In July 2022, the International Renewable Energy Agency (IRENA) released a series of reports collectively entitled: Global Hydrogen Trade to Meet the 1.5 Climate Goal. The series contains three reports: ① Trade Outlook for 2050 and Way Forward, ② Technology Review of Hydrogen Carriers, and ③ Green Hydrogen Cost and Potential.
Until recently, there has been no cost-effective way to transport hydrogen to remote areas, but the establishment of cost-effective methods to store and transport it as liquids and compounds has led to hydrogen being projected as a next-generation energy source in the transition to a decarbonized society. These reports explore the supply chain of hydrogen as an energy source in terms of trade, technology, and cost.
The first report examines hydrogen supply and infrastructure to assess the outlook of the global hydrogen trade by 2050, looking at the cost and technical production potential of green hydrogen for the world in 2030 and 2050 under different scenarios and assumptions.
Of the hydrogen that would be internationally traded by 2050 in the 1.5 scenario, around 55% would travel by pipeline, and the remaining 45% would be shipped, predominantly as ammonia. The cost of shipping ammonia is projected to decline from USD 8/kgH2 to USD 0.8/kgH2. In addition, the production of green hydrogen requires electricity to process renewable energy through electrolysis to convert it into hydrogen and to increase its energy density. The upscaling and acceleration of renewable energy generation is crucial for the transition to green hydrogen; the production of renewable energy needs to at least triple from today’s 290 GW/year to more than 1 TW/year by the mid-2030s. Over 10,000 GW of wind and solar power would be needed by 2050 solely for green hydrogen production and trade. It is also noted that the scale of electrolysis units will need to increase from 700 MW in 2021 to 4-5 TW by 2050.
The second report compares the transport of hydrogen by pipeline as compressed gaseous hydrogen with three other shipping pathways: ammonia, liquid hydrogen and liquid organic hydrogen carriers (LOHC). The cost of all four options are calculated by the size of the production facility and by the transport distance. The largest available benefit is achieved with project sizes of 0.4 MtH2/year for LOHC and ammonia, and 0.95 MtH2/year for liquid hydrogen. In terms of transport distance, the results show that ship transport of ammonia is the most efficient over a wide range of conditions, with the efficiency of ship transport of ammonia increasing with transport distance. The cost for pipelines, on the other hand, scales linearly with distance, and pipelines are the cheapest option for short distances of up to 3000 km. In cases where repurposed pipelines are possible, the investment cost can be 65-94% lower than the cost of a new hydrogen pipeline, and this expands the distance for which pipelines are attractive to up to 8,000 km. The main disadvantage of shipping liquid hydrogen lies in the low temperature requirement (-253℃). Liquid hydrogen can be attractive for relatively short distances, and in instances where pipelines are not an option (e.g. Japan, South Korea, islands), liquid hydrogen can be attractive for large flows and distances of up to around 4,000 km. LOHC has advantages such as the availability of existing facilities, chemical stability, and low boil-off loss (i.e., loss due to vaporization) during transportation and storage, but it faces many technical challenges in its practical application.
The third report assesses the cost and potential of green hydrogen production, taking into account geographical conditions. The production cost of hydrogen is dependent mainly on the cost of the renewable input and the electrolyser. In 2050, almost 14 TW of solar PV, 6TW of onshore wind and 4-5 TW of electrolysis will be needed to achieve a net zero emissions energy system. The cost of green hydrogen production could reach levels of almost USD 0.65/kgH2 for the best locations in the most ideal scenario, but in a less optimistic scenario, the lowest production cost is USD 1.15-1.25/kgH2. Notably, Japan and South Korea are categorized as the most restricted region in the potential of green hydrogen production.
To prevent global warming, it is essential to utilize renewable energy and not depend on fossil fuels that emit a large amount of CO2. Still, transporting and storing renewable energy on a large scale has challenges ahead, such as long-distance transport logistics and storage batteries. A system that electrolyzes water with renewable energy and uses the hydrogen produced without generating CO₂ as an energy carrier is the solution, but in order for it to be widely used, safe, large-scale storage and transportation of hydrogen must be possible.
IRENA  Global Hydrogen Trade to Meet the 1.5℃ Climate Goal
Part I: Trade Outlook for 2050 and Way Forward
Press Release: A Quarter of Global Hydrogen Set for Trading by 2050