The power industry has always evolved to meet the rising energy demands of communities across the U.S. That demand is now shifting from energy powered by fossil fuels to greener alternatives that can help the world reach its goal of keeping global warming under 1.5C.
The latest report from IPCC, the Intergovernmental Panel on Climate Change, notes that reaching that target is no longer possible by reducing emissions alone. Turning to newer methods of carbon reduction, such as Direct Air Capture (DAC), can help reduce the concentration of carbon dioxide in the atmosphere and address the need to mitigate climate change. These technologies are taking center stage in climate tech conversations, but according to Dr. Luke Shors, there continue to be misconceptions about DAC and as a potential tool to achieve Paris Agreement temperature targets.
Shors, a researcher and writer who focuses on global health and climate, provided POWER with his insight about DAC and how the technology can help reduce carbon emissions. Shors, a co-founder of the carbon removal initiative Capture6, holds a doctorate from the Harvard Graduate School of Education where he also was a fellow at the Harvard Center on Energy and the Environment.
POWER: How do we know DAC can work? Is the technology proven?
Shors: DAC is a set of engineering techniques that mimic what trees and plants do in nature—remove carbon dioxide from the atmosphere. It is a “negative emissions technology” (NET) as the overall process achieves carbon dioxide removal, distinct from carbon offsets that are systems by which emissions from activities in one location are “offset” by activities elsewhere that promise to result in carbon removal or reduced emissions.
DAC technology is not a mere concept or experiment; it has advanced significantly in recent years. Some DAC approaches have been rigorously tested, and its principles are well understood. The industry is still nascent, but several DAC companies have begun announcing and deploying new facilities and pilots to showcase their ability to remove atmospheric CO₂ using different processes and technologies: Project Bison, Project Monarch, Carbon Project in Texas, and Orca Project among others.
POWER: Won’t DAC take away valuable resources from the renewable energy grid?
Shors: Carefully planned CDR (carbon dioxide removal) projects can serve as catalysts for developing renewable energy. Integrating CDR technologies like DAC with renewable energy can provide a long-term offtake for new renewable energy facilities. New DAC facilities can help lower consumer energy prices and improve energy access. This can include boosting the development of renewable energy in areas that may have not previously had access to green, or cleaner, electricity. In addition, some DAC facilities can generate net negative co-products, such as green chemicals and freshwater, and therefore make their use of energy more efficient.
The challenge for DAC companies to show that their facilities can be built efficiently and at scale without taking away renewable energy from the grid is a complex one. It’s an exciting challenge, given the existing financial incentives are giving DAC companies a shot to prove their facilities are not built at a cost to cutting emissions.
POWER: Shouldn’t the industry focus on emission reductions instead?
Shors: Addressing climate change requires simultaneous and dramatic progress on various levels:
- Limiting new emissions (reduction).
- Drawing down the existing stock of greenhouse gases that have been accumulating since the industrial revolution (removal).
- Making society more resilient to climate effects (adaptation).
Focusing on all the strategies is the best way to fight against the effects of climate change. It may seem conceptually simpler to work on one thing at a time—to get our emissions in order before shifting to carbon removal. Yet with the window to reach 1.5C or even 2C closing, we simply don’t have the time for such a sequential strategy.
Radically reducing the emissions of climate gases is essential, but not all emissions can be easily removed. Complementing reduction efforts with technologies that remove residual and historical emissions from the atmosphere to reach net-zero is needed.
The science community estimates that even if the world hits all its emissions reduction targets by 2050, it still needs to remove 5 to 16 Gt of CO₂ yearly to prevent catastrophic environmental impacts. Carbon removal is the solution to close this gap.
POWER: Is DAC too expensive to achieve the scale needed?
Shors: The cost of not acting on every solution available is higher than the cost of investing in DAC.
DAC technology is currently more expensive (between $250 to $600/tonne) than other climate mitigation and nature-based carbon capture technologies. However, with continuing supportive policies and market developments, there is a strong potential to accelerate the deployment rate and drive the price down to below $100/tonne.
POWER: Some people may look at the costs and ask, ‘Why don’t we plant trees instead?’
Shors: There are many different ways to remove carbon, from planting new forests to shifting agricultural practices for soil-based sequestration, and all help to achieve carbon removal on a gigaton scale.
What’s needed is a broad portfolio of solutions that can be optimized for different conditions worldwide. Each has its benefits in the fight to stem climate change when done right. But most are not permanent or without complications. For example, trees take time to grow and are vulnerable to fires that release the carbon they store. Resolving the issues can’t rely solely on nature-based solutions due to geospatial limitations. There isn’t enough land to plant enough trees to remove enough CO₂ to curb climate change without displacing vast numbers of people or other land uses.
POWER: Doesn’t DAC enable utilities to keep generating non-renewable power?
Shors: Carbon removal buyers cannot use carbon removal credits as a justification to continue using non-renewable power and operate within the “business as usual” climate scenario.
Carbon removal should be seen as a complementary approach to reducing emissions rather than a substitute. The primary focus still needs to be on reducing emissions in the first place and power generators play a pivotal role in this process. Still, by disaggregating emissions targets from removals targets, we can avoid the moral hazard of allowing CDR technologies to stall emissions reductions.
DAC does not depend on fossil fuels to operate, as it can be powered by renewable energy sources like solar and wind.
POWER: Can DAC make enough of an impact in time?
Shors: The world needs to prioritize immediate and aggressive emissions reduction strategies while investing in and developing carbon removal for long-term greenhouse gas removal.
Scaling up DAC to make a significant impact will require substantial investments, technological advancements, and infrastructure development. The speed at which DAC can be deployed on a large scale will influence its overall effect on climate change. As seen in case of solar energy, what started as a marginal technology has now become one of the most significant emission reduction tools.
A comprehensive approach that combines emissions reduction efforts, renewable energy deployment, energy efficiency improvements, and other sustainable practices is crucial to keeping global warming in check.
—Darrell Proctor is a senior associate editor for POWER (@POWERmagazine).