This is a preprint from my column ‘Cool Fuel’ in Cold Facts Magazine by the Cryogenic Society of America.

I was ready to write to you about the awesome green beauty of a 454.6 nm argon laser and what it does to the hydrogen molecule when a friend sent me an article from the New York Times by Hiroko Tabuchi, “For many hydrogen is the fuel of the future. New research raises doubts.” The article is ‘based’ on a recent journal publication, “How green is blue hydrogen” by Robert Howarth and Mark Jacobson who are researchers at Cornell and Stanford Universities. As the title suggests, the New York Times piece (unlike the underlying journal publication) is generally negative about hydrogen just as multiple federal legislative bills concerning hydrogen are in the final touches of Congress. If I took the time to respond to every negative hydrogen opinion in the press I wouldn’t have time for research anymore. But I have yet in my career to see an article emphasize so many of the negative biases at once, in such a high profile venue, at such an in-opportune time. So, we need to have a talk about bias and the colors of hydrogen.

Many of you may be confused about this talk of hydrogen ‘colors’. No worries. Hydrogen is still the same colorless, odorless, tasteless gas, that comprises 74% of the universe. But not all hydrogen is created equally. A color designation scheme was invented a few years ago to color-code hydrogen based on the amount of carbon dioxide (CO2) emissions during production:

  • ‘Black’ hydrogen is produced from coal or oil with the highest associated CO2 emissions.
  • ‘Gray’ hydrogen is produced from methane with steam reformation resulting in approximately 7.2 kg CO2 for every kilogram of hydrogen produced (this is the color associated with the vast majority of industrial hydrogen produced over the years, which nearly entirely go to petroleum refining and ammonia fertilizer production).
  • ‘Blue’ hydrogen is produced with CO2 emissions but those emissions are captured and sequestered in some way, like geological storage or concrete.
  • ‘Pink’ hydrogen is produced with no CO2 emissions but from a nuclear reactor and the associated nuclear waste (for what it’s worth hydrogen will fluoresce a beautiful pink in an arc lamp, just about the only color hydrogen ever actually is).
  • ‘Green’ hydrogen is produced with no CO2 emissions, typically from electrolyzing water via renewable energy like wind or solar.

‘Turquoise’, ‘brown’, and an entire rainbow of other colors are out there, you get the point.

Howarth and Jacobson’s much needed research article considers the practical global warming emissions associated with blue hydrogen that would otherwise allow this form of hydrogen to be comparable to the zero CO2 emissions of green hydrogen. They found that, no surprise, sequestering the CO2 produced with gray hydrogen is challenging, and that methane leaks from the processes generally offset the net global warming improvements. Although critical of blue, this is by no means a general rebuke of hydrogen as a fuel. The authors specifically say in the conclusions, “Society needs to move away from all fossil fuels as quickly as possible, and the truly green hydrogen produced by electrolysis driven by renewable electricity can play a role.”

Hiroko Tabuchi’s New York Times piece, however, uses the small truths from the journal article to weave a tail against hydrogen in general that a friend who is an editor described as a “hit job”. Here are some of the embedded biases used in the article that are common in anti-hydrogen groups:

  • The article generalizes hydrogen, with almost seeming intent to conflate the different colors. ‘Blue’ hydrogen isn’t specified until the fourth paragraph before quickly shifting back to hydrogen generally.
  • ‘Green’ hydrogen, which is a primary focus of the journal article, current legislation, and most (in my experience) gas company efforts, isn’t mentioned until the 17th
  • When discussed, ‘Green’ hydrogen is placed in a negative light, “Today, very little hydrogen is green, because the process involved — electrolyzing water to separate hydrogen atoms from oxygen — is hugely energy intensive.” Thermodynamics, my passion to teach, shows us that energy conversion requires energy for starters, and since hydrogen has a lot of energy it is therefore intensive. That’s why hydrogen has value, it is the primary energy driver of chemistry. This certainly sounds like a bad thing when said the way the author’s bias intended.
  • “For the foreseeable future, most hydrogen fuel will very likely be made from natural gas through an energy-intensive and polluting method…” Green hydrogen electrolyzers are following similar growth trajectories as wind and solar, just two decades later. Underestimating the pace of technological change was emphasized in the journal article for prior dismissals of green hydrogen but seems to have been ignored by the New York Times reporter.
  • “In most places, there simply isn’t enough renewable energy to produce vast amounts of green hydrogen.” I live in the heart of a place that does have enough renewable energy in the Pacific Northwest. While not ‘most places’, the entire surface of the ocean is most places and has enough renewable energy to produce vast amounts of green hydrogen from floating wind turbines, as one example.
  • Falsely associating a leading hydrogen advocacy group, the Hydrogen Council, with oil companies, “The Hydrogen Council, an industry group founded in 2017 that includes BP, Shell, and other big oil and gas companies, did not provide immediate comment.” By my count 9 of the 41 steering members of the Hydrogen Council are based in the oil and gas industry. 3/4 of the Hydrogen Council steering members not being oil and gas companies sure sounds like a different story.

What is clear, the New York Times piece is trying to con people away from all hydrogen, even green, at a critical time. Why reporters and editors would feel the need to gatekeep and construe the hard efforts of many researchers and organizations like this is beyond me. We will not solve the climate crises without clean molecules. We will not have clean molecules without clean hydrogen. It’s universal law.

Regardless, the damage is done. Most of my friends on the fence about hydrogen shared this, or a derivative of the journal article with me within days of publication. Many, even those in academic spheres, didn’t read beyond the press title or the journal article carefully to see the bias as we’re all in a hurry these days. The irony is that if you replace ‘hydrogen’ with ‘electricity’ in the press article, it could’ve been straight out of the 2000’s regarding the greening of our electric grid.

For what it’s worth, all you’ll see is green hydrogen in my CSA short course or on my blog, because that is the future I’m training professionals for. But you won’t see me slamming the door shut on ‘blue’ hydrogen either. The green hydrogen route with liquefaction that I’ve been pushing for over a decade now was long ridiculed using many of the same arguments as those against blue hydrogen above. Both the press and journal articles make the same mistake of casting as absolute extrapolations of the status quo without consideration for the limits of physical law. Those limits of physical law mean that if something is not forbidden, we will eventually find a use for positive means. What we really need is more research on ways to produce hydrogen (of any color) more efficiently with less global warming. Until we finally fund hydrogen research equivalently with batteries and electricity, all of this negative bias about hydrogen is turning my hair gray; no, let’s call it silver.