Carbon Management
Mitigation vs Removal
CDR News
This section will be filled with the week that was in carbon dioxide removal (CDR). Over the holidaze the wires were thin but here are a few stories:
BCG pledges partnership with DAC company to be carbon neutral by 2030
Speaking of DAC, here's a recent expose
For you nerds, incremental progress in catalysts for post-combustion capture and utilization
Nerd rating: 1 (1 to 10 scale on how in the weeds the post will get)
This rating system was shamelessly stolen from Chris Nelder
For these first few posts, I want to give my non-CDR familiar readers a solid background of the space, helpful analogies, terms, distinctions, and justifications. We have plenty of time to get into the technical stuff.
The Golden Analogy
Anyone who has worked or followed in CDR and climate long enough has heard some version of this analogy. A bathtub filled with water represents the amount of carbon dioxide in the atmosphere, the spigot is the current emissions, the plug is carbon dioxide removal. To prevent climate change's most extreme negative outcomes (overfilling the bathtub and flooding your bathroom, seeping it into the basement, black mold, death of your whole family), we need to stop both the spigot and pull the plug.
Turning off the spigot reduces current emission by fuel switching, becoming more energy-efficient, and capturing carbon as it is emitted. Pulling the plug is net removal of carbon from the atmosphere. Stopping the spigot is critical, but by working at the problem from both directions and using all the tools available, we can keep the more extreme outcomes from occurring, and hey, it’s working.
And to be very loud and very clear, we need to turn off the spigot and pull the plug. We cannot carbon remove ourselves to net zero. We cannot line up 100000 DAC facilities and take out what we put in. We need renewables, nuclear, electric vehicles, batteries, demand-side response, energy efficiency, hydrogen, NG with CCUS, all forms of CDR, and every other technology that can help us get to net-zero by 2050. This isn't an either/or solution, it is a yes/and solution. There are resource constraints applied to each technology, but that's where policies meet markets. If we can set our policies to incentivize rapid decarbonization, the best solutions win out in the long run. At least, that's how we hope and need it to work.
Carbon Management: Mitigation vs. Removal
Much of my writing on this will be diving into the buzzword and acronym hell that is the policy world. Carbon management policy is not spared, and I would argue it's the worst of the lot.
Let's start from the top and work our way down. Carbon management is an umbrella term that comprises two fundamental ideas: mitigation and removal.
Mitigation
Carbon mitigation is fully and wholly about reducing emissions currently being produced. Examples include fuel switching: retiring coal-fired power plants for lower-emitting alternatives (solar, wind, nuclear, hydro, etc.) or switching from an internal combustion engine (ICE) to an electric vehicle. Another form is of mitigation is energy efficiency, like making an industrial process use less input energy for the same resultant product.
Notably, I include carbon capture and utilization and storage (CCUS) as a carbon mitigation technology under specific contexts. This technology is deployed for current emission reductions in a relatively high CO2 concentration source, like the exhaust stream of a power-producing natural gas plant or industrial capture in a steel facility. This can be compared to direct air capture (DAC), which captures carbon from a very low concentration source, the air. This difference is noted in the terms point-source capture and ambient capture. The scale is essential, as Dave Roberts notes,“ …it is always going to be easier to pull CO2 out of an exhaust stream, where it is concentrated (roughly 1 molecule out of every 10), than out of the air, where it is highly dispersed (roughly 1 molecule out of every 2,500).” Although direct air capture and combustion capture are similar in their method, the difference in the role is important to note.
The utilization and storage portion of CCUS is downstream of both CCUS and other forms of carbon capture and so not unique to the mitigation world.
There are a staggering number of carbon mitigation strategies, at macro and microscale, both hardware and software, and across the industrial, manufacturing, transportation, and power sectors. And all will play a role in fully decarbonizing the global economy.
Removal
We will meet many of those mitigation technologies throughout our CDR journey (For example, as we look at what powers removal systems like direct air capture). Still, for the most part, this writing will focus on the other side of carbon management, the removal aspect. Removal is a literalism: removing carbon dioxide straight from the atmosphere. Often you will hear of removing "legacy emissions" these are the molecules of CO2 that got our planet to the current levels of CO2 concentrations and our current predicament. They are the carbon legacy of humans from the Industrial Revolution onwards.
Carbon removal technologies fall into two broad categories, nature-based and engineered. We will do a deep dive into each technology this year, but for some quick introductions.
Nature-based:
· Re-forestation (re-plant old or damaged trees)
· Afforestation (plant new trees)
· Forest management (thinning understory)
· Soil carbon management (cover crops)
· Seaweed cultivation (Ocean removal from seaweed captured carbon)
· Microalgae cultivation (Same as above, just with microalgae)
· Ocean Management (Restoration of carbon removing ecosystems, like mangroves)
Engineered:
· Direct air capture (DAC)
· Enhanced mineralization (certain minerals react with the CO2 in the air and "capture" it)
· Bioenergy with CCS (BECCS = burning woody biomass and capturing the emissions)
· Biochar (Aka black carbon, overlaps with nature-based solutions, used for increased crop yields)
· Ocean alkalinity enhancements (As alkalinity goes up, so does the carbon removed)
· Coastal Enhanced Weathering (Mineralization, but for the beach)
This list is non-exhaustive. There is an overlap between nature and engineered solutions. There's a distinction to be made between ocean-based CDR and terrestrial CDR. Not everything fits into a box perfectly, but humans need some structure, so this is a rough estimation. For those that enjoy crude SmartArt, below is a hierarchy of terms and examples.
Alright, you've captured your carbon, great. But how do you get it to where it needs to go, and what do you do with it when it gets there?
These are the transportation and utilization or storage bits of carbon management. For the sake of your attention spans, those will be their own introduction newsletters that have their own technologies, acronyms, and nuances. It's Russian dolls all the way down.
Next week we'll answer the question of why we even need CDR? Sure the bathtub needs to be drained, but how soon? How fast? And why can't we just reduce our emissions to combat climate change?
Next week: CDR is VIP
Resources
Learn
http://climatechangeacademy.com/courses/carbon-removal
Follow
https://twitter.com/carbon_180 for policy
https://twitter.com/Climeworks for business innovation
https://twitter.com/_david_ho_ for academic excellence