Hydrogen as “green” fuel: a hoax?

Readers have inquired about the possibility of producing hydrogen to be used as a source of energy. After all, it is the most abundant element in the universe, so maybe it is easy to obtain.

Responding to a Japanese inquiry, the International Energy Agency (IEA) sounded somewhat too positive for my taste, even though it is not terribly optimistic. It said: “Demand for hydrogen, which has grown more than threefold since 1975, continues to rise—almost entirely supplied from fossil fuels, with 6% of global natural gas and 2% of global coal going to hydrogen production.”

But just because production has tripled certainly does not assure that this is a positive development. After all, plastic production is now 244 times what it was in 1950, jumping from a mere 1.5 million tons in 1950 to 367 million tons in 2020, with less than 9% recycled. Some environmentalists predict that if plastic disposal continues to grow there will be more plastic than fish in the world’s oceans by 2050. Also, in the USA we use 100 billion plastic grocery bags per year, up from zero in the early 1970s, and requiring 12 million barrels of oil to produce! More is absolutely not always better! In fact, “more” can be downright insane, as these strange cases amply illustrate. It boggles the mind that so much attention is given to fantasies about energy while so little attention is dedicated simply to cutting its use.  So the USA, with 4% of the world population, continues to burn through 15% of the world’s energy!

The IEA document continues on a more pessimistic note, saying: “Producing all of today’s dedicated hydrogen output from electricity would result in an electricity demand of 3 600 TWh (terawatt hours), more than the total annual electricity generation of the European Union.”

There is also some concern about “carbon dioxide, which is emitted from hydrogen production: The IEA notes that production of hydrogen is responsible for CO₂ emissions of around 830 million tons of carbon dioxide per year, equivalent to the CO₂ emissions of the United Kingdom and Indonesia combined.”

Going deeper into the energy use in hydrogen production, Robert W. Howarth from Cornell University and Mark Z. Jacob of Stanford University are even more pessimistic. Their study, the first peer-reviewed one to appear, found that emissions from producing supposedly cleaner “blue” hydrogen are actually  quite high, particularly due to the release of fugitive methane. (3.5% emission rate of methane from natural ga). Total carbon dioxide equivalent emissions for blue hydrogen are only 9%-12% less than for gray hydrogen.

Currently, hydrogen is produced by steam reforming of methane in natural gas (“gray hydrogen”), with high carbon dioxide emissions. Increasingly, many propose using carbon capture and storage to reduce these emissions, producing so-called “blue hydrogen,” frequently promoted as low emissions.

Far from being low carbon, greenhouse gas emissions from the production of blue hydrogen are quite high, particularly due to the release of fugitive methane. Total carbon dioxide equivalent emissions for blue hydrogen are only 9%-12% less than for gray hydrogen, the authors declare. While carbon dioxide emissions are lower, fugitive methane emissions for blue hydrogen are higher than for gray hydrogen because of an increased use of natural gas to power the carbon capture.

More amazing is that they found that the greenhouse gas footprint of blue hydrogen is more than 20% greater than simply burning natural gas or coal for heat and some 60% greater than burning diesel oil for heat.

Even reducing greenhouse gas emissions from blue hydrogen to 1.54%, emissions are still greater than from simply burning natural gas, and are only 18%-25% less than for gray hydrogen.

Maybe the trickiest point is the assumption of hydrogen advocates that indefinite underground storage of their CO₂ emitted is possible. The study points out that this is an optimistic and unproven assumption. They acknowledge that even if the CO₂can be stored indefinitely, the use of blue hydrogen appears to remain difficult to justify on climate grounds.