The method by which blue hydrogen is produced is decisive in determining whether it is harmful to the environment or whether it can be regarded as climate-friendly. A study has now shown that under certain conditions blue hydrogen can make a positive contribution to the energy transition. The study was carried out by an international group of researchers formed by Christian Bauer from the Laboratory for Energy Systems Analysis (LEA) at the Paul Scherrer Institute (PSI) and Mijndert van der Spek, Professor at the Research Centre for Carbon Solutions (RCCS) at Heriot Watt University in Edinburgh, Scotland.
Green hydrogen is obtained from water using renewable energies, while blue hydrogen is derived from natural gas. The CO2 generated during the production process is collected and stored underground. An American study published in August came to the conclusion that blue hydrogen was even just over 20 percent worse for the environment than fossil natural gas. The authors based this view on the fact that its main component methane can escape owing to leaks along the entire natural gas supply chain and during production itself. The gas has a greenhouse gas effect 30 times stronger than CO2.
In contrast, however, the results from the latest study offer a different picture, according to a press release issued by PSI: “Depending on the production technology and the country of extraction, emissions can vary between a few tenths of a percent to several percent”, Christian Bauer explains. Moreover, when it comes to capturing the carbon dioxide, some methods are able to trap and store almost all CO2, while others are only capable of working to around 50 percent.
Accordingly, the key to generating blue hydrogen in a climate-friendly manner is implementing high technological standards. Bauer explains that his research group has demonstrated that “if managed correctly, this type of hydrogen can make a valuable contribution towards the energy transition”, at least as an interim solution. Because, according to Bauer, in this way blue hydrogen could be just as environmentally friendly as its green counterpart.
