13 September 2014
Toward Getting the Global CCS Enterprise
Back on Track
Robert H. Williams (Princeton Environmental Institute, Princeton University)
and
LI Zheng (Thermal Engineering Department, Tsinghua University)
1
13 September 2014
The CCS Imperative for a Low Carbon Future
Deep reductions in GHG emissions will not be possible for fossil energy without widespread adoption of
carbon capture and storage (CCS) technologies. Moreover, deep decarbonization of the global energy
system is likely to be much more costly and perhaps less feasible without CCS as a viable carbonmitigation option. According to the
Intergovernmental Panel on Climate
Change (IPCC)) [1], the estimated
median cost increase to society of
realizing by 2100 a global energy
future consistent with an atmospheric CO2e concentration of 450
ppm (roughly equivalent to limiting
the global temperature rise to 2 oC—
which henceforth will be referred to
as 2DS—a 2 oC global energy
scenario) would be more than 130%
higher without than with CCS. The
corresponding cost increases would
be less than 10% if there were a
nuclear power phase out or if solar
and wind opportunities were limited
to 20% of electricity (see Figure 1).
Figure 1: Relative increase in the net present value of mitigation
costs (2015–2100, discounted at 5% per year) from technology
portfolio variations relative to a scenario with default technology
assumptions, as estimated using alternative integrated
assessment models [1].
The dark horizontal bars in each column represent the median increased
mitigation cost for each stabilization scenario, as estimated using these
integrated assessment models. The discussion in the main text is focused
on the estimated median cost increases for the blue bars, which represent
a global energy future consistent with 2 oC warming.
Scenario names on the horizontal axis indicate the technology variation
relative to default assumptions: NO CCS: unavailability of CCS; Nuclear
Phase Out: no additional nuclear power plants beyond those under
construction and existing plants are operated until the end of their
lifetimes; Limited Solar/Wind: 20% limit on solar and wind electricity
generation; Limited Bioenergy: maximum of 100 EJ per year of bioenergy
supply (Figure TS 13 from the Technical Summary of [1].
The need for CCS to enable a lowcarbon energy future extends beyond
fossil energy conversion, especially
for energy futures in which global
emissions do not decline immediately
at high rates. For such energy paths
future options characterized by “net
negative” emissions will be needed to
offset emissions “overshoot” in the
near term. A promising set of such
negative emissions options involves
making useful energy from biomass
grown sustainably in systems with
CCS: uptake of atmospheric CO2
through biomass growth, in combination with carbon capture and
subsequent underground CO2
storage, leads to negative emissions.
The Faltering Global CCS Enterprise
There has been substantial progress
in evolving CCS technologies. Whereas at the turn of the century there was only one operating CCS
project and little industry or government investment in R&D, and no financial incentives to promote
CCS, the situation has since improved markedly: governments and industry have committed tens of
billions of dollars for R&D, scale-up and deployment [2]. As of the end of 2013 there were 12 large2
13 September 2014
scale, integrated CCS projects in operation; eight additional projects are in construction [3]. The first
three commercial-scale power projects with CCS are scheduled to come on line during 2014-20161.
But what has been accomplished falls far short of what is needed to realize a 2DS: the 20 large-scale
integrated CCS projects already operating or under construction are only 1/5 of the number of such
projects that the International Energy Agency estimated in 2009 should be up and running by 2020 in
order to realize such an energy future [4].
High costs of early-mover CCS energy projects and the absence of a motivating high price on GHG
emissions are major reasons that progress on CCS has been slower than anticipated. Present CCS costs
are too high to make early-mover CCS projects based on current technologies profitable to the private
sector. The cost barrier to near-term market launch of promising CCS technologies is especially daunting
in the US, where there is not only Congressional gridlock on advancing low-carbon energy technologies
but also where the shale gas boom has created an electricity market in which the current market price
of electricity (set, in essence, by the low market price of natural gas) is low.
Although significant cost reductions are expected as a result of experience—e.g., the Alberta CCS
Development Council believes there is
scope for about a 40 per cent reduction
in CCS project costs to be delivered
over a 10- to 15-year technology
lifecycle, culminating in full
commercialization [5], uncertainties
relating to future carbon-mitigation
policies inhibit entrepreneurs from
exploiting this prospect by pursuing
forward-pricing strategies to gain the
technological edge in establishing CCS
Figure 2: Carbon Budgets in Relation to Fossil Fuel Reserves
technologies in the market.
8000
7000
6000
High estimate of atmospheric CO2 budget
Gt CO2
5000
Low estimate of atmospheric CO2 budget
4000
Natural gas
3000
Ave: 1705
Oil
Coal
Ave: 1255
2000
Ave: 905
1000
0
Reserves
Reserves
90 years
(low estimate) (high estimate) consumption at
2010 rate
450 ppm
budget
500 ppm
budget
550 ppm
budget
Three right-most bars: atmospheric CO2 emissions budgets (20112100) consistent with stabilization of GHGs at 450, 500, and 550
ppm CO2e from Table 6.2 of [1].
Two left-most bars: CO2 emissions associated with burning low
and high estimates of remaining fossil fuel reserves as estimated
in Table 7.1 of [6]; reserves are supplies that are profitably
recoverable with current technologies and current fossil fuel
prices; additional fossil fuel resources would become reserves
with advanced technologies and/or higher prices.
Third-bar: Cumulative CO2 emissions by source, 2011-2100, if
annual emissions continued at the 2010 rate [7]; comparing this
bar with the bars on the right implies that the average annual
emission rate, 2011-2100, must be reduced to 58%, 43%, or 31%
of the 2010 rate if the 550, 500, or 450 ppm CO2e stabilization
level is to be realized (assuming average carbon budgets).
1
The Urgency of Getting the Global CCS
Enterprise Back on Track
IPCC scientists have drawn attention to
the carbon budgets associated with
alternative GHG stabilization levels to
stress to governments the urgency of
enacting comprehensive carbon
mitigation policies. Comparison of
these carbon budgets to fossil fuel
reserves should convince all fossil fuel
providers of the urgency of getting the
CCS enterprise back on track. Figure 2
compares fossil fuel reserves and
Significant milestones will be realized when the first three commercial-scale power projects with CCS come on line—expected
during 2014-2016: the 110 MWe coal post-combustion rebuild Boundary Dam Project in Canada; the 582 MWe new precombustion coal IGCC-CCS project in Kemper County, Mississippi; and the 240 MWe Petra Nova coal post-combustion retrofit
project in Texas—all of which will sell captured CO2 into EOR markets. Moreover, a 385 MWe NGCC-CCS project is being
planned at Peterhead, Scotland, that would store CO2 in a depleted natural gas reservoir under the North Sea; if that project
goes forward, it could begin storing CO2 in the 2018-2020 time frame.
3
13 September 2014
remaining CO2 emissions through 2100 that would be consistent with stabilizing the GHG concentration
in the atmosphere at 550 ppmv (1.7 trillion tonnes of CO2), 500 ppmv (1.3 trillion tonnes), and 450 ppmv
(0.9 trillion tonnes)…the last of these representing a 2DS. In all cases, the “carbon budget” is much less
than the estimated remaining fossil fuel reserves (the combustion of which would release 3.6 to 7.1
trillion tonnes of CO2).
That the highest CCS priority should be advancing CCS for coal energy conversion is clear from coal market activity. Industrialized countries, where electricity demand is practically flat, are not adding much if
any new coal electric generating capacity, but developing countries are adding more than 60 GWe of
new coal generating capacity annually2. If this much annual added capacity is operated for 50 years
without CCS it would add 18 Gt of CO2 to the atmosphere—equivalent to 1.9 – 2.9 percent of oil
reserves (Figure 2). This simple calculation can be interpreted as meaning that each year’s addition of
new world coal capacity without CCS could plausibly lead to keeping up to 1.9 – 2.9 percent of oil
reserves in the ground under a carbon cap. Thus even oil companies should recognize the urgency of
getting the global CCS enterprise back on track.
A Strategy to Help Get the Global CCS Enterprise Back on Track
A promising approach to getting the global CCS enterprise back on track is to focus over the next decade
on low-cost CCS opportunities based on technologies near at hand while simultaneously carrying out
R&D on advanced CCS technologies for the longer term. One set of such near-term opportunities
involves storing CO2 in conjunction with enhanced oil recovery (CO2 EOR), a commercially established
technology for which providers get paid for captured CO2; CO2 EOR opportunities can be exploited to
gain experience with and thereby (via learning by doing) reduce costs of promising CO2 capture
technologies. Another involves gaining extensive experience with CO2 storage (in deep saline
formations as well as via EOR) by capturing streams of nearly pure CO2 that are currently vented at
chemical and synfuel plants.
Capture technology cost buydown in US CO2 EOR market applications under an AEPS
The opportunities for “capture technology cost buy-down” through experience are especially large in
the US, home of most of world CO2 EOR activity. In the US the CO2 storage potential via EOR is sufficient
to support ~ 100 large-scale early-mover CCS projects [9, 10]. But even with the CO2 EOR opportunity,
costs for early-mover projects are likely to be so large that projects are not likely to go forward unless
supported by appropriate new public policies for at least the first few projects.
A powerful public policy environment for supporting early CCS projects linked to EOR in the US could be
provided via a slight amendment [11] of the US Environmental Protection Agency’s proposed Existing
Source Performance Standard (ESPS) for regulating CO2 emissions from existing power plants (see Box A)
that would allow a state or region, in carrying out its ESPS obligations, to: (a) include CCS with CO2 sold
for EOR as an additional ESPS Building Block (see Box A for a discussion of Building Blocks already
proposed by the EPA), and (b) use an Alternative Energy Portfolio Standard (AEPS) as its preferred policy
instrument for ESPS implementation. The AEPS [a technology-neutral variant of the familiar Renewable
Portfolio Standard (RPS)] would mandate up to a target date the provision of a growing amount of low
carbon electricity, and the market would choose a mix of low-carbon electric generating technologies
from among those that would compete to satisfy the mandate. The AEPS would provide the mechanism
for technology cost buydown (TCB), as is the case for the RPS.
2
According to [8], coal electric generating capacity in 2020 in non-OECD countries will be, under current policies, 1632 GWe, up
from 1074 GWe in 2011. In essence, in this period non-OECD countries are adding the equivalent of total US coal generating
capacity every five years.
4
13 September 2014
The proposed ESPS in its present form will not be helpful in advancing CCS and would probably slow CCS
development [12]. However, the recommended amendment to the ESPS [11] could transform the ESPS
into an instrument for advancing CCS via TCB under the proposed state- or region-based AEPS.
Box A: The EPA’s Proposed ESPS for Regulating CO 2 Emissions from Existing Power Plants
On 2 June 2014 the US Environmental Protection Agency (EPA) proposed a new regulation of CO2 emissions from
existing power plants with an overarching goal of reducing CO2 emissions from US power plants in 2030 by 30%
relative to emissions in 2005. The proposed Existing Source Performance Standard (ESPS) requires each state to
submit a plan that it would pursue to meet that state’s obligations as set by the EPA.
The proposed ESPS gives a state enormous flexibility in meeting its emissions reduction obligation by allowing
more carbon-mitigation options than just modification of existing power plants. The EPA suggested that states
might consider constructing their plans based on 4 Building Blocks: (1) investments to improve the energy
efficiency with which plants generate electricity, (2) operation of natural gas combined cycle power plants (which
emit less CO2 per MWh than coal plants) more and coal plants less, (3) substituting generation at existing power
plants with expanded low- or zero-carbon generation (e.g., wind and solar), and (4) improvement in the efficiency
of systems consuming electricity.
According to [13] both the natural gas combined cycle power with CCS based on post-combustion capture (NGCC-CCS) for “new build” applications and retrofits of old pulverized coal plants with postcombustion capture equipment (PC-CCS retrofit) could plausibly become successfully established in US
CO2 EOR markets after a small number of costly early-mover projects have been subsidized under an
AEPS3. As a result of cost reduction via experience (learning by doing) under this TCB process, these
technologies in CO2 EOR applications would be able to compete without continuing subsidy with NGCCV. However, [13] also shows that once the CO2 EOR market reaches saturation and CO2 storage for new
projects would be in deep saline formations (DSFs), for which there is no economic benefit except for
the economic value of carbon mitigation, these CCS technologies would not be able to compete in
power markets with NGCC-V until very high GHG emission prices are reached—price levels that are not
likely to be realizable in the US before 2030. But [13] urges that nonetheless it is worthwhile to carry
out TCB via an AEPS for these technologies because: (a) the US CO2 EOR storage opportunity is huge, so
that many EOR projects could be carried out; (b) including it in the TCB via an AEPS would make NGCCCCS ready for deployment in DSF applications in the US and elsewhere post-2030—when GHG emissions
prices are likely to be much higher than during the next decade; and (c) there will be huge markets for
PC-CCS retrofit technologies in developing countries, in many of which the competition from natural gas
facing coal will be not nearly so fierce as in the US.
In addition, [13] analyses the economics of TCB via an AEPS for gasification-based electricity generating
systems with CCS that provide synthetic liquid transportation fuels (diesel and gasoline via the FischerTropsch process) as major coproducts of electricity: both systems that process only coal (CTLE-CCS: coal
to liquids + electricity with CCS) and systems that coprocess biomass with coal (CBTLE-CCS: coal/biomass
to liquids + electricity with CCS) were considered. It was found that in CO2 EOR applications either of
these “coproduction” technologies could plausibly become competitive with NGCC-V after only two
plants have been subsidized via an AEPS policy. Moreover, [13] found that at zero or modest GHG
emissions prices mature versions of these technologies are also likely to be competitive in the US with
NGCC-V even when CO2 storage is in DSFs. The more favourable economics for these technologies
compared to power-only technologies arises because of: (a) the inherently much lower CO2 capture
costs for systems that make liquid fuels compared to capture costs for systems that make only
3
In addition, [13] shows that in the US, where electricity prices are low as a result of the shale gas revolution, coal integrated
gasification combined cycle (IGCC) technology with CCS is not a promising technology for TCB under an AEPS.
5
13 September 2014
coal upstream emissions
flue gases
vehicle tailpipe
fuel
photosynthesis
biomass upstream emissions
electricity, and (b) the large coproduct credits from selling liquid transportation fuels in a world of high
crude oil prices. CBTLE-CCS systems offer the opportunity to carry out CCS for biomass energy at much
lower GHG emissions prices than is feasible for “pure” biomass energy systems by exploiting the scale
economy benefits and lower average feedstock costs associated with coal/biomass coprocessing [13].
Moreover, considered as low-carbon fuel providers, CBTLE-CCS system require far less biomass per unit
of liquid fuel energy than pure biofuels—thereby enabling the production of much more low-carbon
liquid fuel from sustainable biomass, the supply of which is constrained by food/fuel conflicts and
concerns about biodiversity and other issues [14, 15, 16]. Finally, CBTLE-CCS offers the prospect of
reducing net GHG emissions for both electricity and liquid fuels to very low levels (e.g., the system
described in Figure 3 would be characterized by zero net GHG emissions) at relatively modest biomass
coprocessingCarbon
rates. flows for coal/biomass conversion
to fuels and electricity with CCS
Strategic opportunity for rapid growth
in CO2 storage experience in China
biomass
coal
CO2
storage
char
3
Figure 3: Carbon-equivalent flows to and from the atmosphere
for a CBTLE-CCS system coproducing electricity + synthetic
liquid fuels from coal + sustainable biomass (from [16])
The negative emissions arising from photosynthetic CO2 storage
when biomass is provided on a sustainable basis offset the positive emissions from coal-derived carbon. A CBTLE-CCS system
whose outputs are 30% electricity and 70% liquid transportation
fuels with capture and storage as CO2 of 66% of feedstock
carbon would have a net zero GHG emission rate when biomass
accounts for ~ 34% of feedstock energy: in that case the sum of
the upward Ce flows equals the downward Ce flow associated
with the recovery of carbon from the atmosphere during
photosynthesis, so that net GHG emissions for production and
use of electricity + liquid fuels would be zero.
As discussed in [13], CBTLE-CCS technologies cogasifying up to
30% biomass with low-rank coals are ready to be demonstrated
at commercial scale. After successful demonstration, CBTLE-CCS
systems coprocessing enough biomass (~ 25%) to realize more
than an 80% reduction in GHG emissions relative to displaced
fossil energy could be deployed during the next decade.
own countries.
6
China has an extraordinary opportunity
to develop extensive experience with
CO2 storage in deep saline formations as
well as via EOR at low cost as a result of
its having hundreds of existing and
planned chemical and synfuel projects
that vent streams of nearly pure CO2,
many of which are near potential CO2
storage sites (see Figure 4). Capturing
and transporting these CO2 streams and
storing the CO2 in suitable underground
reservoirs would represent some of the
least-costly CCS opportunities on the
planet.
Because such projects would not be
profitable in the absence of a significant
price on carbon emissions, co-financing
of early-mover projects by government
and industry is called for. What can be
learned about the challenges and
oppor-tunities of underground CO2
storage via such projects in China would
be widely applicable throughout the
world. Thus, consideration should be
given to multi-lateral collaboration for
such projects, including consideration of
technology sharing and co-financing.
Via such col-laborations, foreign
governments could gain early access to
what is learned in such projects,
facilitating potential applications in their
13 September 2014
7
13 September 2014
Figure 4: Sites of nearly pure CO2 emission streams from chemical/synfuel plants and prospective CO 2 storage
areas in China
The pins on this map are, for 2010, the ~ 400 existing/planned chemical/synfuel plants in China releasing
concentrated CO2 streams (low capture costs) to the atmosphere; the large pins represent large CO2 sources. The
green areas are sedimentary basins where suitable storage sites might be found.
An economic screening analysis of possible large-scale CCS projects represented by the large pins in this figure
was carried out in [17]. Since the publication of [17], the process of generating nearly pure CO2 streams via coal
energy conversion has continued to grow in China—much of this activity has involved construction of substitute
natural gas (SNG) plants as a strategy for mitigating the severe public health damages from ambient PM2.5 air
pollution associated with coal burning [18, 19]. The rationale for this strategy is that: (a) replacing coal with SNG
for heating, cooking virtually eliminates PM2.5 air-pollution health damage concerns, (b) gasification-based coal to
SNG technology is commercially proven, and (c) China has the most global experience with coal energy
conversion via gasification. As of the end of 2013 some 30 SNG plants had been proposed, 9 of which projects
had been approved by the Chinese government [19]. For these coal to SNG projects, CCS is currently not being
planned—a result of which is that the CO2 emissions would increase at the same time PM2.5 air pollutant
emissions and associated adverse health would decrease when the direct burning of coal is replaced by coalderived SNG. However, as in the case of chemicals and synthetic liquid fuel plants, most of the emissions from
these plants are in streams of nearly pure CO2, the capture of which can be realized at low cost. Moreover, if the
direct burning of coal in buildings and industry were replaced by SNG derived from coal in plants with CCS, the
net result would be a significant reduction in CO2 emissions along with the substantial reduction in PM2.5 air
pollutant emissions.
8
13 September 2014
References
[1] WG III. Climate Change 2014: Mitigation of Climate Change, Working Group III contribution to the 5 th
Assessment Report of the Intergovernmental Panel on Climate Change, April 2014.
[2] Benson SM (convening lead author) and Bennaceur K, Cook P, Davison J, de Coninck H, Farhat K, Ramirez A,
Simbeck D, Surles T, Verma P, and Wright I (lead authors). Carbon capture and storage, Chapter 13, pp. 993-1068,
in Global Energy Assessment: Toward a Sustainable Future, Cambridge University Press, Cambridge, 2012.
[3] GCCSI. Global Status of CCS 2013, Global CCS Institute, Melbourne, Australia, 2013.
[4] IEA. Technology Roadmap: Carbon Capture and Storage, International Energy Agency, OECD/IEA, Paris, 2009.
[5] Alberta CCS Development Council. Accelerating Carbon Capture and Storage Implementation in
Alberta, Final Report, Canada, March 2009. Available online at
http://www.energy.gov.ab.ca/Org/pdfs/CCS_Implementation.pdf
[6] Rogner HH (convening lead author) and Aguilera RF, Archer CL, Bertani R, Bhattacharya SC, Dusseault MB,
Gagnon L, Haberl H, Hoogwijk M, Johnson A, Rogner ML, Wagner H, and Yakushev V (lead authors). Energy
resources and potentials, Chapter 7, pp. 425-512, Global Energy Assessment: Toward a Sustainable Future,
Cambridge University Press, Cambridge, 2012.
[7]. EIA. International Energy Outlook 2013 with Projections to 2040, Energy Information Administration.
Washington DC, July 2013.
[8] IEA. World Energy Outlook 2013, International Energy Agency, OECD/IEA, Paris, 2013.
[9] NETL. Improving Domestic Energy Security and Lowering CO2 Emissions with “Next Generation” CO2-Enhanced
Oil Recovery (CO2-EOR), National Energy Technology Laboratory, DOE/NETL-2011/1504 Activity 04001.420.02.03,
June 2011.
[10] ARI. US Oil Production Potential from Accelerated Deployment of Carbon Capture and Storage, a report
prepared by Advanced Resources International for the Natural Resources Defense Council, 10 March 2010.
[11] Williams RH. Public Comment on the Environmental Protection Agency’s proposed regulation on CO2
emissions for existing power plants, forthcoming.
[12] Carter LD. Meeting Global Carbon Reduction Goals: A Technology Driven Paradigm, Institute for Carbon
Management, School of Natural Resources, University of Wyoming, 13 August 2014.
[13] Williams RH. Capture technology cost buydown in CO2 EOR market applications under an Alternative Energy
Portfolio Standard. Proceedings of the 12th International Conference on Greenhouse Gas Control Technologies,
Energy Procedia, Elsevier, October 2014.
[14] Larson ED and Li Z (convening lead authors) and Williams RH (lead author). Fossil energy, Chapter 12, pp. 901992, in Global Energy Assessment: Toward a Sustainable Future, Cambridge University Press, Cambridge, 2012.
[15] Williams RH. Coal/biomass coprocessing strategy to enable a thriving coal industry in a carbon-constrained
world. Cornerstone, 2013; 1 (1), 51–59.
[16] Larson ED, Fiorese G, Liu G, Williams RH, Kreutz TG, and Consonni S. Co-production of synfuels and electricity
from coal + biomass with zero net greenhouse gas emissions: an Illinois case study, Energy and Environmental
Science 2010; 3: 28-42.
[17] Zheng Z, Larson ED, Li Z, Liu G, and Williams RH. Near-term mega-scale CO2 capture and storage
demonstration opportunities in China,” Energy and Environmental Science 2011; 3: 1153-1169.
[18] Ding Y, Han W, Chi Q, Yang S, and Shen W. Coal-based synthetic natural gas (SNG): A solution to China’s
energy security and CO2 reduction? Energy Policy 2013; 55: 445-453.
[19] Yang, CJ, and Jackson RB. China’s synthetic natural gas revolution. Nature Climate Change 2013; 3: 852-854,
October.
9