Abstracts of Papers from Princeton University's Carbon…

   Abstracts of Papers

  from Princeton University's
  Carbon Mitigation Initiative


     To be presented at the
 Fourth Annual Conference on
Carbon Capture & Sequestration
       May 2-5, 2005
     Alexandria, Virginia
Princeton University's Carbon Mitigation Initiative (CMI) is a 10-year
program (2001-2010) addressing the long-term challenge of carbon
management from the perspectives of science, engineering, and public
policy. CMI intends to establish which carbon management strategies: 1)
will have the desired effect on atmospheric carbon and climate; 2) will be
safe and reliable with limited environmental impact; and 3) will involve
neither prohibitive economic costs nor prohibitive disruption of patterns of
energy consumption. Further information about CMI can be found at the
project website: www.princeton.edu/~cmi/.

Gathered here are the abstracts of nine papers that CMI researchers are
presenting to the Fourth Annual Conference on Carbon Capture and
Sequestration, May 2-5, 2005, Alexandria, Virginia.


Robert Socolow and Stephen Pacala
March 2005
                               Table of Contents
      Author(s)                                  Title                           Page

M.A. Celia              Modeling Critical Leakage Pathways in a Risk               1
S. Bachu                Assessment Framework: Representation of Abandoned
J. Nordbotten           Wells
D. Kavetski
S. Gasda

Andrew Duguid           Degradation of Well Cements Exposed to Carbonated          2
Mileva Radonjic         Brine
George Scherer

Jeffery B. Greenblatt   "Wedge" analysis of stabilization scenario based on        3
Robert H. Socolow       SRES
Keywan Riahi

Roberta Hotinski        The "Stabilization Wedge" Game: A Tool for                 4
Sarah Wade              Communicating the Scale of the Greenhouse Gas
                        Problem

Eric D. Larson          Gasification-Based Liquid Fuels and Electricity from       5
Haiming Jin             Biomass with Carbon Capture
Robert H. Williams
Fuat E. Celik

Thomas G. Kreutz        A Potential for "Slipstream" H2 from Coal IGCC with        6
                        CO2 Capture and Storage in an Emerging H2
                        Economy for Transportation

Mohammad Piri           Carbon Dioxide Sequestration in Saline Aquifers:           7
Jean H. Prevost         Evaporation, Precipitation and Compressibility Effects
Richard Fuller

Robert H. Williams      Cost-Competitive, Low-GHG-Emitting Synthetic Liquid        8
                        Fuels via Coordinated Energy Production with CO2
                        Capture and Storage from Coal and Biomass

Kyle Meng               Opportunities for Low-Cost CO2 Capture and Storage         9
Michael Celia           Demonstration Projects in China
Robert H. Williams
          Modeling Critical Leakage Pathways in a Risk Assessment Framework:
                           Representation of Abandoned Wells

                 M.A. Celia1, S. Bachu2, J. Nordbotten3, D. Kavetski1, S. Gasda1



        In many locations in North America, likely injection sites for CO2 storage in deep
geological formation are located in mature sedimentary basins. These basins have a century-long
history of oil and gas exploration and production, which has led to hundreds of thousands (the
Alberta Basin) to millions (West Texas) of wells being drilled. The spatial density of these wells
is on the order of 1 to 10 wells per square kilometer. Therefore a typical injection will produce a
CO2 plume that intersects hundreds of existing wells, many of which are abandoned and some of
which have uncertain or unknown locations. In order to analyze the leakage potential in such
situations, computational models must be developed that can cover large spatial areas (of order
1,000 km2) while resolving the local dynamics in all of the hundreds of wells. In addition, the
layered structure of the subsurface, and possible leakage along wells and into successive
permeable layers in the subsurface, also need to be represented. We have developed a
semianalytical model that can simulate all of these attributes, over decadal to century time scales,
while running quickly on a laptop computer. With this tool, risk assessment based on Monte
Carlo analysis can be carried out. In this presentation, we will present an overview of the model,
and then demonstrate its applicability by modeling a potential injection site in the Alberta Basin
involving more than 500 existing wells over a domain that is 900 km2. Different leakage
measures and statistics will be presented.




Back to TOC




1
  Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544
USA. Email addresses: celia@princeton.edu, sgasda@princeton.edu,
kavetski@princeton.edu.
2
  Alberta Energy and Utilities Board, Edmonton, Alberta, T6B 2X3 Canada. Email address:
Stefan.Bachu@gov.ab.ca
3
  Department of Mathematics, University of Bergen, Bergen 5020, Norway.
Email: janmn@mi.uib.no




                                                 1
                Degradation of Well Cements Exposed to Carbonated Brine

                    Andrew Duguid, Mileva Radonjic, and George Scherer
                     Department of Civil and Environmental Engineering,
                                   Princeton University,
                               Princeton, New Jersey 08544.


        Subsurface carbon sequestration has the potential to help reduce anthropogenic CO2
emissions. If carbon sequestration in abandoned petroleum fields is adopted on a large scale, it
will be important to understand potential leakage pathways CO2 may take back to the
atmosphere. One leakage pathway is by degradation of the cement that is used to seal the
annulus between the well casing and the formation during construction and/or the degradation of
the cement that is used to plug the well when it is abandoned.

        A series of experiments were conducted to examine the degradation of Class H well
cement under sequestration-like conditions. Cement samples were reacted using carbonated
brine (NaCl solution) at room temperature and 50C between pH 2.4 and 7. The samples were
monitored throughout the course of the experiments. Data on effluent pH and composition were
collected using a pH probe and ICP-OES. The rate of advance of different leaching fronts within
the cement samples were calculated using measurements from optical microscope observations
and physical measurement of the samples. Data showing changes in composition of the reacted
cements were collected using X-ray diffraction and EPMA analysis.




Back to TOC




                                               2
                  "Wedge" analysis of stabilization scenario based on SRES

                   Jeffery B. Greenblatt1, Robert H. Socolow2, Keywan Riahi3




        We have examined two new questions with four of the well-known "business as usual"
(BAU) scenarios (A1B, A2, B1, and B2) from the IPCC Special Report on Emissions Scenarios
(SRES) generated by the MESSAGE model. First, we compare their emissions with the much
greater emissions that would occur if emissions were proportional to economic growth after Year
2000, and apportion the difference in CO2 emissions savings among three sources: carbon
content of fossil energy, non-fossil energy, and energy efficiency. All four scenarios exhibit large
autonomous changes in non-fossil energy and energy efficiency, and lesser contributions from
changes in fossil carbon content. Emissions reductions are 37-68% in 2050. Borrowing
vocabulary from a recent paper in Science, we identify the Year 2050 savings with specific
numbers of "virtual stabilization wedges," calling them "virtual" inasmuch as they occur without
deliberate carbon policy. We then compare three of the four BAU scenarios with variants ("post-
SRES" scenarios) developed using the same MESSAGE model, which stabilizes atmospheric
CO2 at 550 ppm after 2100. (The B1 scenario stays below 550 ppm without explicit mitigation
activity.) We apportion the carbon abatement through 2050 to carbon sequestration, carbon
content of fossil fuels, non-fossil energy, energy efficiency, and changes in economic output,
identifying "real stabilization wedges."




Back to TOC




1
  Princeton Environmental Institute, Princeton University, Princeton, New Jersey, 08540, USA.
E-mail: jgreenbl@princeton.edu
2
  Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New
Jersey, 08540, USA. E-mail: socolow@princeton.edu
3
  International Institute for Applied Systems Analysis (IIASA), A-2361 Laxenburg, Austria.
E-mail: riahi@iiasa.ac.at




                                                 3
       The "Stabilization Wedge" Game: A Tool for Communicating the Scale of the
                               Greenhouse Gas Problem

                               Roberta Hotinski1 and Sarah Wade2



        Productive discussion over how to address climate change can be thwarted by the
public's perception that the scale of the emissions cuts needed to avoid dramatic climate
change is impossibly large, or that individual technologies can serve as "magic bullets" to
fix the problem in the future.

        The "Stabilization Wedge" game developed at Princeton University addresses these
misperceptions. First, it simplifies the confusing landscape of emissions scenarios and
stabilization targets by considering just two future paths over the next 50 years - one
"business-as-usual" scenario in which carbon emissions double, and a flat emissions path
that avoids a doubling of atmospheric CO2. Second, it asks players to develop a strategy
to reduce emissions from the business-as-usual to the flat emissions trajectory using
currently available technologies.

       By illustrating the scale of the effort needed to avoid dramatic climate change, the game
allows participants to compare the capacities of different mitigation options and shows
the need for a portfolio of carbon-cutting strategies. It also catalyzes productive
discussion about the tradeoffs among various strategies, including costs and possible
negative impacts.

        The Stabilization Wedge Game has now been played successfully in several settings with
participants from a variety of backgrounds (e.g. academic, business, policy). We believe
that the game could be used as a means of educating a variety of audiences about the full
array of carbon-cutting options currently available, and that it could be used to promote
productive and constructive discussions of climate change policy.


Back to TOC




1
  Information Officer, Carbon Mitigation Initiative, Princeton Environmental Institute, Princeton
University, Princeton, NJ 08542. Email: hotinski@princeton.edu
2
   Partner, AJW, Inc., 1730 Rhode Island Ave., NW, Suite 700, Washington, DC, 20036. Email:
swade@ajwgroup.com




                                                4
    Gasification-Based Liquid Fuels and Electricity from Biomass with Carbon Capture

               Eric D. Larson1, Haiming Jin2, Robert H. Williams3, Fuat E. Celik4



        Sustainably produced biomass is an essentially carbon-neutral energy source since the
CO2 emitted from its use as energy had been absorbed from the atmosphere during growth, and
will be subsequently re-absorbed by future growth. By capturing and storing below ground some
carbon from biomass during its conversion to fuel or electricity, this biomass becomes a negative
CO2-emitting energy resource. We present detailed mass/energy balances and cost estimates for
alternative plant designs for making liquid fuels and/or electricity from biomass, with or without
carbon capture and storage (CCS). The feedstock is sustainably produced switchgrass, a
perennial grass native to the U.S. Great Plains. We consider alternative designs for production of
Fischer-Tropsch fuels and dimethyl ether (DME) with varying levels of electricity co-production.
We also consider stand-alone electricity production, with and without CCS. Because we are
interested in understanding the long-term potential for biomass energy, we assume that key
expected advances in thermochemical biomass conversion (feeding to a pressurized gasifier,
reliable high-efficiency oxygen-blown gasification, complete tar cracking and gas cleanup) are,
in fact, achieved. Also, we estimate costs assuming commercially mature Nth plants. All
performance results are based on consistent and detailed Aspen Plus process simulations. Capital
cost estimates are developed by major plant area based on a database developed in prior work,
literature studies, and discussions with industry experts. Using our performance and cost
estimates, we examine the overall economics of fuels and power production from switchgrass
with and without CCS, including the impact of possible carbon taxes.




Back to TOC




1
  Research Engineer, Princeton Environmental Institute, Princeton University, Princeton, New
Jersey, elarson@princeton.edu, ph: 609-258-4966
2
  Research Associate, Thayer School of Engineering, Dartmouth College, Hanover, New
Hampshire, Haiming.Jin@dartmouth.edu, ph: 603-646-9995
3
  Senior Research Scientist, Princeton Environmental Institute, Princeton University, Princeton,
New Jersey, rwilliam@princeton.edu, ph: 609-258-5448
4
  Research Assistant, Princeton Environmental Institute, Princeton University, Princeton, New
Jersey, fecelik@alumni.princeton.edu



                                                5
A Potential Role for "Slipstream" H2 from Coal IGCC with CO2 Capture and Storage in an
                         Emerging H2 Economy for Transportation

                                     Thomas G. Kreutz
                   Princeton Environmental Institute, Princeton University
                             25 Guyot Hall, Princeton, NJ 08544
              Phone: (609) 258-5691, Fax: (609) 258-7715, kreutz@princeton.edu

        Large capital-intensive energy conversion facilities generally require high load factors to
achieve favorable economic performance; this typically implies high and relatively constant
demand profiles. For this reason, large centralized H2 production plants are not well matched to
the decentralized and variable H2 demand characteristic of a nascent "H2 economy" in the
transportation sector. It is widely believed that small scale distributed H2 production
technologies such as natural gas steam reforming (SMR), located at H2 refueling terminals, will
be the most economical method of providing H2 to vehicles. Unfortunately, this model fails to
satisfy two key drivers for the H2 economy: low CO2 emissions and increased energy supply
security.

         We describe an alternative model of H2 production and distribution based on relatively
large, centralized sources of decarbonized H2 from slipstreams of synthesis gas generated in coal
integrated gasification combined cycle (IGCC) power plants with CO2 capture and storage
(CCS). We have investigated the design and economics of integrated systems that include
syngas production, H2 purification, compression, buffer storage, compressed gas distribution
(via pipeline or truck), and delivery at refueling stations. The delivered cost of "slipstream" H2
is found to be quite competitive with that of H2 from distributed SMR. Furthermore, the cost is
fairly insensitive to the amount produced (when the fraction of extracted syngas is relatively
small,