PSI looking at options for hydrogen production

Researchers from the Paul Scherrer Institute (PSI), based in the canton of Aargau in Switzerland, have been grappling with the question as to where hydrogen can be produced efficiently and inexpensively, with the aim of counteracting climate change and in future releasing no net additional greenhouse gases into the atmosphere. The researchers collated geographical and economic data and projections in order to describe the way in which a hydrogen economy might be constructed, further details of which can be found in a press release. To this end, they analyzed four scenarios with hydrogen requirements of between 111 and 614 megatons per year. The study has been published in the latest edition of the journal “Nature Communications”.

There are various technologies that can be used for the production of hydrogen. For example, polymer electrolyte membrane electrolysis (PEM) is one such method in which hydrogen is extracted from water in an electrolyzer. The major benefit of this process is that the energy for the conversion can be obtained from green electricity, although clarity is required in terms of where the high demand for green electricity can best be met.

“We primarily applied economic criteria”, comments Tom Terlouw, a PhD student at PSI and lead author of the study, in the press release. “In other words, we looked at where production would be most inexpensive”, he adds. In this context, two key factors began to emerge: Where is there sufficient wind and sun to meet the huge demand for green electricity? And where is there enough free space suitable for the construction of the necessary production facilities? Canada emerged as an optimal choice in this regard. “There are lots of open spaces which are very windy and therefore ideal for putting up wind turbines”, as Terlouw explains. Central parts of the USA, areas of Australia, the Sahara, northern China and northwestern Europe represent alternative options. However, central European countries such as Switzerland are less suitable for hydrogen production because scarcely any land is available for wind turbines, while solar radiation levels are also relatively low. Moreover, the researchers point out that even the production of green hydrogen will still see residual emissions of greenhouse gases generated from the production and transportation of the required materials. In order to offset these residual emissions, corresponding amounts of carbon dioxide would have to be filtered out of the atmosphere, the study explains. ce/eb