Recently, I’ve been on a bit of a jag about “blue” hydrogen. I always put it in double quotes because it’s such a PR euphemism. There are many idiotic colors being proposed for hydrogen in the past few years. There’s black hydrogen, sometimes falsely called “brown” hydrogen, which comes from gasifying coal, with 20-35x the mass of CO2 as of hydrogen produced. There’s “grey” hydrogen, which is actually black hydrogen too, made from steam reformation of natural gas with 8-10x the mass of CO2 as hydrogen produced.
Then there are the various pretty colors of the rainbow, “blue” dominant among them. What’s that mean? Well, it’s when you take black hydrogen production, and pretend you are going to slap on something to capture the multiples of CO2, and then put it somewhere forever. And then you can use “blue” hydrogen without remorse, in some sort of happy-happy joy-joy utopia of Mirais and hydrogen hot water heaters.
Except it’s bullshit. Anything which produces multiples of CO2 as hydrogen is just shades of black. “Blue” hydrogen is just black hydrogen with better PR, just as natural gas is just a massive greenhouse gas methane problem with better PR. The fossil fuel industry learned from the accidental branding of methane mixed with various other things as “natural,” and has been trying on various infelicitous phrases since, the most egregious of which was likely “clean coal.” (If there are other candidates, please share in comments).
Most recently, I published a pair of analyses of recently published papers on “blue” hydrogen’s lifecycle CO2e emissions, two articles each on a paper by Howarth and Jacobson (part 1, part 2) and a paper by Bauer et al (part 1, part 2). The biggest difference between the two papers was in regard to upstream methane emissions from natural gas extraction, processing, distribution and handling at the steam reformation plant. I found Howarth and Jacobson’s paper to be something much more aligned with the real world, while the Bauer, et. al paper’s much rosier outlook appeared to apply to a vanishingly small percentage of potential hydrogen projection, and even then had challenges.
But I left one thing out of that analysis. If we actually did start using carbon capture at anything approaching the scale of the problem, where would we put the resultant CO2?
At present about 90 million tons of CO2 are used annually for enhanced oil recovery, where CO2 is pumped underground into tapped out oil wells to liquefy and pressurize them, allowing more of the remaining crude to be pumped out elsewhere. There are only a couple of moderate scale installations that aren’t doing this, and they have other problems. The Equinor Sleipner facility in the North Sea pumps “natural” gas up with too high a percentage of CO2, so they pull off enough CO2 to make it saleable, then pump the excess CO2 back under sea and ground for very large tax breaks, rather than just venting it to the atmosphere. Personally, I think that paying people for cleaning up the trash that they would otherwise leave behind isn’t actually a solution, and it certainly isn’t a solution at scale. The other one is the Shell Quest facility in Alberta, which is actually not doing enhanced oil recovery, oddly enough, but is sequestering emissions from hydrogen manufacturing, and is only sequestering the pittance of a million tons of CO2 annually.
Yes, a million tons isn’t a pittance in and of itself, but it is when you look at the scale of the problem. The annual emissions globally are around 40,000 times as large as the Shell facility, and the historical emissions are over a million times as large and growing.
And here’s the thing. The Shell Quest facility has a limited lifespan. The place 2 kilometers down where it’s putting the CO2 has a total lifetime capacity of 27 million tons, and it’s already used 20% of it (and it will likely become harder and more expensive as pressure mounts toward end of life).
Yes, this ‘amazing’ facility’s total lifetime capacity is a tiny fraction of our annual global emissions, and a much tinier fraction of the historical emissions.
And hence the question. If we manufacture “blue” hydrogen at scale, where exactly are we going to put all of the CO2? There are seven major obstacles to this being a remotely feasible solution, and five of them are purely related to this question.
The first issue is that there is actually competition for accessible sealed underground voids suitable for CO2 sequestration. Strategic reserves of “natural” gas are kept in them today. People with memories longer than that of a goldfish might remember the Aliso Canyon gas leak of 2015. The gas storage facility there is the second largest in the USA, and it sprung a leak which took four months to plug, dumping 97,100 tonnes of methane, the equivalent of 8 million tons of CO2, into the atmosphere over the months before it was plugged, a global warming gas dump bigger than the Deepwater Horizon Leak, but a lot less dramatic looking. They are used today for strategic petroleum reserves as well.
And the hydrogen that’s being touted for this “blue” hydrogen economy is supposed to be stored underground too. While I disagree due to minor issues with the laws of thermodynamics and the reality of economics, many people are claiming that seasonal storage will be hydrogen stored deep underground. And there are the compressed air storage advocates who also want access to sealed underground facilities. The US Department of Fossil Energy — yes, that’s what it’s called, and yes, that’s a problem — is touting massive underground storage of hydrogen as well.
Suitable locations aren’t quite as widespread today as all of that, and as the literature makes clear, easily accessible ones are becoming scarcer.
The second problem is that most of the actually accessible voids were created by emptying them of oil, so preventing EOR is hard. Why do we drill underground? To get stuff out, and most of the places where we took stuff out were petroleum fields. A Globe and Mail headline recently claimed that Canada was missing out on the benefits of enhanced oil recovery, which is a nice way of saying that we were missing a chance to be an even higher carbon economy than we already are. Enhanced oil recovery is a net carbon emitter as oil turns into burnable petroleum products with high CO2 emissions, and hence incompatible with a decarbonized world.
The third problem is that the scale of the problem is in the tens of billions of tons of CO2 annually, a multiple of the tonnage of fossil fuels we extract annually due to the nature of carbon interacting with atmospheric oxygen. Because we are extracting fossil fuels from most of the projected locations for sequestration and then burning them, we are multiplying the mass of the extracted oil, gas, and coal by 2-3 times as we combine oxygen from the atmosphere with carbon from the fossil fuels. It’s really hard to pretend that we are going to put 2-3 times the mass of CO2 underground as the mass of fossil fuels we extracted without intentionally ignoring physics.
In the first half of this two-parter, it’s already becoming clear that the magnitude of the problem is vastly bigger than anything we can expect carbon capture and sequestration, for hydrogen or any other purpose, can possibly accommodate. In the second half, we’ll flesh this out with more challenges which make it abundantly clear that this is not a solution, but a policy failure of staggering proportions.