Direct Air Capture (of Carbon Dioxide)

[KiwiGriff]

 So I'll believe it when the first few dozen million giga tons.
CCS is an excuse to do nothing based on the creation of an as yet unknown technology in the future.
AKA.
Magical thinking.
The amount of air you would need to pump past any industrial type extraction method makes the idea absurd.
Even using natural methods like old growth forestry rely on mind boggling amounts for far too much time .
 

[sidd]

CCS (carbon capture and sequestration) only addresses exhaust from present fossil carbon burn. I am speaking of drawdown.  Besides, CCS has another thread.

Another point is that the interests of equity demand that the nations that burnt the most fossil carbon in the past ought to drawdown the most in future. Alas, that is probably not going to happen.

sidd

[KiwiGriff]

I Apologize  sidd .
I had the term wrong.
I meant the draw down of atmospheric CO2 being impossible with present technology at a palatable  economic cost.

[Ken Feldman]

I Apologize  sidd .
I had the term wrong.
I meant the draw down of atmospheric CO2 being impossible with present technology at a palatable  economic cost.

I think the term that is being used is "Negative Emissions Technology" abbrievated NET. The linked paper provides an overview of the current status of NET.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2016.0447

Negativeemissions technologiesandcarbon captureandstoragetoachieve theParisAgreement commitments
R.StuartHaszeldine,StephanieFlude,Gareth JohnsonandVivianScott
SchoolofGeoSciences,UniversityofEdinburgh,Edinburgh,EH93FE, UK RSH,0000-0002-7015-8394

How will the global atmosphere and climate be protected? Achieving net-zero CO2 emissions will require carbon capture and storage (CCS) to reduce current GHG emission rates, and negative emissions technology (NET) to recapture previously emitted greenhouse gases. Delivering NET requires radical cost and regulatory innovation to impact on climate mitigation. Present NET exemplars are few, are at small-scale and not deployable within a decade, with the exception of rock weathering, or direct injection of CO2 into selected ocean water masses. To keep warming less than 2°C, bioenergy with CCS (BECCS) has been modelled but does not yet exist at industrial scale. CCS already exists in many forms and at low cost. However, CCS has no political drivers to enforce its deployment. We make a new analysis of all global CCS projects and model the build rate out to 2050, deducing this is 100 times too slow. Our projection to 2050 captures just 700 Mt CO2 yr−1, not the minimum 6000 Mt CO2 yr−1 required to meet the 2°C target. Hence new policies are needed to incentivize commercial CCS. A first urgent action for all countries is to commercially assess their CO2 storage. A second simple action is to assign a Certificate of CO2 Storage onto producers of fossil carbon, mandating a progressively increasing proportionofCO2 tobestored.NoCCSmeansno2°C.

I think that the conclusions are pessimistic given that renewables are rapidly replacing fossil fuels, so CCS won't be needed for existing fossil fuel infrastructure.  However, the best IPCC scenario, RCP 2.6, requires the deployment of NET to reduce carbon concentrations in the atmosphere.

One of the promising NETs available today is biomass burning with CCS.  Production of biochar with CCS is also a promising NET that could provide for soil restoration (helping improve that carbon sink) as well as biofuels for industrial feedstocks and aviation.  While those last two aren't negative emissions, they're at least carbon neutral and will allow us to completely transition off of fossil fuels.

[Ken Feldman]

Here's another study of Negative Emissions Technologies (NETs) that indicates more rapid deployment of renewable energy as well as reductions in methane emissions can reduce, but not eliminate, the amount of NETs that need to be deployed.

http://atoc.colorado.edu/~whan/ATOC4800_5000/Materials/CC_policy_renewable.pdf

Alternative pathways to the 1.5 °C target reduce the need for negative emission technologies

Detlef P. van Vuuren   1,2*, Elke Stehfest1, David E. H. J. Gernaat1,2, Maarten van den Berg1, David L. Bijl2, Harmen Sytze de Boer1,2, Vassilis Daioglou   1,2, Jonathan C. Doelman1, Oreane Y. Edelenbosch1,2, Mathijs Harmsen1,2, Andries F. Hof   1,2 and Mariësse A. E. van Sluisveld1,2

Mitigation scenarios that achieve the ambitious targets included in the Paris Agreement typically rely on greenhouse gas emission reductions combined with net carbon dioxide removal (CDR) from the atmosphere, mostly accomplished through large-scale application of bioenergy with carbon capture and storage, and afforestation. However, CDR strategies face several difficulties such as reliance on underground CO2 storage and competition for land with food production and biodiversity protection. The question arises whether alternative deep mitigation pathways exist. Here, using an integrated assessment model, we explore the impact of alternative pathways that include lifestyle change, additional reduction of non-CO2 greenhouse gases and more rapid electrification of energy demand based on renewable energy. Although these alternatives also face specific difficulties, they are found to significantly reduce the need for CDR, but not fully eliminate it. The alternatives offer a means to diversify transition pathways to meet the Paris Agreement targets, while simultaneously benefiting other sustainability goals.

[Tom_Mazanec]

Using Farmland to Address Climate Change
https://www.wibc.com/news/local-news/using-farmland-address-climate-change

The ag research group Indigo has launched what it calls the Terraton Initiative, a decadelong research project with a goal of sucking a trillion tons of carbon out of the atmosphere and into the soil. Indigo's Chris Malone explains harnessing photosynthesis could simultaneously address greenhouse gases and make soil more productive.

[sidd]

Re: Indigo

Called em up a while ago. They seem more interested in buying and selling my grain than soil carbon capture. The person(s) i spoke to promised to return my calls with more information about soil carbon capture, but so far, deafening silence.

They did claim in the press material that they were working with the Rodale institute. I know some people there, will have to drop by next time i'm by Kutztown.

sidd

[Tom_Mazanec]

Cutting climate pollution isn't enough — we also need carbon removal
https://thehill.com/opinion/energy-environment/462609-cutting-climate-pollution-isnt-enough-we-also-need-carbon-removal

Achieving a 100 percent clean economy will require a swift transition to renewables and other zero-carbon energy sources. But we also need to face the reality that meeting the Paris target will require taking carbon out of the atmosphere at massive scale. In part, that’s because eliminating emissions will be very challenging for some sectors, especially the transportation industry and agriculture. Removing carbon from the atmosphere would also bring concentrations down, helping to stabilize the climate at safer levels. So, the push for clean energy must be supplemented by a suite of technologies known as carbon dioxide removal (CDR).

It is not a question of what we’d prefer. It’s a question of insurmountable math.