needed to scale clean hydrogen.
According to the report, the overall material footprint of the sector is unlikely to cause major stress to most material markets involved, indeed in some markets, such as platinum it may actually relieve stress that could occur with the decline in demand from current uses.
However, the broader context of a potentially materially intensive low-carbon transition needs to be borne in mind, implying that materials crucial for different aspects of the hydrogen sector may be under significant strain from demand elsewhere
This means that reducing the material stress from clean hydrogen will be beneficial to both the deployment of the technology, while also reducing any negative impacts relating to GHG emissions and water from the sector.
Boosting recycling and re-use, reducing material intensity, encouraging material substitution, and encouraging designed in circularity are all vital for improving security of supply and reducing material impacts – whilst there are virtuous circles available such as the deployment of clean hydrogen within the mining industry.
Both governments and the private sector have crucial roles to play in this regard, from establishing the right policy frameworks, to implementing technology transfer, to innovating and investing in efficiency and new technologies
Assessing the environmental impacts of hydrogen technologies
Beyond these challenges understanding the material implications of the widespread deployment of clean hydrogen is important for helping to first understand, and then help to mitigate, the environmental impacts from sourcing the materials needed for clean hydrogen production and consumption.
GHG emissions of the materials required for renewable hydrogen are likely to be higher than for low-carbon hydrogen. Emissions from materials for renewable hydrogen are predominantly accounted for by the need to build renewable technologies to power electrolyzers.
Increasing recycled content in these technologies, improving efficiency and lifetimes of technologies, reducing material intensities, and implementing the World Bank Group’s Climate-Smart Mining (CSM) principles in the mining sector more broadly can help to reduce the emissions associated with the materials needed for the hydrogen sector.
At a macro-scale the overall water footprint of the hydrogen sector is likely to be small compared to other energy sectors, and renewable water resources as a whole – however there maybe challenges at a regional or water-shed level especially as it pertains to water quality, requiring careful assessment of the water impact of projects, and choice of water sourcing, including the use of desalination where relevant.
The water footprint of the materials needed is small compared to the water needed to produce both renewable and low-carbon hydrogen and the fuel cells to power vehicles, though it is likely to rise over-time.
Regionally the broader challenges of water availability for producing renewable and low-carbon hydrogen are likely to be largest in the Middle East, and to a lesser extent in Japan, South Korea, and China.
Incentivizing increased water recycling and reuse; encouraging energy efficient desalination plants powered by renewable energy also equipped with adequate brine management systems where appropriate; investing in solutions that will allow the use of lower-quality water (e.g. salt water, waste water) across the hydrogen sector, along with improving water intensities within mining and processing, and increasing the use of secondary materials, will all help to mitigate this water footprint.
Materiality of renewable power generation outweighs hydrogen technologies
The results of the analysis highlight that the largest source of material demand from the parts of the hydrogen sector modelled are likely to come from the renewable electricity generating capacity needed for renewable hydrogen deployment.
This basket of materials includes aluminum, copper, nickel, and zinc – though the actual scale and composition is highly dependent on the type (and sub-types) of renewable electricity used to power electrolyzers.
Higher use of solar photovoltaics (PV) could increase the demand for aluminum, whilst more use of wind could increase the need for zinc, or even dysprosium and neodymium if wind turbines with permanent magnets are used.
Beyond these materials there is a wide grouping of other materials that are needed in smaller absolute volumes but spread across the different types of hydrogen-related technologies from platinum and iridium to cerium and cobalt. Some are used in just a singular technology such as cerium for fuel-cells while others are used widely across the sector such as nickel and titanium.