The goal of carbon capture and storage (CCS), also called carbon sequestration, is to take carbon dioxide that would have been emitted into the atmosphere from new or existing power plants (usually coal) and instead store it someplace, hopefully forever. It is an attractive idea across the political spectrum because it might allow us to continue using a major fossil fuel, but in a way that does not destroy the climate.
Unfortunately, CCS has four fundamental problems that have reduced enthusiasm for it recently and limited its likely role:
- Cost: Coal plants with CCS are very expensive today. The total extra cost for this process, including geological storage in sealed underground sites, is currently quite high, $30 to $80 a ton of carbon dioxide, according to the Department of Energy’s Office of Fossil Energy, “Carbon Sequestration R&D Overview.” And that is on top of the cost of new coal plants, which have become very expensive. In the future, it seems rather unlikely that CCS would be a low-cost solution. The modeling work done for the California Public Utility Commission on how to comply with the AB 32 law (California’s Global Warming Solutions Act), online here, puts the cost of coal gasification with carbon capture and storage at a staggering 16.9 cents per kWh. Energy efficiency along with lots of low-carbon generation sources beat that easily now or will very soon.
- Timing: The world does not even have a single large-scale (300+ MW) coal plant with CCS anywhere in the world. The first moderate-sized (30 MW) pilot plant with CCS just started up this month in Germany. Earlier this year, President Bush dropped the mismanaged ‘NeverGen’ clean coal project. In the past year, most governments and most U.S. utilities have scaled back, delayed, or cancel their planned CCS projects (see below). As Howard Herzog of MIT’s Laboratory for Energy and the Environment said in February, “How can we expect to build hundreds of these plants when we’re having so much trouble building the first one?“
- Scale: We need to put in place a dozen or so clean energy “stabilization wedges” by mid-century to avoid catastrophic climate outcomes. For CCS to be even one of those would require a flow of CO2 into the ground equal to the current flow of oil out of the ground. That would require, by itself, re-creating the equivalent of the planet’s entire oil delivery infrastructure, no mean feat.
- Permanence and transparency: If Putin’s Russia said it was sequestering 100 million tons of CO2 in the ground permanently, and wanted other countries to pay it billions of dollars to do so, would anyone trust them? No. The potential for fraud and bribery are simply too enormous. But would anyone trust China? Would anyone trust a U.S. utility, for that matter? We need to set up some sort of international regime for certifying, monitoring, verifying, and inspecting geologic repositories of carbon — like the U.N. weapons inspections systems. The problem is, this country hasn’t been able to certify a single storage facility for a high-level radioactive waste after two decades of trying and nobody knows how to monitor and verify underground CO2 storage. It could take a decade just to set up this system.
The bottom line is that we should continue to pursue CCS research, development, and demonstration in a serious effort to turn this long-term strategy into a medium-term one. But efficiency, wind, solar PV, and baseload solar are where we should be placing the big deployment dollars right now.
For those who want to become more knowledgeable on CCS, the rest of this post will cite and excerpt a dozen or so of the recent articles and studies on the subject below.
The Massachusetts Institute of Technology published a very thorough, interdisciplinary report on “The Future of Coal” in March 2007. This study was quite skeptical about the near-term possibility of CCS, mocked the notion of “capture ready” coal plants, and harshly criticized U.S. government CCS policy — a key reason that many, including journalists, became more pessimistic about CCS. Findings include:
- A significant charge on carbon emissions is needed in the relatively near term to increase the economic attractiveness of new technologies that avoid carbon emissions and specifically to lead to large-scale CCS in the coming decades. We need large-scale demonstration projects of the technical, economic and environmental performance of an integrated CCS system.
- Congress should remove any expectation that construction of new coal plants without CO2 capture will be “grandfathered” and granted emission allowances in the event of future regulation. This is a perverse incentive to build coal plants without CO2 capture today.
- Coal plants will not be cheap to retrofit for CO2 capture. Our analysis confirms that the cost to retrofit an air-driven SCPC plant for significant CO2 capture, say 90 percent, will be greater than the cost to retrofit an Integrated Gasification Combined Cycle plant. However, as stressed in Chapter 3, the modifications needed to retrofit an IGCC plant for appreciable CCS are extensive and not a matter of simply adding a single simple and inexpensive process step to an existing IGCC plant.
- The concept of a “capture ready” IGCC or pulverized coal plant is as yet unproven and unlikely to be fruitful.
In May 2007, the Center for American Progress released an excellent report on “Global Warming and the Future of Coal,” by Ken Berlin and Robert Sussman. It looked at a variety of policy measures that might allow new coal to contribute to our energy mix without destroying the climate and recommended the crucial policy:
Requiring all new coal power plants to meet an “emission performance” standard that limits CO2 emissions to levels achievable with CCS systems.
That is the best way to maintain coal’s viability in a carbon-constrained world.
The U.K. Guardian reported in February 2008, “Firms will act on CO2 only if its cost triples,” says oil giant Royal Dutch/Shell:
A carbon price close to $100 per tonne of CO2 — more than three times higher than it is today — is needed before industry will invest in the thousands of carbon-capture-and-storage (CCS) schemes needed for reducing greenhouse gas emissions, Shell warned yesterday.
In April, a major article in Environmental science and technology, “Regulating the Geological Sequestration [GS] of CO2,” argued
As greenhouse gas emissions rise and the impacts of climate change grow, the need for safe and effective CO2 capture and sequestration becomes ever more urgent …
For countries such as the U.S. and Germany, which today produce more than half of their electricity from coal, or China and India, where a large majority of the electricity is generated from coal, it is difficult to see how cost-effective and politically viable emission reductions can be achieved during the next several decades without at least some continued use of coal …
Governments worldwide should provide incentives for initial large-scale GS projects to help build the knowledge base for a mature, internationally harmonized GS regulatory framework. Health, safety, and environmental risks of these early projects can be managed through modifications of existing regulations in the EU, Australia, Canada, and the U.S. An institutional mechanism, such as the proposed Federal Carbon Sequestration Commission in the U.S., should gather data from these early projects and combine them with factors such as GS industrial organization and climate regime requirements to create an efficient and adaptive regulatory framework suited to large-scale deployment. Mechanisms to structure long-term liability and fund long-term postclosure care must be developed, most likely at the national level, to equitably balance the risks and benefits of this important climate change mitigation technology.
We need to do this right. During the initial field experiences, a single major accident, resulting from inadequate regulatory oversight, anywhere in the world, could seriously endanger the future viability of GS. That, in turn, could make it next to impossible to achieve the needed dramatic global reductions in CO2 emissions over the next several decades. We also need to do it quickly. Emissions are going up, the climate is changing, and impacts are growing. The need for safe and effective CO2 capture with deep GS is urgent.
In April, Reuters reported:
Governments and the private sector are balking at the expense of kick-starting a technology to bury planet-warming gases underground, casting doubts on “clean coal” plans seen vital to help fight climate change.
In May, Matt Wald wrote in the NYT, “Mounting Costs Slow the Push for Clean Coal,”
… It has become clear in recent months that the nation’s effort to develop the technique is lagging badly.
In January, the government canceled its support for what was supposed to be a showcase project, a plant at a carefully chosen site in Illinois where there was coal, access to the power grid, and soil underfoot that backers said could hold the carbon dioxide for eons.
Perhaps worse, in the last few months, utility projects in Florida, West Virginia, Ohio, Minnesota and Washington State that would have made it easier to capture carbon dioxide have all been canceled or thrown into regulatory limbo.
Coal is abundant and cheap, assuring that it will continue to be used. But the failure to start building, testing, tweaking and perfecting carbon capture and storage means that developing the technology may come too late to make coal compatible with limiting global warming.
“It’s a total mess,” said Daniel M. Kammen, director of the Renewable and Appropriate Energy Laboratory at the University of California, Berkeley.
… it remains an open question whether techniques for capturing and storing carbon dioxide will be available by the time they are critically needed.
The Electric Power Research Institute, a utility consortium, estimated that it would take as long as 15 years to go from starting a pilot plant to proving the technology will work. The institute has set a goal of having large-scale tests completed by 2020.
“A year ago, that was an aggressive target,” said Steven R. Specker, the president of the institute. “A year has gone by, and now it’s a very aggressive target.”
The Australian reported in May, “Chimneys sweep BP clean coal plan away”:
WHAT was touted as Australia’s biggest contribution to developing clean coal technology for use around the world in reducing greenhouse gas emissions has been scrapped even before it got to first base.
BP confirmed yesterday the $2 billion “hydrogen energy” coal-to-gas plant at Kwinana, south of Perth, would not proceed …
But after more than two years of investigations and several million dollars of research, BP has now admitted that the geological formations off Perth contain gas “chimneys” that mean it is next to impossible to establish a seal in the strata that could contain the CO2.
In May, Greenpeace issued a report, False Hope: Why carbon capture and storage won’t save the climate that argued “the technology is largely unproven and will not be ready in time to save the climate.”
And Matt Wald again in June, “Running in Circles Over Carbon”:
… A recent decision by the Virginia State Corporation Commission, which regulates utilities, to turn down an application by the Appalachian Power Company to build a plant that would have captured 90 percent of its carbon and deposited it nearly two miles underground, at a well that it dug in 2003. The applicant’s parent was American Electric Power, one of the nation’s largest coal users, and perhaps the most technically able. But the company is a regulated utility and spends money only when it can be reimbursed.
The Virginia commission said that it was “neither reasonable nor prudent” for the company to build the plant, and the risks for ratepayers were too great, because costs were uncertain, perhaps double that of a standard coal plant. And in a Catch-22 that plagues the whole effort, the commission said A.E.P. should not build a commercial-scale plant because no one had demonstrated the technology on a commercial scale.
A key comparison illustrates the daunting scale of the challenge. In 2005 worldwide CO2 emissions amounted to nearly 28 Gt; even if were to set out only a modest goal of sequestering just 10% of this volume we would have to put away annually about 6 Gm3 (assuming that all of the gas is compressed at least to its critical point where its density is 0.47 g/mL). The current extraction of crude oil (nearly 4 Gt in 2005) translates to less than 5 Gm3. Sequestering a mere 1/10 of today’s global CO2 emissions (less than 3 Gt CO2) would thus call for putting in place an industry that would have to force underground every year the volume of compressed gas larger than or (with higher compression) equal to the volume of crude oil extracted globally by petroleum industry whose infrastructures and capacities have been put in place over a century of development. Needless to say, such a technical feat could not be accomplished within a single generation.
(Note to Smil: Well of course it “could” be accomplished within a single generation if we had a WWII mentality for dealing with the climate problem. But since we don’t, my point is moot.)
In June, BusinessWeek‘s “The Dirty Truth About Clean Coal” concluded:
The catch is that for now — and for years to come — “clean coal” will remain more a catchphrase than a reality …
Corporations and the federal government have tried for years to accomplish “carbon capture and sequestration.” So far they haven’t had much luck. The method is widely viewed as being decades away from commercial viability. Even then, the cost could be prohibitive: by a conservative estimate, several trillion dollars to switch to clean coal in the U.S. alone.
Then there are the safety questions. One large, coal-fired plant generates the equivalent of 3 billion barrels of CO2 over a 60-year lifetime. That would require a space the size of a major oil field to contain. The pressure could cause leaks or earthquakes, says Curt M. White, who ran the U.S. Energy Dept.’s carbon sequestration group until 2005 and served as an adviser until earlier this year. “Red flags should be going up everywhere when you talk about this amount of liquid being put underground.”
E&E News reported in June ($ub. req’d), ” Carbon storage technology is far from ready, utility execs warn”:
Efforts to characterize carbon capture and sequestration (CCS) technology as a viable short-term “cure-all” for coal-burning power plants’ greenhouse emissions have been “way overblown,” the outgoing chairman of the leading utility industry group said today.
“It is a technology that [scientists] are comfortable can work,” said Jeff Sterba, the Edison Electric Institute’s outgoing chairman and chief executive of Albuquerque-based PNM Resources. “But is it commercially deployable in 10 years? No.”
… Added Jim Rogers, Duke Energy’s CEO and a former institute chairman, “CCS as a magical technology that solves the carbon problem for coal plants is oversold … I think there is a lot to learn, and it is going to take us a lot longer for us to figure it out than a lot of us think.”
Ben Yamagata, director of the Coal Utilization Research Council, was interviewed by E&E News in June and said:
I think there is a tendency for both sides to over-exaggerate what’s possible from a technical perspective. Our view is that it’s important for political leaders to think about technology about development as a process of crawling, then walking, then running. And on the one side, I think in context of what Jim Rogers has said, there’s too much focus on the running at this point. And we really need to think about taking the first baby steps before we lope into a full-charge gallop on this stuff. And so I would say, yeah, I would agree that at least certain elements of it who want to have this happen very quickly have overblown the possibility of when all of this can happen, not can it happen, which is an important distinction here, but when it’s going to happen …
We have a plan that is a two-part program and it says we should have a much, much more robust, research, development, demonstration program, really on the order of magnitude of $17 to $20 billion dollars over the next 18 or 19 years.
In July, Coal journalist Jeff Goodell wrote in “Coal’s New Technology: Panacea or Risky Gamble?”:
Unfortunately, CCS is more fantasy than reality at the moment …
… given how quickly the price of renewable energy is falling (wind and large-scale concentrated solar power are already competitive with coal in some parts of the country), you have to wonder why anyone would go to the trouble of building a coal plant at all.
Jeff Goodell on Coal-is-Dirty.com,”How Clean Coal Cooks Your Brain”:
“Clean coal” is not an actual invention, a physical thing — it is an advertising slogan. Like “fat-free donuts” or “interest-free loans.”
… mining and burning coal remains one of the most destructive things human beings do on this earth. It destroys mountains, poisons water, pollutes the air, and warms the atmosphere. True, if you look at it strictly from the point of view smog-producing chemicals like sulfur dioxide, new coal plants are cleaner than the old coal burners of yore. But going from four bottles of whiskey a week down to three does not make you clean and sober.
The U.S. Department of Energy’s Office of Fossil Energy resources on Carbon Capture Research can be found here.
Finally, I have been assuming one wedge of CCS by 2050 in my full climate solution, but I think the next version will likely drop that down to half a wedge, or perhaps 0.5 +/- 0.5 — 0 to 1 wedge for CCS.