Welcome to the "Carbon Removal Dialogue," a new feature on the Center For Carbon Removal blog where we ask experts to share their thoughts on important questions related to carbon removal. We'll consolidate the responses into a single post, and we hope that the dialogue continues in the comment section, below.
Thanks to all of the experts that have responded, and without further ado, our first Carbon Removal Dialogue...
Can fossil energy with carbon capture and storage (CCS) be a bridge to net-negative CCS systems, including bioenergy with CCS and direct air capture and sequestration? If so, how; and if not, why not?
Brent R. Constantz, Ph.D.
Chief Executive Officer
CCS depends on purifying CO2 from fossil flue gas from coal and natural gas fired power plants and cement plants. The step of extracting and purifying the CO2 from a dilute state (12 - 15% for coal, 3 - 5% for natural gas, and 20 - 30% for cement) is the most significant problem with CCS because of the very large energy demand to purify it to near 100% for compression and liquification, transport, storage and monitoring. No process that requires a high energy demand purification step using conventional methods will ever, even at the theoretical best, lead to any sustainable carbon removal solution due to the energy required for the purification step. I don’t see a need for purification in net-negative systems, and if they would include the purification step, they would have to have a new novel approach (such as Blue Planet) that is different from the purification step processes currently being developed and funded. In general, I don’t think continued efforts on the conventional carbon dioxide purification processes being pursued for compression and liquification will help bridge to net-negative CCS system (or CCUS).
Roger D. Aines
Fuel Cycle Innovations Program Leader
The 10 million tons of CO2 placed in underground storage by the US CCS demonstration programs demonstrates that we can put CO2 out of reach of the atmosphere, a critical requirement for any carbon dioxide removal method. These kind of technology innovations and demonstrations will pave the way for bio-CCS and atmospheric capture.
Scientist - Climate & Clean Air Program
Deputy Director - Science Center Program
Combating climate change requires us to reduce carbon pollution significantly, and to do so fast. In an effort to quantify how much more carbon the atmosphere can tolerate while giving us a decent chance of avoiding dangerous climate change, researchers talk about “carbon budgets.” Between now and 2050, the budget is around the 500 billion metric tons of CO2 mark, and a little under double that by the end of the century. The problem is how we use fossil fuels today. Collectively, the world’s proven fossil fuel reserves as we know them today would generate close to 3,000 billion metric tons of CO2 – many times over the safe limit. Clearly, we cannot use these fossil fuels reserves without frying the planet. Moreover, almost 35% of the world’s installed capacity of coal-fired power plants – the worst cumulative carbon perpetrators – is ten years old or less. These plants are commonly worth upward of a billion dollars, and have a projected lifetime of several decades. Alone, they will take up the lion’s share of the allowed carbon budget. We need a means of substantially reducing their carbon emissions.
That’s where Carbon Capture & Sequestration (CCS) comes in. This is a technology that is ready to be used today at scale, but needs a cheaper price tag to become more widespread – something that targeted deployment programs will take care of if governments pursue them seriously. Will it actually be used, and will it be enough? A prudent approach does not assume that the answer is “yes”. Finding ways to remove carbon directly from the atmosphere, whether they are based on biomass or direct engineering, could enhance our capabilities and options if we delay emission cuts, or blow our carbon budget. Open questions remain today, however, on the economics, scalability and life cycle carbon footprint for many processes that remove carbon directly from the atmosphere. Achieving progress in this area would be very beneficial. It is not clear whether conventional CCS is a pathway to commercializing atmospheric removal technologies. To the extent that the latter rely on geologic sequestration to achieve an overall negative carbon footprint, then CCS can fast track the development of injection sites and experience in operating these. Beyond that, at this point the approaches strike me as sufficiently distinct that the fate of one is not tied to the fate of the other. However, both are worth pursuing independently: CCS as a climate mitigation measure that could begin reducing emissions meaningfully today, and atmospheric removal approaches as processes that need to be further developed, tested and refined so that they establish themselves as affordable, scalable and effective approaches to achieving net-negative emissions.
Daniel L. Sanchez
Ph.D. Candidate, Energy and Resources Group
Absolutely. Fossil CCS is not just a bridge to BECCS and other carbon-negative energy systems, but an essential part of their path to commercialization. Not only do advanced fossil and advanced biomass conversion systems share common characteristics, but co-conversion of coal, natural gas, and biomass enables producers to meet a variety of cost, performance, and carbon-intensity goals. This optionality is key to any path to market for BECCS.
There are some notable exceptions, however: biomass resources are more distributed than fossil resources, and transportation can be costly and complex. Biomass combustion and gasification is also more complicated than similar processes for coal and natural gas.
More broadly, carbon dioxide removal shares many characteristics with other carbon management techniques: this applies to both chemical and biological strategies to remove CO2 from the atmosphere. This means that any future "carbon removal" industry and "carbon management" industry can work together to both reduce emissions of CO2 to the atmosphere, AND concentrations of CO2 in the atmosphere.
I agree we are going to need net negative emissions because CO2 levels are already too high (and they will go higher). When it comes to fossil CCS, the need is obvious. Since CO2 lasts in the atmosphere for a very long time (100’s to 1000’s of years) it is the total cumulative amount of emissions that matter. A ton of CO2 that is captured and sequestered from a coal or natural gas power plant is one ton less that needs to be captured from the air or some other “net negative” scheme. And since capture from power plants and other “point sources” is far less expensive than air capture, it makes sense to focus CCS on power plants (fossil or bio) right now. Yes, we should shut down coal plants and phase out natural gas power plants as soon as possible, but I don’t see that happening until way beyond the “too late” stage.
We need to commercialize CCS technology right away and that means fossil plants for now. Air capture is still in the R&D stage and needs more work before it becomes practical and affordable. Also note that CCS technology is not the issue. Incentives (and regulations) are. Right now, power plant operators can pollute for free. Until we change that, no technology that costs more than $0/ton will have widespread deployment. The best way to implement the proper incentives is with a Fee and Dividend policy. See my TEDx talk on that https://www.youtube.com/watch?v=0k2-SzlDGko.
As for bio-power plus CCS, it’s good scheme but I understand that the amount of bio material available for power production is limited compared to our power needs and the amount of CO2 we need to remove from the atmosphere. We therefore need to also focus on wind and solar (and nuclear) for power generation and “mechanical” CCS and air capture.
As for paving the way, fossil CCS will give us experience with carbon sequestration and utilization (turning CO2 into something useful). Also, point source CCS can be the “second stage” of an air capture system (and can be directly used in a bio-energy power plant).
Acting General Manager- Americas
CCS for not only fossil but also for other industries that have no other choice but CCS in removing carbon emissions is indeed a GATEWAY technology to net negative CCS systems such as BECCS. Bio energy as a renewable energy form can provide near neutral emissions, but when combined with CCS, the result is net negative emissions.
One of the key technical challenges for CCS is reducing its cost (primarily in capture) which requires research, development, demonstration and deployment so we can learn by doing. A key challenges for bio energy is in reducing the energy and costs of gathering bio feedstocks to produce bio energy. These dual challenges are important to the large scale deployment of BECCS. With CCS projects operating or under construction and many more at various stages, a solid foundation for CCS is being established that will allow it to be broaden to such applications as BECCS. For example, in the UK, there is the White Rose capture project that will burn wood chips and capture the carbon emissions for storage under the North Sea is a BECCS project. I refer you to the article in the New Scientist at https://www.newscientist.com/article/mg22730334-800-uk-to-build-worlds-first-power-plant-with-negative-emissions/.
In addition the Climate Institute produced a BECCS report which the Global CCS Institute commissioned a year ago and is worth a read. With respect to direct air capture, which is in a nascent development stage and thus currently a longer range option, reducing the cost of CCS through transformational technologies is even more important to that application. The current focus of research on transformational technologies for reducing capture costs in CCS is a high priority for the US Department of Energy given its recent announcement of 16 research projects on transformational capture technologies for fossil based systems.
Vice President, Summit Carbon Capture
Fossil CCS offers a platform that will, over time, lead to numerous other forms of CCS across various technologies with ever increasing CO2 benefits. This holds true even with marginal technology overlap between existing forms of CCS that can be applied to power plants today and the sorts of carbon negative systems being envisioned in the future. This is because the regulatory frameworks, policy designs, supporting technologies, and intellectual capacity that are formed around fossil CCS will expand to include and eventually drive deeper reductions through other techniques to capture and store CO2. For example, it will take time to establish rigorous and workable CO2 storage regulatory regimes that include protocols for certifying long-term storage, methodologies for generating environmental credits, and commercial approaches for managing long-term storage liabilities. If these matters can be sorted out around fossil CCS projects now, then they can be leveraged to support more innovative carbon dioxide removal schemes later. The lack of such practical frameworks will serve as a barrier to innovation and commercial progress in the field of carbon removal.
Not only do I think fossil energy with CCS can serve as bridge to bioenergy with CCS, but I think that it must serve as a bridge for either technology to gain widespread adoption. Here's why:
Bioenergy with CCS (bio-CCS) needs fossil energy with CCS. The more fossil energy with CCS projects that get built, the lower costs (such as technology, regulatory, project finance, etc.) become for many CCS projects. Because fossil energy with CCS is less expensive than bio-CCS, it is more likely to find economically viable market opportunities in the near-term. Without fossil CCS projects driving down bio-CCS costs, I worry that we will always see bio-CCS as too expensive an option, and we won't pursue the R&D investments needed to bring down costs to acceptable levels.
But fossil energy with CCS also needs bio-CCS. Many renewable energy advocates see fossil CCS as enabling “business as usual” for polluting energy companies, and thus do not throw their support behind programs to support early deployments of fossil CCS projects. “Renewable CCS” in the form of bio-CCS, however, is something that renewable energy advocates are naturally more inclined to support. If fossil energy with CCS projects can credibly commit to serving as a bridge to bio-CCS in the future (through agreements to ratchet up biomass co-firing, or by supporting RPS-like standards for bio-CCS in the future, for example), they are more likely to get the support they need to get early projects built and deployed.
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