Blue Hydrogen May Not Be As Green As We Think
Automotive manufacturers around the world are working towards producing vehicles that have no greenhouse gas emissions. While most cars are going electric using batteries, hydrogen is another alternative for potentially green vehicles with little or no emissions. A type of hydrogen called "blue" hydrogen is made from methane taken from natural gas.
Blue hydrogen has been touted as green and an option to help reduce pollution and global warming. However, a new study from Cornell and Stanford University has found that producing blue hydrogen may be more harmful to the environment than using fossil fuels. According to the study, creating blue hydrogen has a 20 percent larger carbon footprint than using natural gas or coal directly for heat.
Blue hydrogen also has a 60 percent greater carbon footprint than using diesel oil for heat. For those unfamiliar, the US Department of Energy says blue hydrogen starts with the conversion of methane to hydrogen and carbon dioxide using steam and pressure in a process that creates a so-called "gray" hydrogen. An additional step creates the blue hydrogen and involves capturing and sequestering carbon dioxide and other impurities in the hydrogen.
It takes substantial energy to produce blue hydrogen, which is typically obtained from burning natural gas. Researchers on the project say no effort was made to capture carbon dioxide during the production of grey hydrogen in the past, and the resulting greenhouse gas emissions were substantial. Blue hydrogen is being positioned as a solution to that problem, but the study has found emissions are still very high.
The study notes that emissions resulting from blue hydrogen are only 9 to 12 percent less than emissions from gray hydrogen. The paper states that blue hydrogen "only works" as a strategy in that it's possible to store carbon dioxide indefinitely without it leaking back into the atmosphere. Study researchers say there is "green" hydrogen that is ecologically friendly, produced from electrolysis, and it could be the path required for a sustainable future.