In the fantasy of the zero-emissions electricity future, there will either be regular devastating blackouts, or something must back up the intermittent wind and solar generation. In New York we call that imaginary something the “DEFR” (Dispatchable Emissions Free Resource). But what is it? Nuclear has been blocked for decades, especially in the blue jurisdictions that are most aggressively pursuing the wind/solar future. Batteries are technologically not up to the job, and also wildly too expensive. That leaves hydrogen. Anybody with another idea, kindly speak up.
I’ve had several posts discussing the question of whether hydrogen could do this job, for example this one on February 14, 2024, and this one on July 20. Those posts focused on the initial cost of making hydrogen by electrolysis from water. That cost turns out to be a multiple of the cost of producing natural gas by drilling into rock (for comparable energy content). From time to time I have alluded to other potential problems with having hydrogen replace natural gas in the electricity system — things like leaks, explosions, and the need for an entire new infrastructure of pipelines and trucks to carry the stuff and power plants to burn it. But until now I haven’t found a detailed study on just how bad these additional problems might be.
Now comes along an August 18 article in a peer-reviewed journal called Energy Science & Engineering, with the title “A review of challenges with using the natural gas system for hydrogen.” The article was linked on August 23 by Paul Homewood at the Not a Lot of People Know That site, and then further linked by Watts Up With That on August 24.
The lead author is a guy named Paul Martin. Unusually for an article in such a journal, no academic affiliation is given for Mr. Martin. Looking him up on LinkedIn, I find that he is not an academic, but rather identifies himself as a “chemical process development expert” who has spent “years in industry,” and is currently with Spitfire Research, Inc., which in turn states that it specializes in “consulting for a decarbonized future.” Mr. Martin then identifies several of his co-authors on the paper as a “team of people at the Environmental Defense Fund.” That information may well color your perception of what Martin, et al., have to say in their paper.
The gist of the paper is that the existing natural gas infrastructure of storage facilities, pipelines and power plants absolutely cannot be repurposed for use by hydrogen; and indeed, there does not exist any practical way to transport and combust hydrogen safely on a large scale. And the effort to even try would be wildly costly. I’ll just give examples of some pithy quotes from the paper:
- Pipeline deterioration and cracking: “Recent, extensive testing of typical pipeline materials in Europe demonstrates both acceleration of fatigue cracking and reduction in fracture toughness when hydrogen is used, but the impacts vary widely depending on the material.36 Welds and their heat-affected zones, as well as manufacturing or fabrication defects in the pipe increase vulnerability by serving as crack initiation sites.37”
- “Blending” hydrogen into natural gas is not a solution: “Even with small percentage admixtures of molecular hydrogen in high pressure natural gas pipes made of high-yield strength carbon steels it is expected that considerable acceleration of fatigue cracking, by as much as 30-fold, will occur with fracture resistance of the piping material reduced by as much as 50%.34”
- Lower volumetric energy density of hydrogen means that pipelines and storage facilities would need to be tripled in size to transport the same energy content: “Switching the gas system to pure H2, with an energy density per unit volume roughly one-third that of a typical pipeline gas; therefore, would result in a reduction in “line pack” storage to one-third of the present value if storage pressure and volume are kept constant (Figure 5).49 If pipeline design pressures must be de-rated to accommodate the added risks associated with hydrogen to the pipeline materials of construction (as discussed in Section 3.2), a further reduction in the line pack would be expected.”
- Existing consumer appliances that use natural gas are unsuitable for hydrogen: “H2 is also more explosive, ignitable, burns hotter, and the flame is faster with lower visibility than CH4; these characteristics yield higher safety risks. The significant differences in properties between typical natural gas mixtures and H2, therefore, necessitate changes in the design of burners and burner management systems to achieve comparative levels of safety, which must then be certified (Figure 6).17, 67”.
- Even with new consumer infrastructure, hydrogen would be much more dangerous for consumers than natural gas: “A quantitative risk assessment (QRA) was carried out in advance of a planned trial of pure H2 in a residential gas distribution system in the UK.18 The report concluded that even if the homes were fitted with appliances designed and certified for use with H2, the risk of damage and injury due to fires and explosions would increase in frequency and severity.”
- Conclusion: “Overall, while repurposing the natural gas system for use with hydrogen may, at first, seem appealing, the limited practicality, risks, and data gaps strongly suggest that like-for-like gas substitution provides limited benefits for increased risks, even if major technical and economic hurdles are overcome.”
After all that, you might think that these authors would have given up and decided that we’ll just have to stick with natural gas. But no, remember that these are anti-carbon crusaders allied with the Environmental Defense Fund. Here is the final paragraph of the Conclusion:
[C]ontinuing to rely on natural gas is also not a viable option for addressing the climate crisis. Considering its physical and chemical properties, hydrogen is not an effective decarbonization tool for use in homes and buildings. For any decarbonization strategy, it is critical to determine if a fuel is in fact needed, and to compare with potentially more effective options such as direct electrification using renewably generated electricity.
We’ll just have “direct electrification using renewably generated electricity.” I guess that means, put solar panels on your roof, and when the sun sets the air conditioning and heat go off and the lights go out. It’s the gkam solution without the undisclosed nighttime grid hookup.
Perhaps the most valuable part of the article is the EDF revealing that it stands ready to oppose the buildout of hydrogen infrastructure just as vigorously as it opposes any natural gas infrastructure. Even if zero-emissions electricity were important and hydrogen were a good solution to get there, EDF would be ready with a litigation barrage to block it.
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