As I laid out in my previous post, the state of climate change is not good. We are woefully behind schedule for hitting our 2 degrees C temperature target for warming above pre-industrial levels and any ambitions of halting warming at 1.5 degrees C are all but dead. So where’s the panic? Or at least why are most of our policy-makers espousing the view that climate change can be addressed without some level of economic upheaval.
Well as I alluded to in part 1 of What Policymakers Aren’t Telling You About the State of Climate Change, geo-engineering, combined with the concept of negative emissions, has become a deus ex machina for climate policymakers (as well as carbon taxes but we’ll get into that in another post). Now there are many negative emissions technologies (NETs) for policymakers to choose from including direct carbon capture (DAC), enhanced weathering (EW), and afforestation & reforestation (AR), but here we will be focusing on bio-energy with carbon capture and storage or BECCS as it seems to be the only NET that is remotely feasible when scaled globally. Solar radiation management is another popular form of geo-engineering, however, SRM only affects albedo, a measure of how much sunlight is reflected back into space, and not the concentration of greenhouse gases (GHGs) in the atmosphere, so it isn’t a permanent or ideal solution.
As the threat of climate change has become more salient, it appears that our policymakers have started to take the view that if the findings from climate scientists & economists are not consistent with the current economic paradigm, why not just adjust the findings so they are consistent with the current economic paradigm by extending the time horizon for climate change mitigation policies.
Now we aren’t talking about cooking the books or anything nefarious, but if we assume that in the upcoming decades NETs can be implemented at a global scale, then in theory we can “overdraft” our carbon budget in the near term and pay back on our loan to the climate in the future so by the end of the century warming stabilizes at 2 degrees C. From a scientific and economic standpoint this is perfectly reasonable (if we don’t cross any climate tipping points in the meantime), there are many instances where it is not only acceptable but proper to incorporate “ future advances in technology” into your analysis; Andrew Kennedy’s “Wait Equation” for traveling through space is a good example.
Policymakers can factor these negative emissions/geo-engineering strategies into their integrated assessment models (IAMs) and develop mitigation plans based on this underlying assumption that these NETs are in fact possible and will be implemented. Assuming BECCS is deployed from 2020 onwards and significantly ramps up in the 2040s & 50s, IPCC scenarios representing the lowest cost cases for emissions reduction typically require 20 Gt of CO2 to be sucked out of the atmosphere yearly by 2070; for context present-day emissions are about double that or 40 Gt of CO2 emitted annually.
So is it reasonable to assume that these negative emissions technologies are not only cost-effective but actually are plausible purely from an engineering standpoint, given the time & resource restraints? No. At least that’s the point of view of the engineer writing this article that you are reading right now. This is also the point of view taken by Kevin Anderson the mechanical engineer whose research underpinned most of the arguments I made in my previous post; additionally, here is a report written by a group of 15 independent researchers that stress that reliance on NETs as the predominate mitigation strategy for addressing climate change could become “a dangerous distraction.”
So what is BECCS? Well for a full explanation of how BECCS work’s I would suggest reading this article, but here’s the short version. To start off, society would have to plant approximately 300 to 900 mega-hectares of biomass (i.e. trees and bushes) across the globe; that’s equivalent to planting a forest 1-3 times the size of the Indian subcontinent! Then all those trees would have to be cut down and shipped around the world where the existing carbon infrastructure would use this new biomass as fuel, replacing coal, oil, and natural gas wherever possible (this all has to be done while emitting ZERO-net emissions by the way)
Secondarily, all the CO2 emissions produced by burning this biomass has to be captured, if not this entire process would be carbon neutral not carbon negative. Then all the captured carbon must be stored away (presumably underground) in a fashion that would guarantee that the CO2 would never ever leak back into the atmosphere, or at least not for the next couple of millennia or so.
Lastly, this entire process, from planting the trees to capturing and storing the CO2, would have to be repeated EVERY year, until total annual global emissions from all other sources are net-zero. And this scenario assumes that all of this infrastructure will be up and operational by the middle of the century. There may not even be enough land out there to plant all the trees in the first place, given the fact that we still need enough farmland to feed the 7 billion people living on this planet.
To complicate matters even further if you decided to plant some of these trees in a snowy place like Siberia you could actually end up accelerating the warming of the planet. Snow reflects sunlight back into space because it’s white but tall dark coniferous trees absorb sunlight transforming that energy into heat (in essence you’re lowering the planet’s albedo). And there is a whole host of other problems ranging from putting stress on the global water supply (because you know, trees need water too) to actually finding enough suitable underground reservoirs to store the billions of tonnes of CO2 that will be captured in the BECCS process.
Now this wouldn’t be that big of an issue if just one or a few scenarios required the use of BECCS in order to halt climate change, but seemingly every emission reduction scenario calculated by these IAMs requires some form of global biomass generation and subsequent carbon capture & sequestration (107 out 113); and the ones that don’t assume that global emissions for GHGs peak in…. 2010, so unless there is a time-machine out there that I don’t know about this is utterly ridiculous. Our reliance on BECCS as the overarching climate mitigation strategy has stemmed from our governments’ insistence that the current economic paradigm must be protected, regardless of the cost. This is also what policymakers aren’t telling you about the current state of climate change.
The underpinnings of all our commitments and all our pledges to reduce greenhouse gas emissions assume, incorrectly, that these geo-engineering technologies are feasible and economical to implement. As a society, we have allowed our elected leaders to promote this friction and that must stop. Is there some role for NETs in our global mitigation strategy? Yes; many sources of GHG emissions will be very difficult, if not impossible to decarbonize, agricultural-based emissions come to mind as a prime example. So our lawmakers need to appropriate the money necessary to seriously analyze the efficacy of these technologies; however, we cannot use the concept of negative emissions as an excuse to delay action.
There are going to be some tough trade-offs that we, as a society are going to have to grapple with; politicians are going to have to explain to their constituents that if we are really going to be serious about addressing climate change we will all personally have to make some sacrifices. That is what happens when you procrastinate and refuse to tackle any issue of this much importance for multiple decades. But deluding ourselves with this fiction that biomass and carbon capture & storage can cure all of our ills is not only irresponsible it will ultimately lead to our ruin. Right now BECCS is our plan A and there is no plan B. That is absolutely unacceptable.
