Topic: BECCS, Carbon Capture and Storage; DAC; CDR

Don’t deploy negative emissions technologies without ethical analysis. Nature. Sep. 19, 2018.

Climate policy advice is being undermined by value-laden choices over risky mitigation strategies, warn Dominic Lenzi and colleagues.

Sucking carbon out of the air won’t solve climate change. David Roberts, vox. Jun. 14, 2018.

Bioenergy with Carbon Capture and Storage Approaches for Carbon Dioxide Removal and Reliable Sequestration. Proceedings of a Workshop—in Brief. National Academy. 2018.

Bioenergy with carbon capture and storage (BECCS) is a technology that integrates biomass conversion to heat, electricity, or liquid or gas fuels with carbon capture and sequestration. BECCS could provide a significant portion of the global energy supply if deployed to its theoretical maximum feasible amount. The future role of BECCS is a subject that divides researchers as estimates of potential future biomass supply vary widely due to differences in approaches used to consider factors such as population development, consumption patterns (e.g., diet), economic and technological development, climate change, and societal priorities concerning conservation versus production objectives. Nevertheless, many integrated assessment models use large-scale deployment of BECCS in scenarios that limit climate change to below 2°C. 

On October 23, 2017, the National Academies of Sciences, Engineering, and Medicine convened a third meeting in Irvine, California, to explore the state of knowledge and research needs related to the potential of BECCS as a CDR approach. Invited speakers gave an overview of biomass production pathways and capacities, implications of various feedstocks, advanced conversion technologies, and capture and storage strategies. Presenters at the workshop also discussed cross-cutting issues that include life cycle impacts of large-scale BECCS deployment, policies and incentives for the implementation of these approaches, and social acceptability barriers. The workshop was preceded by an introductory webinar on October 16, 2017, where invited speakers provided a primer on the prospects of BECCS for negative emissions capacity; the capacity for biomass to meet stationary generation and transportation fuel needs; and the status, challenges, and costs of implemented bioenergy and biofuels. This publication summarizes the presentations and discussions from both the webinar and workshop.

The Need for Carbon Removal. Holly Jean Buck, Jacobin. July 24, 2018.

Massive removal of carbon from the atmosphere — also known as negative emissions, carbon drawdown, or regeneration — could be a cornerstone of either dystopian or radically utopian futures. Some of the dystopian ones are well known: vast conversion of land to plantations for biofuels with carbon capture and storage, displacing people from the land, destroying habitats, and spiking food prices. 

But given what we know about climate change in 2018, it’s not enough to protest against dystopian versions of carbon removal. Too much warming is already locked in. We need a radically utopian way of removing carbon. 

If we buy into thinking of carbon removal technologies as substitutes for reducing carbon output, then industrial interests have already won: they have set the narrative and the framing, where carbon capture exists so that they can continue to emit. But we should demand more from these technologies. 

Industrial carbon capture technologies could instead be used as an extension of decarbonization — mitigation to get us to zero, and carbon removal going a step further to take emissions negative and address some of the climate impacts already being felt. 

It won’t be easy. But climate science suggests it’s a challenge the Left must take up. 

Carbon Removal 

Climate change has already warmed the planet over 1°C relative to pre-industrial levels. Paradoxically, cleaning up the air pollution that’s currently masking some of the global warming in the pipeline would raise temperatures another 0.5 to 1.1 degrees. 

This means that if we waved a magic wand and suddenly (1) stopped using fossil fuels, and (2) cleaned up air pollution, we would already be breaching 1.5°C — the amount of warming that most climate advocates have argued for. 

The carbon budget is not an exact science, but it seems we are hovering at the point where 1.5°C of warming is locked in by what has already been emitted. Put differently, the most recent scientific evidence suggests we have zero to five years before every additional ton of carbon dioxide emitted would need to be compensated by a ton of negative emissions to stay below 1.5°C. 

In fact, the scenarios used in the fifth Intergovernmental Panel on Climate Change (IPCC) report rely on massive amounts of negative emissions to curb warming to 1.5°C, primarily via a method known as bioenergy with carbon capture and storage (BECCS). This led a team of modelers to try and see what it would take to achieve 1.5° without BECCS. 

Even a scenario where renewables, electrification, and energy efficiency were aggressively pursued — and 80 percent of meat and eggs were replaced with cultivated meat, flying was reduced, and tumble dryers were eliminated — could not eliminate the need for carbon removal. This scenario still required about four hundred billion tons (Gt) of carbon dioxide removed via reforestation. Reforestation sounds great and green, but it also has the potential to result in dispossession, conflict over land access, and worsened livelihoods for smallholders. 

What about achieving a slightly less ambitious goal of 2°C? Two and 1.5 degrees might not sound all that different, but they are. The difference is one that threatens entire unique coral ecosystems, the homes of five million people (including entire countries), and high increases in the frequencies of extreme events. 

Rapid mitigation could still curb warming to 2°C without the use of negative emissions technologies. But that window is closing fast. If near-term emissions reductions follow the trajectory laid out in the commitments nations made under the Paris agreement, by 2030, 2°C scenarios will also depend upon negative emissions. 

That is, in the next decade, we would have to vastly exceed the Paris promises to not depend upon negative emissions. 

We aren’t even making much progress towards these Paris targets, which if achieved would still produce 3°C of warming — an amount widely agreed to lead to massive disruptions. This is why negative emissions have become such a useful device for the models. 

By the end of the century, scenarios for 1.5°C or 2°C envision pulling out ten billion tons (10Gt) per year. For comparison, current levels of emissions are around forty billion tons of CO2 per year. So 1.5°C means not just zeroing out those forty billion tons, but then working to extract another ten billion on top of that to be net-negative. This would require scaling up current carbon capture and sequestration efforts a thousand-fold. 

Negative emissions help maintain the narrative that although time is running short, we can still stop catastrophic global warming if we act now. Once we understand that this inventive arithmetic has been employed to “solve” for 1.5, what do we do? 

Assuming there will be a complete about-face that puts us on a course towards 100 percent renewables, massive lifestyle changes, and drastic land use change for afforesting millions of hectares in the tropics within the next ten years strikes me as not only magical thinking, but thinking that puts many at risk of great suffering. 

Alternately, accepting that the earth will warm more than 1.5°C means accepting the loss of the world’s coral reefs and the half billion people relying on them, as well as other harms to communities living on the front lines of climate change. 

So we need to ask: is there a form of massive carbon removal that could be put towards socially just ends, pulling carbon out of the atmosphere as a form of collective social good? Can it work as an outgrowth of energy democracy? For if such a collection of technologies, practices, and institutions can exist, we should try to build it. 

Notably, carbon removal at what I’ll call climate-significant scale should not be thought of as a magic wand to wipe carbon away either. For one thing, it will not compensate exactly for emissions. The ocean, for example, currently takes up close to half of the carbon humans emit, and it’s possible that if carbon was removed at a large scale from the atmosphere, the oceans would then give off carbon, perhaps replacing half of the carbon that had been removed. 

The prospect of carbon removal is fraught with complexity, and even peril — all of which we have to talk about. 

The Necessity of Geological Sequestration 

The best way to remove carbon immediately is through “natural climate solutions,” which employ nature’s processes to store carbon in ecosystems. Sequestering carbon in soil, restoring forests and planting new ones, and protecting wetlands can store carbon. These can forestall some amount of warming, in addition to other benefits for both humans and the environment. 

Yet while it seems intuitive to simply let nature take up the carbon, carbon was put into the atmosphere unnaturally, and the available scientific evidence suggests ecosystem-based solutions simply don’t scale well enough to contend with the sheer amount of carbon that has been dumped into the atmosphere. 

Pursued vigorously, reforestation and soil carbon sequestration could each remove a few gigatons per year — for a while. After a few decades, a forest planted to remove carbon reaches a plateau where it becomes saturated and can’t remove any additional carbon, like a bathtub filling up, at which point the already-absorbed carbon must simply be held indefinitely. 

Similarly, a farm that has transitioned to regenerative practices to store more carbon in the soil can only remove additional carbon for a few decades. Moreover, forests can be ravaged by epidemics or fires, resulting in the sudden release of their stored carbon, which means they are vulnerable to global warming itself. 

So while these projects can do important work in the near future, we also need to supplement these one-off, land-based carbon removal projects with systems that can continuously remove carbon and store it reliably over centuries — that is to say, with industrial carbon capture with geological sequestration. We need to build systems that capture carbon emissions from sources like power plants or factories, or even from ambient air, and transport it to underground reservoirs where it can be stored. 

There are major technical and social obstacles to this. But these industrial systems for geological storage, used together and sequentially with natural carbon removal, could help ease the path to a climate-stable world. 

Carbon capture and storage (CCS) technology is not a new technology....

Can we remove a trillion tons of carbon from the atmosphere?  Nick Breeze, Ecologist. May 3, 2018.

'Remove', 'sequester', 'lock-up'. Call it how you like, but to stabilise our climate and surpass the Paris Agreement, we really need to be thinking about storing hundreds of billions of tonnes of carbon. I don’t think anybody on Earth can visualise what numbers like these really look like. Yet, our future depends on us lowering the quantity of greenhouse gases in the atmosphere to safe levels before, so-called self-amplifying feedbacks take over - if they haven’t already. 

There is a clue emerging as to how we might accomplish such a feat - in the image of the Blue Marble NASA image of Earth. Namely that over 70 percent of the planet is ocean and the fate of life on Earth is intrinsically tied to that of the oceans. 

Currently - and it is no secret - the oceans are in a terminal decline, acidifying, heating, losing their biomass and, the worse bit, flipping from carbon sink to carbon source. Fish stocks are also depleted, as ocean ecosystems fall under the sad blanket of degradation. But what if, by a process of biomimicry, we could reverse these processes and restore the life in the oceans?

Guest post: Why BECCS might not produce ‘negative’ emissions after all. Dr. Anna Harper, Carbon Brief. Aug. 14, 2018.

Model scenarios that limit warming to 1.5C or 2C typically rely on large amounts of “negative emissions” to extract CO2 from the atmosphere and store it on land, underground or in the oceans. 

Bioenergy crops with carbon capture and storage (BECCS) is, perhaps, the most prominent of the various negative emissions techniques. There are many attractive features, since this technology would provide energy – thus reducing our need for fossil fuels – and remove CO2 from the atmosphere at the same time. 

However, the full carbon-cycle impacts of large-scale deployment of BECCS are not well studied. And, before now, no studies have looked at these impacts specifically for a scenario that could meet the 1.5C target. 

In our new study, published in Nature Communications, my colleagues and I find that expansion of bioenergy in order to meet the 1.5C limit could cause net losses in carbon from the land surface. Instead, we find that protecting and expanding forests could be more effective options for meeting the Paris Agreement.

Guest post: Six key policy challenges to achieving ‘negative emissions’ with BECCS. Dr. Clara Gough, Dr. Sarah Mander, Dr. Naomi Vaughan of Tyndall Centre for Climate Change Research, via Carbon Brief. Aug. 28, 2018.

scientific journal article here:

Challenges to the use of BECCS as a keystone technology in pursuit of 1.5⁰C. Dr. Gough et al, Journal of Global Sustainability. 2018.

Non-technical summaryBiomass energy with carbon capture and storage (BECCS) is represented in many integrated assessment models as a keystone technology in delivering the Paris Agreement on climate change. This paper explores six key challenges in relation to large scale BECCS deployment and considers ways to address these challenges. Research needs to consider how BECCS fits in the context of other mitigation approaches, how it can be accommodated within existing policy drivers and goals, identify where it fits within the wider socioeconomic landscape, and ensure that genuine net negative emissions can be delivered on a global scale.

Bioenergy carbon capture: climate snake oil or the 1.5-degree panacea? Paul Behrens, RenewEconomy. Oct. 23, 2018.

Carbon Capture’s Global Investment Would Have Been Better Spent On Wind & Solar. Michael Barnard, CleanTechnica. Apr. 21, 2019.

CCS is a rounding error in global warming mitigation. It’s hard to see how it could possibly be more. And it brings into stark relief the unfortunate reality that the IPCC depends far too much on carbon capture and sequestration approaches in terms of dealing with global warming.

Air Carbon Capture’s Scale Problem: 1.1 Astrodomes For A Ton Of CO2. Michael Barnard, CleanTechnica. Mar. 14, 2019.

Chevron’s Fig Leaf Part 1: Carbon Engineering Burns Natural Gas To Capture Carbon From The Air. Michael Barnard, CleanTechnica. Mar. 14, 2019.

The total CO2 load for the energy required for capture, processing, compression, storage, distribution and sequestration is almost certain to be greater than the CO2 removed from the atmosphere. 

This isn’t a one-article drive-by, but a five-piece assessment. 

• The first piece summarizes the technology and the challenges, and does a bottoms-up assessment to give context for what Carbon Engineering is actually doing. 
• The second piece steps through Carbon Engineering’s actual solution in detail. 
• The third piece returns to the insurmountable problem of scale and deals with the sheer volume of air that must be moved and the scale of machinery they have designed for the purpose. 
• The fourth article looks at the market for air carbon capture CO2 and assesses why three fossil fuel majors might be interested. 
• The final article addresses the key person behind this technology and the expert opinions of third parties such as Dr. Mark Jacobson of Stanford.

No path to climate stability without carbon dioxide removal. Walter Reid, Thomson Reuters. Aug. 24, 2018.

As hard as it is to reduce greenhouse gas emissions, an even bigger challenge lies ahead: We now need to remove much of what we’ve already added to the atmosphere. 

The math of climate change is simple and stark. To keep warming below 1.5 degrees Celsius, we can only emit another 600 Gigatons of carbon dioxide into the atmosphere. [ed: and this assumes that our carbon budget has been accurately calculated, which has been based on risk assessments that assume a 50% probability of not meeting our goals, and have been predicated on climate models that leave out factors that are not well-understood, including many amplifying/positive feedback effects; and, as we know, climate scientists have consistently and persistently been surprised by climate impacts and effects being observed much sooner than they had predicted.]

At current rates, this will take 14 years. [ed: as noted above, our true carbon budget, if it had been calculated accurately, including the impact of amplifying feedbacks, and excluding the assumption of future CDR, and allowing for only a tiny possibility (say 1%) of failure, has already likely been exhausted.] As a result, almost all scientific analyses assume large amounts of carbon dioxide begin to be removed from the atmosphere in the next decade, and by the second half of the century we must remove much more than we emit.

How much carbon dioxide are we talking about? Think of all the greenhouse gas emissions that will be emitted from all the cars, power plants, factories, and deforestation over the next 20 years. By 2100, we will need to take about that same amount out of the atmosphere. 

Here is the rub: We don’t know how to do carbon dioxide removal at that scale.

The one proven low-cost technology that we can turn to is the tree. Reforestation is, hands down, the best and most cost-effective approach to carbon dioxide removal. In addition to benefiting the climate, it also slows soil erosion, and often can increase water supplies, restore biodiversity, and provide economic benefits. But we have many competing uses for land – especially as the world population continues its growth towards eight billion people and incomes rise. Even the most promising reforestation scenarios don’t meet the full need for carbon removal. 

There are other promising but costlier approaches in early stages of development. “Direct Air Capture” relies on large fans blowing air through huge devices to capture carbon dioxide. Other strategies include weatherization of rocks and changing agricultural practices to store carbon in soils, which can also improve agricultural productivity. 

For carbon dioxide removal to grow at the pace needed, serious action must be taken now to create demand and to drive down the cost of new technologies. 

Luckily, some progress is already being made. Efforts to promote reforestation, for example, began in 2011 with the “Bonn Challenge,” which led to commitments from 47 national and subnational governments to restore nearly 400 million acres of land. Earlier this summer Sweden declared that it will be carbon neutral (with any emissions offset by carbon dioxide removal) by 2045 and carbon negative after that. 

But much more is needed. Meeting the goals of the Paris Climate Agreement will require gigaton-scale carbon dioxide removal. 

Just as actions to reduce carbon dioxide emissions were first catalyzed when governments and companies announced commitments to reduce emissions to the atmosphere, it is now time for leaders to announce specific, time-bound commitments to remove carbon dioxide from the atmosphere. These goals could be ratcheted up as technologies develop and costs drop. Investments in reforestation or enhanced soil carbon storage could be used to deliver on the commitments, as could procurement policies that create incentives to use carbon dioxide derived from direct air capture. Governments could also mandate that companies emitting greenhouse gases purchase “credits” that would pay for carbon dioxide removal with a technology like direct air capture. 

Since most of these strategies need further development quickly, there is also a vital role for mission investors and philanthropists to promote appropriate policies and identify ways to bring new technology to scale. 

While challenge is daunting, the opportunities are just as real. Markets already exist for carbon dioxide removal in the case of reforestation, and the market for carbon dioxide removal will grow dramatically in the coming decades. 

Next month, leaders from around the world will gather for the Global Climate Action Summit in San Francisco. The opportunity is ripe for governments and businesses to seize the leadership mantle by being among the first to commit to removing carbon dioxide from the atmosphere. Reducing emissions alone will not secure a stable climate and avoid the worst impacts of climate change. Now is the time to recognize that carbon dioxide removal is a central strategy in the fight against climate change.

Roadmap for Rapid Decarbonization. Rockstrom et al

A roadmap for rapid decarbonization. Johan Rockström, Hans Joachim Schellnhuber et al. Science. Mar. 24, 2017. PDF available here.

Summary

Although the Paris Agreement's goals (1) are aligned with science (2) and can, in principle, be technically and economically achieved (3), alarming inconsistencies remain between science-based targets and national commitments. Despite progress during the 2016 Marrakech climate negotiations, long-term goals can be trumped by political short-termism. Following the Agreement, which became international law earlier than expected, several countries published mid-century decarbonization strategies, with more due soon. Model-based decarbonization assessments (4) and scenarios often struggle to capture transformative change and the dynamics associated with it: disruption, innovation, and nonlinear change in human behavior. For example, in just 2 years, China's coal use swung from 3.7% growth in 2013 to a decline of 3.7% in 2015 (5). To harness these dynamics and to calibrate for short-term realpolitik, we propose framing the decarbonization challenge in terms of a global decadal roadmap based on a simple heuristic—a “carbon law”—of halving gross anthropogenic carbon-dioxide (CO2) emissions every decade. Complemented by immediately instigated, scalable carbon removal and efforts to ramp down land-use CO2emissions, this can lead to net-zero emissions around mid-century, a path necessary to limit warming to well below 2°C.

The Paris goal translates into a finite planetary carbon budget: a 50% chance [ed: don't we want a 95 or 99% chance? what's our budget for that?] of limiting warming to 1.5°C by 2100 and a >66% probability of meeting the 2°C target imply that global CO2 emissions peak no later than 2020, and gross emissions decline from ∼40 gigatons (metric) of carbon dioxide (GtCO2)/year in 2020, to ∼24 by 2030, ∼14 by 2040, and ∼5 by 2050 (3) (see the figure, top). Risks could be further reduced by moderately increasing ambition to halve emissions every decade (see the figure, bottom right). Following such a global carbon law means at least limiting cumulative total CO2 emissions from 2017 until the end of the century to ∼700 GtCO2, which allows for a small but essential contingency (∼125 GtCO2 less compared with total CO2 emissions in the pathway in the figure, top) for risks of biosphere carbon feedbacks (6) or delay in ramping up CO2-removal technologies.

A carbon law applies to all sectors and countries at all scales and encourages bold action in the short term. It means, for example, doubling of zero-carbon shares in the energy system every 5 to 7 years, a rate consistent with the trajectory of the past decade (see the figure, bottom left). All sectors (e.g., agriculture, construction, finance, manufacturing, transport) need comparable transformation pathways. In addition, in the absence of viable alternatives, the world must aim at rapidly scaling up CO2 removal by technical means from zero to at least 0.5 GtCO2/year by 2030, 2.5 by 2040, and 5 by 2050. CO2 emissions from land-use must decrease along a nonlinear trajectory from 4 GtCO2/year in 2010, to 2 by 2030, 1 by 2040, and 0 by 2050 (see the figure, bottom right). The endgame is for cumulative CO2 emissions since 2017 to be brought back from around 700 GtCO2 to below 200 GtCO2 by the end of the century (see the figure, top) and atmospheric CO2 concentrations to return to 380 ppm by 2100 (currently at 400 ppm). [ed: we should be aiming for 280, as per Schellnhuber, i.e. the level before we started anthropogenic global warming... or at least 350]

Roadmaps are planning instruments, linking shorter-term targets to longer-term goals. They help align actors and organizations to instigate technological and institutional breakthroughs to meet a collective challenge. An explicit carbon roadmap for halving anthropogenic emissions every decade, co-designed by and for all industry sectors, could help promote disruptive, nonlinear technological advances toward a zero-emissions world. The key to such a carbon law will be a dual strategy that pushes renewables and other zero-emissions technologies up the creation and dissemination trajectory, while simultaneously pulling fossil-based value propositions from the market. Thus, the transformation unfolds at a pace governed by novel schemes rather than by inertia imposed by incumbent technologies (see the figure, bottom left).

We sketch out a broad decadal decarbonization narrative in four dimensions—innovation, institutions, infrastructures, and investment—to provide evidence of feasibility and depth of transformation for economies to stay on a carbon-law trajectory. The narrative provides no guarantees but identifies crucial steps, grounded in published scenarios combined with expert judgment. Each step has two parts: actions for rapid near-term emissions reductions, and actions for systemic and long-term impact, creating the basis for the next steps. Such a narrative, specifically designed with decadal targets and incentives, could provide key elements for national and international climate strategies.


2017–2020: No-Brainers

Annual emissions from fossil fuels must start falling by 2020. Well-proven (and ideally income-neutral) policy instruments such as carbon tax schemes, cap-and-trade systems, feed-in tariffs, and quota approaches should roll out at wide scale. Even these will be challenging in the emerging global political climate. The European Union emissions-trading scheme requires kick-starting through an appropriate floor price (>$50/metric ton CO2).

A global carbon law and roadmap to make Paris goals a reality

(Top) A deep decarbonization scenario scientifically consistent with the Paris Agreement (3) and its associated carbon fluxes as computed with a simple carbon cycle and climate model (13). The “carbon law” scenario of halving emissions every decade is marginally more ambitious than the scenario presented. Meeting the Paris Agreement goals will require bending the global curve of CO2 emissions by 2020 and reaching net-zero emissions by 2050. It furthermore depends on rising anthropogenic carbon sinks, from bioenergy carbon capture and storage (BECCS) engineering (yellow) and land use (orange), as well as sustained natural sinks, to stabilize global temperatures. This scenario is broadly consistent with a 75% probability of limiting warming to below 2°C; a median temperature increase of 1.5°C by 2100; estimated peak median temperature increase of 1.7°C; a 50% probability of limiting warming to below 1.5°C by 2100; and CO2 concentrations of 380 ppm in 2100. See supplementary materials (SM). (Bottom left) Nonlinear renewable energy expansion trajectories based on 2005–2015 global trends (13). Keeping the historical doubling times of around 5.5 years constant in the next three decades would yield full decarbonization (blue area) in the entire energy sector by ∼2040, with coal use ending around 2030–2035 and oil use, 2040–2045. Calculations, based on (5), are detailed in SM. (Bottom right) Decadal staircase following a global carbon law of halving emissions every decade, a complementary fall in land-use emissions, plus ramping up CO2 removal technologies.

GRAPHIC: N. CARY/SCIENCE

The United Nations Framework Convention on Climate Change (UNFCCC) should transform into a vanguard forum where nations, businesses, nongovernmental organizations, and scientific communities meet to refine the roadmap. It is evident that the current national commitments under the Paris Agreement must be strongly enhanced at the first ratcheting-up cycle in 2018 to 2020.

Fossil-fuel subsidies, currently $500 billion to $600 billion per annum, must be eliminated by 2020, not 2025 as agreed by the Group of Seven (G7) nations in 2016. An immediate moratorium on investment in new unabated coal-based energy would minimize future stranded assets. China's greenhouse gas (GHG) output must continue to decrease over the coming years, through aggressive funding of renewables, by abandoning coal expansion, and by closing mines. The richer coal-intensive countries must spearhead the coal exit, and countries like India and Indonesia must follow suit.

By 2020, all cities and major corporations in the industrialized world should have decarbonization strategies in place. The 49 countries already committed to be carbon neutral by 2050 should have expanded to >100 countries by that time, and implementation should be under way. The gravest risk is that emerging economies, such as South Africa, are driven down the conventional growth path by sheer inertia. International efforts must incentivize low-carbon development as a priority.

Food production contributes to >10% of global GHG emissions (4) and weakens natural carbon sinks yet has vast potential for biological carbon removal. Innovative financial mechanisms are needed to incentivize carbon management in the food system. Agro-industries, farms, and civil society should develop a worldwide strategy for sustainable food systems to drive healthier, low-meat diets (7) and reduce food waste (8). Health and sustainability co-benefits—such as obesity and disease abatement, pollution reduction, and ecosystems preservation—should spur action.


2020–2030: Herculean Efforts

Economies must implement the no-brainer mitigation measures plus the first wave of smart and disruptive action. Improving energy efficiency alone would reduce emissions 40 to 50% by around 2030 in many domestic and industrial cases (9).

In the 2020s, carbon pricing across the world must expand to cover all GHG emissions, starting at $50 per metric ton at least and exceeding $400 per ton by mid-century. By the end of that decade, coal will be about to exit the global energy mix, cities like Copenhagen and Hamburg will be fossil-fuel free, and cap-and-trade regimes should be firmly established across national and regional economic zones along with adequate carbon taxes on air transport and shipping. Countries should follow Norway, Germany, and the Netherlands and announce the phase-out of internal combustion engines in new cars by 2030 at the latest. Decarbonizing long-distance transport will be key, through renewable fuels, electrification, and replacing shorter-haul air traffic by rapid rail. These commitments will signal that the conventional model of reinvesting fossil-fuel revenues into exploration is obsolete.

Public and private investment in research and development (R&D) for climate solutions should increase by an order of magnitude between now and 2030. Substantial resources must be directed toward more efficient modes of industrial production; battery-life extension and improved energy storage solutions; schemes that greatly reduce the cost of carbon capture and storage (CCS) within 10 years; alternative aircraft propulsion systems; super-smart power grids; and sustainable urbanization everywhere.

We need urgent research to ascertain the resilience of remaining biosphere carbon sinks (10). Strong financial impetus must be provided for afforestation of degraded land and for establishment of no-regret approaches to net removal of CO2 from the atmosphere—such as the combination of second- and third-generation bioenergy with CCS (BECCS) or direct air CCS (DACCS). Trials of sustainable sequestration schemes of the order of 100 to 500 MtCO2/year should be well under way to resolve deployment issues relating to food security, biodiversity preservation, indigenous rights, and societal acceptance.


2030–2040: Many Breakthroughs

By 2040, oil will be about to exit the global energy mix. Several vanguard countries (such as Norway, Denmark, and Sweden) should have completed electrification of all sectors and be entirely emissions-free or close to it. Internal combustion engines for personal transport will have become rare on roads worldwide. Aircraft fuel should be entirely carbon neutral. Synthesized fuels, bio-methane, and hydrogen are established alternatives.

After 2030, all building construction must be carbon-neutral or carbon-negative. The construction industry must either use emissions-free concrete and steel or replace those materials with zero- or negative-emissions substances such as wood, stone, and carbon fiber.

BECCS schemes totalling 1 to 2 GtCO2/year would roll out, and R&D should focus on doubling the annual rate of CO2 removal. We can expect that polycentric power grids using supraconductive cables will start supplying energy in developing countries, and radical new energy generation solutions will enter the market.

Promising financial mechanisms to foster investments in necessary breakthroughs include sovereign wealth funds designed for transformation; effective international corporation tax regimes (11); and inheritance reforms that account for historical wealth generated by fossil fuels without compensation of externalities (12).


2040–2050: Revise, Reinforce

Building on successes and learning from failures of previous stages, certain mitigation strategies will be abandoned and others refined and amplified. All major European countries become close to net-zero carbon states early in the 2040s; market dynamics push North and South America and most of Asia and Africa to this goal by the end of the decade. Natural gas still provides some backup energy, but CCS ensures its carbon footprint is limited. Modular nuclear reactors may contribute to the energy mix in places.

By 2050, the world will have reached net-zero CO2 emissions, with a global economy powered by carbon-free energy and fed from carbon-sequestering sustainable agriculture. Meanwhile, BECCS schemes have been scaled up and draw down >5 GtCO2/year. Alternatively, concerns may rule out such scale-up. Only deep emission reductions during 2020–2030 can enable BECCS to be scaled back or abandoned, while efforts to increase energy efficiency and DACCS continue.


Stability and Resilience

We cannot predict where civilization will be mid-century, but a decadal staircase based on a carbon law, if adopted broadly, may provide essential economic boundary conditions to make a zero-emissions future an inevitability rather than wishful thinking. The very nature of disruptive progress requires revising the narrative of a detailed roadmap every 2 years, correcting near-term targets to reach the ultimate goal by evolutionary management.

Although signs are positive that the world is on track to rapidly transform to a net-zero–emissions global economy, contagion dynamics cut both ways. If political signals do not support a rapid transition, for example, by a failure to implement worldwide financial and regulatory reform that places a cost on carbon, then it is difficult to imagine keeping warming at “well below 2°C.” However, the scale of momentum toward clean energy in the past decade suggests that it would seem foolish to try to halt the trend, given the growing evidence that decarbonization can be a major pro-growth strategy.

In global governance, climate stabilization must be placed on par with economic development, human rights, democracy, and peace. The design and implementation of the carbon roadmap should therefore take center stage at the UN Security Council, as these quintessential objectives increasingly interact, influencing the stability and resilience of societies and the Earth system.