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Abstract: Over the past few years, several pieces of legislation have been introduced in Congress aimed at reducing US greenhouse (GHG) emissions by setting emission targets by specified years. One of the latest bills, America’s Climate Security Act of 2007 (S.2191) was introduced in October 2007 and sets a US GHG emissions target for 2050 that is 85% below the governments business-as-usual forecast. DOE/NETL has employed a multi-sector emissions accounting tool, CarBen, that identifies emission abatement options and their contribution, via a wedge analysis, to the total GHG emissions reduction needed to meet the 2050 emissions target laid out in S.2191. This paper begins with a review of expected greenhouse (GHG) emissions in the United States through 2050. Historical and projected trends in U.S. energy use per GDP and GHG emission per unit of energy delivered are assessed. The paper then explores “technical possibilities” that exist for the U.S. to mitigate its GHG emissions in line with S.2191. Within the power sector, these options include nuclear power, renewable power generation, refurbishing existing coal power plants, retrofitting existing coal power plants with carbon capture and storage (CCS) and deploying new coal and natural gas power plants with CCS Outside of the power sector abatement options cover non-CO2 GHG emissions abatement, terrestrial offsets, international credits, improved vehicle efficiency and electrification of the transportation sector through hybrid electric vehicles. The methodology for calculating the wedges and allocating emissions reduction among the different options is described. [Copyright &y& Elsevier]

Abstract: This paper provides a financial analysis for new supercritical pulverized coal plants with carbon capture and sequestration (CCS) that compares the effects of two relevant climate policies. First, an updated cost estimate is presented for new supercritical pulverized coal plants, both with and without CCS. The capital cost escalation of recent years can be attributed to rising materials, plant supply, and plant contractor constraints. This estimate is then compared with recent estimates from public sources. Second, several current and proposed public policies relevant to CCS are presented. Finally, a financial analysis is performed to evaluate the effectiveness of two likely US carbon regulations on deploying Nth-plant CCS technology. The major conclusion is that the leading US carbon cap-and-trade bills will likely not be sufficient to deploy CCS technology in a manner consistent with a 550 ppm CO2 stabilization scenario. A more aggressive carbon policy including CCS research, development, and demonstration must be considered to achieve this goal with significant CCS deployment. [Copyright &y& Elsevier]

Abstract: Plug-in hybrid electric vehicles (PHEVs) have the potential to be an economic means of reducing direct (or tailpipe) carbon dioxide (CO2) emissions from the transportation sector. However, without a climate policy that places a limit on CO2 emissions from the electric generation sector, the net impact of widespread deployment of PHEVs on overall US CO2 emissions is not as clear. A comprehensive analysis must consider jointly the transportation and electricity sectors, along with feedbacks to the rest of the energy system. In this paper, we use the Pacific Northwest National Laboratory MiniCAM model to perform an integrated economic analysis of the penetration of PHEVs and the resulting impact on total US CO2 emissions. Under the assumptions used in this analysis where PHEVs obtain 50–60% of the market for passenger and light-duty trucks, the ability to deploy PHEVs under the two climate policies modeled here results in 6000–7300 Mt CO2 of additional cost -effective emissions reductions from the US economy over the period 2005–2050. The additional demand for geologic CO2 storage created by the introduction of the PHEVs is approximately equal to the cumulative geologic CO2 storage demanded by two to three large 1000 MW IGCC+CCS power plants over a 50 -year period. The introduction of PHEVs into the US transportation sector, coupled with climate policies such as those examined here, can also reduce US demand for oil by 20–30% by 2050 compared to today’s levels. [Copyright &y& Elsevier]

Abstract: A core mission of the U.S. Department of Energy’s (DOE) Carbon Sequestration Program is to foster the development of commercially-ready technologies for CO2 capture and sequestration. An R&D program goal of 90% carbon capture, at an increase in the cost of electricity (COE) no greater than 10% above current state-of-the-art designs without capture, has been established for electric power generation from next-generation Integrated-Gasification Combined-Cycle (IGCC) plants. Advanced gas separation membranes for separating H2 from CO2 are one possible technology for achieving these goals. For IGCC CO2-capture applications, membranes will need to out-perform existing chemical and physical absorption processes. Gas separation membranes, however, can be integrated into a number of different locations in the IGCC process in addition to post water-gas-shift (WGS), the preferred location for current absorption technologies. Due to the many integration options possible, membranes could potentially be required to operate over a wide range of conditions. It is preferred that the membrane operate at pressures and temperatures normally encountered at that point in the IGCC flowsheet where it is being placed. And, clearly it is beneficial that the membrane be placed in a location with relatively high pressure in order to maximize separation. If this is possible, the feed and product gases need not be compressed/expanded or heated/cooled. In addition, membrane materials being considered, whether ceramic, metallic or polymeric, have physical and chemical limitations in regards to operating temperature and tolerance to various compounds that might be present in synthesis gas. It is therefore unlikely that one type of membrane will be able to perform over the entire range of conditions possible. In this paper, we identify preferred membrane locations and quantify performance requirements for a wide range of membrane materials currently under consideration for H2/CO2 separation. [Copyright &y& Elsevier]