Sexy/Unsexy, Practical/Impractical: Let’s Talk Atmospheric Carbon Drawdown’s Hype Vs Reality

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The average atmospheric CO2 in September 2022 was 416 ppm, per the Mauna Loa observatory. That’s up from the year before and the year before and the year before. That’s up from about 280 ppm in 1750, almost 50%. And that doesn’t capture high global warming potential atmospheric methane increases, up about 30% since 1983 when it started being measured. This article focuses on the overhyped and overly hoped for silver bullets vs. the realities of what will actually work to start reducing the CO2 and CO2e in the atmosphere.

As always where there is a Gordian Knot, there are people desperate to believe that there is an Alexander who will come along with a sword and cut it, removing the necessity for them to do anything. And where there is desperation, there are people and organizations happy to exploit that for a variety of reasons, from perpetuation of their business models, VC funding, or simply more research grants (the last of which I don’t begrudge in any way shape or form).

And so, on to the sexy nonsense and realistic solutions to carbon and methane atmospheric reduction. These discussions always start in the sexy and practical quadrant, the most hopeful one that gets the most attention and hopefully the most funding. It’s a feel good place to start. Sadly, there isn’t much in that quadrant, just a few things with legs in it.

Let’s start with voluntarily planting a tree. That’s a feel-good story that people around the world can get behind. Some communities have annual events, and it’s nice. Yeah, if everybody planted a tree, things would be fine! Well, no. Not that there’s anything wrong with planting a tree, but everybody would need to plant a lot of trees to make a temporary dent in the problem.

There are already about 3 trillion trees on the planet, per a 2015 study, Mapping tree density at a global scale, published in the journal Nature with overlapping authors. We’ve cut down 3 trillion since we started reshaping the environment to our preferences. It would take a trillion trees to balance out only the last 25 years of CO2 emissions (no impact on methane), and that’s it. We don’t magically get more than that. And it only lasts until the trees fall over. More on the trillion trees later.

There are less than 8 billion people on earth, or 0.8% of a trillion. About 700 million people live in extreme poverty, under $1.90 a day, and they are much more likely to eat any blossoms, fruit, nuts, leaves, and bark and burn the wood of any tree near them than plant new ones. We can safely say that the poorest 25% of people in the world have much bigger concerns than global warming, and so can be excluded from tree planting unless we pay them. Really, it’s more like 0.6% of the population that might plant a tree.

But it’s voluntary. The actual number of people who might plant a tree a year is probably single digits of the population. Call it 0.03% of the needed trillion trees if everyone planted a tree a year. That’s going to take too long.

I love trees. I planted about 12,000 of them one weekend voluntarily. Well, my buddy who owned the land bought the beer and supplied the tractor, tree-planting trailer, and seedlings. I just supplied the aching back from stooping to drop seedlings in the right place for about 20 hours over two days. And I’m a deep, deep outlier, as was my buddy. And the trees may very well have been cleared from the land in full or in part by subsequent owners.

So yeah, we can’t depend on the kindness of strangers when it comes to trees as a solution, as heartwarming as it is to see kids doing that. Climate change will not be solved by voluntary measures or individuals making better choices unless it’s at the ballot box.

Then there’s carbon capture, utilization, and storage. The diagram above is one I developed and iterated a couple of times. It’s the scale-problem diagram. That 50% extra I mentioned in the first paragraph turns into about a thousand billion tons of excess CO2. We’re adding another 35-41 billion tons of CO2 annually.

But our total global carbon usage, including all greenhouses, soda manufacturing, enhanced oil recovery, and things like ClimeWorks amounts to only 230 million tons of CO2 annually. About 80 million tons of that, about 35%, is for enhanced oil recovery, where CO2 is pumped into tapped-out oil wells to get out more oil, which when used as directed results in more CO2 than was put underground. Oh, and about 99.99% of all of the 230 million tons CO2 that’s used today comes from either burning fossil fuels to get it, or from extracting it from underground where it is already sequestered in order to do enhanced oil recovery, or mine tax credits for putting it back where it was found.

Once we get rid of enhanced oil recovery, Equinor’s Sleipner gas facility in the North Sea, and things like it, we’re down to a global CO2 market of maybe 140 million tons. That’s about 0.4% of a single year’s global emissions of CO2. It makes tremendous sense to replace the current CO2 with neutral sources of CO2, but that’s still a rounding error. It is the reason that CCUS edges, barely, into the practical quadrant.

The carbon utilization market is not going to increase sufficiently to make a dent in our carbon emissions. It’s nonsense to think it will. Yet fossil fuel companies especially, as well as VCs and governments — especially governments with significant fossil fuel revenues — are spending billions in the space. The fossil fuel industry needs the fig leaf, of course, as do the fossil-funded governments. The VC industry has a lot of get-rich-quick MBA types, and a remarkable dearth of STEM types, so they are mostly making bad bets with bad information.

The next thing that has a leg in the practical and sexy quadrant is flue carbon capture, grabbing CO2 as it exits smokestacks and cement kilns. We’ve been doing this for industrial CO2 feedstock purposes for over a century. The chemistry is well understood. We know exactly what we are doing, how much it costs, and the like. There’s zero mystery here. It’s edging into the sexy category because once again, a lot of people think we just have to put filters on smokestacks and we’re done — a myth that the fossil fuel industry is happy to perpetuate, with efforts like the Boundary Dam and Petra Nova carbon capture and sequestration debacles, with the latter still being promoted as a success by many of the usual suspects.

Neither was remotely economically viable. Neither captured more than a small percentage of the total coal emissions of the respective plants. Both required lots of extra energy to capture, process, and distribute the CO2. Both were used for enhanced oil recovery, which once again results in more CO2 than is put underground, a complete shell game. That’s why a big part of flue capture is in the impractical quadrants. It’s not a solution, it’s just being sold as one, whether with big budget PR programs from the fossil fuel industry, or by earnest toilers hoping to do well.

But it also has a leg in the not-sexy and practical segment. There are many industrial processes that we don’t have great solutions for, like cement. Manufacturing cement has a step that puts limestone in a kiln and heats it up to make quicklime. A major waste product of that process is CO2. Manufacturing cement is one of the biggest single sources of CO2, and while we can mostly repower the process with green electricity — the clinker cylinder is problematic due to the advantages of a jet of flame, per Paul Martin — we will end up in situations where it’s cheaper to capture the CO2 from the limestone than to use one of the alternative cement chemistries. And we will still need about 140 million tons of CO2 annually.

Capturing the CO2 from processes we can’t get rid of yet and using it in processes that require it makes sufficient sense that it justifies having a leg in the boring but practical quadrant. But I’ll remind you that 140 millions tons of CO2 is a rounding error on our annual emissions. This is an every-little-bit-helps solution, not a shining sword cutting a massive tangle of rope.

And so, on to the overhyped and almost entirely useless quadrant. Pride of place goes to direct air capture. Imagine, if you will, 1.2 miles of fans 8 feet thick and 60 feet high, with liquid dripping through them running 24/7/365, in order to capture a million tons of CO2 from the air per year. Imagine the liquid being heated to 900° Celsius to crack the CO2 out of the carbonate suspension, allowing it to be collected in a second process. Imagine this all being run by natural gas, with two additional carbon capture technologies bolted on to capture the CO2 from burning the natural gas, something which represents 50% of the CO2 captured from the air. Imagine the upstream methane leaks from the natural gas adding another 50% of CO2e, but uncaptured. Imagine the CO2 from the air and the burnt natural gas being pushed underground into tapped out oil wells to liquefy and allow extraction of more crude oil. Imagine that crude oil being processed and burned, leaving more CO2 in the atmosphere than was extracted from it, likely in the range of 4-5x the CO2e.

Imagine a couple of firms getting $250 per ton of CO2 from governments to run this horrific shell game.

Yes, that’s the Oxy and Carbon Engineering Permian Basin direct air capture and enhanced oil recovery project, predictable and predicted by me during my deep dive into the direct air capture firm a bit over three years ago when it was all over the headlines.

You’ll note three things about this. A million tons is a rounding error on a gnat’s ass of our annual emissions, and regardless the Oxy/CE facility will be emitting a lot more CO2e than it captures. The third thing is the requirement for governments to throw absurd amounts of money at the space in order for any business case to make the slightest sense.

Carbon Engineering is only the most egregious of this bad space. ClimeWorks is much more earnest but so vastly out of any perspective of scale that it’s a toothpick lost in a forest. It is getting glowing headlines for starting construction on a facility that will take 36,000 tons of CO2 out of the air every year. 36,000 tons sounds like a lot, but remember the context. That’s 0.036 million tons, when a million tons was already a rounding error on a gnat’s ass. It’s so many orders of magnitude off of the scale of the problem that it’s not worth counting the zeros.

Want CO2 from the atmosphere? Burn a plant and capture the CO2 that that generates. Building Rube Goldberg contraptions to enhance oil recovery and suck dollars out of governmental purses is about as bad as climate tech gets.

Well, until you get to Saudi Aramco’s gas-powered car with carbon capture on the exhaust, an absurd exercise in denying the laws of physics and economics that they proudly roll out at conferences every year, without shame or a care in the world. I’m sure that they know full well it’s complete and utter hogwash, but they are happy to keep up the pretense. People keep coming up with this silly idea, clearly never having thought for two seconds about the chemistry of burning liquid hydrocarbons in the presence of oxygen and the resultant much greater mass and volume of CO2 that results. And they clearly never thought about what the heck the cars with massive balloons on them would do with the CO2. They just think, hey, I can still drive my gas guzzler!

Next let’s talk methane flaring. It was a great hope for a while. Oil and coal facilities that produced a lot of unmarketable methane in various places around the world were just pumping it directly into the air. And methane is a problem, as it has a global warming potential per UN IPCC 6 from 25 to 71 times that of CO2, for 100 and 20 years respectively. Yeah, methane emitted today is really bad for the next 20 years, and just very bad over the longer haul. It gets cycled out of the atmosphere more quickly, hence the reduction compared to that gas.

However, remember when I said atmospheric methane had increased a lot? Well, that was up to about 1,900 parts per billion, or to make the comparison easier, 1.9 parts per million. Multiple 71 times 1.9 and you get 135, which can be roughly compared to the 136 extra ppm of CO2 since the beginning of the industrial revolution.

Yeah, over the coming decades of warming, methane is a problem in the same magnitude as all of the carbon dioxide we have emitted.

(I acknowledge the imperfection of the comparison before atmospheric scientists get on my case too hard. It’s illustrative that it’s in the same order of magnitude, not exactly equal.)

Climate scientists figured this out long before governmental policy makers, of course. Coal was bad, natural gas was good — it had ‘natural’ in its name, right!? — and so natural gas was the ‘bridge’ fuel. The STEM types in the fossil fuel industry knew better, but they didn’t consider it their job to point out the massive negative externalities associated with their profit margins, quite the opposite.

And so now the world runs on a lot more natural gas, and that means a lot more of it being emitted. And so burning excesses off around coal, gas, and oil extraction, processing, and refinement sites became the great hope. After all, if you burn natural gas in the atmosphere it transforms from high global warming potential CH4 to merely the base global warming problem of CO2, as well water and various things like nitrous oxides, one of which is a long-lived chemical with a global warming potential 265 times that of CO2. Ooops.

Flaring is not nearly as effective as the industry claims, emitting five times as much methane as their numbers pretended. Yes, burning fossil fuels in naked flames outside of controlled combustion chambers is deeply inefficient and filthy. Big surprise.

And so, on to the next quadrant, one that’s both boring and impractical. Let’s start with mineral weathering for CO2 atmospheric drawdown. This is literally watching crushed rocks in a field slightly change their chemical composition over months or years. It is less interesting than watching paint dry.

Olivine and magnesite are two of the most commonly cited minerals for weathering, with olivine having the slight edge in publicity and magnesite having catalyst-induced speedier weathering labs. Speedier is relative, of course, with the enhanced weathering taking 72 days instead of much longer.

The proponents of olivine weathering propose that we mine gigatons of the silicate from the tectonic zones where it tends to be abundant, crush and process it sufficiently to have a reasonable percentage of the mineral, transport it for potentially thousands of kilometers and spread it on the ground. They seem oblivious to the energy and carbon implications of a mining and distribution exercise that would dwarf sand and limestone for the global concrete market in order to have a material impact. This is as practical as expecting 8 billion human beings to suddenly change their nature and start liking Morris dancing, Nickelback, fermented yak’s milk, and autocastration.

Accelerated magnesite is worse. The entire space is littered with failures to apply the tiniest of assessments of scale and scope.

ClimeWorks, the direct air capture nonsense-burger cited above, is actually doing a variant of this. It is mixing the CO2 with water and injecting it into basaltic rock formation where it mixes with existing minerals to form carbonates. It’s just as absurd an idea as it sounds with the slightest of thought, yet it continues to get headlines and millions from organizations and people who really should know better, with $650 million in the last round that I’m aware of.

Also in this category is the boring and impractical idea of inspecting the vast majority of the world’s fossil fuel and natural gas site, processing, pipelines, storage tanks, and LNG ships at least annually, identifying leaks and having the thousands of firms that own, operate, or have abandoned these facilities plug the leaks. To give a sense of the magnitude of this task, there are about 600,000 km of natural gas pipelines in just the five largest countries by pipeline length. And like the Nord Stream 1&2 that were blown up in an act presumed to be Russian sabotage, and the Magrreb Pipeline running up from Nigeria to Europe, a lot of them are underwater, making external inspection challenging.

Given that a rather absurd percentage of natural gas has been coming from the rogue state of Russia and its surroundings, and that US shale oil and fracking providers are among the worst in the world in terms of methane emissions, this is a deeply idealistic and utopian vision. The $200 billion liability worth of already or to be abandoned oil and gas wells in Alberta alone should make it clear what a silly idea this is. As others have remarked, the fossil fuel industry is a Ponzi scheme, taking profits from new extraction now and pretending that they will pay for negative externalities with future profits that will never come.

The global average for methane which is delivered for use is 1.5% upstream methane leakage. In natural gas generation, that turns 400 kg CO2 per MWh into closer to 600 kg CO2e per MWh, about 75% of the best coal plants’ 800 kg, ignoring their fugitive coal bed methane emissions. In the USA with its ~3% upstream emissions, that makes natural gas generation over 700 kg CO2e per MWh, or a bit of a wash compared to the best coal generation, although still better than the 1,200 kg of the worst coal generation.

The very small number of absolute best run European sites and pipelines are below 1% upstream leakage, which is the faint hope that Europe is extending for continuing to use natural gas in unnatural volumes despite Russia having cut off — catastrophically with the bombing of the Nord Stream pipelines — the biggest supply. This is also the faint hope of the blue hydrogen industry as well, that somehow everyone along the entire supply chain is going to magically be extraordinary maintainers of vast geographies of equipment. That’s not going to happen without massive lashings of governmental money in one form or another.

And that won’t deal with methane from coal or shale oil deposits. Or from land fills. Or hog farms.

So what will solve the problems of excess CO2 and CO2 in the atmosphere? On to the last quadrant, unsexy but practical. Two of the segments are completely boring, in that they involved not continuing to dig the holes of CO2 and CO2e we’ve excavated in our shared atmosphere.

Avoiding CO2 comes down almost entirely to two headlines: build lots of renewables and electrify everything possible. That’s why those two things are two high-level line items in my regularly iterated and requested The Short List of Climate Actions That Will Work. The presentation based on that material and related discussion has been requested by multibillion dollar fund management groups, renewables conferences as a keynote, and renewables developers looking to energize their professional staff and help them strategize for new segments.

Building lots of renewables is straightforward. Every MWh of renewably generated electricity displaces a MWh of fossil generated electricity. That means elimination of 0.4 to 1.2 tons of CO2. Renewables need supporting transmission and storage, but those are secondary to building enormous amounts of mostly wind and solar. It doesn’t need to have a 90% capacity factor to blow CO2 out of electricity. Nuclear doesn’t hurt, but renewables are a lot faster and cheaper to build.

Electrifying everything possible is pretty straightforward too.

Look for all of the places where rejected energy is leaving energy services (the useful energy that actually does us some good) or electrical generation, look for the thing causing the rejected energy (almost always waste heat from burning fossil fuels), and then replace the fossil fuel energy with an electric device. Gas stoves? Induction stoves. Gas furnaces? Heat pumps. Cars? EVs. Gas as an industrial heat source? Electric arc or resistance heaters. Electricity generation with fossil fuels? Back to renewables.

Every replacement of an energy service directly delivered with fossil fuels makes that energy service vastly more efficient. Electric cars are 80% efficient wind turbine-to-wheel, while internal combustion cars are about 20% efficient well-to-wheel. That’s why my earlier quadrant charts on ground, marine, and aviation transportation all had maximizing electrification of the segment in the practical-but-not-sexy quadrant. Avoiding problems is rarely recognized, rewarded or sexy.

Those 58.1 quadrillion BTUs of rejected energy plummet when electrification is the strong focus. And that means primary energy inputs on the left of the chart plummet as well.

We don’t have to replace all of the oil, gas and coal we consume. We have to replace the useful energy that they deliver, about a third. Renewables to electrified energy services make that easy.

And it makes the 10% of primary energy provided globally by renewables in 2021 a bigger deal than most realize. Because electrification of transportation, heating and the like has been increasing for years, as renewables increase as a ratio of energy, efficiency of direct use of electricity has been increasing as well. This is, incidentally, one of the key things Vaclav Smil appears to either ignore or downplay substantially in his analyses which have been so instrumental in having Bill Gates focus his attention in the wrong places.

Similarly, on CO2e, the answer comes down to four straightforward things: leave natural gas in the ground, change refrigerants, stop burning things and fix agriculture.

Leaving natural gas in the ground comes back to displacing it as a source of energy with renewable electrical generation and electrically powered heating. If we stop pumping it, seal up the wells and rip up the pipelines for scrap steel, the fossil fuel industry’s global 1.5% upstream emissions levels will be irrelevant, because there will be no upstream natural gas. This will take a while, but as the scale of the problem indicated, it’s critical.

The ‘nice’ thing about methane is that if we stop pumping it into the atmosphere, levels will go down relatively quickly as it degrades fairly quickly. We don’t have to try to hasten that process, just stop digging the hole.

Changing refrigerants is, thankfully, much easier. The other day I was in one of my local grocery stores and noticed the cheese display fridge was only a quarter full, and that there were a couple of HVAC techs hovering over it. In conversation, they let me know that they were changing the refrigerants from R-22 with its global warming potential of 1,760 to CO2 with its global warming potential of 1. They were a bit concerned about the requirement to triple the pressure in the system to 150 bar, but then I told them that fuel cell vehicles need 700 bar hydrogen, so they realized that 150 bar wasn’t as bad as they thought. Perspective, it’s not just a subject in art class.

This is what the Kigali Amendment is about, and it’s now globally ratified by pretty much every country that matters including the US and China. It’s amending the Montreal Protocol on Substances Which Harm the Ozone Layer, with replaced CFCs with HFCs. CFCs both harmed the ozone layer and were even worse green house gases than HFCs, so that wasn’t bad, but HFOs and CO2 are much better than HFCs for avoiding global warming. This entire space is number one on the Project Drawdown cost-benefit analysis ranking because it’s relatively easy to make the global shift.  It’s also on my Short List, unsurprisingly.

Stopping burning things might seem redundant. After all, electrifying transportation, heat and making electricity renewable would seem to cover it. But in the CO2e category we circle back to the nitrous oxide N2O, which forms from nitrogen and oxygen in the air in the presence of energy from burning things. And it has a global warming potential of 265 times that of CO2. And it really likes to stay as N2O for a long time in the atmosphere, unlike methane (CH4) which breaks down moderately quickly. Jet engines produce it, so minimizing biofuels in that segment as electrification of longer routes becomes viable is important. Marine engines produce it, so minimizing biofuels in that segment by electrifying everything that can be and tuning remaining engines carefully is important. Pretty much every open flame results in N2O, and we burn a lot of stuff. So we have to minimize that.

And then there’s the biggest source of N2O, agriculture, specifically ammonia-based fertilizers. They are a problem cradle-to-field. They are most made from natural gas with its upstream methane leaks. They are mostly made using steam reformation which binds carbon from the natural gas with oxygen from the atmosphere to make a lot of CO2. And when they are spread on fields, they go through a chemical transformation leading to a bunch of N2O being produced. That means every ton of fertilizer results in 10-12 tons of CO2e.

Our fertilizer use has been fairly flat compared to the growth of our population and GDP due to green revolution optimizations and getting subsistence farmers off of semi-arable land to consolidate it in agribusinesses. But we have to bend that curve down even as our population continues to rise a while longer, peaking between 2070 and 2100, and more people are made more affluent. Thankfully, there are four good wedges that are easy to spread. Keep moving subsistence farmers off of the land and centralizing agriculture into high-efficiency agribusinesses. Shift to low-tillage agriculture which uses less fertilizer. Extend precision agriculture everywhere so that only the most efficient application of fertilizers is done. And spread agrigenetics innovations like Pivot Bio’s enhanced nitrogen fixing microbes globally as rapidly as possible. The last is already cutting fertilizer use on a million acres of corn in the US by 25%, and the co-founder and CEO Karsten Temme told  me that they have a stretch target of 100% by 2030.

The next three are all about enhancing biological uptake of CO2. Unlike methane, CO2 lingers for a long time in the atmosphere, increasing temperatures for 2-3 centuries. So we have to hasten its removal. We’ve covered the senseless panacea’s of mechanical and industrial carbon capture already.

But now it’s biology’s turn. It’s slow and inefficient on a molecule by molecule basis, but there’s an absurd amount of plant matter in the world, and we can increase it. Getting subsistence farmers to stop stripping calories off of everything in site is a start. Getting them off of semi-arable land to let it go fallow is a good follow up. But then industrial-scale tree planting kicks in. Little Johnny or Ayesha sticking a seedling in hopefully the right patch of ground at the local park is heart warming, but intelligently planting 100 million or more trees a week around the world would do a lot more. Massive greenhouses force growing seedlings. Massive drone seedling programs. Lots of machine learning and data science matching seedlings to specific locations.

China is showing us how this works. Just as they deforested their country, they are reforesting it rapidly. They’ve planted over 40 billion trees — 4% of a trillion! — in an area greater than the size of France since 1990, and shifted 60,000 soldiers to tree planting duties. There were mistakes, but not nearly as big as the mistakes of deforestation.

Right now we are planting about 1.9 billion trees a year but cutting down about 16 billion. Sustainably cutting down trees and turning them into durable furniture and buildings is one thing, but most of that is for burning, toilet paper and chopsticks, which is the opposite of sustainable. We have to invert the ratio of planting to cutting.

And wetlands which we’ve paved over at seashores used to be amazing carbon sinks, but now are regularly flooding subdivisions. Time to abandon increasingly at risk former marshes like much of Houston and communities like Cape Coral in Florida and re-wild them. Planned retreat in the face of rapidly increasing climate risks can come with a climate dividend as long as we think about it with a modicum of care.

And finally, soil. Planting trees, letting semi-arable land go fallow, and shifting to low-tillage agriculture allows the soil carbon pathway to kick in. Carbon that’s sucked by plants goes into the roots as much as what’s above ground, and mushroom threads containing the protein glomalin pluck the molecules out and transport them to permanent soil sequestration. It’s a slow process, but if we stop killing the subterranean biomes and allowing more of them to stay intact longer we’ll get a lot more carbon out of the air.

We have the technology for air carbon capture. It’s amazing nano-tech stuff. It comes in tiny packages, is self-assembling into large structures with economic and environmental value and if we leave it alone it will create a green goo that helps bring our planet back into equilibrium. The technology is called plants.

And so, the next quadrant chart of sexy vs practical is in place. It complements the ones on electricity and energy storage, and ground, marine and air transportation. But the series isn’t done. At least one more on residential, commercial and industrial heat is required. Maybe others. Chime in to let me know.