ECO-POWER DRIVING FORWARD THE COMMERCIALISATION OF P2G Power to Gas (P2G) is seen as an essential solution for achieving carbon neutrality by 2050.


Here, Toshiba Corporation explains how Polymer Electrolyte Membrane (PEM) water electrolysers for power to gas technology will help by contributing to realisation of a hydrogen economy


T


oshiba Corporation has developed large-scale production technology for the electrodes that


realises high level efficiency in Power to Gas (P2G) technology – essential know-how for advancing toward a carbon neutral society – while reducing the use of iridium, one of the world’s rarest precious metals, to 1/10 *1


. P2G uses electrolysis of water to convert


renewable energy into hydrogen, for storage and transportation to where it is needed. Polymer Electrolyte Membrane (PEM) electrolysis is seen as a highly promising conversion method, as it is reacts rapidly to power fluctuations and is highly durable. However, PEM uses iridium, one of the rarest of all traded precious metals, as the catalyst in its electrodes. Practical application requires reduction of the iridium used, and this is a real challenge. Toshiba has developed an


iridium oxide nanosheet laminated catalyst that reduced the iridium requirement to 1/10 in 2017. Now, however, it has developed large-scale production technology that deposits the catalyst over a maximum area of 5m2


at one


time. This advance is expected to drive forward the early commercialisation of P2G for large-scale power conversion, and will contribute to the realisation of carbon neutrality. Toshiba is aiming for commercialisation in FY2023 or after.


METING CARBON NEUTRALITY GOALS Over 120 countries and regions have set themselves the goal of carbon neutrality by 2050, and decarbonisation measures are being considered at the national, regional, and corporate levels. Renewables are essential for achieving the goal and


cutting CO2 emissions, but their output fluctuates greatly with climate and weather conditions, and facilities can be located only in suitable regions. To maximise their potential, and ensure a stable and affordable power supply, a method for storing and transporting electricity from renewables is required. P2G is seen as an essential solution for achieving


carbon neutrality by 2050. It uses electrolysis to convert electricity from renewables into hydrogen, ready for storage and transportation. The key technology in the process is the water electrolysers that convert energy into hydrogen without emitting


CO2. PEM water electrolysis offers excellent adaptability to power fluctuations and high durability, and Europe and the US have led the way


www.essmag.co.uk


in developing the current process. PEM uses a membrane electrode assembly (MEA)


that integrates the electrolyte membrane and electrode. Large-scale hydrogen conversion of electricity requires a large number of MEAs, and forecasts anticipate a market scale of approximately $580 million by 2028 *2


. However, the MEA electrode relies on a large


amount of iridium to ensure sufficient electrolytic efficiency. Iridium is one of the rarest of precious metals. Annual global production is in the region of seven to 10 tons, far less than the 200 tons of platinum, and it costs four to five times more *3


.


Forming electrodes requires a uniform coating of fine iridium oxide particles, but reducing the iridium oxide results in uneven application and


The sputtering method


electrolysis performance. It also significantly expands the deposition surface area. As sputtering is conducted in a vacuum, deposition on a large area is difficult. However, by modifying the deposition distribution ratio for multiple metal targets, including iridium, and the oxygen input level, Toshiba has successfully developed a large-scale production technology that realises catalyst deposition on an area of up to 5m2


at a time. In collaboration with Toshiba Energy Structures of Oxide Nanosheet and MEA, developed by Toshiba


non-uniform reactions that degrade water electrolysis performance. Toshiba’s multilayer catalyst uses a new


sputtering technology to deposit alternate layers of iridium oxide nanosheet films and void layers. In sputtering, ions, such as argon, bombard a deposition material, the target, in a vacuum, and deposit the ejected particles on a substrate. In Toshiba’s process, iridium is the target, and a thin film of iridium oxide is formed by injecting oxygen as the target is deposited on the substrate. Thickness control is at the nanometer level, realizing deposition of uniform iridium oxide layers of with a smaller amount of iridium. Using Toshiba’s laminated nanosheet structure in


the catalyst layer successfully reduces the required iridium to 1/10, while maintaining the water


*1 : https://www.global.toshiba/content/dam/toshiba/migration/corp/techReviewAssets/tech/review/2018/


03/73_03pdf/a03.pdf https://www.global.toshiba/content/dam/toshiba/jp/technology/corporate/review/2022/04/a04.pdf *2 *3


: Toshiba’s estimate : https://matthey.com/pgm-market-report-2022


Systems & Solutions Corporation, Toshiba has built MEA prototypes with electrodes based on the developed technology, and has begun evaluation testing with a water electrolyser manufacturer. Going forward, the Company will improve the yield and quality toward mass production of MEA,


aiming for commercialisation in FY2023 or after.


Toshiba Corporation https://www.global.toshiba/ww/top.html


ENERGY & SUSTAINABILITY SOLUTIONS - Winter 22/23


23


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40