WorldWideScience

Sample records for co2 reduction potential

  1. CO2 emissions and reduction potential in China's chemical industry

    International Nuclear Information System (INIS)

    Zhu, Bing; Zhou, Wenji; Hu, Shanying; Li, Qiang; Griffy-Brown, Charla; Jin, Yong

    2010-01-01

    GHG (Increasing greenhouse gas) emissions in China imposes enormous pressure on China's government and society. The increasing GHG trend is primarily driven by the fast expansion of high energy-intensive sectors including the chemical industry. This study investigates energy consumption and CO 2 emissions in the processes of chemical production in China through calculating the amounts of CO 2 emissions and estimating the reduction potential in the near future. The research is based on a two-level perspective which treats the entire industry as Level one and six key sub-sectors as Level two, including coal-based ammonia, calcium carbide, caustic soda, coal-based methanol, sodium carbonate, and yellow phosphorus. These two levels are used in order to address the complexity caused by the fact that there are more than 40 thousand chemical products in this industry and the performance levels of the technologies employed are extremely uneven. Three scenarios with different technological improvements are defined to estimate the emissions of the six sub-sectors and analyze the implied reduction potential in the near future. The results highlight the pivotal role that regulation and policy administration could play in controlling the CO 2 emissions by promoting average technology performances in this industry.

  2. CO2 substitution potential and CO2 reduction costs of an energetic exploitation of solid biomasses in Germany

    International Nuclear Information System (INIS)

    Becher, S.

    1995-01-01

    For the reduction of the anthropogenic greenhouse effect, the CO 2 , emissions are clearly to be reduced in future, according to the resolution made by the Federal Republic. Against the background of this objective, possible contributions of the biogenous solid fuels for the reduction of the CO 2 release of fossil origin are presented and discussed. For that, first the existing potentials of biomass in Germany and their present use are shown. Based on this, the CO 2 emissions by the present use already avoided, as well as the existing unexploited potentials of the CO 2 reduction potentials still to be exploited are determined. In accordance with an 'integral' starting point, thereby all pre- and post-positioned processes are considered. Finally, the specific CO 2 reduction costs are analysed and compared with other options. (orig.) [de

  3. Stockholm CHP potential - An opportunity for CO2 reductions?

    International Nuclear Information System (INIS)

    Danestig, Maria; Gebremehdin, Alemayehu; Karlsson, Bjoern

    2007-01-01

    The potential for combined heat and power (CHP) generation in Stockholm is large and a total heat demand of about 10 TWh/year can be met in a renewed large district heating system. This model of the Stockholm district heating system shows that CHP generation can increase from 8% in 2004 to 15.5% of the total electricity generation in Sweden. Increased electricity costs in recent years have awakened an interest to invest in new electricity generation. Since renewable alternatives are favoured by green certificates, bio-fuelled CHP is most profitable at low electricity prices. Since heat demand in the district heating network sets the limit for possible electricity generation, a CHP alternative with a high electricity to heat ratio will be more profitable at when electricity prices are high. The efficient energy use in CHP has the potential to contribute to reductions in carbon dioxide emissions in Europe, when they are required and the European electricity market is working perfectly. The potential in Stockholm exceeds Sweden's undertakings under the Kyoto protocol and national reduction goals. (author)

  4. Potential energy savings and CO2 emissions reduction of China's cement industry

    International Nuclear Information System (INIS)

    Ke, Jing; Zheng, Nina; Fridley, David; Price, Lynn; Zhou, Nan

    2012-01-01

    This study analyzes current energy and carbon dioxide (CO 2 ) emission trends in China's cement industry as the basis for modeling different levels of cement production and rates of efficiency improvement and carbon reduction in 2011–2030. Three cement output projections are developed based on analyses of historical production and physical and macroeconomic drivers. For each of these three production projections, energy savings and CO 2 emission reduction potentials are estimated in a best practice scenario and two continuous improvement scenarios relative to a frozen scenario. The results reveal the potential for cumulative final energy savings of 27.1 to 37.5 exajoules and energy-related direct emission reductions of 3.2 to 4.4 gigatonnes in 2011–2030 under the best practice scenarios. The continuous improvement scenarios produce cumulative final energy savings of 6.0 to 18.9 exajoules and reduce CO 2 emissions by 1.0 to 2.4 gigatonnes. This analysis highlights that increasing energy efficiency is the most important policy measure for reducing the cement industry's energy and emissions intensity, given the current state of the industry and the unlikelihood of significant carbon capture and storage before 2030. In addition, policies to reduce total cement production offer the most direct way of reducing total energy consumption and CO 2 emissions. - Highlights: ► This study models output and efficiency improvements in Chinese cement industry from 2011–2030. ► Energy savings and CO 2 emission reductions estimated for 3 scenarios relative to frozen scenario. ► Results reveal cumulative final energy savings potential of 27.1–37.5 EJ and 3.2–4.4 Gt CO 2 reductions. ► Increasing efficiency is the most important policy for reducing cement energy and emissions intensity.

  5. Assessment of Alternative Scenarios for CO2 Reduction Potential in the Residential Building Sector

    Directory of Open Access Journals (Sweden)

    Young-Sun Jeong

    2017-03-01

    Full Text Available The South Korean government announced its goals of reducing the country’s CO2 emissions by up to 30% below the business as usual (BAU projections by 2020 in 2009 and 37% below BAU projections by 2030 in 2015. This paper explores the potential energy savings and reduction in CO2 emissions offered by residential building energy efficiency policies and plans in South Korea. The current and future energy consumption and CO2 emissions in the residential building were estimated using an energy–environment model from 2010 to 2030. The business as usual scenario is based on the energy consumption characteristic of residential buildings using the trends related to socio-economic prospects and the number of dwellings. The alternative scenarios took into account energy efficiency for new residential buildings (scenario I, refurbishment of existing residential buildings (scenario II, use of highly efficient boilers (scenario III, and use of a solar thermal energy system (scenario IV. The results show that energy consumption in the residential building sector will increase by 33% between 2007 and 2030 in the BAU scenario. Maximum reduction in CO2 emissions in the residential building sector of South Korea was observed by 2030 in scenario I. In each alternative scenario analysis, CO2 emissions were 12.9% lower than in the business as usual scenario by the year 2030.

  6. Scenario analysis on CO2 emissions reduction potential in China's iron and steel industry

    International Nuclear Information System (INIS)

    Wang Ke; Wang Can; Lu Xuedu; Chen Jining

    2007-01-01

    The international climate community has begun to assess a range of possible options for strengthening the international climate change effort after 2012. Analysis of the potential for sector-based emissions reduction and relevant mitigation options will provide the necessary background information for the debate. In order to assess the CO 2 abatement potential of China's steel industry, a model was developed using LEAP software to generate 3 different CO 2 emission scenarios for the industry from 2000 to 2030. The abatement potentials of different scenarios were compared, and their respective feasibilities were assessed according to the cost information. High priority abatement measures were then identified. The results show that the average CO 2 abatement per year in the Recent Policy scenario and in the New Policy scenario, compared with the reference scenario, are 51 and 107 million tons, respectively. The corresponding total incremental costs are 9.34 and 80.95 billion dollars. It is concluded that there is great potential for CO 2 abatement in China's steel industry. Adjusting the structure of the industry and technological advancement will play an important role in emissions reduction. Successful implementation of current sustainable development policies and measures will result in CO 2 abatement at a low cost. However, to achieve higher levels of abatement, the cost will increase dramatically. In the near future, specific energy conservation technologies such as dry coke quenching, exhaust gas and heat recovery equipment will be of great significance. However, taking a long term perspective, emissions reduction will rely more on the adjustment of production processes and the application of more modern large scale plants. Advanced blast furnace technology will inevitably play an important role

  7. Cement replacement by sugar cane bagasse ash: CO2 emissions reduction and potential for carbon credits.

    Science.gov (United States)

    Fairbairn, Eduardo M R; Americano, Branca B; Cordeiro, Guilherme C; Paula, Thiago P; Toledo Filho, Romildo D; Silvoso, Marcos M

    2010-09-01

    This paper presents a study of cement replacement by sugar cane bagasse ash (SCBA) in industrial scale aiming to reduce the CO(2) emissions into the atmosphere. SCBA is a by-product of the sugar/ethanol agro-industry abundantly available in some regions of the world and has cementitious properties indicating that it can be used together with cement. Recent comprehensive research developed at the Federal University of Rio de Janeiro/Brazil has demonstrated that SCBA maintains, or even improves, the mechanical and durability properties of cement-based materials such as mortars and concretes. Brazil is the world's largest sugar cane producer and being a developing country can claim carbon credits. A simulation was carried out to estimate the potential of CO(2) emission reductions and the viability to issue certified emission reduction (CER) credits. The simulation was developed within the framework of the methodology established by the United Nations Framework Convention on Climate Change (UNFCCC) for the Clean Development Mechanism (CDM). The State of São Paulo (Brazil) was chosen for this case study because it concentrates about 60% of the national sugar cane and ash production together with an important concentration of cement factories. Since one of the key variables to estimate the CO(2) emissions is the average distance between sugar cane/ethanol factories and the cement plants, a genetic algorithm was developed to solve this optimization problem. The results indicated that SCBA blended cement reduces CO(2) emissions, which qualifies this product for CDM projects. 2010 Elsevier Ltd. All rights reserved.

  8. Evaluation of potential cost reductions from improved amine-based CO2 capture systems

    International Nuclear Information System (INIS)

    Rao, Anand B.; Rubin, Edward S.; Keith, David W.; Granger Morgan, M.

    2006-01-01

    Technological innovations in CO 2 capture and storage technologies are being pursued worldwide under a variety of private and government-sponsored R and D programs. While much of this R and D is directed at novel concepts and potential breakthrough technologies, there are also substantial efforts to improve CO 2 capture technologies already in use. In this paper, we focus on amine-based CO 2 capture systems for power plants and other combustion-based applications. The current performance and cost of such systems have been documented in several recent studies. In this paper we examine the potential for future cost reductions that may result from continued process development. We used the formal methods of expert elicitation to understand what experts in this field believe about possible improvements in some of the key underlying parameters that govern the performance and cost of this technology. A dozen leading experts from North America, Europe and Asia participated in this study, providing their probabilistic judgments via a detailed questionnaire coupled with individual interviews. Judgments about detailed technical parameters were then used in an integrated power plant modeling framework (IECM-CS) developed for USDOE to evaluate the performance and costs of alternative carbon capture and sequestration technologies for fossil-fueled power plants. The experts' responses have allowed us to build a picture of how the overall performance and cost of amine-based systems might improve over the next decade or two. Results show how much the cost of CO 2 capture could be reduced via targeted R and D in key areas

  9. Assessing the Potential of Utilization and Storage Strategies for Post-Combustion CO2 Emissions Reduction

    International Nuclear Information System (INIS)

    Armstrong, Katy; Styring, Peter

    2015-01-01

    The emissions reduction potential of three carbon dioxide handling strategies for post-combustion capture is considered. These are carbon capture and sequestration/storage (CCS), enhanced hydrocarbon recovery (EHR), and carbon dioxide utilization (CDU) to produce synthetic oil. This is performed using common and comparable boundary conditions including net CO 2 sequestered based on equivalent boundary conditions. This is achieved using a “cradle to grave approach” where the final destination and fate of any product is considered. The input boundary is pure CO 2 that has been produced using a post-combustion capture process as this is common between all processes. The output boundary is the emissions resulting from any product produced with the assumption that the majority of the oil will go to combustion processes. We also consider the “cradle to gate” approach where the ultimate fate of the oil is not considered as this is a boundary condition often applied to EHR processes. Results show that while CCS can make an impact on CO 2 emissions, CDU will have a comparable effect whilst generating income while EHR will ultimately increase net emissions. The global capacity for CDU is also compared against CCS using data based on current and planned CCS projects. Analysis shows that current CDU represent a greater volume of capture than CCS processes and that this gap is likely to remain well beyond 2020 which is the limit of the CCS projects in the database.

  10. Evaluating the CO 2 emissions reduction potential and cost of power sector re-dispatch

    Energy Technology Data Exchange (ETDEWEB)

    Steinberg, Daniel C.; Bielen, David A.; Townsend, Aaron

    2018-01-01

    Prior studies of the U.S. electricity sector have recognized the potential to reduce carbon dioxide (CO2) emissions by substituting generation from coal-fired units with generation from under-utilized and lower-emitting natural gas-fired units; in fact, this type of 're-dispatch' was invoked as one of the three building blocks used to set the emissions targets under the Environmental Protection Agency's Clean Power Plan. Despite the existence of surplus natural gas capacity in the U.S., power system operational constraints not often considered in power sector policy analyses, such as transmission congestion, generator ramping constraints, minimum generation constraints, planned and unplanned generator outages, and ancillary service requirements, could limit the potential and increase the cost of coal-to-gas re-dispatch. Using a highly detailed power system unit commitment and dispatch model, we estimate the maximum potential for re-dispatch in the Eastern Interconnection, which accounts for the majority of coal capacity and generation in the U.S. Under our reference assumptions, we find that maximizing coal-to-gas re-dispatch yields emissions reductions of 230 million metric tons (Mt), or 13% of power sector emissions in the Eastern Interconnection, with a corresponding average abatement cost of $15-$44 per metric ton of CO2, depending on the assumed supply elasticity of natural gas.

  11. Impacts of potential CO2-reduction policies on air quality in the United States.

    Science.gov (United States)

    Trail, Marcus A; Tsimpidi, Alexandra P; Liu, Peng; Tsigaridis, Kostas; Hu, Yongtao; Rudokas, Jason R; Miller, Paul J; Nenes, Athanasios; Russell, Armistead G

    2015-04-21

    Impacts of emissions changes from four potential U.S. CO2 emission reduction policies on 2050 air quality are analyzed using the community multiscale air quality model (CMAQ). Future meteorology was downscaled from the Goddard Institute for Space Studies (GISS) ModelE General Circulation Model (GCM) to the regional scale using the Weather Research Forecasting (WRF) model. We use emissions growth factors from the EPAUS9r MARKAL model to project emissions inventories for two climate tax scenarios, a combined transportation and energy scenario, a biomass energy scenario and a reference case. Implementation of a relatively aggressive carbon tax leads to improved PM2.5 air quality compared to the reference case as incentives increase for facilities to install flue-gas desulfurization (FGD) and carbon capture and sequestration (CCS) technologies. However, less capital is available to install NOX reduction technologies, resulting in an O3 increase. A policy aimed at reducing CO2 from the transportation sector and electricity production sectors leads to reduced emissions of mobile source NOX, thus reducing O3. Over most of the U.S., this scenario leads to reduced PM2.5 concentrations. However, increased primary PM2.5 emissions associated with fuel switching in the residential and industrial sectors leads to increased organic matter (OM) and PM2.5 in some cities.

  12. Potentials for energy saving and CO2 reduction in Baden-Wuerttemberg. Status report

    International Nuclear Information System (INIS)

    Weimer, W.; Luenstroth, U.

    1993-01-01

    In order to protect the climate the Administration of the state of Baden-Wuerttemberg aims at cutting energy-related CO 2 -emissions by 30% by the year 2005. This study analyses the potentials of energy consumption and CO 2 -reduction in the state of Baden-Wuerttemberg in the framework of an evaluation of literature. As special emphasis is put on technical steps such as an increase in efficiency with respect to the generation and consumption of energy as well as on the substitution of fossil energy sources by regenerative techniques of energy generation. In order to obtain considerable potentials of energy-saving a moderate increase in energy prices as well as several actions to reduce impediments are required . However, an achievement of those goals by the year 2005 is only partly possible, because of the time required. The evaluation of literature serves as a preparation of the comprehensive project Klimavertraegliche Energieversorgung in Baden-Wuerttemberg (greenhouse-gas-reduced energy supply in Baden-Wuerttemberg) of the Center of Technology Assessment in Baden-Wuerttemberg. (orig.) [de

  13. Technologies for utilization of industrial excess heat: Potentials for energy recovery and CO2 emission reduction

    International Nuclear Information System (INIS)

    Broberg Viklund, Sarah; Johansson, Maria T.

    2014-01-01

    Highlights: • Technologies for recovery and use of industrial excess heat were investigated. • Heat harvesting, heat storage, heat utilization, and heat conversion technologies. • Heat recovery potential for Gävleborg County in Sweden was calculated. • Effects on global CO 2 emissions were calculated for future energy market scenarios. - Abstract: Industrial excess heat is a large untapped resource, for which there is potential for external use, which would create benefits for industry and society. Use of excess heat can provide a way to reduce the use of primary energy and to contribute to global CO 2 mitigation. The aim of this paper is to present different measures for the recovery and utilization of industrial excess heat and to investigate how the development of the future energy market can affect which heat utilization measure would contribute the most to global CO 2 emissions mitigation. Excess heat recovery is put into a context by applying some of the excess heat recovery measures to the untapped excess heat potential in Gävleborg County in Sweden. Two different cases for excess heat recovery are studied: heat delivery to a district heating system and heat-driven electricity generation. To investigate the impact of excess heat recovery on global CO 2 emissions, six consistent future energy market scenarios were used. Approximately 0.8 TWh/year of industrial excess heat in Gävleborg County is not used today. The results show that with the proposed recovery measures approximately 91 GWh/year of district heating, or 25 GWh/year of electricity, could be supplied from this heat. Electricity generation would result in reduced global CO 2 emissions in all of the analyzed scenarios, while heat delivery to a DH system based on combined heat and power production from biomass would result in increased global CO 2 emissions when the CO 2 emission charge is low

  14. Energy saving and CO2-reduction potential of micro-cogeneration in the Netherlands (2010-2030). Update 2008

    International Nuclear Information System (INIS)

    Van Gastel, M.; De Jong, A.; Schlatmann, S.; Bakker, E.J.; Jeeninga, H.; Boerakker, Y.; Seebregts, A.; Menkveld, M.; Van Wolferen, H.; Turkstra, J.W.; Dam, J.; Harmsen, R.; Rooijers, F.; Koot, M.

    2008-05-01

    Various parties have been asked to come to a joint point of view with regard to establishing the potential of micro CHP for energy saving and CO2 emission reduction in the Netherlands from 2010 to 2030, assuming that micro CHP will have a successful market introduction. The result of this memo is a method for determining the technical potential of micro CHP for the reduction of energy use and CO2 emissions. This report is an update of the 2006 report [mk] [nl

  15. Assessment of CO2 emission reduction and identification of CDM potential in a township

    Energy Technology Data Exchange (ETDEWEB)

    Misra, R.; Aseri, Tarun Kumar; Jamuwa, Doraj Karnal [Department of Mechanical Engineering, Government Engineering College, Ajmer, Rajasthan (India); Bansal, V. [Department of Mechanical Engineering, Government Mahila Engineering College, Ajmer, Rajasthan (India)

    2012-11-15

    This paper presents the theoretical investigation of CDM opportunity in a township at Jaipur, India. The purpose of study is to identify and analyze the various opportunities viz., installation of solar water heater, energy efficient lighting, energy efficient air conditioners, and energy efficient submersible water pumps in desert coolers and thus achieve a considerable (65.7 %) reduction in GHG emissions. Out of the various opportunities considered, the retrofitting with solar water heater can be recommended for CDM. Though, the retrofitting with energy efficient lighting, energy efficient air conditioners and energy efficient submersible water pumps in desert coolers claimed CO2 emission reduction of 104.84, 25.92, and 36.94 tons per annum, respectively, but the only opportunity which got through CDM was retrofitting with solar water heater claiming 115.70 tCO2 (100 %) emission reductions per annum which could result into net earnings of 115.70 CERs. The simple and discounted payback period for all four project activities are also calculated with and without CDM and tax benefits.

  16. Charcoal injection in blast furnaces (Bio-PCI: CO2 reduction potential and economic prospects

    Directory of Open Access Journals (Sweden)

    Cristobal Feliciano-Bruzual

    2014-07-01

    Full Text Available The steel industry is under pressure to reduce its CO2 emissions, which arise from the use of coal. In the long-term, the injection of pulverized particles of charcoal from biomass through blast furnace tuyeres, in this case called Bio-PCI, is an attractive method from both an environmental and metallurgical viewpoint. The potential of Bio-PCI has been assessed in terms of its CO2 abatement potential and economic viewpoint. A cost objective function has been used to measure the impact of biochar substitution in highly fuel-efficient BF among the top nine hot metal producers; estimations are based on the relevant cost determinants of ironmaking. This contribution aims to shed light on two strategic questions: Under what conditions is the implementation of Bio-PCI economically attractive? Additionally, where is such a techno-economic innovation likely to be taken up the earliest? The results indicate the potential for an 18–40% mitigation of CO2. Findings from the economic assessment show that biochar cannot compete with fossil coal on price alone; therefore, a lower cost of biochar or the introduction of carbon taxes will be necessary to increase the competitiveness of Bio-PCI. Based on the current prices of raw materials, electricity and carbon taxes, biochar should be between 130.1 and 236.4 USD/t and carbon taxes should be between 47.1 and 198.7 USD/t CO2 to facilitate the substitution of Bio-PCI in the examined countries. In regard to implementation, Brazil, followed by India, China and the USA appeared to be in a better position to deploy Bio-PCI.

  17. Assessment of Energy Efficiency Improvement and CO2 Emission Reduction Potentials in India's Cement Industry

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, III, William R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Xu, Tengfang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-12-03

    India’s cement industry is the second largest in the world behind China with annual cement production of 168 Mt in 2010 which accounted for slightly greater than six percent of the world’s annual cement production in the same year. To produce that amount of cement, the industry consumed roughly 700 PJ of fuel and 14.7 TWh of electricity. We identified and analyzed 22 energy efficiency technologies and measures applicable to the processes in the Indian cement industry. The Conservation Supply Curve (CSC) used in this study is an analytical tool that captures both the engineering and the economic perspectives of energy conservation. Using a bottom-up electricity CSC model and compared to an electricity price forecast the cumulative cost-effective plant-level electricity savings potential for the Indian cement industry for 2010- 2030 is estimated to be 83 TWh, and the cumulative plant-level technical electricity saving potential is 89 TWh during the same period. The grid-level CO2 emissions reduction associated with cost-effective electricity savings is 82 Mt CO2 and the electric grid-level CO2 emission reduction associated with technical electricity saving potential is 88 Mt CO2. Compared to a fuel price forecast, an estimated cumulative cost-effective fuel savings potential of 1,029 PJ with associated CO2 emission reduction of 97 Mt CO2 during 2010-2030 is possible. In addition, a sensitivity analysis with respect to the discount rate used is conducted to assess the effect of changes in this parameter on the results. The result of this study gives a comprehensive and easy to understand perspective to the Indian cement industry and policy makers about the energy efficiency potential and its associated cost over the next twenty years.

  18. CO2 reduction by dematerialization

    Energy Technology Data Exchange (ETDEWEB)

    Hekkert, M.P. [Department of Innovation Studies, Copernicus Institute, Utrecht University, Utrecht (Netherlands)

    2002-04-01

    Current policy for the reduction of greenhouse gases is mainly concerned with a number of types of solutions: energy saving, shifting to the use of low-carbon fuels and the implementation of sustainable energy technologies. Recent research has shown that a strategy directed at a more efficient use of materials could make a considerable contribution to reducing CO2 emissions. Moreover, the costs to society as a whole of such a measure appear to be very low.

  19. CO2 reduction potential of future coal gasification based power generation technologies

    International Nuclear Information System (INIS)

    Jansen, D.; Oudhuis, A.B.J.; Van Veen, H.M.

    1992-03-01

    Assessment studies are carried out on coal gasification power plants integrated with gas turbines (IGCC) or molten carbonate fuel cells (MCFC) without and with CO 2 -removal. System elements include coal gasification, high-temperature gas-cleaning, molten carbonate fuel cells or gas turbines, CO shift, membrane separation, CO 2 recovery and a bottoming cycle. Various system configurations are evaluated on the basis of thermodynamic computations. The energy balances of the various system configurations clearly indicate that integrated coal gasification MCFC power plants (IGMCFC) with CO 2 removal have high efficiencies (42-47% LHV) compared to IGCC power plants with CO 2 -removal (33-38% LHV) and that the CO 2 -removal is simplified due to the specific properties of the molten carbonate fuel cells. IGMCFC is therefore an option with future prospective in the light of clean coal technologies for power generation with high energy efficiencies and low emissions. 2 figs., 3 tabs., 10 refs

  20. Potential vehicle fleet CO2 reductions and cost implications for various vehicle technology deployment scenarios in Europe

    International Nuclear Information System (INIS)

    Pasaoglu, Guzay; Honselaar, Michel; Thiel, Christian

    2012-01-01

    The continuous rise in demand for road transportation has a significant effect on Europe's oil dependency and emissions of greenhouse gases. Alternative fuels and vehicle technology can mitigate these effects. This study analyses power-train deployment scenarios for passenger cars and light commercial vehicles in EU-27 until 2050. It considers European policy developments on vehicle CO 2 emissions, bio-energy mandates and reductions in the CO 2 footprint of the European energy mix and translates these into comprehensive scenarios for the road transport sector. It quantifies and assesses the potential impact of these scenarios on well-to-wheel (WtW) CO 2 emission reductions primary energy demand evolution, and cost aspects for the prospective vehicle owners. The study reveals that, under the deployed scenarios, the use of bio-fuel blends, technological learning and the deployment of hybrids, battery electric, plug-in hybrid and fuel cell vehicles can decrease WtW CO 2 emissions in EU-27 passenger road transport by 35–57% (compared to 2010 levels) and primary energy demand by 29–51 Mtoe as they would benefit from a future assumed decarbonised electricity and hydrogen mix in Europe. Learning effects can lead to acceptable payback periods for vehicle owners of electric drive vehicles. - Highlights: ► Power-train penetration scenarios for 2010–2050 passenger road transport in Europe. ► A dedicated tool is developed to analyse H 2 production and distribution mix till 2050. ► Alternative vehicles can drastically reduce CO 2 emissions and energy demand. ► Electric vehicles could become cost competitive to conventional vehicles by 2030. ► Policies needed to create adequate momentum and guarantee decarbonised transport.

  1. Efficiency potentials of heat pumps with combined heat and power. For maximum reduction of CO2 emissions and for electricity generation from fossil fuels with CO2 reduction in Switzerland

    International Nuclear Information System (INIS)

    Rognon, F.

    2005-06-01

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) takes a look at how the efficiency potential of heat pumps together with combined heat and power systems can help provide a maximum reduction of CO 2 emissions and provide electricity generation from fossil fuel in Switzerland together with reductions in CO 2 emissions. In Switzerland, approximately 80% of the low-temperature heat required for space-heating and for the heating-up of hot water is produced by burning combustibles. Around a million gas and oil boilers were in use in Switzerland in 2000, and these accounted for approximately half the country's 41.1 million tonnes of CO 2 emissions. The authors state that there is a more efficient solution with lower CO 2 emissions: the heat pump. With the enormous potential of our environment it would be possible to replace half the total number of boilers in use today with heat pumps. This would be equivalent to 90 PJ p.a. of useful heat, or 500,000 systems. The power source for heat pumps should come from the substitution of electric heating systems (electric resistor-based systems) and from the replacement of boilers. This should be done by using combined heat and power systems with full heat utilisation. This means, according to the authors, that the entire required power source can be provided without the need to construct new electricity production plants. The paper examines and discusses the theoretical, technical, market and realisable potentials

  2. Combining IPPC and emission trading: An assessment of energy efficiency and CO2 reduction potentials in the Austrian paper industry

    International Nuclear Information System (INIS)

    Starzer, Otto; Dworak, Oliver

    2005-01-01

    In the frame of an innovative project partnership E.V.A. - the Austrian Energy Agency accompanied the Austrian paper industry for the last 2.5 years in developing a branch specific climate change strategy. Within the scope of this project an assessment of the energy efficiency status of the branch was carried out as well as an evaluation of still realisable energy savings and CO 2 reduction potentials. The paper presents the methodology applied, which combines a top down approach (benchmarking and best practice) with a bottom up approach (on-site interviews and energy audits), supported by a huge data collection process. Within the benchmarking process all Austrian paper industry installations affected by the EU emission trading directive were benchmarked against their respective IPPC/BAT values. Furthermore an extensive list of best practice examples derived from existing or ongoing studies was compared with the energy efficiency measures already carried out by the companies ('early actions'). These theory-oriented findings were complemented by several on-site interviews with the respective energy managers as well as by detailed energy audits carried out by a consulting company, covering in total more than 80% of the Austrian paper industry's CO 2 emissions. The paper concludes with the main results of the project, presenting the pros and cons of working with IPPC documents and BAT values in terms of energy efficiency assessments. Recommendations are presented on how to improve the allocation exercise for the next emission trading period from 2008 to 2012

  3. Estimating CO2 Emission Reduction of Non-capture CO2 Utilization (NCCU) Technology

    International Nuclear Information System (INIS)

    Lee, Ji Hyun; Lee, Dong Woog; Gyu, Jang Se; Kwak, No-Sang; Lee, In Young; Jang, Kyung Ryoung; Shim, Jae-Goo; Choi, Jong Shin

    2015-01-01

    Estimating potential of CO 2 emission reduction of non-capture CO 2 utilization (NCCU) technology was evaluated. NCCU is sodium bicarbonate production technology through the carbonation reaction of CO 2 contained in the flue gas. For the estimating the CO 2 emission reduction, process simulation using process simulator (PRO/II) based on a chemical plant which could handle CO 2 of 100 tons per day was performed, Also for the estimation of the indirect CO 2 reduction, the solvay process which is a conventional technology for the production of sodium carbonate/sodium bicarbonate, was studied. The results of the analysis showed that in case of the solvay process, overall CO 2 emission was estimated as 48,862 ton per year based on the energy consumption for the production of NaHCO 3 (7.4 GJ/tNaHCO 3 ). While for the NCCU technology, the direct CO 2 reduction through the CO 2 carbonation was estimated as 36,500 ton per year and the indirect CO 2 reduction through the lower energy consumption was 46,885 ton per year which lead to 83,385 ton per year in total. From these results, it could be concluded that sodium bicarbonate production technology through the carbonation reaction of CO 2 contained in the flue was energy efficient and could be one of the promising technology for the low CO 2 emission technology.

  4. Geothermal energy of Slovakia - CO2 emissions reduction contribution potential (background study for conservative and non-conservative approach

    Directory of Open Access Journals (Sweden)

    Branislav Fričovský

    2012-12-01

    Full Text Available Total geothermal energy potential is estimated for 209 714 TJ per year or 6 650 MWth. Natural conditions define a use of thermalwaters for heat generation only. Accepting proportion of real achievable output of geothermal projects in the non-conservative scenarioat a rate of 1 861 MWth or 13 440 TJ per year, yearly carbon dioxide savings are up to reach 0,357 MtCO2.yr-1 or 12,5 of cumulativeMtCO2 in 35 years. By a contrast, introduction of conservative approach points to increase in a geothermal heat production from 145 to243 TJ per period or 6 944 TJ of cumulative 35 years production, with a real outcome of 0,45 MtCO2 cumulative carbon dioxidesavings, corresponding to yearly real savings from 9,4 .10-3 to 15,8 .10-3 MtCO2.

  5. Scenario analysis of energy saving and CO_2 emissions reduction potentials to ratchet up Japanese mitigation target in 2030 in the residential sector

    International Nuclear Information System (INIS)

    Wakiyama, Takako; Kuramochi, Takeshi

    2017-01-01

    This paper assesses to what extent CO_2 emissions from electricity in the residential sector can be further reduced in Japan beyond its post-2020 mitigation target (known as “Intended Nationally Determined Contribution (INDC)”). The paper examines the reduction potential of electricity demand and CO_2 emissions in the residential sector by conducting a scenario analysis. Electricity consumption scenarios are set up using a time-series regression model, and used to forecast the electricity consumption patterns to 2030. The scenario analysis also includes scenarios that reduce electricity consumption through enhanced energy efficiency and energy saving measures. The obtained results show that Japan can reduce electricity consumption and CO_2 emissions in the residential sector in 2030 more than the Japanese post-2020 mitigation target indicates. At the maximum, the electricity consumption could be reduced by 35 TWh, which contributes to 55.4 MtCO_2 of emissions reduction in 2030 compared to 2013 if the voluntarily targeted CO_2 intensity of electricity is achieved. The result implies that Japan has the potential to ratchet up post-2020 mitigation targets discussed under the Paris Agreement of the United Nations Framework Convention on Climate Change (UNFCCC). - Highlights: • Further reduction of electricity consumption is possible beyond Japan's post-2020 mitigation target. • Energy saving efforts by households and incentives to reduce electricity demands are required. • Improvement of CO_2 intensity from electricity is a key factor in the reduction of CO_2 emissions.

  6. CO2 reduction through energy conservation

    International Nuclear Information System (INIS)

    1991-05-01

    A study was carried out of the potential to economically reduce carbon dioxide emissions through energy conservation in the petroleum and natural gas industry. The study examined current and projected emissions levels, cogeneration at gas plants, flaring, economics, regulation, reporting requirements, implementation, and research and development. Economically attractive energy conservation measures can reduce oil and gas industry, exclusive of Athabasca oil sands operations, CO 2 emissions by 6-7%. The energy conservation options identified range from field energy awareness committees through to equipment retrofits and replacement. At ca 3 million tonnes/y, these reductions will not offset the increases in oil and gas related CO 2 emissions anticipated by producers and Alberta government agencies. There will be increasing emphasis on in-situ bitumen production, more energy intensive light crude oil production and increasing natural gas sales, increasing energy inputs in excess of reductions. Cogeneration of electricity for utility company distribution and for internally required steam at gas plants and in-situ production sites is not economic due to low electricity prices. 8 tabs

  7. Electrocatalytic Alloys for CO2 Reduction.

    Science.gov (United States)

    He, Jingfu; Johnson, Noah J J; Huang, Aoxue; Berlinguette, Curtis P

    2018-01-10

    Electrochemically reducing CO 2 using renewable energy is a contemporary global challenge that will only be met with electrocatalysts capable of efficiently converting CO 2 into fuels and chemicals with high selectivity. Although many different metals and morphologies have been tested for CO 2 electrocatalysis over the last several decades, relatively limited attention has been committed to the study of alloys for this application. Alloying is a promising method to tailor the geometric and electric environments of active sites. The parameter space for discovering new alloys for CO 2 electrocatalysis is particularly large because of the myriad products that can be formed during CO 2 reduction. In this Minireview, mixed-metal electrocatalyst compositions that have been evaluated for CO 2 reduction are summarized. A distillation of the structure-property relationships gleaned from this survey are intended to help in the construction of guidelines for discovering new classes of alloys for the CO 2 reduction reaction. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. PLAINS CO2 REDUCTION (PCOR) PARTNERSHIP

    Energy Technology Data Exchange (ETDEWEB)

    Edward N. Steadman; Daniel J. Daly; Lynette L. de Silva; John A. Harju; Melanie D. Jensen; Erin M. O' Leary; Wesley D. Peck; Steven A. Smith; James A. Sorensen

    2006-01-01

    During the period of October 1, 2003, through September 30, 2005, the Plains CO2 Reduction (PCOR) Partnership, identified geologic and terrestrial candidates for near-term practical and environmentally sound carbon dioxide (CO2) sequestration demonstrations in the heartland of North America. The PCOR Partnership region covered nine states and three Canadian provinces. The validation test candidates were further vetted to ensure that they represented projects with (1) commercial potential and (2) a mix that would support future projects both dependent and independent of CO2 monetization. This report uses the findings contained in the PCOR Partnership's two dozen topical reports and half-dozen fact sheets as well as the capabilities of its geographic information system-based Decision Support System to provide a concise picture of the sequestration potential for both terrestrial and geologic sequestration in the PCOR Partnership region based on assessments of sources, sinks, regulations, deployment issues, transportation, and capture and separation. The report also includes concise action plans for deployment and public education and outreach as well as a brief overview of the structure, development, and capabilities of the PCOR Partnership. The PCOR Partnership is one of seven regional partnerships under Phase I of the U.S. Department of Energy National Energy Technology Laboratory's Regional Carbon Sequestration Partnership program. The PCOR Partnership, comprising 49 public and private sector members, is led by the Energy & Environmental Research Center at the University of North Dakota. The international PCOR Partnership region includes the Canadian provinces of Alberta, Saskatchewan, and Manitoba and the states of Montana (part), Wyoming (part), North Dakota, South Dakota, Nebraska, Missouri, Iowa, Minnesota, and Wisconsin.

  9. Fiscal 1996 survey of potential international cooperation for a long-term scenario on CO2 reduction; 1996 nendo CO2 sakugen ni kakawaru choki shinario ni kansuru kokusai kyoryoku kanosei chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    For the purpose of working out a CO2 reduction scenario and a CO2 policy introduction scenario, a survey was conducted of comparisons between ten and several models which are world-known and models of the New Earth 21, potential international cooperation to be carried out in the future, etc. The survey included organizations which are developing CO2 policy evaluation models, survey reports made in the past, details of literature for the analysis and arrangement. From the result, details of the questionnaire survey and organizations to be surveyed were decided on for the questionnaire survey. Objects for the survey were 7 countries and 22 organizations, and survey items were places for information exchange, sending/receiving of researchers, exchange of input data, comparative calculation based on the common database, joint research work, economy, the carbon tax, impact, renewable energy, how to handle and think of the carbon isolation, etc. As a result of the survey, proposed were a workshop on CO2 reduction, a comparative study of simulation models, etc. 25 refs., 50 figs., 12 tabs.

  10. Least cost planning for CO2-reduction strategies

    International Nuclear Information System (INIS)

    Seifritz, W.

    1990-01-01

    A first recommendation for the determination of the minimum costs for a carbon-dioxide reduction strategy is presented. For this, the tabulation of so-called, 'CO 2 -ranking-lists', containing the relationship between the costs of a distinct measure to avoid the emission of certain amount of CO 2 (in dollar/t CO 2 ) versus its potential (in t CO 2 /yr), is indispensable. Some basic aspects of this approach are discussed and a first guess of the costs of some measures to avoid CO 2 -emissions into the atmosphere is presented. (orig.) [de

  11. Potential reduction of CO2 emissions and low carbon scenario for the Brazilian industrial sector for 2030; Potencial de reducao de emissoes de Co2 e cenario de baixo carbono para o setor industrial brasileiro para 2030

    Energy Technology Data Exchange (ETDEWEB)

    Henriques Junior, Mauricio F. [Instituto Nacional de Tecnologia (INT), Rio de Janeiro, RJ (Brazil)], email: mauricio.henriques@int.gov.br; Schaeffer, Roberto [Coordenacao dos Programas de Pos-Graduacao de Engenharia (COPPE/UFRJ), RJ (Brazil)], email: roberto@ppe.ufrj.br

    2010-07-01

    This study discusses the potential for reducing carbon dioxide (CO2) emissions from energy use by the Brazilian industrial sector in a low-carbon scenario over a horizon until 2030. It evaluates the main mitigation measures, the quantities of this gas avoided and the respective abatement costs. In relation to a benchmark scenario projected for 2030, the reduction of CO2 emissions estimated here can reach 40% by adopting energy efficiency measures, materials recycling, cogeneration, shifting from fossil fuels to renewable or less carbon content sources, and eliminating the use of biomass from deforestation. The set of measures studied here would bring cumulative emissions reductions of nearly 1.5 billion tCO2 over a period of 20 years (2010-2030). This would require huge investments, but the majority of them would have significant economic return and negative abatement costs. However, in the cases there would be low economic attractiveness and higher abatement costs, thus requiring more effective incentives and a collective effort, from both the public and private sectors. (author)

  12. Economic efficiency of CO2 reduction programs

    International Nuclear Information System (INIS)

    Tahvonen, O.; Storch, H. von; Storch, J. von

    1993-01-01

    A highly simplified time-dependent low-dimensional system has been designed to describe conceptually the interaction of climate and economy. Enhanced emission of carbon dioxide (CO 2 ) is understood as the agent that not only favors instantaneous consumption but also causes unfavorable climate changes at a later time. The problem of balancing these two counterproductive effects of CO 2 emissions on a finite time horizon is considered. The climate system is represented by just two parameters, namely a globally averaged near-surface air-temperature and a globally averaged troposheric CO 2 concentration. The costs of abating CO 2 emissions are monitored by a function which depends quadratically on the percentage reduction of emission compared to an 'uncontrolled emission' scenario. Parameters are fitted to historical climate data and to estimates from studies of CO 2 abatement costs. Two optimization approaches, which differ from earlier attempts to describe the interaction of economy and climate, are discussed. In the 'cost oriented' strategy an optimal emission path is identified which balances the abatement costs and explicitly formulated damage costs. These damage costs, whose estimates are very uncertain, are hypothesized to be a linear function of the time-derivative of temperature. In the 'target oriented' strategy an emission path is chosen so that the abatement costs are minimal while certain restrictions on the terminal temperature and concentration change are met. (orig.)

  13. Tuning of CO2 Reduction Selectivity on Metal Electrocatalysts.

    Science.gov (United States)

    Wang, Yuhang; Liu, Junlang; Wang, Yifei; Al-Enizi, Abdullah M; Zheng, Gengfeng

    2017-11-01

    Climate change, caused by heavy CO 2 emissions, is driving new demands to alleviate the rising concentration of atmospheric CO 2 levels. Enlightened by the photosynthesis of green plants, photo(electro)chemical catalysis of CO 2 reduction, also known as artificial photosynthesis, is emerged as a promising candidate to address these demands and is widely investigated during the past decade. Among various artificial photosynthetic systems, solar-driven electrochemical CO 2 reduction is widely recognized to possess high efficiencies and potentials for practical application. The efficient and selective electroreduction of CO 2 is the key to the overall solar-to-chemical efficiency of artificial photosynthesis. Recent studies show that various metallic materials possess the capability to play as electrocatalysts for CO 2 reduction. In order to achieve high selectivity for CO 2 reduction products, various efforts are made including studies on electrolytes, crystal facets, oxide-derived catalysts, electronic and geometric structures, nanostructures, and mesoscale phenomena. In this Review, these methods for tuning the selectivity of CO 2 electrochemical reduction of metallic catalysts are summarized. The challenges and perspectives in this field are also discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. CuZn Alloy- Based Electrocatalyst for CO2 Reduction

    KAUST Repository

    Alazmi, Amira

    2014-06-01

    ABSTRACT CuZn Alloy- Based Electrocatalyst for CO2 Reduction Amira Alazmi Carbon dioxide (CO2) is one of the major greenhouse gases and its emission is a significant threat to global economy and sustainability. Efficient CO2 conversion leads to utilization of CO2 as a carbon feedstock, but activating the most stable carbon-based molecule, CO2, is a challenging task. Electrochemical conversion of CO2 is considered to be the beneficial approach to generate carbon-containing fuels directly from CO2, especially when the electronic energy is derived from renewable energies, such as solar, wind, geo-thermal and tidal. To achieve this goal, the development of an efficient electrocatalyst for CO2 reduction is essential. In this thesis, studies on CuZn alloys with heat treatments at different temperatures have been evaluated as electrocatalysts for CO2 reduction. It was found that the catalytic activity of these electrodes was strongly dependent on the thermal oxidation temperature before their use for electrochemical measurements. The polycrystalline CuZn electrode without thermal treatment shows the Faradaic efficiency for CO formation of only 30% at applied potential ~−1.0 V vs. RHE with current density of ~−2.55 mA cm−2. In contrast, the reduction of oxide-based CuZn alloy electrode exhibits 65% Faradaic efficiency for CO at lower applied potential about −1.0 V vs. RHE with current density of −2.55 mA cm−2. Furthermore, stable activity was achieved over several hours of the reduction reaction at the modified electrodes. Based on electrokinetic studies, this improvement could be attributed to further stabilization of the CO2•− on the oxide-based Cu-Zn alloy surface.

  15. Potential for energy conservation and reduction of CO2 emissions in the Brazilian cement industry through 2015

    International Nuclear Information System (INIS)

    Soares, J.B.; Tolmasquim, M.T.

    1999-01-01

    The cement industry is characterized by intensive energy consumption throughout its production stages which, together with the calcination of its raw materials, accounts for significant amounts of greenhouse gases (GHG) emissions. In 1996, the Brazilian cement industry consumed 4.3% of the energy required by the industrial sector, contributing over 22 Mtons (Million of tons) of CO 2 . The prospects for growth in this sector in Brazil indicate rising demands for fossil fuels, with a consequent upsurge in emissions. The purpose of this article is to present the prospects for energy conservation in the Brazilian cement industry through to 2015, taking into account the introduction of new production technologies in this sector, the use of waste and low-grade fuels, cogeneration, the use of additives, and other measures, based on a technical and economic energy demand simulation model

  16. Smart Transportation CO2 Emission Reduction Strategies

    Science.gov (United States)

    Tarulescu, S.; Tarulescu, R.; Soica, A.; Leahu, C. I.

    2017-10-01

    Transport represents the sector with the fastest growing greenhouse gas emissions around the world. The main global objective is to reduce energy usage and associated greenhouse gas emissions from the transportation sector. For this study it was analyzed the road transportation system from Brasov Metropolitan area. The study was made for the transportation route that connects Ghimbav city to the main surrounding objectives. In this study ware considered four optimization measures: vehicle fleet renewal; building the detour belt for the city; road increasing the average travel speed; making bicycle lanes; and implementing an urban public transport system for Ghimbav. For each measure it was used a mathematical model to calculate the energy consumption and carbon emissions from the road transportation sector. After all four measures was analyzed is calculated the general energy consumption and CO2 reduction if this are applied from year 2017 to 2020.

  17. Advances in Photocatalytic CO2 Reduction with Water: A Review

    Directory of Open Access Journals (Sweden)

    Samsun Nahar

    2017-06-01

    Full Text Available In recent years, the increasing level of CO2 in the atmosphere has not only contributed to global warming but has also triggered considerable interest in photocatalytic reduction of CO2. The reduction of CO2 with H2O using sunlight is an innovative way to solve the current growing environmental challenges. This paper reviews the basic principles of photocatalysis and photocatalytic CO2 reduction, discusses the measures of the photocatalytic efficiency and summarizes current advances in the exploration of this technology using different types of semiconductor photocatalysts, such as TiO2 and modified TiO2, layered-perovskite Ag/ALa4Ti4O15 (A = Ca, Ba, Sr, ferroelectric LiNbO3, and plasmonic photocatalysts. Visible light harvesting, novel plasmonic photocatalysts offer potential solutions for some of the main drawbacks in this reduction process. Effective plasmonic photocatalysts that have shown reduction activities towards CO2 with H2O are highlighted here. Although this technology is still at an embryonic stage, further studies with standard theoretical and comprehensive format are suggested to develop photocatalysts with high production rates and selectivity. Based on the collected results, the immense prospects and opportunities that exist in this technique are also reviewed here.

  18. CO2 Emission Reduction in Energy Sector

    International Nuclear Information System (INIS)

    Bole, A.; Sustersic, A.; Voncina, R.

    2013-01-01

    Due to human activities, concentrations of the greenhouse gases increase in the atmosphere much quicker than they naturally would. Today it is clear that climate change is the result of human activities. With the purpose of preventing, reducing and mitigating of climate change, the EU, whose member is also Slovenia, set ambitious goals. In order to keep rise of the global atmosphere temperature below 2 degrees of C, the European Council set an objective of reducing greenhouse gas emissions by 80 - 95 % by 2050 compared to 1990. It is important that every single individual is included in achieving of these goals. Certainly, the most important role is assumed by individual sectors especially Public Electricity and Heat Production sector as one of the greatest emitters of the greenhouse gases. As a possible solution of radical reduction of the greenhouse gases emission from mentioned sector Carbon Capture and Storage (CCS) technology is implemented. In the article the range of CO 2 reduction possibilities, technology demands and environmental side effects of CCS technology are described. Evaluation of CCS implementation possibilities in Slovenia is also included.(author)

  19. Simulating the potential for Carbon Dioxide (CO2) reduction by the application of environmentally friendly transportation (case study: Gatot Subroto Street, Medan City)

    Science.gov (United States)

    Suryati, Isra; Turmuzi Lubis, Muhammad; Mawaddah, Nurul

    2018-03-01

    Carbon Dioxide (CO2) is one of the greenhouse gases. One source of greenhouse gases comes from the use of fossil fuels from the transport sector. The transportation sector is one of the dominant sectors in contributing to the greenhouse effect. This study aims to calculate the amount of CO2 from transportation activities by using mobile six equations in Gatot Subroto Street, Medan City. A sampling of CO2 concentration was done using Carbon Dioxide Monitor with Non-Dispersive Infra Red (NDIR) Analyzer method. Also, a simulation of the reduction of the number of private vehicles to mass transportation such as BRT gas-fired. The results showed CO2 emissions calculations with mobile six ranged from 47.2 kg CO2 - 978.2 kg CO2. Meanwhile, measurements range from 3,004 ppm - 3,405 ppm. Implementation of the concept of environmentally friendly transportation such as BRT in Gatot Subroto Street, Medan City will be able to reduce the average emissions load CO2 by 42.75% -78.80%. Based on the calculation simulation in this study is estimated the number of BRT required approximately 71 units.

  20. Achieving CO2 Emissions Reduction Goals with Energy Infrastructure Projects

    International Nuclear Information System (INIS)

    Eberlinc, M.; Medved, K.; Simic, J.

    2013-01-01

    The EU has set its short-term goals in the Europe 2020 Strategy (20% of CO 2 emissions reduction, 20% increase in energy efficiency, 20% share of renewables in final energy). The analyses show that the EU Member States in general are on the right track of achieving these goals; they are even ahead (including Slovenia). But setting long-term goals by 2050 is a tougher challenge. Achieving CO 2 emissions reduction goes hand in hand with increasing the share of renewables and strategically planning the projects, which include exploiting the potential of renewable sources of energy (e.g. hydropower). In Slovenia, the expected share of hydropower in electricity production from large HPPs in the share of renewables by 2030 is 1/3. The paper includes a presentation of a hydro power plants project on the middle Sava river in Slovenia and its specifics (influenced by the expansion of the Natura 2000 protected sites and on the other hand by the changes in the Environment Protection Law, which implements the EU Industrial Emissions Directive and the ETS Directive). Studies show the importance of the HPPs in terms of CO 2 emissions reduction. The main conclusion of the paper shows the importance of energy infrastructure projects, which contribute to on the one hand the CO 2 emissions reduction and on the other the increase of renewables.(author)

  1. Potential of plug-in hybrid electric vehicle for reduction of CO2 emission and role of non-fossil power plant

    International Nuclear Information System (INIS)

    Hiwatari, R.; Okano, K.; Yamamoto, H.

    2009-01-01

    A method to analyze the demand of electricity and the reduction of CO 2 emission and oil consumption by PHEV is established. Using the performance of PHEV optimized by EPRI and an estimation on the pattern of driving and charging in Japan, the following results are obtained. The electric demand for PHEV60(which has 60mile EV range) and PHEV20(which has 20mile EV range) is evaluated at 79.3 billion kWh and 41.2 billion kWh, respectively, in case that all vehicles in Japan (80 million cars) would be replaced by PHEV. The load leveling effect on the Japanese grid, which is hypothetically considered as one electric grid system, is evaluated at about 30 million kW, in case that all vehicles in Japan are replaced by PHEV60 and charged in the midnight. However, when the charge of PHEVs starts in the evening, that effect is not obtained. The reduction of CO 2 emission results in 64 million ton by the averaged CO 2 emissions intensity (emissions per unit of user end electricity) in Japan, and 98 million ton by electricity from the non-fossil power plant such as nuclear energy or renewable one. Those values are equivalent to 25% and 38% of CO 2 emission from the transport sector in Japan in 2003. Hence, non-fossil power plant enhances the reduction of CO 2 emission by the PHEV introduction. (author)

  2. Short-rotation forestry of birch, maple, poplar and willow in Flanders (Belgium) II. Energy production and CO2 emission reduction potential

    International Nuclear Information System (INIS)

    Walle, Inge van de; Camp, Nancy van; Casteele, Liesbet van de; Verheyen, Kris; Lemeur, Raoul

    2007-01-01

    Belgium, being an EU country, has committed itself to a 7.5% reduction of greenhouse gas emissions during the first commitment period of the Kyoto Protocol. Within this framework, the Flemish government aims at reaching a share of 6% of renewable electricity in the total electricity production by 2010. In this work, the biomass production of birch, maple, poplar and willow in a short-rotation forestry (SRF) plantation after a 4-year growth period served as the base to calculate the amount of (electrical) energy that could be produced by this type of bioenergy crop in Flanders. The maximum amount of electricity that could be provided by SRF biomass was estimated at 72.9 GWh e year -1 , which only accounts for 0.16% of the total electricity production in this region. Although the energy output was rather low, the bioenergy production process under consideration appeared to be more energy efficient than energy production processes based on fossil fuels. The high efficiency of birch compared to the other species was mainly due to the high calorific value of the birch wood. The maximum CO 2 emission reduction potential of SRF plantations in Flanders was estimated at only 0.09% of the total annual CO 2 emission. The most interesting application of SRF in Flanders seemed to be the establishment of small-scale plantations, linked to a local combined heat and power plant. These plantations could be established on marginal arable soils or on polluted sites, and they could be of importance in the densely populated area of Flanders because of other environmental benefits, among which their function as (temporary) habitat for many species

  3. Climate change and CO2 emission reductions

    International Nuclear Information System (INIS)

    Ha Duong, M.; Campos, A.S.

    2007-04-01

    This paper presents the results of an opinion poll performed on a representative sample of 1000 persons about their sensitivity to climate change and to environment protection, their knowledge about technologies which are useful for environment protection, their opinion about geological CO 2 sequestration, and technologies to be developed to struggle against climate warming

  4. CO2 reduction strategies for the Northern Netherlands

    NARCIS (Netherlands)

    Benders, Rene; Moll, Henk; Noorman, Klaas Jan; Wiersma, Gerwin

    2011-01-01

    The concern about global warming initiated ambitious CO2 reduction goals in cities and regions in the Netherlands. This article describes a study of such a local initiative for the Northern Netherlands. The research aimed to develop CO2 reduction scenarios for 2035 with national and international

  5. Uncertainty quantification of CO2 emission reduction for maritime shipping

    International Nuclear Information System (INIS)

    Yuan, Jun; Ng, Szu Hui; Sou, Weng Sut

    2016-01-01

    The International Maritime Organization (IMO) has recently proposed several operational and technical measures to improve shipping efficiency and reduce the greenhouse gases (GHG) emissions. The abatement potentials estimated for these measures have been further used by many organizations to project future GHG emission reductions and plot Marginal Abatement Cost Curves (MACC). However, the abatement potentials estimated for many of these measures can be highly uncertain as many of these measures are new, with limited sea trial information. Furthermore, the abatements obtained are highly dependent on ocean conditions, trading routes and sailing patterns. When the estimated abatement potentials are used for projections, these ‘input’ uncertainties are often not clearly displayed or accounted for, which can lead to overly optimistic or pessimistic outlooks. In this paper, we propose a methodology to systematically quantify and account for these input uncertainties on the overall abatement potential forecasts. We further propose improvements to MACCs to better reflect the uncertainties in marginal abatement costs and total emissions. This approach provides a fuller and more accurate picture of abatement forecasts and potential reductions achievable, and will be useful to policy makers and decision makers in the shipping industry to better assess the cost effective measures for CO 2 emission reduction. - Highlights: • We propose a systematic method to quantify uncertainty in emission reduction. • Marginal abatement cost curves are improved to better reflect the uncertainties. • Percentage reduction probability is given to determine emission reduction target. • The methodology is applied to a case study on maritime shipping.

  6. Reduction of CO2 emissions by influencing fuel prices

    International Nuclear Information System (INIS)

    Keller, M.; Zbinden, R.; Haan, P.; Gruetter, J.; Ott, W.

    2002-01-01

    viable option. If, however, the more sensible - as far as ecological issues and CO 2 are concerned - use of biogas is not to be hindered, biogas' handicap must be taken into account when promotional measures are planned (e.g. graduated tax-exemption, delivery agreements). For bio-fuels, the addition of ethanol to petrol (E10: 10% added) seems to be a viable option with significant CO 2 emission reduction potential at comparatively low costs, but not the addition of 85% (E85) because of vehicle modification costs and costs for the additional infrastructure, or the promotion of RME (Rapeseed-Methyl-Ester) because of very high CO 2 emission avoidance costs and negative local environmental effects

  7. Catholyte-Free Electrocatalytic CO2 Reduction to Formate.

    Science.gov (United States)

    Lee, Wonhee; Kim, Young Eun; Youn, Min Hye; Jeong, Soon Kwan; Park, Ki Tae

    2018-04-16

    Electrochemical reduction of carbon dioxide (CO 2 ) into value-added chemicals is a promising strategy to reduce CO 2 emission and mitigate climate change. One of the most serious problems in electrocatalytic CO 2 reduction (CO 2 R) is the low solubility of CO 2 in an aqueous electrolyte, which significantly limits the cathodic reaction rate. This paper proposes a facile method of catholyte-free electrocatalytic CO 2 reduction to avoid the solubility limitation using commercial tin nanoparticles as a cathode catalyst. Interestingly, as the reaction temperature rises from 303 K to 363 K, the partial current density (PCD) of formate improves more than two times with 52.9 mA cm -2 , despite the decrease in CO 2 solubility. Furthermore, a significantly high formate concentration of 41.5 g L -1 is obtained as a one-path product at 343 K with high PCD (51.7 mA cm -2 ) and high Faradaic efficiency (93.3 %) via continuous operation in a full flow cell at a low cell voltage of 2.2 V. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Analysis of CO2 emissions reduction in the Malaysian transportation sector: An optimisation approach

    International Nuclear Information System (INIS)

    Mustapa, Siti Indati; Bekhet, Hussain Ali

    2016-01-01

    The demand for transport services is expected to rise, causing the CO 2 emissions level to increase as well. In Malaysia, the transportation sector accounts for 28% of total CO 2 emissions, of which 85% comes from road transport. By 2020, Malaysia is targeting a reduction in CO 2 emissions intensity by up to 40% and in this effort the role of road transport is paramount. This paper attempts to investigate effective policy options that can assist Malaysia in reducing the CO 2 emissions level. An Optimisation model is developed to estimate the potential CO 2 emissions mitigation strategies for road transport by minimising the CO 2 emissions under the constraint of fuel cost and demand travel. Several mitigation strategies have been applied to analyse the effect of CO 2 emissions reduction potential. The results demonstrate that removal of fuel price subsidies can result in reductions of up to 652 ktonnes of fuel consumption and CO 2 emissions can be decreased by 6.55%, which would enable Malaysia to hit its target by 2020. CO 2 emissions can be reduced significantly, up to 20%, by employing a combination of mitigation policies in Malaysia. This suggests that appropriate mitigation policies can assist the country in its quest to achieve the CO 2 emissions reduction target. - Highlights: • An optimisation model for CO 2 emissions reduction in Malaysia's road transport is formulated. • Sensible policy options to achieve the CO 2 emissions reduction target are provided. • Increase in fuel price has induced shift towards fuel efficient vehicles. • The CO 2 emissions can be reduced up to 5.7 MtCO 2 with combination of mitigation policies.

  9. Potential and economics of CO2 sequestration

    International Nuclear Information System (INIS)

    Jean-Baptiste, Ph.; Ciais, Ph.; Orr, J.

    2001-01-01

    Increasing atmospheric level of greenhouse gases are causing global warming and putting at risk the global climate system. The main anthropogenic greenhouse gas is CO 2 . Some techniques could be used to reduced CO 2 emission and stabilize atmospheric CO 2 concentration, including i) energy savings and energy efficiency, ii) switch to lower carbon content fuels (natural gas) and use energy sources with zero CO 2 emissions such as renewable or nuclear energy, iii) capture and store CO 2 from fossil fuels combustion, and enhance the natural sinks for CO 2 (forests, soils, ocean...). The purpose of this report is to provide an overview of the technology and cost for capture and storage of CO 2 and to review the various options for CO 2 sequestration by enhancing natural carbon sinks. Some of the factors which will influence application, including environmental impact, cost and efficiency, are discussed. Capturing CO 2 and storing it in underground geological reservoirs appears as the best environmentally acceptable option. It can be done with existing technology, however, substantial R and D is needed to improve available technology and to lower the cost. Applicable to large CO 2 emitting industrial facilities such as power plants, cement factories, steel industry, etc., which amount to about 30% of the global anthropic CO 2 emission, it represents a valuable tool in the baffle against global warming. About 50% of the anthropic CO 2 is being naturally absorbed by the biosphere and the ocean. The 'natural assistance' provided by these two large carbon reservoirs to the mitigation of climate change is substantial. The existing natural sinks could be enhanced by deliberate action. Given the known and likely environmental consequences, which could be very damaging indeed, enhancing ocean sinks does not appears as a satisfactory option. In contrast, the promotion of land sinks through demonstrated carbon-storing approach to agriculture, forests and land management could

  10. Ni–Fe–S Cubanes in CO2 Reduction Electrocatalysis

    DEFF Research Database (Denmark)

    Varley, J. B.; Hansen, H. A.; Ammitzbøll, Nadia Luciw

    2013-01-01

    In this work, we perform extensive mechanistic studies of CO2 (electro)reduction by analogs to the active sites of carbon monoxide dehydrogenase (CODH) enzymes. We explore structure–property relationships for different cluster compositions and interpret the results with a model for CO2...... electroreduction we recently developed and applied to transition metal catalysts. Our results validate the effectiveness of the CODH in catalyzing this important reaction and give insight into why specific cluster compositions were adopted by nature....

  11. CO2 emission reduction potential of large-scale energy efficiency measures in power generation from fossil fuels in China, India, Brazil, Indonesia and South Africa

    OpenAIRE

    Boehme, Benn J.; Krey, Matthias

    2005-01-01

    We quantify the theoretical potential for energy-efficiency CDM projects using best available technology in coal, natural gas or oil fuelled power generation in China, India, Brazil, Indonesia and South Africa, looking at new power plants or retrofit measures. We then discuss the likelihood of the potential emission reductions materialising under CDM. Our results are very sensitive to choices of baseline and project efficiencies and the level of electricity generation from potential emission ...

  12. A human development framework for CO2 reductions.

    Directory of Open Access Journals (Sweden)

    Luís Costa

    Full Text Available Although developing countries are called to participate in CO(2 emission reduction efforts to avoid dangerous climate change, the implications of proposed reduction schemes in human development standards of developing countries remain a matter of debate. We show the existence of a positive and time-dependent correlation between the Human Development Index (HDI and per capita CO(2 emissions from fossil fuel combustion. Employing this empirical relation, extrapolating the HDI, and using three population scenarios, the cumulative CO(2 emissions necessary for developing countries to achieve particular HDI thresholds are assessed following a Development As Usual approach (DAU. If current demographic and development trends are maintained, we estimate that by 2050 around 85% of the world's population will live in countries with high HDI (above 0.8. In particular, 300 Gt of cumulative CO(2 emissions between 2000 and 2050 are estimated to be necessary for the development of 104 developing countries in the year 2000. This value represents between 20 % to 30 % of previously calculated CO(2 budgets limiting global warming to 2 °C. These constraints and results are incorporated into a CO(2 reduction framework involving four domains of climate action for individual countries. The framework reserves a fair emission path for developing countries to proceed with their development by indexing country-dependent reduction rates proportional to the HDI in order to preserve the 2 °C target after a particular development threshold is reached. For example, in each time step of five years, countries with an HDI of 0.85 would need to reduce their per capita emissions by approx. 17% and countries with an HDI of 0.9 by 33 %. Under this approach, global cumulative emissions by 2050 are estimated to range from 850 up to 1100 Gt of CO(2. These values are within the uncertainty range of emissions to limit global temperatures to 2 °C.

  13. A human development framework for CO2 reductions.

    Science.gov (United States)

    Costa, Luís; Rybski, Diego; Kropp, Jürgen P

    2011-01-01

    Although developing countries are called to participate in CO(2) emission reduction efforts to avoid dangerous climate change, the implications of proposed reduction schemes in human development standards of developing countries remain a matter of debate. We show the existence of a positive and time-dependent correlation between the Human Development Index (HDI) and per capita CO(2) emissions from fossil fuel combustion. Employing this empirical relation, extrapolating the HDI, and using three population scenarios, the cumulative CO(2) emissions necessary for developing countries to achieve particular HDI thresholds are assessed following a Development As Usual approach (DAU). If current demographic and development trends are maintained, we estimate that by 2050 around 85% of the world's population will live in countries with high HDI (above 0.8). In particular, 300 Gt of cumulative CO(2) emissions between 2000 and 2050 are estimated to be necessary for the development of 104 developing countries in the year 2000. This value represents between 20 % to 30 % of previously calculated CO(2) budgets limiting global warming to 2 °C. These constraints and results are incorporated into a CO(2) reduction framework involving four domains of climate action for individual countries. The framework reserves a fair emission path for developing countries to proceed with their development by indexing country-dependent reduction rates proportional to the HDI in order to preserve the 2 °C target after a particular development threshold is reached. For example, in each time step of five years, countries with an HDI of 0.85 would need to reduce their per capita emissions by approx. 17% and countries with an HDI of 0.9 by 33 %. Under this approach, global cumulative emissions by 2050 are estimated to range from 850 up to 1100 Gt of CO(2). These values are within the uncertainty range of emissions to limit global temperatures to 2 °C. © 2011 Costa et al.

  14. Reaction mechanisms of CO2 activation and catalytic reduction

    International Nuclear Information System (INIS)

    Wolff, Niklas von

    2016-01-01

    The use of CO 2 as a C1 chemical feedstock for the fine chemical industry is interesting both economically and ecologically, as CO 2 is non-toxic, abundant and cheap. Nevertheless, transformations of CO 2 into value-added products is hampered by its high thermodynamic stability and its inertness toward reduction. In order to design new catalysts able to overcome this kinetic challenge, a profound understanding of the reaction mechanisms at play in CO 2 reduction is needed. Using novel N/Si+ frustrated Lewis pairs (FLPs), the influence of CO 2 adducts and different hydro-borane reducing agents on the reaction mechanism in the catalytic hydroboration of CO 2 were investigated, both by DFT calculations and experiments. In a second step, the reaction mechanism of a novel reaction for the creation of C-C bonds from CO 2 and pyridyl-silanes (C 5 H 4 N-SiMe 3 ) was analyzed by DFT calculations. It was shown that CO 2 plays a double role in this transformation, acting both as a catalyst and a C1-building block. The fine understanding of this transformation then led to the development of a novel approach for the synthesis of sulfones and sulfonamides. Starting from SO 2 and aromatic silanes/amine silanes, these products were obtained in a single step under metal-free conditions. Noteworthy, sulfones and sulfonamides are common motifs in organic chemistry and found in a variety of highly important drugs. Finally, this concept was extended to aromatic halides as coupling partners, and it was thus shown for the first time that a sulfonylative Hiyama reaction is a possible approach to the synthesis of sulfones. (author) [fr

  15. CO2 sequestration. World CO2 emission reduction by forest plantations on agricultural land up to 2050

    International Nuclear Information System (INIS)

    Dameron, V.; Barbier, C.; Riedacker, A.

    2005-01-01

    The main objective of this study was to determine the possible contribution on CO 2 emission reductions of new forest plantations on agricultural land which may become available in the world from now to 2050. Emission reductions have been calculated by taking into account potential changes in carbon stocks on afforested land (in biomass and soil) and replacement with biomass of fossil fuel and material such as steel, aluminium or concrete. Increase of carbon stocks in wood as building material and final conversion of wood recycled from buildings into energy to replace fossil fuel have also been taken into account. CO 2 emission reductions (or carbon benefits) from afforested agricultural land become significant only after 2030 or 2050, and even at a later stage with long rotations. In the case of the latter, about 100 years are needed to get the full benefits. Forest plantations can therefore only be considered as long term options

  16. CuZn Alloy- Based Electrocatalyst for CO2 Reduction

    KAUST Repository

    Alazmi, Amira

    2014-01-01

    , especially when the electronic energy is derived from renewable energies, such as solar, wind, geo-thermal and tidal. To achieve this goal, the development of an efficient electrocatalyst for CO2 reduction is essential. In this thesis, studies on CuZn alloys

  17. Estimate of Possible CO2 Emission Reduction in Slovenia

    International Nuclear Information System (INIS)

    Plavcak, V.-P.; Jevsek, F.; Tirsek, A.

    1998-01-01

    The first estimation of possible CO 2 emission reduction, according to the obligations from Kyoto Protocol, is prepared. The results show that the required 8% reduction of greenhouses gases in Slovenia in the period from 2008 to 2012 with regard to year 1986 will require a through analytical treatment not only in electric power sector but also in transport and industry sectors, which are the main pollutants. (author)

  18. Radiolytic reduction of nifurtimose by CO2-· free radicals

    International Nuclear Information System (INIS)

    Filali-Mouhim, A.; Champion, B.; Jore, D.; Ferradini, C.; Hickel, B.

    1991-01-01

    Nifurtimox is an antiparasitic drug often used in the treatment of the Chagas disease. Its therapeutic action seems to involve its monoelectronic reduction leading to a reduced radical capable of providing superoxide anion by reaction with oxygen. The oxidation reduction mechanisms involved in this action have been studied by steady state and pulse radiolysis methods. This study is devoted to the monoelectronic exchanges observed in the absence of air, the reducing radicals being the CO 2 - · anions [fr

  19. Assesment of Energy Options for CO2 Emission Reduction

    International Nuclear Information System (INIS)

    Cavlina, Nikola

    2014-01-01

    Since the 1992 Earth Summit in Rio de Janeiro, global anthropogenic CO 2 emissions grew by 52% which caused an increase in 10.8% in the CO 2 concentration in the atmosphere, and it tipped the 400 ppm mark in May 2013. The Fifth Assessment Report on climate impacts from the Intergovernmental Panel on Climate Change (IPCC) confirmed earlier warnings that climate change is already stressing human communities, agriculture, and natural ecosystems, and the effects are likely to increase in the future. While European Union has long been committed to lowering carbon emissions, this places additional pressure on current EU goals for energy sector that includes significant reduction of CO 2 emissions. Current EU commitment has been formalized in so-called '20-20-20' plan, reducing carbon emissions, increasing energy efficiency and increasing energy production from renewables by 20% by 2020. Some EU member states are even more ambitious, like United Kingdom, planning to reduce carbon emissions by 80% by 2050. Bulk of carbon reduction will have to be achived in energy sector. In the power industry, most popular solution is use of solar and wind power. Since their production varies significantly during the day, for the purpose of base-load production they can be paired with gas-fired power plant. Other possible CO 2 -free solution is nuclear power plant. In this invited lecture, predicted cost of energy production for newly bulit nuclear power plant and newly built combination of wind or solar and gas-fired power plant are compared. Comparison was done using Levelized Unit of Energy Cost (LUEC). Calculations were performed using the Monte Carlo method. For input parameters that have biggest uncertainty (gas cost, CO 2 emission fee) those uncertainties were addressed not only through probability distribution around predicted value, but also through different scenarious. (author)

  20. Strategic research on CO2 emission reduction for China. Application of MARKAL to China energy system

    International Nuclear Information System (INIS)

    Wang Yongping

    1995-09-01

    MARKAL was applied to the energy system for analyzing the CO 2 emission reduction in China over the time period from 1990 to 2050. First the Chinese Reference Energy System (CRES) was established based on the framework of MARKAL model. The following conclusions can be drawn from this study. When shifting from scenario LH (low useful energy demand and high import fuel prices) to HL (high demand and low prices), another 33 EJ of primary energy will be consumed and another 2.31 billion tons of CO 2 will be emitted in 2050. Detailed analyses on the disaggregation of CO 2 emissions by Kaya Formula show. The energy intensity (primary energy/GDP) decreases much faster in scenario HL, but the higher growth rate of GDP per capita is the overwhelming factor that results in higher CO 2 emission per capita in the baseline case of scenario HL in comparison with LH. When the carbon taxes are imposed on CO 2 emissions, the residential sector will make the biggest contribution to CO 2 emission abatement from a long-term point of view. However, it's difficult to stabilize CO 2 emission per capita before 2030 in both scenarios even with heavy carbon taxes. When nuclear moratorium occurs, more 560 million tons of CO 2 will be emitted to the atmosphere in 2050 under the same CO 2 tax regime. From the analysis of value flow, CO 2 emission reduction depends largely on new or advanced technologies particularly in the field of electricity generation. The competent technologies switch to those CO 2 less-emitting technologies when surcharging CO 2 emissions. Nuclear power shows significant potential in saving fossil energy resources and reducing CO 2 emissions. (J.P.N.)

  1. CO2 reduction strategies for the Czech Republic

    International Nuclear Information System (INIS)

    De Kruijk, H.; Van den Broek, M.A.; Van Harmelen, T.; Van Oostvoorn, F.; Maly, M.

    1994-08-01

    Reduction of CO 2 emissions now has high priority on the international political agenda. The UN Convention on Climate Change provides countries the option for fulfilling the CO 2 reduction obligations individually or jointly. But before identifying opportunities, a reference path or scenario is needed to indicate how emissions will vary without joint implementation of projects or policies. This paper looks at the situation in the Czech Republic. First objective of the study concerns collecting information on CO 2 emissions in the Czech Republic, a reference scenario for CO 2 developments, and the reduction scope till the year 2015. Second objective is development of CEC energy/environmental model EFOM-ENV (Energy Flow and Optimization Model - ENVironment) for the Czech Republic. In the new orientation towards a market economy it is important to start preparing policy recommendations for energy and environmental needs based on the least cost approach. Presently the energy/environmental model EFOM-ENV is used for this type of studies by CEC, Directorate-General 12, and research institutes in almost all EC countries. It showed usefulness in EC countries for developing integrated energy /environmental strategies. Furthermore, based on its experience with this type of studies, the Netherlands Energy Research Foundation has the last years developed a GAMS PC-version of EFOM-ENV, very flexible and efficient to use. Increasing international cooperation in areas of energy and environmental policies requires a common analytical approach. Particularly for preparing harmonized emission control policies in Europe the use of the EC model EFOM-ENV for all Central European countries can provide comparable and useful insight in the relation between energy use and emissions in Central Europe. In fact similar studies have been and will be conducted for the Slovak Republic, Hungary, Bulgaria, other Central European countries. 4 figs., 5 tabs., 6 refs

  2. Study on CO2 emission reduction using ENPEP in Korea

    International Nuclear Information System (INIS)

    Moon, K. H.; Kim, S. S.; Song, K. D.; Im, C. Y.

    2003-01-01

    ENPEP was used to analyze the role of nuclear power in mitigating carbon emission in power generation sector. In this study, base scenario reflects business as usual case in Korea. Additional two scenarios were established. One stands for fuel switch scenario, where nuclear power plants scheduled to be introduced after 2008 were assumed to be replaced by Coal Power Plant, the other one is established to see the impact of carbon tax. In this scenario carbon tax(50$/ton-C0 2 ) is imposed on coal power plants from 2008. It is resulted that fuel switch from nuclear to coal in power generation sector has a great effect on CO 2 emission, while carbon tax imposition makes a slight contribution to the reduction of CO 2 emission. These findings mean that the role of nuclear power in Korea is important in view of the GHG mitigation

  3. Controlling selectivities in CO2 reduction through mechanistic understanding

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiang; Shi, Hui; Szanyi, János

    2017-09-11

    Catalytic CO2 conversion to energy carriers and intermediates is of utmost importance to energy and environmental goals. However, the lack of fundamental understanding of the reaction mechanism renders designing a selective catalyst inefficient. We performed operando FTIR/SSITKA experiments to understand the correlation between the kinetics of product formation and that of surface species conversion during CO2 reduction over Pd/Al2O3 catalysts. We found that the rate-determining step for CO formation is the conversion of adsorbed formate, while that for CH4 formation is the hydrogenation of adsorbed carbonyl. The balance of the hydrogenation kinetics between adsorbed formates and carbonyls governs the selectivities to CH4 and CO. We demonstrated how this knowledge can be used to design catalysts to achieve high selectivities to desired products.

  4. Mesostructure-Induced Selectivity in CO2 Reduction Catalysis.

    Science.gov (United States)

    Hall, Anthony Shoji; Yoon, Youngmin; Wuttig, Anna; Surendranath, Yogesh

    2015-12-02

    Gold inverse opal (Au-IO) thin films are active for CO2 reduction to CO with high efficiency at modest overpotentials and high selectivity relative to hydrogen evolution. The specific activity for hydrogen evolution diminishes by 10-fold with increasing porous film thickness, while CO evolution activity is largely unchanged. We demonstrate that the origin of hydrogen suppression in Au-IO films stems from the generation of diffusional gradients within the pores of the mesostructured electrode rather than changes in surface faceting or Au grain size. For electrodes with optimal mesoporosity, 99% selectivity for CO evolution can be obtained at overpotentials as low as 0.4 V. These results establish electrode mesostructuring as a complementary method for tuning selectivity in CO2-to-fuels catalysis.

  5. Realizing CO2 emission reduction through industrial symbiosis: A cement production case study for Kawasaki

    OpenAIRE

    Hashimoto, Shizuka; Fujita, Tsuyoshi; Geng, Yong; Nagasawa, Emiri

    2010-01-01

    This article is one effort to examine the present and potential performances of CO2 emission reduction though industrial symbiosis by employing a case study approach and life cycle CO2 analysis for alternative industrial symbiosis scenarios. As one of the first and the best-known eco-town projects, Kawasaki Eco-town was chosen as a case study area. First, the current industrial symbiosis practices in this area are introduced. To evaluate the potential of reducing the total CO2 emission throug...

  6. Polyoxometalate-Promoted Electrocatalytic CO2 Reduction at Nanostructured Silver in Dimethylformamide.

    Science.gov (United States)

    Guo, Si-Xuan; Li, Fengwang; Chen, Lu; MacFarlane, Douglas R; Zhang, Jie

    2018-04-18

    Electrochemical reduction of CO 2 is a promising method to convert CO 2 into fuels or useful chemicals, such as carbon monoxide (CO), hydrocarbons, and alcohols. In this study, nanostructured Ag was obtained by electrodeposition of Ag in the presence of a Keggin type polyoxometalate, [PMo 12 O 40 ] 3- (PMo). Metallic Ag is formed upon reduction of Ag + . Adsorption of PMo on the surface of the newly formed Ag lowers its surface energy thus stabilizes the nanostructure. The electrocatalytic performance of this Ag-PMo nanocomposite for CO 2 reduction was evaluated in a CO 2 saturated dimethylformamide medium containing 0.1 M [ n-Bu 4 N]PF 6 and 0.5% (v/v) added H 2 O. The results show that this Ag-PMo nanocomposite can catalyze the reduction of CO 2 to CO with an onset potential of -1.70 V versus Fc 0/+ , which is only 0.29 V more negative than the estimated reversible potential (-1.41 V) for this process and 0.70 V more positive than that on bulk Ag metal. High faradaic efficiencies of about 90% were obtained over a wide range of applied potentials. A Tafel slope of 60 mV dec -1 suggests that rapid formation of *CO 2 •- is followed by the rate-determining protonation step. This is consistent with the voltammetric data which suggest that the reduced PMo interacts strongly with CO 2 (and presumably CO 2 •- ) and hence promotes the formation of CO 2 •- .

  7. Studies on CO2 removal and reduction. CO2 taisaku kenkyu no genjo

    Energy Technology Data Exchange (ETDEWEB)

    Shindo, Y [National Institute of Materials and Chemical Research, Tsukuba (Japan)

    1993-02-01

    This paper summarizes study trends mainly in CO2 fixing processes. Underground CO2 storage is a most promising method because it can fix a huge amount of CO2 and has low effects on ecological systems. Storing CO2 in ocean includes such methods as storing it in deep oceans; storing it in deep ocean beds; dissolving it into sea water; neutralizing it with calcium carbonates; and precipitating it as dry ice. Japan, disposing CO2 in these ways, may create international problems. Separation of CO2 may use a chemical absorption process as a superior method. Other processes discussed include a physical adsorption method and a membrane separation method. A useful method for CO2 fixation using marine organisms is fixation using coral reefs. This process will require an overall study including circulation of phosphorus and nitrogen. Marine organisms may include planktons and algae. CO2 fixation using land plants may be able to fix one trillion and 8 hundred billion tons of CO2 as converted to carbon. This process would require forest protection, prevention of desertification, and tree planting. Discussions are being given also on improving power generation cycles, recovering CO2 from automotive exhausts, and backfilling carbons into ground by means of photosynthesis. 23 refs., 7 figs., 1 tab.

  8. Reconsideration of atmospheric CO2 lifetime: potential mechanism for explaining CO2 missing sink

    Science.gov (United States)

    Kikuchi, R.; Gorbacheva, T.; Gerardo, R.

    2009-04-01

    Carbon cycle data (Intergovernmental Panel on Climate Change 1996) indicate that fossil fuel use accounts for emissions to the atmosphere of 5.5±0.5 GtC (Gigatons of carbon) annually. Other important processes in the global CO2 budget are tropical deforestation, estimated to generate about 1.6±1.0 GtC/yr; absorption by the oceans, removing about 2.0±0.8 GtC/yr; and regrowth of northern forests, taking up about 0.5±0.5 GtC/yr. However, accurate measurements of CO2 show that the atmosphere is accumulating only about 3.3±0.2 GtC/yr. The imbalance of about 1.3±1.5 GtC/yr, termed the "missing sink", represents the difference between the estimated sources and the estimated sinks of CO2; that is, we do not know where all of the anthropogenic CO2 is going. Several potential mechanisms have been proposed to explain this missing carbon, such as CO2 fertilization, climate change, nitrogen deposition, land use change, forest regrowth et al. Considering the complexity of ecosystem, most of ecosystem model cannot handle all the potential mechanisms to reproduce the real world. It has been believed that the dominant sink mechanism is the fertilizing effects of increased CO2 concentrations in the atmosphere and the addition to soils of fixed nitrogen from fossil-fuel burning and agricultural fertilizers. However, a recent analysis of long-term observations of the change in biomass and growth rates suggests that such fertilization effects are much too small to explain more than a small fraction of the observed sink. In addition, long-term experiments in which small forest patches and other land ecosystems have been exposed to elevated CO2 levels for extended periods show a rapid decrease of the fertilization effect after an initial enhancement. We will explore this question of the missing sink in atmospheric CO2 residence time. Radioactive and stable carbon isotopes (13-C/12-C) show the real CO2 lifetime is about 5 years; i.e. CO2 is quickly taken out of the atmospheric

  9. Subsurface oxide plays a critical role in CO2 activation by Cu(111) surfaces to form chemisorbed CO2, the first step in reduction of CO2.

    Science.gov (United States)

    Favaro, Marco; Xiao, Hai; Cheng, Tao; Goddard, William A; Yano, Junko; Crumlin, Ethan J

    2017-06-27

    A national priority is to convert CO 2 into high-value chemical products such as liquid fuels. Because current electrocatalysts are not adequate, we aim to discover new catalysts by obtaining a detailed understanding of the initial steps of CO 2 electroreduction on copper surfaces, the best current catalysts. Using ambient pressure X-ray photoelectron spectroscopy interpreted with quantum mechanical prediction of the structures and free energies, we show that the presence of a thin suboxide structure below the copper surface is essential to bind the CO 2 in the physisorbed configuration at 298 K, and we show that this suboxide is essential for converting to the chemisorbed CO 2 in the presence of water as the first step toward CO 2 reduction products such as formate and CO. This optimum suboxide leads to both neutral and charged Cu surface sites, providing fresh insights into how to design improved carbon dioxide reduction catalysts.

  10. Use of California biomass in the production of transportation-fuel oxygenates: Estimates for reduction in CO2 emissions and greenhouse gas potential on a life cycle basis

    International Nuclear Information System (INIS)

    Kadam, K. L.; Camobreco, V. J.; Glazebrook, B. E.

    1999-01-01

    A set of environmental flows associated with two disposal options for thee types of California biomass - forest biomass, rice straw, chaparral - over their life cycles were studied, the emphasis being on energy consumption and greenhouse gas emissions. The two options studied were: producing ethyl-tertiary-butyl ether (ETBE) from biomass and biomass burning, and producing methyl-tertiary-butyl ether (MTBE) from natural gas. Results showed a lower (by 40 to 50 per cent) greenhouse effect impact, lower net values for carbon dioxide and fossil fuel energy consumption, and higher net values for renewable energy consumption for the ETBE option. Based on these results, the deployment of the biomass-to-ethanol ETBE option is recommended as the one that contributes most to the reduction of GHG emissions. 12 refs., 2 tabs., 5 figs

  11. Reduction of CO2 emissions by reduction of paper use for publication applications

    Energy Technology Data Exchange (ETDEWEB)

    Van den Reek, J.A.

    1999-10-01

    The main research question of this study is as follows: What is the technical potential for reducing paper use in the field of publication applications in Western Europe within a time frame of 10-20 years, and what will the consequences for CO2 emissions be? To answer this central question we have defined the next four subquestions, all related to Western Europe: (1) How were the historical trends for the consumption figures of publication papers?; (2) What will be the expected publication paper consumption the next 10-20 years based on the historical trends, and what will be the influence on the related CO2 emissions?; (3) What technical opportunities do we see to reduce the future paper consumption trend for publication applications and what will be the individual and cumulative technical potential of these innovations?; (4) Does implementation of the technical opportunities lead to a significant dematerialization effect? Chapter 2 describes the chosen research method. In Chapter 3 we will introduce and define the paper types studied. Furthermore, Chapter 3 describes the detailed division of publication papers we have used in this study and the relationship with pulp and papermaking. After reading this chapter it has to be clear which paper production methods and paper types are (per ton) responsible for how much CO2 emissions. To get an overall-impression of the relevance of certain papers for CO2 emission numbers it is important to have insight into the historical consumption patterns of publication papers. Chapter 4 pays attention to these consumption patterns. Chapter 5 describes the most important trend factors that may influence future paper consumption patterns and in Chapter 6 this is translated into three possible consumption growth scenarios. The first and second growth scenarios are only based on extrapolations from historical figures, the third scenario is based on some of the most significant potential reduction measures. Furthermore, Chapter 6 gives

  12. In situ spectroscopic monitoring of CO2 reduction at copper oxide electrode.

    Science.gov (United States)

    Wang, Liying; Gupta, Kalyani; Goodall, Josephine B M; Darr, Jawwad A; Holt, Katherine B

    2017-04-28

    Copper oxide modified electrodes were investigated as a function of applied electrode potential using in situ infrared spectroscopy and ex situ Raman and X-ray photoelectron spectroscopy. In deoxygenated KHCO 3 electrolyte bicarbonate and carbonate species were found to adsorb to the electrode during reduction and the CuO was reduced to Cu(i) or Cu(0) species. Carbonate was incorporated into the structure and the CuO starting material was not regenerated on cycling to positive potentials. In contrast, in CO 2 saturated KHCO 3 solution, surface adsorption of bicarbonate and carbonate was not observed and adsorption of a carbonato-species was observed with in situ infrared spectroscopy. This species is believed to be activated, bent CO 2 . On cycling to negative potentials, larger reduction currents were observed in the presence of CO 2 ; however, less of the charge could be attributed to the reduction of CuO. In the presence of CO 2 CuO underwent reduction to Cu 2 O and potentially Cu, with no incorporation of carbonate. Under these conditions the CuO starting material could be regenerated by cycling to positive potentials.

  13. Investigation of the charge-transfer in photo-excited nanoparticles for CO2 reduction in non-aqueous media

    Directory of Open Access Journals (Sweden)

    Dimitrijević Nada M.

    2013-01-01

    Full Text Available Photoinduced charge separation in TiO2 and Cu2O semiconductor nanoparticles was examined using Electron Paramagnetic Resonance spectroscopy in order to get insight into the photocatalytic reduction of CO2 in nonaqueous media. For dissolution/grafting of CO2 we have used carboxy-PEG4-amine, and as a solvent poly(ethylene glycol 200. We have found that, in this system, reduction of CO2 starts at potential of -0.5 V vs Ag/AgCl, which is significantly more positive than the potential for electrochemical reduction of CO2 in most organic solvents and water (-2.0 V vs. Ag/AgCl. The electron transfer from excited nanoparticles to CO2 is governed both by thermodynamic and kinetic parameters, namely by the redox potential of conduction band electrons and adsorption/binding of CO2 on the surface of nanoparticles.

  14. Electricity consumption and CO2 capture potential in Spain

    International Nuclear Information System (INIS)

    Romeo, Luis M.; Calvo, Elena; Valero, Antonio; De Vita, Alessia

    2009-01-01

    In this paper, different electricity demand scenarios for Spain are presented. Population, income per capita, energy intensity and the contribution of electricity to the total energy demand have been taken into account in the calculations. Technological role of different generation technologies, i.e. coal, nuclear, renewable, combined cycle (CC), combined heat and power (CHP) and carbon capture and storage (CCS), are examined in the form of scenarios up to 2050. Nine future scenarios corresponding to three electrical demands and three options for new capacity: minimum cost of electricity, minimum CO 2 emissions and a criterion with a compromise between CO 2 and cost (CO 2 -cost criterion) have been proposed. Calculations show reduction in CO 2 emissions from 2020 to 2030, reaching a maximum CO 2 emission reduction of 90% in 2050 in an efficiency scenario with CCS and renewables. The contribution of CCS from 2030 is important with percentage values of electricity production around 22-28% in 2050. The cost of electricity (COE) increases up to 25% in 2030, and then this value remains approximately constant or decreases slightly.

  15. Electrochemical CO2 Reduction by Ni-containing Iron Sulfides: How Is CO2 Electrochemically Reduced at Bisulfide-Bearing Deep-sea Hydrothermal Precipitates?

    International Nuclear Information System (INIS)

    Yamaguchi, Akira; Yamamoto, Masahiro; Takai, Ken; Ishii, Takumi; Hashimoto, Kazuhito; Nakamura, Ryuhei

    2014-01-01

    The discovery of deep-sea hydrothermal vents on the late 1970's has led to many hypotheses concerning chemical evolution in the prebiotic ocean and the early evolution of energy metabolism in ancient Earth. Such studies stand on the quest for the bioenergetic evolution to utilize reducing chemicals such as H 2 for CO 2 reduction and carbon assimilation. In addition to the direct reaction of H 2 and CO 2 , the electrical current passing across a bisulfide-bearing chimney structure has pointed to the possible electrocatalytic CO 2 reduction at the cold ocean-vent interface (R. Nakamura, et al. Angew. Chem. Int. Ed. 2010, 49, 7692 − 7694). To confirm the validity of this hypothesis, here, we examined the energetics of electrocatalytic CO 2 reduction by iron sulfide (FeS) deposits at slightly acidic pH. Although FeS deposits inefficiently reduced CO 2 , the efficiency of the reaction was substantially improved by the substitution of Fe with Ni to form FeNi 2 S 4 (violarite), of which surface was further modified with amine compounds. The potential-dependent activity of CO 2 reduction demonstrated that CO 2 reduction by H 2 in hydrothermal fluids was involved in a strong endergonic electron transfer reaction, suggesting that a naturally occurring proton-motive force (PMF) as high as 200 mV would be established across the hydrothermal vent chimney wall. However, in the chimney structures, H 2 generation competes with CO 2 reduction for electrical current, resulting in rapid consumption of the PMF. Therefore, to maintain the PMF and the electrosynthesis of organic compounds in hydrothermal vent mineral deposits, we propose a homeostatic pH regulation mechanism of FeS deposits, in which elemental hydrogen stored in the hydrothermal mineral deposits is used to balance the consumption of the electrochemical gradient by H 2 generation

  16. The Potential for Forestry to Reduce Net CO2 Emissions

    International Nuclear Information System (INIS)

    Eriksson, Erik

    2006-01-01

    . However, the trees have to be grown on good sites; otherwise long rotations could be better options for broad-leaved stands. In coniferous stands, a shortened rotation period resulted in lower carbon stocks than a prolonged rotation period, but the amount of residues that could substitute fossil fuel increased with a shorter rotation. However, annual rates of carbon accumulation in biomass might decline in both short- and long-rotation stands in the future. If so, carbon sequestration in biomass would not be the best option. In a long-term perspective, wood products could have high potential to reduce net CO 2 emissions, since wood can replace energy-intensive materials like cement, plastics and aluminium. Intensively managed forests (e.g. fertilized forests or shortened rotation lengths) could contribute more to reductions in CO 2 emissions than current forest management. Using forest products (i.e. wood products and biofuel) is probably more important than storing carbon in biomass and soil, but it is necessary to conserve the existing stocks. Intensive forest management and increased use of biomass may, however, conflict with environmental quality objectives

  17. Electrochemical Reduction of CO2 at Metal Electrodes in a Distillable Ionic Liquid.

    Science.gov (United States)

    Chen, Lu; Guo, Si-Xuan; Li, Fengwang; Bentley, Cameron; Horne, Mike; Bond, Alan M; Zhang, Jie

    2016-06-08

    The electroreduction of CO2 in the distillable ionic liquid dimethylammonium dimethylcarbamate (dimcarb) has been investigated with 17 metal electrodes. Analysis of the electrolysis products reveals that aluminum, bismuth, lead, copper, nickel, palladium, platinum, iron, molybdenum, titanium and zirconium electroreduce the available protons in dimcarb to hydrogen rather than reducing CO2 . Conversely, indium, tin, zinc, silver and gold are able to catalyze the reduction of CO2 to predominantly carbon monoxide (CO) and to a lesser extent, formate ([HCOO](-) ). In all cases, the applied potential was found to have a minimal influence on the distribution of the reduction products. Overall, indium was found to be the best electrocatalyst for CO2 reduction in dimcarb, with faradaic efficiencies of approximately 45 % and 40 % for the generation of CO and [HCOO](-) , respectively, at a potential of -1.34 V versus Cc(+/0) (Cc(+) =cobaltocenium) employing a dimethylamine to CO2 ratio of less than 1.8:1. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Tackling CO2 reduction in India through use of CO2 capture and storage (CCS): Prospects and challenges

    International Nuclear Information System (INIS)

    Shackley, Simon; Verma, Preeti

    2008-01-01

    CO 2 capture and storage (CCS) is not currently a priority for the Government of India (GOI) because, whilst a signatory to the UNFCCC and Kyoto Protocol, there are no existing greenhouse gas emission reduction targets and most commentators do not envisage compulsory targets for India in the post-2012 phase. The overwhelming priority for the GOI is to sustain a high level of economic growth (8%+) and provision of secure, reliable energy (especially electricity) is one of the widely recognised bottlenecks in maintaining a high growth rate. In such a supply-starved context, it is not easy to envisage adoption of CCS-which increases overall generation capacity and demand for coal without increasing actual electricity supply-as being acceptable. Anything which increases costs-even slightly-is very unlikely to happen, unless it is fully paid for by the international community. The majority viewpoint of the industry and GOI interviewees towards CCS appears to be that it is a frontier technology, which needs to be developed further in the Annex-1 countries to bring down the cost through RD and D and deployment. More RD and D is required to assess in further detail the potential for CO 2 storage in geological reservoirs in India and the international community has an important role to play in cultivating such research

  19. Enhanced electrocatalytic CO2 reduction via field-induced reagent concentration

    Science.gov (United States)

    Liu, Min; Pang, Yuanjie; Zhang, Bo; de Luna, Phil; Voznyy, Oleksandr; Xu, Jixian; Zheng, Xueli; Dinh, Cao Thang; Fan, Fengjia; Cao, Changhong; de Arquer, F. Pelayo García; Safaei, Tina Saberi; Mepham, Adam; Klinkova, Anna; Kumacheva, Eugenia; Filleter, Tobin; Sinton, David; Kelley, Shana O.; Sargent, Edward H.

    2016-09-01

    Electrochemical reduction of carbon dioxide (CO2) to carbon monoxide (CO) is the first step in the synthesis of more complex carbon-based fuels and feedstocks using renewable electricity. Unfortunately, the reaction suffers from slow kinetics owing to the low local concentration of CO2 surrounding typical CO2 reduction reaction catalysts. Alkali metal cations are known to overcome this limitation through non-covalent interactions with adsorbed reagent species, but the effect is restricted by the solubility of relevant salts. Large applied electrode potentials can also enhance CO2 adsorption, but this comes at the cost of increased hydrogen (H2) evolution. Here we report that nanostructured electrodes produce, at low applied overpotentials, local high electric fields that concentrate electrolyte cations, which in turn leads to a high local concentration of CO2 close to the active CO2 reduction reaction surface. Simulations reveal tenfold higher electric fields associated with metallic nanometre-sized tips compared to quasi-planar electrode regions, and measurements using gold nanoneedles confirm a field-induced reagent concentration that enables the CO2 reduction reaction to proceed with a geometric current density for CO of 22 milliamperes per square centimetre at -0.35 volts (overpotential of 0.24 volts). This performance surpasses by an order of magnitude the performance of the best gold nanorods, nanoparticles and oxide-derived noble metal catalysts. Similarly designed palladium nanoneedle electrocatalysts produce formate with a Faradaic efficiency of more than 90 per cent and an unprecedented geometric current density for formate of 10 milliamperes per square centimetre at -0.2 volts, demonstrating the wider applicability of the field-induced reagent concentration concept.

  20. A multinational model for CO2 reduction: defining boundaries of future CO2 emissions in nine countries

    International Nuclear Information System (INIS)

    Kram, Tom; Hill, Douglas.

    1996-01-01

    A need to make substantial future reductions in greenhouse gas emissions would require major changes in national energy systems. Nine industrialized countries have explored the technical boundaries of CO 2 emission restrictions during the next 40 to 50 years using comparable scenario assumptions and a standard model, MARKAL. Quantitative results for the countries are shown side by side in a set of energy maps that compare the least-cost evolution of the national energy systems by the main factors that contribute to CO 2 emissions. The ability to restrict future CO 2 emissions and the most cost-effective measures for doing so differ among the countries; an international agreement that would mandate substantial emission restrictions among countries by an equal percentage reduction is clearly impossible. The results are a first step toward a basis for allocating such international reductions, and the multinational process by which they were produced provides an example for further international greenhouse gas abatement costing studies. (Author)

  1. Strength Reduction of Coal Pillar after CO2 Sequestration in Abandoned Coal Mines

    Directory of Open Access Journals (Sweden)

    Qiuhao Du

    2017-02-01

    Full Text Available CO2 geosequestration is currently considered to be the most effective and economical method to dispose of artificial greenhouse gases. There are a large number of coal mines that will be scrapped, and some of them are located in deep formations in China. CO2 storage in abandoned coal mines will be a potential option for greenhouse gas disposal. However, CO2 trapping in deep coal pillars would induce swelling effects of coal matrix. Adsorption-induced swelling not only modifies the volume and permeability of coal mass, but also causes the basic physical and mechanical properties changing, such as elastic modulus and Poisson ratio. It eventually results in some reduction in pillar strength. Based on the fractional swelling as a function of time and different loading pressure steps, the relationship between volumetric stress and adsorption pressure increment is acquired. Eventually, this paper presents a theory model to analyze the pillar strength reduction after CO2 adsorption. The model provides a method to quantitatively describe the interrelation of volumetric strain, swelling stress, and mechanical strength reduction after gas adsorption under the condition of step-by-step pressure loading and the non-Langmuir isothermal model. The model might have a significantly important implication for predicting the swelling stress and mechanical behaviors of coal pillars during CO2 sequestration in abandoned coal mines.

  2. Investigation of CO2 emission reduction strategy from in-use gasoline vehicle

    Science.gov (United States)

    Choudhary, Arti; Gokhale, Sharad

    2016-04-01

    On road transport emissions is kicking off in Indian cities due to high levels of urbanization and economic growth during the last decade in Indian subcontinent. In 1951, about 17% of India's population were living in urban areas that increased to 32% in 2011. Currently, India is fourth largest Green House Gas (GHG) emitter in the world, with its transport sector being the second largest contributor of CO2 emissions. For achieving prospective carbon reduction targets, substantial opportunity among in-use vehicle is necessary to quantify. Since, urban traffic flow and operating condition has significant impact on exhaust emission (Choudhary and Gokhale, 2016). This study examined the influence of vehicular operating kinetics on CO2 emission from predominant private transportation vehicles of Indian metropolitan city, Guwahati. On-board instantaneous data were used to quantify the impact of CO2 emission on different mileage passenger cars and auto-rickshaws at different times of the day. Further study investigates CO2 emission reduction strategies by using International Vehicle Emission (IVE) model to improve co-benefit in private transportation by integrated effort such as gradual phase-out of inefficient vehicle and low carbon fuel. The analysis suggests that fuel type, vehicles maintenance and traffic flow management have potential for reduction of urban sector GHG emissions. Keywords: private transportation, CO2, instantaneous emission, IVE model Reference Choudhary, A., Gokhale, S. (2016). Urban real-world driving traffic emissions during interruption and congestion. Transportation Research Part D: Transport and Environment 43: 59-70.

  3. CO2 emissions and mitigation potential in China's ammonia industry

    International Nuclear Information System (INIS)

    Zhou Wenji; Zhu Bing; Li Qiang; Ma Tieju; Hu Shanying; Griffy-Brown, Charla

    2010-01-01

    Significant pressure from increasing CO 2 emissions and energy consumption in China's industrialization process has highlighted a need to understand and mitigate the sources of these emissions. Ammonia production, as one of the most important fundamental industries in China, represents those heavy industries that contribute largely to this sharp increasing trend. In the country with the largest population in the world, ammonia output has undergone fast growth spurred by increasing demand for fertilizer of food production since 1950s. However, various types of technologies implemented in the industry make ammonia plants in China operate with huge differences in both energy consumption and CO 2 emissions. With consideration of these unique features, this paper attempts to estimate the amount of CO 2 emission from China's ammonia production, and analyze the potential for carbon mitigation in the industry. Based on the estimation, related policy implications and measures required to realize the potential for mitigation are also discussed.

  4. Determining CO2 storage potential during miscible CO2 enhanced oil recovery: Noble gas and stable isotope tracers

    Science.gov (United States)

    Shelton, Jenna L.; McIntosh, Jennifer C.; Hunt, Andrew; Beebe, Thomas L; Parker, Andrew D; Warwick, Peter D.; Drake, Ronald; McCray, John E.

    2016-01-01

    Rising atmospheric carbon dioxide (CO2) concentrations are fueling anthropogenic climate change. Geologic sequestration of anthropogenic CO2 in depleted oil reservoirs is one option for reducing CO2 emissions to the atmosphere while enhancing oil recovery. In order to evaluate the feasibility of using enhanced oil recovery (EOR) sites in the United States for permanent CO2 storage, an active multi-stage miscible CO2flooding project in the Permian Basin (North Ward Estes Field, near Wickett, Texas) was investigated. In addition, two major natural CO2 reservoirs in the southeastern Paradox Basin (McElmo Dome and Doe Canyon) were also investigated as they provide CO2 for EOR operations in the Permian Basin. Produced gas and water were collected from three different CO2 flooding phases (with different start dates) within the North Ward Estes Field to evaluate possible CO2 storage mechanisms and amounts of total CO2retention. McElmo Dome and Doe Canyon were sampled for produced gas to determine the noble gas and stable isotope signature of the original injected EOR gas and to confirm the source of this naturally-occurring CO2. As expected, the natural CO2produced from McElmo Dome and Doe Canyon is a mix of mantle and crustal sources. When comparing CO2 injection and production rates for the CO2 floods in the North Ward Estes Field, it appears that CO2 retention in the reservoir decreased over the course of the three injections, retaining 39%, 49% and 61% of the injected CO2 for the 2008, 2010, and 2013 projects, respectively, characteristic of maturing CO2 miscible flood projects. Noble gas isotopic composition of the injected and produced gas for the flood projects suggest no active fractionation, while δ13CCO2 values suggest no active CO2dissolution into formation water, or mineralization. CO2 volumes capable of dissolving in residual formation fluids were also estimated along with the potential to store pure-phase supercritical CO2. Using a combination

  5. Potential of European 14CO2 observation network to estimate the fossil fuel CO2 emissions via atmospheric inversions

    Science.gov (United States)

    Wang, Yilong; Broquet, Grégoire; Ciais, Philippe; Chevallier, Frédéric; Vogel, Felix; Wu, Lin; Yin, Yi; Wang, Rong; Tao, Shu

    2018-03-01

    Combining measurements of atmospheric CO2 and its radiocarbon (14CO2) fraction and transport modeling in atmospheric inversions offers a way to derive improved estimates of CO2 emitted from fossil fuel (FFCO2). In this study, we solve for the monthly FFCO2 emission budgets at regional scale (i.e., the size of a medium-sized country in Europe) and investigate the performance of different observation networks and sampling strategies across Europe. The inversion system is built on the LMDZv4 global transport model at 3.75° × 2.5° resolution. We conduct Observing System Simulation Experiments (OSSEs) and use two types of diagnostics to assess the potential of the observation and inverse modeling frameworks. The first one relies on the theoretical computation of the uncertainty in the estimate of emissions from the inversion, known as posterior uncertainty, and on the uncertainty reduction compared to the uncertainty in the inventories of these emissions, which are used as a prior knowledge by the inversion (called prior uncertainty). The second one is based on comparisons of prior and posterior estimates of the emission to synthetic true emissions when these true emissions are used beforehand to generate the synthetic fossil fuel CO2 mixing ratio measurements that are assimilated in the inversion. With 17 stations currently measuring 14CO2 across Europe using 2-week integrated sampling, the uncertainty reduction for monthly FFCO2 emissions in a country where the network is rather dense like Germany, is larger than 30 %. With the 43 14CO2 measurement stations planned in Europe, the uncertainty reduction for monthly FFCO2 emissions is increased for the UK, France, Italy, eastern Europe and the Balkans, depending on the configuration of prior uncertainty. Further increasing the number of stations or the sampling frequency improves the uncertainty reduction (up to 40 to 70 %) in high emitting regions, but the performance of the inversion remains limited over low

  6. Potential of European 14CO2 observation network to estimate the fossil fuel CO2 emissions via atmospheric inversions

    Directory of Open Access Journals (Sweden)

    Y. Wang

    2018-03-01

    Full Text Available Combining measurements of atmospheric CO2 and its radiocarbon (14CO2 fraction and transport modeling in atmospheric inversions offers a way to derive improved estimates of CO2 emitted from fossil fuel (FFCO2. In this study, we solve for the monthly FFCO2 emission budgets at regional scale (i.e., the size of a medium-sized country in Europe and investigate the performance of different observation networks and sampling strategies across Europe. The inversion system is built on the LMDZv4 global transport model at 3.75°  ×  2.5° resolution. We conduct Observing System Simulation Experiments (OSSEs and use two types of diagnostics to assess the potential of the observation and inverse modeling frameworks. The first one relies on the theoretical computation of the uncertainty in the estimate of emissions from the inversion, known as posterior uncertainty, and on the uncertainty reduction compared to the uncertainty in the inventories of these emissions, which are used as a prior knowledge by the inversion (called prior uncertainty. The second one is based on comparisons of prior and posterior estimates of the emission to synthetic true emissions when these true emissions are used beforehand to generate the synthetic fossil fuel CO2 mixing ratio measurements that are assimilated in the inversion. With 17 stations currently measuring 14CO2 across Europe using 2-week integrated sampling, the uncertainty reduction for monthly FFCO2 emissions in a country where the network is rather dense like Germany, is larger than 30 %. With the 43 14CO2 measurement stations planned in Europe, the uncertainty reduction for monthly FFCO2 emissions is increased for the UK, France, Italy, eastern Europe and the Balkans, depending on the configuration of prior uncertainty. Further increasing the number of stations or the sampling frequency improves the uncertainty reduction (up to 40 to 70 % in high emitting regions, but the performance of the inversion

  7. Effect of copper oxide electrocatalyst on CO2 reduction using Co3O4 as anode

    Directory of Open Access Journals (Sweden)

    V.S.K. Yadav

    2016-09-01

    Full Text Available The reduction of carbon dioxide (CO2 to products electrochemically (RCPE in 0.5 M NaHCO3 and Na2CO3 liquid phase electrolyte solutions was investigated. Cobalt oxide (Co3O4 as anode and cuprous oxide (Cu2O as the cathode were considered, respectively. The impacts of applied potential with time of reaction during reduction of CO2 to products were studied. The anode and cathode were prepared by depositing electrocatalysts on the graphite plate. Ultra-fast liquid chromatography (UFLC was used to analyze the products obtained from the reduction of CO2. The feasible way of reduction by applying voltages with current densities was clearly correlated. The results illustrate the capability of electrocatalyst successfully to remove atmospheric CO2 in the form of valuable chemicals. Maximum Faradaic efficiency of ethanol was 98.1% at 2 V and for formic acid (36.6% at 1.5 V was observed in NaHCO3. On the other hand, in Na2CO3 electrolyte solution maximum efficiency for ethanol was 55.21% at 1.5 V and 25.1% for formic acid at 2 V. In both electrolytes other end products like methanol, propanol, formaldehyde and acetic acid were formed at various applied voltage and output current densities.

  8. Shape-Dependent Electrocatalytic Reduction of CO2 to CO on Triangular Silver Nanoplates.

    Science.gov (United States)

    Liu, Subiao; Tao, Hongbiao; Zeng, Li; Liu, Qi; Xu, Zhenghe; Liu, Qingxia; Luo, Jing-Li

    2017-02-15

    Electrochemical reduction of CO 2 (CO 2 RR) provides great potential for intermittent renewable energy storage. This study demonstrates a predominant shape-dependent electrocatalytic reduction of CO 2 to CO on triangular silver nanoplates (Tri-Ag-NPs) in 0.1 M KHCO 3 . Compared with similarly sized Ag nanoparticles (SS-Ag-NPs) and bulk Ag, Tri-Ag-NPs exhibited an enhanced current density and significantly improved Faradaic efficiency (96.8%) and energy efficiency (61.7%), together with a considerable durability (7 days). Additionally, CO starts to be observed at an ultralow overpotential of 96 mV, further confirming the superiority of Tri-Ag-NPs as a catalyst for CO 2 RR toward CO formation. Density functional theory calculations reveal that the significantly enhanced electrocatalytic activity and selectivity at lowered overpotential originate from the shape-controlled structure. This not only provides the optimum edge-to-corner ratio but also dominates at the facet of Ag(100) where it requires lower energy to initiate the rate-determining step. This study demonstrates a promising approach to tune electrocatalytic activity and selectivity of metal catalysts for CO 2 RR by creating optimal facet and edge site through shape-control synthesis.

  9. Throwing new light on the reduction of CO2.

    Science.gov (United States)

    Ozin, Geoffrey A

    2015-03-18

    While the chemical energy in fossil fuels has enabled the rapid rise of modern civilization, their utilization and accompanying anthropogenic CO2 emissions is occurring at a rate that is outpacing nature's carbon cycle. Its effect is now considered to be irreversible and this could lead to the demise of human society. This is a complex issue without a single solution, yet from the burgeoning global research activity and development in the field of CO2 capture and utilization, there is light at the end of the tunnel. In this article a couple of recent advances are illuminated. Attention is focused on the discovery of gas-phase, light-assisted heterogeneous catalytic materials and processes for CO2 photoreduction that operate at sufficiently high rates and conversion efficiencies, and under mild conditions, to open a new pathway for an energy transition from today's "fossil fuel economy" to a new and sustainable "CO2 economy". Whichever of the competing CO2 capture and utilization approaches proves to be the best way forward for the development of a future CO2-based solar fuels economy, hopefully this can occur in a period short enough to circumvent the predicted adverse consequences of greenhouse gas climate change. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Quantitative analysis of an engineered CO2-fixing Escherichia coli reveals great potential of heterotrophic CO2 fixation.

    Science.gov (United States)

    Gong, Fuyu; Liu, Guoxia; Zhai, Xiaoyun; Zhou, Jie; Cai, Zhen; Li, Yin

    2015-01-01

    Production of fuels from the abundant and wasteful CO2 is a promising approach to reduce carbon emission and consumption of fossil fuels. Autotrophic microbes naturally assimilate CO2 using energy from light, hydrogen, and/or sulfur. However, their slow growth rates call for investigation of the possibility of heterotrophic CO2 fixation. Although preliminary research has suggested that CO2 fixation in heterotrophic microbes is feasible after incorporation of a CO2-fixing bypass into the central carbon metabolic pathway, it remains unclear how much and how efficient that CO2 can be fixed by a heterotrophic microbe. A simple metabolic flux index was developed to indicate the relative strength of the CO2-fixation flux. When two sequential enzymes of the cyanobacterial Calvin cycle were incorporated into an E. coli strain, the flux of the CO2-fixing bypass pathway accounts for 13 % of that of the central carbon metabolic pathway. The value was increased to 17 % when the carbonic anhydrase involved in the cyanobacterial carbon concentrating mechanism was introduced, indicating that low intracellular CO2 concentration is one limiting factor for CO2 fixation in E. coli. The engineered CO2-fixing E. coli with carbonic anhydrase was able to fix CO2 at a rate of 19.6 mg CO2 L(-1) h(-1) or the specific rate of 22.5 mg CO2 g DCW(-1) h(-1). This CO2-fixation rate is comparable with the reported rates of 14 autotrophic cyanobacteria and algae (10.5-147.0 mg CO2 L(-1) h(-1) or the specific rates of 3.5-23.7 mg CO2 g DCW(-1) h(-1)). The ability of CO2 fixation was created and improved in E. coli by incorporating partial cyanobacterial Calvin cycle and carbon concentrating mechanism, respectively. Quantitative analysis revealed that the CO2-fixation rate of this strain is comparable with that of the autotrophic cyanobacteria and algae, demonstrating great potential of heterotrophic CO2 fixation.

  11. Identifying Activity Descriptors for CO2 Electro-Reduction to Methanol on Rutile (110) Surfaces

    DEFF Research Database (Denmark)

    Bhowmik, Arghya; Hansen, Heine Anton; Vegge, Tejs

    2015-01-01

    Electrocatalytic reduction of CO2 to liquid fuels using energy from renewable sources has the potential to form the basis of a carbon neutral sustainable energy system, while integrating seamlessly in the established infrastructure1. Storing intermittent renewable energy in a chemical fuel...... towards electrocatalytic production of methanol. We would like to acknowledge the Lundbeck Foundation for financial support of this work. References: 1. Lewis, N. S. & Nocera, D. G. Powering the planet: chemical challenges in solar energy utilization. Proc. Natl. Acad. Sci. U. S. A.103,15729–35 (2006......., Ali, I., Jansen, M. & Omanovic, S. Electrochemical reduction of CO 2 in an aqueous electrolyte employing an iridium/ruthenium-oxide electrode. Can. J. Chem. Eng. (2014). doi:10.1002/cjce.22110 6. Nørskov, J. K. et al. Origin of the Overpotential for Oxygen Reduction at a Fuel-Cell Cathode. J. Phys...

  12. Regional CO2 budget, countermeasures and reduction aims for the Alpine tourist region of Davos, Switzerland

    International Nuclear Information System (INIS)

    Walz, A.; Calonder, G.-P.; Hagedorn, F.; Lardelli, C.; Lundstroem, C.; Stoeckli, V.

    2008-01-01

    In its latest report, the Intergovernmental Panel on Climate Change (IPCC) concludes that global climate change can still be slowed down if greenhouse gas emissions are rapidly and strongly reduced. We present a detailed regional CO 2 budget for the Alpine tourist region of Davos, Switzerland, including emissions and potential sinks. The aim of the study was (1) to estimate the most important CO 2 sources and sinks, (2) to identify the most efficient reduction measures and (3) to assess the feasibility of different reduction targets. The results show that the emissions due to heating contribute to a proportion of 86.3% to the total budget, which is mainly due to the harsh local climate and the tourism-focused local economy. They also show that the yearly CO 2 emissions per capita in Davos exceed the Swiss average of 6 tonnes by 25%. The augmentation of the carbon pool through the natural environment compares to 10.3% of the total emissions, and further afforestation of the community forest can contribute to an improvement of the total budget by 2.6%. The reduction aim of -15% until 2015 (compared with 2004), as set by the municipality itself, could be easily reached through better building insulation and the use of renewable energy sources. More ambitious aims, such as a 2000 W-society or CO 2 neutrality, however, will not be realised without major drawbacks in living standards

  13. NOx reduction using amine reclaimer wastes (ARW) generated in post combustion CO2 capture

    DEFF Research Database (Denmark)

    Botheju, Deshai; Glarborg, Peter; Tokheim, Lars-Andre

    2012-01-01

    Amine reclaimer wastes (ARW) generated in CO2 capture processes demand suitable disposal means. Such wastes contain remaining amine, NH3 and other degradation compounds. This study investigated the potential of using ARW as a NOx reducing agent, under laboratory conditions in a flow reactor....../NO ratios (waste product, together with its demonstrated NOx reduction capability and its calorific value contribution, makes it attractive as an additive...

  14. Potential Hydrogeomechanical Impacts of Geological CO2 Sequestration

    Science.gov (United States)

    McPherson, B. J.; Haerer, D.; Han, W.; Heath, J.; Morse, J.

    2006-12-01

    Long-term sequestration of anthropogenic "greenhouse gases" such as CO2 is a proposed approach to managing climate change. Deep brine reservoirs in sedimentary basins are possible sites for sequestration, given their ubiquitous nature. We used a mathematical sedimentary basin model, including coupling of multiphase CO2-groundwater flow and rock deformation, to evaluate residence times in possible brine reservoir storage sites, migration patterns and rates away from such sites, and effects of CO2 injection on fluid pressures and rock strain. Study areas include the Uinta and Paradox basins of Utah, the San Juan basin of New Mexico, and the Permian basin of west Texas. Regional-scale hydrologic and mechanical properties, including the presence of fracture zones, were calibrated using laboratory and field data. Our initial results suggest that, in general, long-term (~100 years or more) sequestration in deep brine reservoirs is possible, if guided by robust structural and hydrologic data. However, specific processes must be addressed to characterize and minimize risks. In addition to CO2 migration from target sequestration reservoirs into other reservoirs or to the land surface, another environmental issue is displacement of brines into freshwater aquifers. We evaluated the potential for such unintended aquifer contamination by displacement of brines out of adjacent sealing layers such as marine shales. Results suggest that sustained injection of CO2 may incur significant brine displacement out of adjacent sealing layers, depending on the injection history, initial brine composition, and hydrologic properties of both reservoirs and seals. Model simulations also suggest that as injection-induced overpressures migrate, effective stresses may follow this migration under some conditions, as will associated rock strain. Such "strain migration" may lead to induced or reactivated fractures or faults, but can be controlled through reservoir engineering.

  15. Performance analysis of photocatalytic CO2 reduction in optical fiber monolith reactor with multiple inverse lights

    International Nuclear Information System (INIS)

    Yuan, Kai; Yang, Lijun; Du, Xiaoze; Yang, Yongping

    2014-01-01

    Highlights: • A new optical fiber monolith reactor model for CO 2 reduction was developed. • Methanol concentration versus fiber location and operation parameters was obtained. • Reaction efficiency increases by 31.1% due to the four fibers and inverse layout. • With increasing space of fiber and channel center, methanol concentration increases. • Methanol concentration increases as the vapor ratio and light intensity increase. - Abstract: Photocatalytic CO 2 reduction seems potential to mitigate greenhouse gas emissions and produce renewable energy. A new model of photocatalytic CO 2 reduction in optical fiber monolith reactor with multiple inverse lights was developed in this study to improve the conversion of CO 2 to CH 3 OH. The new light distribution equation was derived, by which the light distribution was modeled and analyzed. The variations of CH 3 OH concentration with the fiber location and operation parameters were obtained by means of numerical simulation. The results show that the outlet CH 3 OH concentration is 31.1% higher than the previous model, which is attributed to the four fibers and inverse layout. With the increase of the distance between the fiber and the monolith center, the average CH 3 OH concentration increases. The average CH 3 OH concentration also rises as the light input and water vapor percentage increase, but declines with increasing the inlet velocity. The maximum conversion rate and quantum efficiency in the model are 0.235 μmol g −1 h −1 and 0.0177% respectively, both higher than previous internally illuminated monolith reactor (0.16 μmol g −1 h −1 and 0.012%). The optical fiber monolith reactor layout with multiple inverse lights is recommended in the design of photocatalytic reactor of CO 2 reduction

  16. Energy-related CO_2 emission in European Union agriculture: Driving forces and possibilities for reduction

    International Nuclear Information System (INIS)

    Li, Tianxiang; Baležentis, Tomas; Makutėnienė, Daiva; Streimikiene, Dalia; Kriščiukaitienė, Irena

    2016-01-01

    behind declines in CO_2 emission. According to the SBM, the lowest carbon shadow prices are observed in France, Finland, Sweden, Denmark, the Netherlands, Poland, and Belgium. These countries thus have the highest potential for reduction in CO_2 emission. The results imply that measures to increase energy efficiency are a more effective means to reduce CO_2 emissions than are changes in the fuel-mix.

  17. Simultaneous Reduction of CO 2 and Splitting of H 2 O by a Single Immobilized Cobalt Phthalocyanine Electrocatalyst

    KAUST Repository

    Morlanés, Natalia

    2016-04-12

    Perfluorinated cobalt phthalocyanine (CoFPc) immobilized on carbon electrodes was found to electrocatalyze the reduction of CO2 selectively to CO in an aqueous solution. The conversion of CO2 became apparent at -0.5 V vs RHE, and the Faradaic efficiency for the CO production reached as high as 93% at -0.8 V vs RHE. Highly stable electrolysis of CO2/H2O into CO/O2 was achieved for 12 h by applying the same catalyst as the cathode for CO2 reduction and the anode for water oxidation. This result indicates the highly robust nature of the CoFPc at wide range of potentials from -0.9 V to +2.2 V vs RHE, demonstrating the potential bipolar electrolytic system for CO2/H2O electrolysis, using the single-site molecular CoFPc-based electrocatalyst, which is simple, inexpensive, robust, and efficient. © 2016 American Chemical Society.

  18. What is a fair CO2 tax increase? On fair emission reductions in the transport sector

    International Nuclear Information System (INIS)

    Hammar, Henrik; Jagers, Sverker C.

    2007-01-01

    We examine how individual preferences for fair reductions of carbon dioxide (CO 2 ) emissions affect the support for increases in the CO 2 tax on gasoline and diesel. We assume that people not only care about their own material welfare, but also have preferences for fairness in policy design, and we explore the implications using original data from a mail questionnaire sent to a representative sample of the Swedish population. The main result is that fairness in policy design does matter. Those respondents who adhere to a fairness principle tend to be relatively more positive to increases in the CO 2 tax. One possible explanation for this result is that there is a relatively high degree of reciprocity regarding the origin of emissions and the fairness regarding who should bear the burden of CO 2 reductions. Via a split sample analysis, we also find that the relative importance of fairness principles is dependent upon whether one uses a car often or not. This sheds light on the potential goal conflict between the importance of fairness principles and self-interest in the form of a need for private car transportation. (author)

  19. A supply chain optimization framework for CO2 emission reduction: Case of the Netherlands

    OpenAIRE

    Kalyanarengan Ravi, N.; Zondervan, E.; van Sint Annaland, M.; Fransoo, J.C.; Grievink, J.; Claus, T.; Herrmann, F.; Manitz, M.; Rose, O.

    2016-01-01

    A major challenge for the industrial deployment of a CO2 emission reduction methodology is to reduce the overall cost and the integration of all the nodes in the supply chain for CO2 emission reduction. In this work, we develop a mixed integer linear optimization model that selects appropriate sources, capture process, transportation network and CO2 storage sites and optimize for a minimum overall cost. Initially, we screen the sources and storage options available in the Netherlands at diffe...

  20. Membraneless laminar flow cell for electrocatalytic CO2 reduction with liquid product separation

    International Nuclear Information System (INIS)

    Monroe, Morgan M; Lobaccaro, Peter; Lum, Yanwei; Ager, Joel W

    2017-01-01

    The production of liquid fuel products via electrochemical reduction of CO 2 is a potential path to produce sustainable fuels. However, to be practical, a separation strategy is required to isolate the fuel-containing electrolyte produced at the cathode from the anode and also prevent the oxidation products (i.e. O 2 ) from reaching the cathode. Ion-conducting membranes have been applied in CO 2 reduction reactors to achieve this separation, but they represent an efficiency loss and can be permeable to some product species. An alternative membraneless approach is developed here to maintain product separation through the use of a laminar flow cell. Computational modelling shows that near-unity separation efficiencies are possible at current densities achievable now with metal cathodes via optimization of the spacing between the electrodes and the electrolyte flow rate. Laminar flow reactor prototypes were fabricated with a range of channel widths by 3D printing. CO 2 reduction to formic acid on Sn electrodes was used as the liquid product forming reaction, and the separation efficiency for the dissolved product was evaluated with high performance liquid chromatography. Trends in product separation efficiency with channel width and flow rate were in qualitative agreement with the model, but the separation efficiency was lower, with a maximum value of 90% achieved. (paper)

  1. The application of CFD modelling to support the reduction of CO2 emissions in cement industry

    International Nuclear Information System (INIS)

    Mikulčić, Hrvoje; Vujanović, Milan; Fidaros, Dimitris K.; Priesching, Peter; Minić, Ivica; Tatschl, Reinhard; Duić, Neven; Stefanović, Gordana

    2012-01-01

    The cement industry is one of the leading producers of anthropogenic greenhouse gases, of which CO 2 is the most significant. Recently, researchers have invested a considerable amount of time studying ways to improve energy consumption and pollutant formation in the overall cement manufacturing process. One idea involves dividing the calcination and clinkering processes into two separate furnaces. The calcination process is performed in a calciner while the clinkering process takes place in a rotary kiln. As this is new technology in the cement manufacturing process, calciners are still in the research and development phase. The purpose of this paper is to demonstrate the potential of CFD to support the design and optimization of calciners, whose use appears to be essential in reduction of CO 2 emission during cement production. The mathematical model of the calcination process was developed, validated and implemented into a commercial CFD code, which was then used for the analysis. From the results obtained by these simulations, researchers will gain an in-depth understanding of all thermo-chemical reactions in a calciner. This understanding can be used to optimize the calciner's geometry, to make production more efficient, to lower pollutant formation and to subsequently reduce greenhouse gas emissions. -- Highlights: ► The potential of CO 2 emissions reduction, by using a cement calciner was presented. ► When a cement calciner is used, CO 2 emissions reduction of 3–4% can be achieved. ► The calcination model was developed, validated, and then used for the analysis. ► Shown method can be applied for investigation and optimization of cement calciners.

  2. A supply chain optimization framework for CO2 emission reduction : Case of the Netherlands

    NARCIS (Netherlands)

    Kalyanarengan Ravi, N.; Zondervan, E.; van Sint Annaland, M.; Fransoo, J.C.; Grievink, J.; Claus, T.; Herrmann, F.; Manitz, M.; Rose, O.

    2016-01-01

    A major challenge for the industrial deployment of a CO2 emission reduction methodology is to reduce the overall cost and the integration of all the nodes in the supply chain for CO2 emission reduction. In this work, we develop a mixed integer linear optimization model that selects appropriate

  3. Reduction of CO2 by nickel (II) macrocycle catalyst at HMDE

    Indian Academy of Sciences (India)

    Unknown

    CO is the major product in the gaseous phase and. HCOOH the sole product formed in the solution phase. Keywords. Nickel (II) azamacrocycle; electrocatalytic reduction of CO2; electrochemical reduction. 1. Introduction. Electrochemical processes for the conversion of carbon dioxide (CO2) to organic substances have ...

  4. Achieving CO2 reductions in Colombia: Effects of carbon taxes and abatement targets

    International Nuclear Information System (INIS)

    Calderón, Silvia; Alvarez, Andrés Camilo; Loboguerrero, Ana María; Arango, Santiago; Calvin, Katherine; Kober, Tom; Daenzer, Kathryn; Fisher-Vanden, Karen

    2016-01-01

    In this paper we investigate CO 2 emission scenarios for Colombia and the effects of implementing carbon taxes and abatement targets on the energy system. By comparing baseline and policy scenario results from two integrated assessment partial equilibrium models TIAM-ECN and GCAM and two general equilibrium models Phoenix and MEG4C, we provide an indication of future developments and dynamics in the Colombian energy system. Currently, the carbon intensity of the energy system in Colombia is low compared to other countries in Latin America. However, this trend may change given the projected rapid growth of the economy and the potential increase in the use of carbon-based technologies. Climate policy in Colombia is under development and has yet to consider economic instruments such as taxes and abatement targets. This paper shows how taxes or abatement targets can achieve significant CO 2 reductions in Colombia. Though abatement may be achieved through different pathways, taxes and targets promote the entry of cleaner energy sources into the market and reduce final energy demand through energy efficiency improvements and other demand-side responses. The electric power sector plays an important role in achieving CO 2 emission reductions in Colombia, through the increase of hydropower, the introduction of wind technologies, and the deployment of biomass, coal and natural gas with CO 2 capture and storage (CCS). Uncertainty over the prevailing mitigation pathway reinforces the importance of climate policy to guide sectors toward low-carbon technologies. This paper also assesses the economy-wide implications of mitigation policies such as potential losses in GDP and consumption. An assessment of the legal, institutional, social and environmental barriers to economy-wide mitigation policies is critical yet beyond the scope of this paper. - Highlights: • Four energy and economy-wide models under carbon mitigation scenarios are compared. • Baseline results show that CO

  5. Cocatalysts in Semiconductor-based Photocatalytic CO2 Reduction: Achievements, Challenges, and Opportunities.

    Science.gov (United States)

    Ran, Jingrun; Jaroniec, Mietek; Qiao, Shi-Zhang

    2018-02-01

    Ever-increasing fossil-fuel combustion along with massive CO 2 emissions has aroused a global energy crisis and climate change. Photocatalytic CO 2 reduction represents a promising strategy for clean, cost-effective, and environmentally friendly conversion of CO 2 into hydrocarbon fuels by utilizing solar energy. This strategy combines the reductive half-reaction of CO 2 conversion with an oxidative half reaction, e.g., H 2 O oxidation, to create a carbon-neutral cycle, presenting a viable solution to global energy and environmental problems. There are three pivotal processes in photocatalytic CO 2 conversion: (i) solar-light absorption, (ii) charge separation/migration, and (iii) catalytic CO 2 reduction and H 2 O oxidation. While significant progress is made in optimizing the first two processes, much less research is conducted toward enhancing the efficiency of the third step, which requires the presence of cocatalysts. In general, cocatalysts play four important roles: (i) boosting charge separation/transfer, (ii) improving the activity and selectivity of CO 2 reduction, (iii) enhancing the stability of photocatalysts, and (iv) suppressing side or back reactions. Herein, for the first time, all the developed CO 2 -reduction cocatalysts for semiconductor-based photocatalytic CO 2 conversion are summarized, and their functions and mechanisms are discussed. Finally, perspectives in this emerging area are provided. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Role of nuclear energy in CO2 emissions reduction

    International Nuclear Information System (INIS)

    Schaefer, H.

    1995-01-01

    Between 1675 and 1992 worldwide primary energy consumption has been multiplied by about 100 and has reached about 11 billions of tons of equivalent weight of coal, while human population has been multiplied by 8 and will probably reach 9 billions in 2030. The increase of atmospheric CO 2 production due to fossil fuel burn up will become a critical pollution and climatic problem which can be significantly reduced by a more widely use of nuclear energy in replacement of primary energies. However, perspectives of nuclear energy depend principally on the safety improvements of nuclear plants and on the solutions found to solve the management of radioactive waste. Renewable energies sources such as photovoltaic plants, wind engines, hydraulic plants have not yet been used at a large scale because they require large surfaces for their installation. To avoid any monolithic solution to solve the energy and environmental problems, a combination of renewable and nuclear energies seems to be a good compromise. For instance, the conception of a safety non-refueling nuclear reactor with an overheating hybrid system combining solar and fossil fuel energies should be conceivable. (J.S.)

  7. Economics show CO2 EOR potential in central Kansas

    Science.gov (United States)

    Dubois, M.K.; Byrnes, A.P.; Pancake, R.E.; Willhite, G.P.; Schoeling, L.G.

    2000-01-01

    Carbon dioxide (CO2) enhanced oil recovery (EOR) may be the key to recovering hundreds of millions of bbl of trapped oil from the mature fields in central Kansas. Preliminary economic analysis indicates that CO2 EOR should provide an internal rate of return (IRR) greater than 20%, before income tax, assuming oil sells for \\$20/bbl, CO2 costs \\$1/Mcf, and gross utilization is 10 Mcf of CO2/bbl of oil recovered. If the CO2 cost is reduced to \\$0.75/Mcf, an oil price of $17/bbl yields an IRR of 20%. Reservoir and economic modeling indicates that IRR is most sensitive to oil price and CO2 cost. A project requires a minimum recovery of 1,500 net bbl/acre (about 1 million net bbl/1-mile section) under a best-case scenario. Less important variables to the economics are capital costs and non-CO2 related lease operating expenses.

  8. trans-(Cl)-[Ru(5,5'-diamide-2,2'-bipyridine)(CO)2 Cl2 ]: Synthesis, Structure, and Photocatalytic CO2 Reduction Activity.

    Science.gov (United States)

    Kuramochi, Yusuke; Fukaya, Kyohei; Yoshida, Makoto; Ishida, Hitoshi

    2015-07-06

    A series of trans-(Cl)-[Ru(L)(CO)2 Cl2 ]-type complexes, in which the ligands L are 2,2'-bipyridyl derivatives with amide groups at the 5,5'-positions, are synthesized. The C-connected amide group bound to the bipyridyl ligand through the carbonyl carbon atom is twisted with respect to the bipyridyl plane, whereas the N-connected amide group is in the plane. DFT calculations reveal that the twisted structure of the C-connected amide group raises the level of the LUMO, which results in a negative shift of the first reduction potential (Ep ) of the ruthenium complex. The catalytic abilities for CO2 reduction are evaluated in photoreactions (λ>400 nm) with the ruthenium complexes (the catalyst), [Ru(bpy)3 ](2+) (bpy=2,2'-bipyridine; the photosensitizer), and 1-benzyl-1,4-dihydronicotinamide (the electron donor) in CO2 -saturated N,N-dimethylacetamide/water. The logarithm of the turnover frequency increases by shifting Ep a negative value until it reaches the reduction potential of the photosensitizer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Twin defects engineered Pd cocatalyst on C3N4 nanosheets for enhanced photocatalytic performance in CO2 reduction reaction

    Science.gov (United States)

    Lang, Qingqing; Hu, Wenli; Zhou, Penghui; Huang, Tianlong; Zhong, Shuxian; Yang, Lining; Chen, Jianrong; Bai, Song

    2017-12-01

    Photocatalytic conversion of CO2 to value-added chemicals, a potential route to addressing the depletion of fossil fuels and anthropogenic climate change, is greatly limited by the low-efficient semiconductor photocatalyst. The integration of cocatalyst with light-harvesting semiconductor is a promising approach to enhancing the photocatalytic performance in CO2 reduction reaction. The enhancement is greatly determined by the catalytic active sites on the surface of cocatalyst. Herein, we demonstrate that the photocatalytic performance in the CO2 reduction reaction is greatly promoted by twin defects engineered Pd cocatalyst. In this work, Pd nanoicosahedrons with twin defects were in situ grown on C3N4 nanosheets, which effectively improve the photocatalytic performance in reduction of CO2 to CO and CH4 in comparison with Pd nanotetrahedrons without twin defects. It is proposed that the twin boundary (TB) terminations on the surface of Pd cocatalysts are highly catalytic active sites for CO2 reduction reaction. Based on the proposed mechanism, the photocatalytic activity and selectivity in CO2 reduction were further advanced through reducing the size of Pd icosahedral cocatalyst resulted from the increased surface density of TB terminations. The defect engineering on the surface of cocatalyst represents a novel route in realizing high-performance photocatalytic applications.

  10. The improvement of CO2 emission reduction policies based on system dynamics method in traditional industrial region with large CO2 emission

    International Nuclear Information System (INIS)

    Li, Fujia; Dong, Suocheng; Li, Zehong; Li, Yu; Li, Shantong; Wan, Yongkun

    2012-01-01

    Some traditional industrial regions are characterized by high industrial proportion and large CO 2 emission. They are facing dual pressures of maintaining economic growth and largely reducing CO 2 emission. From the perspective of study of typological region, taking the typical traditional industrial region—Liaoning Province of China as a case, this study establishes a system dynamics model named EECP and dynamically simulates CO 2 emission trends under different conditions. Simulation results indicate, compared to the condition without CO 2 emission reduction policies, CO 2 emission intensity under the condition of implementing CO 2 emission reduction policies of “Twelfth Five-Year Plan” is decreased by 11% from 2009 to 2030, but the economic cost is high, making the policies implementation faces resistance. Then some improved policies are offered and proved by EECP model that they can reduce CO 2 emission intensity after 2021 and decrease the negative influence to GDP, realizing the improvement objects of reducing CO 2 emission and simultaneously keeping a higher economy growth speed. The improved policies can provide reference for making and improving CO 2 emission reduction policies in other traditional industrial regions with large CO 2 emission. Simultaneously, EECP model can provide decision-makers with reference and help for similar study of energy policy. - Highlights: ► We build EECP model for CO 2 emission reduction study in traditional industry region. ► By the model, we simulate CO 2 emission trend and improve emission reduction policy. ► By improvement, both CO 2 emission intensity and economic cost can be largely reduced. ► Besides CO 2 emission is reduced effectively, higher GDP increment speed is kept. ► EECP model can be widely used for making and improving regional energy policies.

  11. Controlled electropolymerisation of a carbazole-functionalised iron porphyrin electrocatalyst for CO2 reduction

    DEFF Research Database (Denmark)

    Hu, Xinming; Salmi, Zakaria; Lillethorup, Mie

    2016-01-01

    Using a one-step electropolymerisation procedure, CO2 absorbing microporous carbazole-functionalised films of iron porphyrins are prepared in a controlled manner. The electrocatalytic reduction of CO2 for these films is investigated to elucidate their efficiency and the origin of their ultimate...

  12. Opportunities and challenges in the electrocatalysis of CO2 and CO reduction using bifunctional surfaces

    DEFF Research Database (Denmark)

    Jovanov, Zarko; Hansen, Heine A.; Varela Gasque, Ana Sofia

    2016-01-01

    Electrolysis could enable the large-scale conversion of CO2 to fuels and small molecules. This perspective discusses the state-of-the-art understanding of CO2 and CO reduction electrocatalysis and provides an overview of the most promising approaches undertaken thus far. We set to explore "bifunc...

  13. CO2 reduction: is increasing the diesel share the way to go?

    NARCIS (Netherlands)

    Rijkeboer, R.C.; Havenith, C.; Baarbe, H.L.

    1998-01-01

    Different scenarios have been compared for the future reduction of CO2-emission under real-world driving conditions. A significant shift towards diesel appears hardly to benefit the CO2 but would carry a real NOx penalty. Introduction of DI petrol engines and a shift towards gaseous fuels for s.i.

  14. A Review of Hazardous Chemical Species Associated with CO2 Capturefrom Coal-Fired Power Plants and Their Potential Fate in CO2 GeologicStorage

    Energy Technology Data Exchange (ETDEWEB)

    Apps, J.A.

    2006-02-23

    Conventional coal-burning power plants are major contributors of excess CO2 to the atmospheric inventory. Because such plants are stationary, they are particularly amenable to CO2 capture and disposal by deep injection into confined geologic formations. However, the energy penalty for CO2 separation and compression is steep, and could lead to a 30-40 percent reduction in useable power output. Integrated gas combined cycle (IGCC) plants are thermodynamically more efficient, i.e.,produce less CO2 for a given power output, and are more suitable for CO2 capture. Therefore, if CO2 capture and deep subsurface disposal were to be considered seriously, the preferred approach would be to build replacement IGCC plants with integrated CO2 capture, rather than retrofit existing conventional plants. Coal contains minor quantities of sulfur and nitrogen compounds, which are of concern, as their release into the atmosphere leads to the formation of urban ozone and acid rain, the destruction of stratospheric ozone, and global warming. Coal also contains many trace elements that are potentially hazardous to human health and the environment. During CO2 separation and capture, these constituents could inadvertently contaminate the separated CO2 and be co-injected. The concentrations and speciation of the co-injected contaminants would differ markedly, depending on whether CO2 is captured during the operation of a conventional or an IGCC plant, and the specific nature of the plant design and CO2 separation technology. However, regardless of plant design or separation procedures, most of the hazardous constituents effectively partition into the solid waste residue. This would lead to an approximately two order of magnitude reduction in contaminant concentration compared with that present in the coal. Potential exceptions are Hg in conventional plants, and Hg and possibly Cd, Mo and Pb in IGCC plants. CO2 capture and injection disposal could afford an opportunity to deliberately capture

  15. Reduction of emissions and geological storage of CO2. Innovation an industrial stakes

    International Nuclear Information System (INIS)

    Mandil, C.; Podkanski, J.; Socolow, R.; Dron, D.; Reiner, D.; Horrocks, P.; Fernandez Ruiz, P.; Dechamps, P.; Stromberg, L.; Wright, I.; Gazeau, J.C.; Wiederkehr, P.; Morcheoine, A.; Vesseron, P.; Feron, P.; Feraud, A.; Torp, N.T.; Christensen, N.P.; Le Thiez, P.; Czernichowski, I.; Hartman, J.; Roulet, C.; Roberts, J.; Zakkour, P.; Von Goerne, G.; Armand, R.; Allinson, G.; Segalen, L.; Gires, J.M.; Metz, B.; Brillet, B.

    2005-01-01

    An international symposium on the reduction of emissions and geological storage of CO 2 was held in Paris from 15 to 16 September 2005. The event, jointly organized by IFP, ADEME and BRGM, brought together over 400 people from more than 25 countries. It was an opportunity to review the international stakes related to global warming and also to debate ways of reducing CO 2 emissions, taking examples from the energy and transport sectors. The last day was dedicated to technological advances in the capture and geological storage of CO 2 and their regulatory and economic implications. This document gathers the available transparencies and talks presented during the colloquium: Opening address by F. Loos, French Minister-delegate for Industry; Session I - Greenhouse gas emissions: the international stakes. Outlook for global CO 2 emissions. The global and regional scenarios: Alternative scenarios for energy use and CO 2 emissions until 2050 by C. Mandil and J. Podkanski (IEA), The stabilization of CO 2 emissions in the coming 50 years by R. Socolow (Princeton University). Evolution of the international context: the stakes and 'factor 4' issues: Costs of climate impacts and ways towards 'factor 4' by D. Dron (ENS Mines de Paris), CO 2 emissions reduction policy: the situation in the United States by D. Reiner (MIT/Cambridge University), Post-Kyoto scenarios by P. Horrocks (European Commission), Possibilities for R and D in CO 2 capture and storage in the future FP7 program by P. Fernandez Ruiz and P. Dechamps (European Commission). Session II - CO 2 emission reductions in the energy and transport sectors. Reducing CO 2 emissions during the production and conversion of fossil energies (fixed installations): Combined cycles using hydrogen by G. Haupt (Siemens), CO 2 emission reductions in the oil and gas industry by I. Wright (BP). Reducing CO 2 emissions in the transport sector: Sustainable transport systems by P. Wiederkehr (EST International), The prospects for reducing

  16. Emissions of CO2 from road freight transport in London: Trends and policies for long run reductions

    International Nuclear Information System (INIS)

    Zanni, Alberto M.; Bristow, Abigail L.

    2010-01-01

    Freight transport has been receiving increasing attention in both literature and practice following the growing recognition of its importance in urban transport planning. This paper analyses historical and projected road freight CO 2 emissions in the city of London and explores the potential mitigation effect of a set of freight transport policies and logistics solutions. Findings indicate a range of policies with potential to reduce emissions in the period up to 2050. However, this reduction would appear to only be capable of partly counterbalancing the projected increase in freight traffic. More profound behavioural measures therefore appear to be necessary for London's CO 2 emissions reduction targets to be met.

  17. Steering levies on the purchase of new cars for the reduction of CO2 emissions

    International Nuclear Information System (INIS)

    Haan, P. de; Mueller, M.; Peters, A.; Hauser, A.

    2007-12-01

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at the background, mechanisms and prognoses for the reduction of CO 2 emissions of new cars. This report focuses on policy measures - specifically the collection of budget-neutral so-called 'feebates' - that aim to influence the behaviour of buyers of new cars as a means of enhancing energy efficiency and reducing CO 2 emissions. Both the European Union and Switzerland are pursuing a three-pillar strategy in which agreements with manufacturers and importers (pillar 1) are supplemented by the provision of more detailed information for customers in the form of energy labels for new vehicles as well as catalogues listing levels of fuel consumption (pillar 2). Pillar 3 concerns measures aimed at influencing car buying behaviour, generally based on the use of the energy label for new vehicles in order to realise the existing potentials for reducing CO 2 emissions. The report takes a look at Switzerland's car market, buying behaviour, information on efficient vehicles, acceptance factors and incentive schemes. The findings of the study are presented and commented on.

  18. Light-induced cation exchange for copper sulfide based CO2 reduction.

    Science.gov (United States)

    Manzi, Aurora; Simon, Thomas; Sonnleitner, Clemens; Döblinger, Markus; Wyrwich, Regina; Stern, Omar; Stolarczyk, Jacek K; Feldmann, Jochen

    2015-11-11

    Copper(I)-based catalysts, such as Cu2S, are considered to be very promising materials for photocatalytic CO2 reduction. A common synthesis route for Cu2S via cation exchange from CdS nanocrystals requires Cu(I) precursors, organic solvents, and neutral atmosphere, but these conditions are not compatible with in situ applications in photocatalysis. Here we propose a novel cation exchange reaction that takes advantage of the reducing potential of photoexcited electrons in the conduction band of CdS and proceeds with Cu(II) precursors in an aqueous environment and under aerobic conditions. We show that the synthesized Cu2S photocatalyst can be efficiently used for the reduction of CO2 to carbon monoxide and methane, achieving formation rates of 3.02 and 0.13 μmol h(-1) g(-1), respectively, and suppressing competing water reduction. The process opens new pathways for the preparation of new efficient photocatalysts from readily available nanostructured templates.

  19. Assessing the potential long-term increase of oceanic fossil fuel CO2 uptake due to CO2-calcification feedback

    Directory of Open Access Journals (Sweden)

    T. M. Lenton

    2007-07-01

    Full Text Available Plankton manipulation experiments exhibit a wide range of sensitivities of biogenic calcification to simulated anthropogenic acidification of the ocean, with the "lab rat" of planktic calcifiers, Emiliania huxleyi apparently not representative of calcification generally. We assess the implications of this observational uncertainty by creating an ensemble of realizations of an Earth system model that encapsulates a comparable range of uncertainty in calcification response to ocean acidification. We predict that a substantial reduction in marine carbonate production is possible in the future, with enhanced ocean CO2 sequestration across the model ensemble driving a 4–13% reduction in the year 3000 atmospheric fossil fuel CO2 burden. Concurrent changes in ocean circulation and surface temperatures in the model contribute about one third to the increase in CO2 uptake. We find that uncertainty in the predicted strength of CO2-calcification feedback seems to be dominated by the assumption as to which species of calcifier contribute most to carbonate production in the open ocean.

  20. Novel, Regenerable Microlith Catalytic Reactor for CO2 Reduction via Bosch Process, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Precision Combustion, Inc. (PCI) proposes to develop an extremely compact, lightweight and regenerable MicrolithREG catalytic CO2 reduction reactor, capable of...

  1. Electrochemical reduction of CO2 to CO over Zn in propylene carbonate/tetrabutylammonium perchlorate

    Science.gov (United States)

    Shen, Feng-xia; Shi, Jin; Chen, Tian-you; Shi, Feng; Li, Qing-yuan; Zhen, Jian-zheng; Li, Yun-fei; Dai, Yong-nian; Yang, Bin; Qu, Tao

    2018-02-01

    Developing low cost and high efficient electrode for carbon dioxide (CO2) reduction in organic media is essential for practical application. Zn is a cheap metal and has high catalytic effects on CO2 reduction to carbon monoxide (CO) in aqueous solution. However, little attention has been given to investigate the performance of Zn in organic media for CO2 reduction. In present work, we have conducted CO2 reduction in propylene carbonate/tetrabutylammonium perchlorate on Zn due to that propylene carbonate is a widely used industrial absorber, and tetrabutylammonium perchlorate is a commonly used organic supporting electrolyte. In addition, because electrochemical reduction of CO2 to CO naturally produces H2O, we have discussed water effects on CO2 reduction in propylene carbonate/tetrabutylammonium perchlorate+6.8 wt % H2O. Our experiment results reveal that the faradaic efficiency for CO formation reaches to 83%, and the current density remains stable at 6.72 mA/cm2 at voltage -2.3 V for 4 h. Interestingly, Zn presents higher catalytic activity than Ag, and slightly lower than Au. X-ray photoelectron spectroscopy results confirm that no poisonous species is formed and absorbed on the cathode, which is an important advantage in practical application.

  2. Carbon dioxide sequestration by mineral carbonation. Feasibility of enhanced natural weathering as a CO2 emission reduction technology

    International Nuclear Information System (INIS)

    Huijgen, W.J.J.

    2007-01-01

    A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept behind mineral CO2 sequestration is the mimicking of natural weathering processes in which calcium or magnesium containing minerals react with gaseous CO2 and form solid calcium or magnesium carbonates. Potential advantages of mineral CO2 sequestration compared to, e.g., geological CO2 storage include (1) the permanent and inherently safe sequestration of CO2, due to the thermodynamic stability of the carbonate product formed and (2) the vast potential sequestration capacity, because of the widespread and abundant occurrence of suitable feedstock. In addition, carbonation is an exothermic process, which potentially limits the overall energy consumption and costs of CO2 emission reduction. However, weathering processes are slow, with timescales at natural conditions of thousands to millions of years. For industrial implementation, a reduction of the reaction time to the order of minutes has to be achieved by developing alternative process routes. The aim of this thesis is an investigation of the technical, energetic, and economic feasibility of CO2 sequestration by mineral carbonation. In Chapter 1 the literature published on CO2 sequestration by mineral carbonation is reviewed. Among the potentially suitable mineral feedstock for mineral CO2 sequestration, Ca-silicates, more particularly wollastonite (CaSiO3), a mineral ore, and steel slag, an industrial alkaline solid residue, are selected for further research. Alkaline Ca-rich residues seem particularly promising, since these materials are inexpensive and available near large industrial point sources of CO2. In addition, residues tend to react relatively rapidly with CO2 due to their (geo)chemical instability. Various process routes have been proposed for mineral carbonation, which often include a pre-treatment of the solid feedstock (e.g., size reduction and

  3. Progress and Perspective of Electrocatalytic CO2 Reduction for Renewable Carbonaceous Fuels and Chemicals.

    Science.gov (United States)

    Zhang, Wenjun; Hu, Yi; Ma, Lianbo; Zhu, Guoyin; Wang, Yanrong; Xue, Xiaolan; Chen, Renpeng; Yang, Songyuan; Jin, Zhong

    2018-01-01

    The worldwide unrestrained emission of carbon dioxide (CO 2 ) has caused serious environmental pollution and climate change issues. For the sustainable development of human civilization, it is very desirable to convert CO 2 to renewable fuels through clean and economical chemical processes. Recently, electrocatalytic CO 2 conversion is regarded as a prospective pathway for the recycling of carbon resource and the generation of sustainable fuels. In this review, recent research advances in electrocatalytic CO 2 reduction are summarized from both experimental and theoretical aspects. The referred electrocatalysts are divided into different classes, including metal-organic complexes, metals, metal alloys, inorganic metal compounds and carbon-based metal-free nanomaterials. Moreover, the selective formation processes of different reductive products, such as formic acid/formate (HCOOH/HCOO - ), monoxide carbon (CO), formaldehyde (HCHO), methane (CH 4 ), ethylene (C 2 H 4 ), methanol (CH 3 OH), ethanol (CH 3 CH 2 OH), etc. are introduced in detail, respectively. Owing to the limited energy efficiency, unmanageable selectivity, low stability, and indeterminate mechanisms of electrocatalytic CO 2 reduction, there are still many tough challenges need to be addressed. In view of this, the current research trends to overcome these obstacles in CO 2 electroreduction field are summarized. We expect that this review will provide new insights into the further technique development and practical applications of CO 2 electroreduction.

  4. Australia's CO2 geological storage potential and matching of emission sources to potential sinks

    International Nuclear Information System (INIS)

    Bradshaw, J.; Bradshaw, B.E.; Wilson, P.; Spencer, L.; Allinson, G.; Nguyen, V.

    2004-01-01

    Within the GEODISC program of the Australian Petroleum Cooperative Research Centre (APCRC), Geoscience Australia (GA) and the University of New South Wales (UNSW) have completed an analysis of the potential for the geological storage of CO 2 . The geological analysis assessed over 100 potential environmentally sustainable sites for CO 2 injection (ESSCIs) by applying a deterministic risk assessment based on the five factors of: storage capacity, injectivity potential, site details, containment and natural resources. Utilising a risked storage capacity suggests that at a regional scale Australia has a CO 2 storage potential in excess of 1600 years of current annual total net emissions. Whilst this estimate does give an idea of the enormous magnitude of the geological storage potential of CO 2 in Australia, it does not account for various factors that are evident in source to sink matching. If preferences due to source to sink matching are incorporated, and an assumption is made that some economic imperative will apply to encourage geological storage of CO 2 , then a more realistic analysis can be derived. In such a case, Australia may have the potential to store a maximum of 25% of our total annual net emissions, or approximately 100-115 Mt CO 2 per year. (author)

  5. Potential gains from CO2 trading in the EU

    DEFF Research Database (Denmark)

    Svendsen, Gert Tinggaard; Vesterdal, Morten

    2003-01-01

    A new Green Paper from the European Commission on emissions trading foresees the setting-up of a CO2 trading system within the EU for the energy sector. Because any such international environmental agreement is self-enforcing, the participants must have an economic net gain from joining the propo......A new Green Paper from the European Commission on emissions trading foresees the setting-up of a CO2 trading system within the EU for the energy sector. Because any such international environmental agreement is self-enforcing, the participants must have an economic net gain from joining...... the proposed system. Our contribution is therefore to follow the Green Paper proposal and investigate whether member countries and the largest industrial boilers in the electricity sector actually will get significant net gains from CO2 trade in the European Union rather than undertaking domestic actions...... solely. We show, based on PRIMES model, that a full CO2 emission trading system between Annex B countries suggest overall cost savings in the order of 40 % compared to a situation with no trading at all between Member States. A tradable CO2 permit scheme with comprehensive coverage of emissions within...

  6. Organic reactions for the electrochemical and photochemical production of chemical fuels from CO2--The reduction chemistry of carboxylic acids and derivatives as bent CO2 surrogates.

    Science.gov (United States)

    Luca, Oana R; Fenwick, Aidan Q

    2015-11-01

    The present review covers organic transformations involved in the reduction of CO2 to chemical fuels. In particular, we focus on reactions of CO2 with organic molecules to yield carboxylic acid derivatives as a first step in CO2 reduction reaction sequences. These biomimetic initial steps create opportunities for tandem electrochemical/chemical reductions. We draw parallels between long-standing knowledge of CO2 reactivity from organic chemistry, organocatalysis, surface science and electrocatalysis. We point out some possible non-faradaic chemical reactions that may contribute to product distributions in the production of solar fuels from CO2. These reactions may be accelerated by thermal effects such as resistive heating and illumination. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Plasma for electrification of chemical industry : a case study on CO2 reduction

    NARCIS (Netherlands)

    Van Rooij, G.J.; Akse, H.N.; Bongers, W.A.; Van De Sanden, M.C.M.

    2018-01-01

    Significant growth of the share of (intermittent) renewable power in the chemical industry is imperative to meet increasingly stricter limits on CO2 exhaust that are being implemented within Europe. This paper aims to evaluate the potential of a plasma process that converts input CO2 into a pure

  8. Plasma for Electrification of Chemical Industry: a Case Study on CO2 Reduction

    NARCIS (Netherlands)

    van Rooij, G. J.; Akse, H.; Bongers, W.; van de Sanden, M. C. M.

    2018-01-01

    Significantly increasing the share of (intermittent) renewable power in the chemical industry is imperative to meet increasingly stricter limits on CO2 exhaust that are being implemented within Europe. This paper aims to evaluate the potential of a plasma process that converts input CO2 into a pure

  9. How can China reach its CO2 intensity reduction targets by 2020? A regional allocation based on equity and development

    International Nuclear Information System (INIS)

    Yi Wenjing; Zou Lele; Guo Jie; Wang Kai; Wei Yiming

    2011-01-01

    In late 2009, the Chinese government committed to cut its carbon dioxide emissions per unit of gross domestic product (GDP) by 40% to 45% of 2005 levels by 2020. This has raised the issue of how to allocate the CO 2 reduction target regionally to meet the national reduction target. To meet this objective, the following aspects may be taken into consideration: equity principles, 'common but differentiated responsibilities'; intensity reduction target fulfillment; and economic difference and reduction potential among provinces. This paper selects per capita GDP, accumulated fossil fuel related CO 2 emissions and energy consumption per unit of industrial added value as indicators for emission reduction capacity, responsibility and potential, respectively. Based on these three indicators, a comprehensive index is developed and an intensity allocation model constructed. As decision makers may have different preferences when allocating the reduction burden, we allocate different weights to the indicators, analyzing the results using cluster analysis. The following aspects may also be considered together with the national regional development strategy to determine how to share the burden: the reduction potential of various regions; implementation potential of the plans; and promotion of a highly efficient low carbon economic development model. - Research highlights: → We compiled a comprehensive index using per capita GDP, accumulated fossil fuel related CO 2 emissions and energy consumption per unit of industrial added value as indicators for emission reduction capacity, responsibility and potential, respectively. → National CO 2 intensity reduction target is allocated according to different index values of provinces. → Equity principles were taken into account when allocating the target.

  10. Reduction of CO2 emissions during cement clinker burning : Part 2 = Ein Beitrag zur Reduzierung der CO2-Emissionen beim Zementklinkerbrand; Teil 2

    NARCIS (Netherlands)

    Vogel, S.; Kolditz, K.; Beilmann, F.; Finger, F.A.; Ott-Reinhardt, D.; Kralisch, D.

    2013-01-01

    The aim of the research project entitled "New technology in cement production for reducing CO2 emissions" sponsored by the German Federal Environmental Foundation was to lower the CO2 emissions during clinker burning. A possible reduction, relative to an industrial example, of up to 21 % in the

  11. Reduction of CO2 emissions during cement clinker burning; part 1 = Ein Beitrag zur Reduzierung der CO2-Emissionen beim Zementklinkerbrand; Teil 1

    NARCIS (Netherlands)

    Vogel, S.; Kolditz, K.; Bellmann, F.; Ott-Reinhardt, D.; Kralisch, D.

    2013-01-01

    The aim of the research project entitled "New technology in cement production for reducing CO2 emissions" sponsored by the German Federal Environmental Foundation was to lower the CO2 emissions during clinker burning. A possible reduction, relative to an industrial example, of up to 21 % in the

  12. Prediction of the viscosity reduction due to dissolved CO2 of and an elementary approach in the supercritical CO2 assisted continuous particle production of a polyester resin

    NARCIS (Netherlands)

    Nalawade, Sameer P.; Nieborg, Vincent H. J.; Picchioni, Francesco; Janssen, L. P. B. M.

    2006-01-01

    The dissolution of CO2 in a polymer causes plasticization of the polymer and hence, its viscosity is reduced. A model based on the free volume theory has been used for a polyester resin, which shows a considerable reduction in the viscosity due to dissolved M. Therefore, superctitical CO2 has been

  13. Carbon Supported Engineering NiCo2O4 Hybrid Nanofibers with Enhanced Electrocatalytic Activity for Oxygen Reduction Reaction

    Directory of Open Access Journals (Sweden)

    Diab Hassan

    2016-09-01

    Full Text Available The design of cheap and efficient oxygen reduction reaction (ORR electrocatalysts is of a significant importance in sustainable and renewable energy technologies. Therefore, ORR catalysts with superb electrocatalytic activity and durability are becoming a necessity but still remain challenging. Herein, we report C/NiCo2O4 nanocomposite fibers fabricated by a straightforward electrospinning technique followed by a simple sintering process as a promising ORR electrocatalyst in alkaline condition. The mixed-valence oxide can offer numerous accessible active sites. In addition, the as-obtained C/NiCo2O4 hybrid reveals significantly remarkable electrocatalytic performance with a highly positive onset potential of 0.65 V, which is only 50 mV lower than that of commercially available Pt/C catalysts. The analyses indicate that C/NiCo2O4 catalyst can catalyze O2-molecules via direct four electron pathway in a similar behavior as commercial Pt/C catalysts dose. Compared to single NiCo2O4 and carbon free NiCo2O4, the C/NiCo2O4 hybrid displays higher ORR current and more positive half-wave potential. The incorporated carbon matrices are beneficial for fast electron transfer and can significantly impose an outstanding contribution to the electrocatalytic activity. Results indicate that the synthetic strategy hold a potential as efficient route to fabricate highly active nanostructures for practical use in energy technologies.

  14. Reduction of CO2 emission by INCAM model in Malaysia biomass power plants during the year 2016.

    Science.gov (United States)

    Amin, Nor Aishah Saidina; Talebian-Kiakalaieh, Amin

    2018-03-01

    As the world's second largest palm oil producer and exporter, Malaysia could capitalize on its oil palm biomass waste for power generation. The emission factors from this renewable energy source are far lower than that of fossil fuels. This study applies an integrated carbon accounting and mitigation (INCAM) model to calculate the amount of CO 2 emissions from two biomass thermal power plants. The CO 2 emissions released from biomass plants utilizing empty fruit bunch (EFB) and palm oil mill effluent (POME), as alternative fuels for powering steam and gas turbines, were determined using the INCAM model. Each section emitting CO 2 in the power plant, known as the carbon accounting center (CAC), was measured for its carbon profile (CP) and carbon index (CI). The carbon performance indicator (CPI) included electricity, fuel and water consumption, solid waste and waste-water generation. The carbon emission index (CEI) and carbon emission profile (CEP), based on the total monthly carbon production, were determined across the CPI. Various innovative strategies resulted in a 20%-90% reduction of CO 2 emissions. The implementation of reduction strategies significantly reduced the CO 2 emission levels. Based on the model, utilization of EFB and POME in the facilities could significantly reduce the CO 2 emissions and increase the potential for waste to energy initiatives. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Performance Limits of Photoelectrochemical CO2 Reduction Based on Known Electrocatalysts and the Case for Two-Electron Reduction Products

    DEFF Research Database (Denmark)

    Vesborg, Peter Christian Kjærgaard; Seger, Brian

    2016-01-01

    Solar-drivenreduction of CO2 to solar fuels as an alternative to H2 via water splitting is an intriguing proposition. We modelthe solar-to-fuel (STF) efficiencies using realistic parameters basedon recently reported CO2 reduction catalysts with a highperformance tandem photoabsorber structure. CO...... due to excessiveoverpotentials and poor selectivity. This work considers breakingup the multielectron reduction pathway into individually optimized,separate two-electron steps as a way forward....

  16. Potential Improvements of Supercritical Recompression CO2 Brayton Cycle Coupled with KALIMER-600 by Modifying Critical Point of CO2

    International Nuclear Information System (INIS)

    Jeong, Woo Seok; Lee, Jeong Ik; Jeong, Yong Hoon; No, Hee Cheon

    2010-01-01

    Most of the existing designs of a Sodium cooled Fast Reactor (SFR) have a Rankine cycle as an electric power generation cycle. This has the risk of a sodium water reaction. To prevent any hazards from a sodium water reaction, an indirect Brayton cycle using Supercritical Carbon dioxide (S-CO 2 ) as the working fluids for a SFR is an alternative approach to improve the current SFR design. The supercritical Brayton cycle is defined as a cycle with operating conditions above the critical point and the main compressor inlet condition located slightly above the critical point of working fluid. This is because the main advantage of the cycle comes from significantly decreased compressor work just above the critical point due to high density near boundary between supercritical state and subcritical state. For this reason, the minimum temperature and pressure of cycle are just above the CO 2 critical point. In other words, the critical point acts as a limitation of the lowest operating condition of the cycle. In general, lowering the minimum temperature of a thermodynamic cycle can increase the efficiency and the minimum temperature can be decreased by shifting the critical point of CO 2 as mixed with other gases. In this paper, potential enhancement of S-CO 2 cycle coupled with KALIMER-600, which has been developed at KAERI, was investigated using a developed cycle code with a gas mixture property program

  17. Optimal production resource reallocation for CO2 emissions reduction in manufacturing sectors

    OpenAIRE

    Fujii, Hidemichi; Managi, Shunsuke

    2015-01-01

    To mitigate the effects of climate change, countries worldwide are advancing technologies to reduce greenhouse gas emissions. This paper proposes and measures optimal production resource reallocation using data envelopment analysis. This research attempts to clarify the effect of optimal production resource reallocation on CO2 emissions reduction, focusing on regional and industrial characteristics. We use finance, energy, and CO2 emissions data from 13 industrial sectors in 39 countries from...

  18. Mineral Carbonation Potential of CO2 from Natural and Industrial-based Alkalinity Sources

    Science.gov (United States)

    Wilcox, J.; Kirchofer, A.

    2014-12-01

    Mineral carbonation is a Carbon Capture and Storage (CSS) technology where gaseous CO2 is reacted with alkaline materials (such as silicate minerals and alkaline industrial wastes) and converted into stable and environmentally benign carbonate minerals (Metz et al., 2005). Here, we present a holistic, transparent life cycle assessment model of aqueous mineral carbonation built using a hybrid process model and economic input-output life cycle assessment approach. We compared the energy efficiency and the net CO2 storage potential of various mineral carbonation processes based on different feedstock material and process schemes on a consistent basis by determining the energy and material balance of each implementation (Kirchofer et al., 2011). In particular, we evaluated the net CO2 storage potential of aqueous mineral carbonation for serpentine, olivine, cement kiln dust, fly ash, and steel slag across a range of reaction conditions and process parameters. A preliminary systematic investigation of the tradeoffs inherent in mineral carbonation processes was conducted and guidelines for the optimization of the life-cycle energy efficiency are provided. The life-cycle assessment of aqueous mineral carbonation suggests that a variety of alkalinity sources and process configurations are capable of net CO2 reductions. The maximum carbonation efficiency, defined as mass percent of CO2 mitigated per CO2 input, was 83% for CKD at ambient temperature and pressure conditions. In order of decreasing efficiency, the maximum carbonation efficiencies for the other alkalinity sources investigated were: olivine, 66%; SS, 64%; FA, 36%; and serpentine, 13%. For natural alkalinity sources, availability is estimated based on U.S. production rates of a) lime (18 Mt/yr) or b) sand and gravel (760 Mt/yr) (USGS, 2011). The low estimate assumes the maximum sequestration efficiency of the alkalinity source obtained in the current work and the high estimate assumes a sequestration efficiency

  19. Incentives for subcontractors to adopt CO2 emission reporting and reduction techniques

    International Nuclear Information System (INIS)

    Scholtens, Bert; Kleinsmann, Renske

    2011-01-01

    We investigate the incentives for subcontractors (couriers) of a transport and logistics company to report about their CO 2 emissions and to implement CO 2 reducing technologies. Furthermore, we try to find out whether these incentives differ between British and Dutch couriers. We find that several incentives play a significant role. Subcontractors in the Netherlands predominantly are extrinsically motivated to engage in CO 2 reporting and reduction techniques. This is because they are mainly driven by regulatory compliance, energy costs and implementation costs. In contrast, British subcontractors are much more intrinsically motivated to comply. They are predominantly driven by energy costs, environmental awareness, relationship building and reputation building. The contractor will have to account for these differences in making its policies work. - Research highlights: → We investigate incentives for couriers to report CO 2 emissions and to implement CO 2 reduction techniques. → We compare couriers in the Netherlands and the United Kingdom. → Several incentives are significant for the adoption of CO 2 reporting and reduction measures. → There are significant differences in the sensitivity for incentives in the Netherlands and the UK.

  20. Subsurface oxide plays a critical role in CO_2 activation by Cu(111) surfaces to form chemisorbed CO_2 , the first step in reduction of CO_2

    OpenAIRE

    Favaro, Marco; Xiao, Hai; Cheng, Tao; Goddard, William A.; Yano, Junko; Crumlin, Ethan J.

    2017-01-01

    A national priority is to convert CO_2 into high-value chemical products such as liquid fuels. Because current electrocatalysts are not adequate, we aim to discover new catalysts by obtaining a detailed understanding of the initial steps of CO_2 electroreduction on copper surfaces, the best current catalysts. Using ambient pressure X-ray photoelectron spectroscopy interpreted with quantum mechanical prediction of the structures and free energies, we show that the presence of a thin suboxide s...

  1. Subsurface oxide plays a critical role in CO2 activation by Cu(111) surfaces to form chemisorbed CO2, the first step in reduction of CO2

    OpenAIRE

    Favaro, M; Xiao, H; Cheng, T; Goddard, WA; Crumlin, EJ

    2017-01-01

    A national priority is to convert CO2 into high-value chemical products such as liquid fuels. Because current electrocatalysts are not adequate, we aim to discover new catalysts by obtaining a detailed understanding of the initial steps of CO2 electroreduction on copper surfaces, the best current catalysts. Using ambient pressure X-ray photoelectron spectroscopy interpreted with quantum mechanical prediction of the structures and free energies, we show that the presence of a thin suboxide str...

  2. Strategi for CO2-reduktion i den individuelle varmeforsyning: Strategy for CO2 reduction in the individual heat supply

    OpenAIRE

    Schjerling, Tina Gliese

    2008-01-01

    The project is made in cooperation with Lolland municipality, which has set a series of ambitious goals in relation to reducing the CO2 emissions in the municipality. One of the challenges faced by the municipality in this connection is to achieve a cleaner heat supply. The collective heat supply is almost 100% CO2-neutral, as the district heating plants primarily use CO2-neutral fuel. However, there are a great number of households outside the collective heat supply, which are heated by mean...

  3. Single site porphyrine-like structures advantages over metals for selective electrochemical CO2 reduction

    DEFF Research Database (Denmark)

    Bagger, Alexander; Ju, Wen; Varela, Ana Sofia

    2017-01-01

    Currently, no catalysts are completely selective for the electrochemical CO2 Reduction Reaction (CO2RR). Based on trends in density functional theory calculations of reaction intermediates we find that the single metal site in a porphyrine-like structure has a simple advantage of limiting...... the competing Hydrogen Evolution Reaction (HER). The single metal site in a porphyrine-like structure requires an ontop site binding of hydrogen, compared to the hollow site binding of hydrogen on a metal catalyst surface. The difference in binding site structure gives a fundamental energy-shift in the scaling...... relation of ∼0.3eV between the COOH* vs. H* intermediate (CO2RR vs. HER). As a result, porphyrine-like catalysts have the advantage over metal catalyst of suppressing HER and enhancing CO2RR selectivity....

  4. Estimation and reduction of CO2 emissions from crude oil distillation units

    International Nuclear Information System (INIS)

    Gadalla, M.; Olujic, Z.; Jobson, M.; Smith, R.

    2006-01-01

    Distillation systems are energy-intensive processes, and consequently contribute significantly to the greenhouse gases emissions (e.g. carbon dioxide (CO 2 ). A simple model for the estimation of CO 2 emissions associated with operation of heat-integrated distillation systems as encountered in refineries is introduced. In conjunction with a shortcut distillation model, this model has been used to optimize the process conditions of an existing crude oil atmospheric tower unit aiming at minimization of CO 2 emissions. Simulation results indicate that the total CO 2 emissions of the existing crude oil unit can be cut down by 22%, just by changing the process conditions accordingly, and that the gain in this respect can be doubled by integrating a gas turbine. In addition, emissions reduction is accompanied by substantial profit increase due to utility saving and/or export

  5. Rational Design of a Hierarchical Tin Dendrite Electrode for Efficient Electrochemical Reduction of CO2.

    Science.gov (United States)

    Won, Da Hye; Choi, Chang Hyuck; Chung, Jaehoon; Chung, Min Wook; Kim, Eun-Hee; Woo, Seong Ihl

    2015-09-21

    Catalysis is a key technology for the synthesis of renewable fuels through electrochemical reduction of CO2 . However, successful CO2 reduction still suffers from the lack of affordable catalyst design and understanding the factors governing catalysis. Herein, we demonstrate that the CO2 conversion selectivity on Sn (or SnOx /Sn) electrodes is correlated to the native oxygen content at the subsurface. Electrochemical analyses show that the reduced Sn electrode with abundant oxygen species effectively stabilizes a CO2 (.-) intermediate rather than the clean Sn surface, and consequently results in enhanced formate production in the CO2 reduction. Based on this design strategy, a hierarchical Sn dendrite electrode with high oxygen content, consisting of a multi-branched conifer-like structure with an enlarged surface area, was synthesized. The electrode exhibits a superior formate production rate (228.6 μmol h(-1)  cm(-2) ) at -1.36 VRHE without any considerable catalytic degradation over 18 h of operation. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Coupled Metal/Oxide Catalysts with Tunable Product Selectivity for Electrocatalytic CO2 Reduction.

    Science.gov (United States)

    Huo, Shengjuan; Weng, Zhe; Wu, Zishan; Zhong, Yiren; Wu, Yueshen; Fang, Jianhui; Wang, Hailiang

    2017-08-30

    One major challenge to the electrochemical conversion of CO 2 to useful fuels and chemical products is the lack of efficient catalysts that can selectively direct the reaction to one desirable product and avoid the other possible side products. Making use of strong metal/oxide interactions has recently been demonstrated to be effective in enhancing electrocatalysis in the liquid phase. Here, we report one of the first systematic studies on composition-dependent influences of metal/oxide interactions on electrocatalytic CO 2 reduction, utilizing Cu/SnO x heterostructured nanoparticles supported on carbon nanotubes (CNTs) as a model catalyst system. By adjusting the Cu/Sn ratio in the catalyst material structure, we can tune the products of the CO 2 electrocatalytic reduction reaction from hydrocarbon-favorable to CO-selective to formic acid-dominant. In the Cu-rich regime, SnO x dramatically alters the catalytic behavior of Cu. The Cu/SnO x -CNT catalyst containing 6.2% of SnO x converts CO 2 to CO with a high faradaic efficiency (FE) of 89% and a j CO of 11.3 mA·cm -2 at -0.99 V versus reversible hydrogen electrode, in stark contrast to the Cu-CNT catalyst on which ethylene and methane are the main products for CO 2 reduction. In the Sn-rich regime, Cu modifies the catalytic properties of SnO x . The Cu/SnO x -CNT catalyst containing 30.2% of SnO x reduces CO 2 to formic acid with an FE of 77% and a j HCOOH of 4.0 mA·cm -2 at -0.99 V, outperforming the SnO x -CNT catalyst which only converts CO 2 to formic acid in an FE of 48%.

  7. CO_2 emissions and energy intensity reduction allocation over provincial industrial sectors in China

    International Nuclear Information System (INIS)

    Wu, Jie; Zhu, Qingyuan; Liang, Liang

    2016-01-01

    Highlights: • DEA is used to evaluate the energy and environmental efficiency of 30 provincial industrial sector in China. • A new DEA-based model is proposed to allocate the CO_2 emissions and energy intensity reduction targets. • The context-dependent DEA is used to characterize the production plans. - Abstract: High energy consumption by the industry of developing countries has led to the problems of increasing emission of greenhouse gases (GHG) (primarily CO_2) and worsening energy shortages. To address these problems, many mitigation measures have been utilized. One major measure is to mandate fixed reductions of GHG emission and energy consumption. Therefore, it is important for each developing country to disaggregate their national reduction targets into targets for various geographical parts of the country. In this paper, we propose a DEA-based approach to allocate China’s national CO_2 emissions and energy intensity reduction targets over Chinese provincial industrial sectors. We firstly evaluate the energy and environmental efficiency of Chinese industry considering energy consumption and GHG emissions. Then, considering the necessity of mitigating GHG emission and energy consumption, we develop a context-dependent DEA technique which can better characterize the changeable production with reductions of CO_2 emission and energy intensity, to help allocate the national reduction targets over provincial industrial sectors. Our empirical study of 30 Chinese regions for the period 2005–2010 shows that the industry of China had poor energy and environmental efficiency. Considering three major geographical areas, eastern China’s industrial sector had the highest efficiency scores while in this aspect central and western China were similar to each other at a lower level. Our study shows that the most effective allocation of the national reduction target requires most of the 30 regional industrial to reduce CO_2 emission and energy intensity, while a

  8. Surface-reconstructed Cu Electrode via a Facile Electrochemical Anodization-Reduction Process for Low Overpotential CO 2 reduction

    KAUST Repository

    Min, Shixiong; Yang, Xiulin; Lu, Ang-Yu; Tseng, Chien-Chih; Hedhili, Mohamed N.; Lai, Zhiping; Li, Lain-Jong; Huang, Kuo-Wei

    2017-01-01

    A high-surface-area Cu electrode, fabricated by a simple electrochemical anodization-reduction method, exhibits high activity and selectivity for CO2 reduction at low overpotential in 0.1 M KHCO3 solution. A faradaic efficiency of 37% for HCOOH

  9. High-throughput synthesis of mixed-metal electrocatalysts for CO2 reduction

    International Nuclear Information System (INIS)

    He, Jingfu; Dettelbach, Kevan E.; Li, Tengfei; Salvatore, Danielle A.; Berlinguette, Curtis P.

    2017-01-01

    The utilization of CO 2 as a feedstock requires fundamental breakthroughs in catalyst design. The efficiencies and activities of pure metal electrodes towards the CO 2 reduction reaction are established, but the corresponding data on mixed-metal systems are not as well developed. In this study we show that the near-infrared driven decomposition (NIRDD) of solution-deposited films of metal salts and subsequent electrochemical reduction offers the unique opportunity to form an array of mixed-metal electrocatalyst coatings with excellent control of the metal stoichiometries. This synthetic method enabled us to develop an empirical structure-property correlation to help inform the development of optimized CO 2 catalyst compositions. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. An analysis of energy strategies for CO2 emission reduction in China. Case studies by MARKAL model

    International Nuclear Information System (INIS)

    Li Guangya

    1994-12-01

    The China's energy system has been analyzed by using the MARKAL model in this study and the time period is from the year 1990 to 2050. The MARKAL model is applied here to evaluate the cost effective energy strategies for CO 2 emission reduction in China. Firstly the Reference Energy System (RES) of China and its database were established, and the useful energy demand was projected on the basis of China's economic target and demographic forecasting. Four scenarios, BASE1-BASE4 were defined with different assumptions of crude oil and natural uranium availability. Analytical results show that without CO 2 emission constrains coal consumption will continue to hold a dominant position in primary energy supply, and CO 2 emissions in 2050 will be 9.55 BtCO 2 and 10.28 BtCO 2 with different natural uranium availability. Under the CO 2 emission constraints, nuclear and renewable energy will play important roles in CO 2 emission reduction, and feasible maximum CO 2 emission reduction estimated by this study is 3.16 BtCO 2 in 2050. The cumulative CO 2 emission from 1990 to 2050 will be 418.25 BtCO 2 and 429.16 BtCO 2 with different natural uranium availability. Total feasible maximum CO 2 emission reduction from 1990 to 2050 is 95.97 BtCO 2 . (author)

  11. Potential effects of emission taxes on CO2 emissions in OECD and LDC countries. Working paper

    International Nuclear Information System (INIS)

    Messner, S.; Strubegger, M.

    1990-12-01

    A set of existing optimization models representing the energy systems of the OECD and LDC countries (the LDC region covers all less developed countries excluding centrally planned economies) with a time horizon up to 2020 was applied to derive first-order estimates of the techno-economic potential for emission reduction. The driving force for the introduction of reduction measures was a scheme of taxes levied on the emissions of 6 relevant pollutants-including the greenhouse gases CO 2 and methane. The tax levels introduced are based on the taxes discussed by the Swedish government administration; they are the break-even point to test which measures are cost-effective and which emission levels can be reached at these costs. The regional models offer the choice between the following alternatives as response to increases in expenditures caused by emission taxes: (*) Reduction of final energy demand by supplying the requested services by other means (i.e., conservation). (*) Substitution of 'dirty' fuels by fuels entailing less pollution. (*) Introduction of 'clean' technologies for the same purposes (e.g., a combined cycle based on coal gasification is a much cleaner process for electricity generation from coal than conventional coal power plants). (*) For SO 2 and NO x emissions pollution reduction technologies (i.e., scrubbers and catalysts) can be added to existing technologies in order to reduce emissions. Alternative scenarios with emission taxes are compared to a base scenario without taxes related to pollutant emissions. The results indicate that an increase in CO 2 emissions in the OECD and LDC regions of 47% over the next 30 years in the base scenario would be changed into stabilization up to 2010 by measures induced by the tax levels introduced. Thereafter, however, energy consumption growth in the LDC area, in conjunction with the exhaustion of economically viable emission reduction measures, reverse this trend: CO 2 emissions start to increase again after

  12. CO2 Reduction Catalyzed by Nitrogenase: Pathways to Formate, Carbon Monoxide, and Methane.

    Science.gov (United States)

    Khadka, Nimesh; Dean, Dennis R; Smith, Dayle; Hoffman, Brian M; Raugei, Simone; Seefeldt, Lance C

    2016-09-06

    The reduction of N2 to NH3 by Mo-dependent nitrogenase at its active-site metal cluster FeMo-cofactor utilizes reductive elimination of Fe-bound hydrides with obligatory loss of H2 to activate the enzyme for binding/reduction of N2. Earlier work showed that wild-type nitrogenase and a nitrogenase with amino acid substitutions in the MoFe protein near FeMo-cofactor can catalytically reduce CO2 by two or eight electrons/protons to carbon monoxide (CO) and methane (CH4) at low rates. Here, it is demonstrated that nitrogenase preferentially reduces CO2 by two electrons/protons to formate (HCOO(-)) at rates >10 times higher than rates of CO2 reduction to CO and CH4. Quantum mechanical calculations on the doubly reduced FeMo-cofactor with a Fe-bound hydride and S-bound proton (E2(2H) state) favor a direct reaction of CO2 with the hydride ("direct hydride transfer" reaction pathway), with facile hydride transfer to CO2 yielding formate. In contrast, a significant barrier is observed for reaction of Fe-bound CO2 with the hydride ("associative" reaction pathway), which leads to CO and CH4. Remarkably, in the direct hydride transfer pathway, the Fe-H behaves as a hydridic hydrogen, whereas in the associative pathway it acts as a protic hydrogen. MoFe proteins with amino acid substitutions near FeMo-cofactor (α-70(Val→Ala), α-195(His→Gln)) are found to significantly alter the distribution of products between formate and CO/CH4.

  13. Energy efficiency and reduction of CO2 emissions from campsites management in a protected area.

    Science.gov (United States)

    Del Moretto, Deny; Branca, Teresa Annunziata; Colla, Valentina

    2018-06-02

    Campsites can be a pollution source, mainly due to the energy consumption. In addition, the green areas, thanks to the direct CO 2 sequestration and the shading, indirectly prevent the CO 2 emissions related to energy consumption. The methodology presented in this paper allowed assessing the annual CO 2 emissions directly related to the campsite management and the consequent environmental impact in campsite clusters in Tuscany. The software i-Tree Canopy was exploited, enabling to evaluate in terms of "canopy" the tonnes of CO 2 sequestered by the vegetation within each campsite. Energy and water consumptions from 2012 to 2015 were assessed for each campsite. As far as the distribution of sequestered CO 2 is concerned, the campsites ranking was in accordance to their size. According to the indicator "T-Tree" or canopy cover, a larger area of the canopy cover allows using less outdoor areas covered by trees for the sequestration of the remaining amount of pollutants. The analysis shows that the considered campsites, that are located in a highly naturalistic Park, present significant positive aspects both in terms of CO 2 emission reductions and of energy efficiency. However, significant margins of improvement are also possible and they were analysed in the paper. Copyright © 2018 Elsevier Ltd. All rights reserved.

  14. CO2 Conversion: The Potential of Porous–Organic Polymers (POPs) for the cycloaddition of CO2 and epoxides

    KAUST Repository

    Alkordi, Mohamed Helmi

    2016-03-30

    Novel porous organic polymers (POPs) have been synthesized using functionalized Cr and Co-salen complexes as molecular building blocks. The integration of metalosalen catalysts into the porous polymers backbone permits the successful utilization of the materials as solid-state catalysts for CO2-epoxide cycloadditions reactions with excellent catalytic performance under mild conditions of temperature and pressure. The catalyst proved to be fully recyclable and robust thus showing the potential of POPs as smart functional materials for the heterogenization of key catalytic elements.

  15. Low Overpotential and High Current CO2 Reduction with Surface Reconstructed Cu Foam Electrodess

    KAUST Repository

    Min, Shixiong; Yang, Xiulin; Lu, Ang-Yu; Tseng, Chien-Chih; Hedhili, Mohamed N.; Li, Lain-Jong; Huang, Kuo-Wei

    2016-01-01

    for large-scale fuel synthesis. Here we report an extremely high current density for CO2 reduction at low overpotential using a Cu foam electrode prepared by air-oxidation and subsequent electroreduction. Apart from possessing three-dimensional (3D) open

  16. Electrochemical reduction of CO2 on compositionally variant Au-Pt bimetallic thin films

    NARCIS (Netherlands)

    Ma, M.; Hansen, H.A.; Valenti, M.; Wang, Z.; Cao, A.; Dong, M.; Smith, W.A.

    2017-01-01

    The electrocatalytic reduction of CO2 on Au-Pt bimetallic catalysts with different compositions was evaluated, offering a platform for uncovering the correlation between the catalytic activity and the surface composition of bimetallic electrocatalysts. The Au-Pt alloy films were synthesized by a

  17. Nature and Distribution of Stable Subsurface Oxygen in Copper Electrodes During Electrochemical CO2 Reduction

    DEFF Research Database (Denmark)

    Cavalca, Filippo Carlo; Ferragut, Rafael; Aghion, Stefano

    2017-01-01

    Oxide-derived copper (OD-Cu) electrodes exhibit higher activity than pristine copper during the carbon dioxide reduction reaction (CO2RR) and higher selectivity towards ethylene. The presence of residual subsurface oxygen in OD-Cu has been proposed to be responsible for such improvements, although...

  18. Transition paths towards CO2 emission reduction in the steel industry

    NARCIS (Netherlands)

    Daniëls, Berend Wilhelm

    2002-01-01

    Radiative forcing, better known as the Greenhouse Effect, is probably the major 21st century environmental problem. Its probable cause is the anthropogenic emission of greenhouse gases, especially CO2. The Kyoto agreement enforces considerable reductions of the GHG emissions in 2010, with 6 to 8% of

  19. Potential effects of emission taxes on CO2 emissions in the OECD and LDCs

    International Nuclear Information System (INIS)

    Messner, S.; Strubegger, M.

    1991-01-01

    A set of existing optimization models, which represent the energy systems of the OECD and LDCs (less developed countries excluding centrally planned economies) with a time horizon to 2020, has been applied to derive first-order estimates of the techno-economic potential for emission reduction. The driving force for the introduction of reduction measures is a scheme of taxes levied on the emission of six pollutants, including the greenhouse gases CO 2 and methane. The tax levels introduced are based on taxes discussed by the Swedish government: they are the break-even point to test which measures are cost-effective and which emission levels can be reached at these costs. The regional models include the following alternatives: (i) reduction of final energy demand by supplying the requested services by other means (i.e., conservation); (ii) substitution of new fuels for polluting fuels; (iii) introduction of clean technologies for the same purposes; (iv) additions of pollution-reduction technologies. Alternative scenarios with emission taxes are compared with a base scenario without taxes related to pollutant emissions. The results indicate that an increase in CO 2 emissions in the OECD and LDC regions of 47% over the next 30 yr in the base scenario would be changed to stable levels to 2010 by tax-induced measures. Thereafter, energy-consumption growth in the LDCs reverses this trend. (author)

  20. Potential for CO2 sequestration and enhanced coalbed methane production in the Netherlands

    OpenAIRE

    Hamelinck, C.N.; Schreurs, H.; Faaij, A.P.C.; Ruijg, G.J.; Jansen, Daan; Pagnier, H.; Bergen, F. van; Wolf, K.-H.; Barzandji, O.; Bruining, H.

    2006-01-01

    This study investigated the technical and economic feasibility of using CO2 for the enhanced production of coal bed methane (ECBM) in the Netherlands. This concept could lead to both CO2 storage by adsorbing CO2 in deep coal layers that are not suitable for mining, as well as production of methane. For every two molecules of CO2 injected, roughly one molecule of methane is produced. The work included an investigation of the potential CBM reserves in the Dutch underground and the related CO2 s...

  1. Economic and game-theoretical analysis of CO2 reduction agreements

    International Nuclear Information System (INIS)

    Tahvonen, O.

    1994-01-01

    The possibility of climate change and suggestions to stabilize CO 2 emissions have led to several different fields of research in resource and environmental economics. These include: 1. Studies on country specific and global greenhouse gas abatement costs. 2. Studies on global and country specific adaptation costs. 3. Game-theoretical analysis of greenhouse gas reduction agreements. 4. Studies on the relationship between CO 2 accumulation and natural resource utilization. 5. Models of climate change and intertemporal efficiency and equity. 6. Studies on emissions taxes and emissions permit markets for greenhouse gas abatement. The aim of this project is to contribute to the economic literature in fields 3, and 4

  2. Uncertainty-averse TRANSCO planning for accommodating renewable energy in CO2 reduction environment

    DEFF Research Database (Denmark)

    Zhang, Chunyu; Ding, Yi; Wang, Qi

    2015-01-01

    , demand-side variations, market price volatility, and transmission configuration. Three objectives, i.e. social CO2 reduction benefit, energy purchase and network expansion cost and power delivery profit, are optimized simultaneously by a developed two-phase multi-objective particle swarm optimization......The concern of the environment and energy sustainability requests a crucial target of CO2 abatement and results in a relatively high penetration of renewable energy generation in the transmission system. For maintaining system reliability and security, the transmission company (TRANSCO) has to make...

  3. The global warming game - simulations of a CO2 reduction agreement

    International Nuclear Information System (INIS)

    Fankhauser, S.; Kverndokk, S.

    1992-06-01

    The paper analyses incentives for and the benefits of a possible international cooperation to reduce CO-2-emissions. The negotiations are modeled as a (static) reciprocal-externality-game in CO 2 -emissions between five world regions. CO 2 -emissions affect the players in two ways: First, each country's income depends (via energy inputs) on the amount of CO 2 emitted. On the other hand, emissions may cause future damage due to climate change. Without cooperation, each player maximizes its net benefits in setting marginal income equal to its marginal damage cost (Nash equilibrium). Under full cooperation marginal income equals the sum of the marginal damages (social optimum). The paper presents simulations of these two equilibria. Compared to the situation where no attention is paid to the greenhouse effect (the business as usual scenario), emission reductions under the Nash equilibrium can be interpreted as incentives for unilateral actions. According to the simulation results, this can only be expected from OECD countries. The results also imply that a socially optimal treaty, while clearly beneficial for the world in its entirety, may only be achieved if side payments are offered to at least China and the former Soviet Union, and probably the USA. The optimal global emission reductions in this study are on average lower than the reductions recommended by international conferences. 34 refs., 2 figs., 9 tabs

  4. Analyses on Cost Reduction and CO2 Mitigation by Penetration of Fuel Cells to Residential Houses

    Science.gov (United States)

    Aki, Hirohisa; Yamamoto, Shigeo; Kondoh, Junji; Murata, Akinobu; Ishii, Itaru; Maeda, Tetsuhiko

    This paper presents analyses on the penetration of polymer electrolyte fuel cells (PEFC) into a group of 10 residential houses and its effects of CO2 emission mitigation and consumers’ cost reduction in next 30 years. The price is considered to be reduced as the penetration progress which is expected to begin in near future. An experimental curve is assumed to express the decrease of the price. Installation of energy interchange systems which involve electricity, gas and hydrogen between a house which has a FC and contiguous houses is assumed to utilize both electricity and heat more efficiently, and to avoid start-stop operation of fuel processor (reformer) as much as possible. A multi-objective model which considers CO2 mitigation and consumers’ cost reduction is constructed and provided a Pareto optimum solution. A solution which simultaneously realizes both CO2 mitigation and consumers’ cost reduction appeared in the Pareto optimum solution. Strategies to reduce CO2 emission and consumers’ cost are suggested from the results of the analyses. The analyses also revealed that the energy interchange systems are effective especially in the early stage of the penetration.

  5. Low Overpotential and High Current CO2 Reduction with Surface Reconstructed Cu Foam Electrodess

    KAUST Repository

    Min, Shixiong

    2016-06-23

    While recent reports have demonstrated that oxide-derived Cu-based electrodes exhibit high selectivity for CO2 reduction at low overpotential, the low catalytic current density (<2 mA/cm2 at -0.45 V vs. RHE) still largely limits its applications for large-scale fuel synthesis. Here we report an extremely high current density for CO2 reduction at low overpotential using a Cu foam electrode prepared by air-oxidation and subsequent electroreduction. Apart from possessing three-dimensional (3D) open frameworks, the resulting Cu foam electrodes prepared at higher temperatures exhibit enhanced electrochemically active surface area and distinct surface structures. In particular, the Cu foam electrode prepared at 500 °C exhibits an extremely high geometric current density of ~9.4 mA/cm2 in CO2-satrurated 0.1 M KHCO3 aqueous solution and achieving ~39% CO and ~23% HCOOH Faradaic efficiencies at -0.45 V vs. RHE. The high activity and significant selectivity enhancement are attributable to the formation of abundant grain-boundary supported active sites and preferable (100) and (111) facets as a result of reconstruction of Cu surface facets. This work demonstrates that the structural integration of Cu foam with open 3D frameworks and the favorable surface structures is a promising strategy to develop an advanced Cu electrocatalyst that can operate at high current density and low overpotential for CO2 reduction.

  6. CO2 emissions mitigation potential of solar home systems under clean development mechanism in India

    International Nuclear Information System (INIS)

    Purohit, Pallav

    2009-01-01

    The Government of India has taken several initiatives for promotion of solar energy systems in the country during the last two decades. A variety of policy measures have been adopted which include provision of financial and fiscal incentives to the potential users of solar energy systems however, only 0.4 million solar home systems (SHSs) have been installed so far that is far below their respective potential. One of the major barriers is the high costs of investments in these systems. The clean development mechanism (CDM) of the Kyoto Protocol provides industrialized (Annex-I) countries with an incentive to invest in emission reduction projects in developing (non-Annex-I) countries to achieve a reduction in carbon dioxide (CO 2 ) emissions at lowest cost that also promotes sustainable development in the host country. SHSs could be of interest under the CDM because they directly displace greenhouse gas (GHG) emissions while contributing to sustainable rural development, if developed correctly. In this study an attempt has been made to estimate the CO 2 mitigation potential of SHSs under CDM in India.

  7. Recent Advances in Transition-Metal-Mediated Electrocatalytic CO2 Reduction: From Homogeneous to Heterogeneous Systems

    Directory of Open Access Journals (Sweden)

    Da-Ming Feng

    2017-12-01

    Full Text Available Global climate change and increasing demands for clean energy have brought intensive interest in the search for proper electrocatalysts in order to reduce carbon dioxide (CO2 to higher value carbon products such as hydrocarbons. Recently, transition-metal-centered molecules or organic frameworks have been reported to show outstanding electrocatalytic activity in the liquid phase. Their d-orbital electrons are believed to be one of the key factors to capture and convert CO2 molecules to value-added low-carbon fuels. In this review, recent advances in electrocatalytic CO2 reduction have been summarized based on the targeted products, ranging from homogeneous reactions to heterogeneous ones. Their advantages and fallbacks have been pointed out and the existing challenges, especially with respect to the practical and industrial application are addressed.

  8. Recent Advances in Transition-Metal-Mediated Electrocatalytic CO2 Reduction: From Homogeneous to Heterogeneous Systems

    KAUST Repository

    Feng, Da-Ming

    2017-12-01

    Global climate change and increasing demands for clean energy have brought intensive interest in the search for proper electrocatalysts in order to reduce carbon dioxide (CO2) to higher value carbon products such as hydrocarbons. Recently, transition-metal-centered molecules or organic frameworks have been reported to show outstanding electrocatalytic activity in the liquid phase. Their d-orbital electrons are believed to be one of the key factors to capture and convert CO2 molecules to value-added low-carbon fuels. In this review, recent advances in electrocatalytic CO2 reduction have been summarized based on the targeted products, ranging from homogeneous reactions to heterogeneous ones. Their advantages and fallbacks have been pointed out and the existing challenges, especially with respect to the practical and industrial application are addressed.

  9. Modelling the aqueous and nonaqueous interfaces for CO2 electro-reduction over Sn catalysts

    Science.gov (United States)

    Sheng, Tian; Sun, Shi-Gang

    2018-01-01

    In CO2 electroreduction, Sn catalysts with a high overpotential for hydrogen evolution reaction and a high selectivity towards formic acid formation are very attractive. Many efforts have been made for improving the catalytic performance and for understanding the mechanisms. In electrochemistry, the role of solvents for surface reactions was deserved to be investigated, in particular for some nonaqueous solvents. Here, we have modeled the aqueous (water) and nonaqueous (acetonitrile and dichloromethane) for investigation of CO2 electroreduction on Sn surface, by constrained ab initio molecular dynamics simulations and thermodynamic integrations, including a number of explicit solvent molecules in computational models. It was found that CO2 reduction is initiated from formate formation and solvents, in particular, water can effectively facilitate the reaction.

  10. The potential of geological storage of CO2 in Austria: a techno-economic assessment

    Science.gov (United States)

    Brüstle, Anna Katharina; Welkenhuysen, Kris; Bottig, Magdalena; Piessens, Kris; Ramirez, Andrea; Swenner, Rudy

    2014-05-01

    economic uncertainties. Results indicate a significant potential for CCS in Austria and a very high probability for any CO2 storage activity. The assessment of the average practical capacity of the whole country is 120Mt at 15€/tCO2 of storage budget, while the average matched national capacity is 40Mt. Concerning the individual reservoirs, reservoir development probabilities generally lie between 20 and 30%. These numbers served as basis for a reservoir exploration ranking. Compared to current emissions, total storage capacity is at the low end, which is likely the main technical limiting factor for CCS deployment in Austria. Also, current policy seems not in favour of CCS. Storage capacity is however high enough to provide a significant contribution to the reduction of CO2 emissions in the country, in the order of a few million tonnes per year. Opportunities to combine CO2 geological storage and geothermal energy seem promising, but require additional evaluation. Welkenhuysen, K., Ramirez, A., Swennen, R. & Piessens, K., 2013. Ranking potential CO2 storage reservoirs: an exploration priority list for Belgium. International Journal of Greenhouse Gas Control, 17, p. 431-449

  11. Mode selection of China's urban heating and its potential for reducing energy consumption and CO2 emission

    International Nuclear Information System (INIS)

    Chen, Xia; Wang, Li; Tong, Lige; Sun, Shufeng; Yue, Xianfang; Yin, Shaowu; Zheng, Lifang

    2014-01-01

    China's carbon dioxide (CO 2 ) emission ranks the highest in the world. CO 2 emission from urban central heating, which has an average annual growth rate of 10.3%, is responsible for 4.4% of China's total CO 2 emission. The current policy for improving urban central heating focuses on replacing coal with natural gas. This paper analyzes the existing situation and problems pertaining to urban heating, and evaluates the potential for reducing energy consumption and CO 2 emission by heat pump heating. The results show that the current policy of replacing coal with natural gas for urban central heating decreases energy consumption and CO 2 emission by 16.6% and 63.5%, respectively. On the other hand, replacing coal-based urban central heating with heat pump heating is capable of decreasing energy consumption and CO 2 emission by 57.6% and 81.4%, respectively. Replacing both urban central and decentralized heating with heat pump heating can lead to 67.7% and 85.8% reduction in energy consumption and CO 2 emission, respectively. The decreases in CO 2 emission will account for 24.5% of China's target to reduce total CO 2 emission by 2020. - Highlights: • Existing situation and problems of urban heating in China. • Feasibility of heat pump heating in China. • Potential of energy saving and emission reduction for heat pump heating. • China should adjust urban heating strategy. • Replacing urban central heating and decentralized heating with heat pump heating

  12. Topotactic reduction of YBaCo2O5 and LaBaCo2O5: square-planar Co(I) in an extended oxide.

    Science.gov (United States)

    Seddon, James; Suard, Emmanuelle; Hayward, Michael A

    2010-03-03

    The low-temperature reduction of YBaCo(2)O(5) and LaBaCo(2)O(5) with NaH to form YBaCo(2)O(4.5) and YBaCo(2)O(4.25), respectively, demonstrates that the structures of anion-deficient materials formed by such topotactic reductions can be directed by the ordering and identity of the A-site cations. YBaCo(2)O(4.5) adopts a structure consisting of a corner-shared network of square-based pyramidal CoO(5) and distorted tetrahedral CoO(4) units. The structure of LaBaCoO(4.25) is more complex, consisting of an array of square-based pyramidal CoO(5), distorted tetrahedral CoO(4), and square planar CoO(4) units. Magnetic susceptibility and variable-temperature neutron diffraction data reveal that YBaCo(2)O(4.5) adopts a G-type antiferromagnetically ordered structure below T(N) approximately 280 K. LaBaCo(2)O(4.25) also adopts antiferromagnetic order (T(N) approximately 325 K) with ordered moments consistent with the presence of square-planar, low-spin, s = 0, Co(I) centers. A detailed analysis reveals that the different anion vacancy ordered structures adopted by the two REBaCo(2)O(5-x) phases are directed by the relative sizes and ordering of the La(3+) and Y(3+) cations. This suggests that ordered arrangements of A-cations can be used to direct the anion vacancy order in topotactically reduced phases, allowing the preparation of novel metal-oxygen networks containing unusual transition metal coordination environments.

  13. CO2 Reduction Catalyzed by Nitrogenase: Pathways to Formate, Carbon Monoxide, and Methane

    OpenAIRE

    Khadka, Nimesh; Dean, Dennis R.; Smith, Dayle; Hoffman, Brian M.; Raugei, Simone; Seefeldt, Lance C.

    2016-01-01

    The reduction of N2 to NH3 by Mo-dependent nitrogenase at its active-site metal cluster FeMo-cofactor utilizes reductive elimination (re) of Fe-bound hydrides with obligatory loss of H2 to activate the enzyme for binding/reduction of N2. Earlier work showed that wild type nitrogenase and a nitrogenase having amino acid substitutions in the MoFe protein near FeMo-cofactor can catalytically reduce CO2 by 2 or 8 electrons/protons to carbon monoxide (CO) and methane (CH4) at low rates. Here, it i...

  14. Detection of CO2•- in the Electrochemical Reduction of Carbon Dioxide in N,N-Dimethylformamide by Scanning Electrochemical Microscopy.

    Science.gov (United States)

    Kai, Tianhan; Zhou, Min; Duan, Zhiyao; Henkelman, Graeme A; Bard, Allen J

    2017-12-27

    The electrocatalytic reduction of CO 2 has been studied extensively and produces a number of products. The initial reaction in the CO 2 reduction is often taken to be the 1e formation of the radical anion, CO 2 •- . However, the electrochemical detection and characterization of CO 2 •- is challenging because of the short lifetime of CO 2 •- , which can dimerize and react with proton donors and even mild oxidants. Here, we report the generation and quantitative determination of CO 2 •- in N,N-dimethylformamide (DMF) with the tip generation/substrate collection (TG/SC) mode of scanning electrochemical microscopy (SECM). CO 2 was reduced at a hemisphere-shaped Hg/Pt ultramicroelectrode (UME) or a Hg/Au film UME, which were utilized as the SECM tips. The CO 2 •- produced can either dimerize to form oxalate within the nanogap between SECM tip and substrate or collected at SECM substrate (e.g., an Au UME). The collection efficiency (CE) for CO 2 •- depends on the distance (d) between the tip and substrate. The dimerization rate (6.0 × 10 8 M -1 s -1 ) and half-life (10 ns) of CO 2 •- can be evaluated by fitting the collection efficiency vs distance curve. The dimerized species of CO 2 •- , oxalate, can also be determined quantitatively. Furthermore, the formal potential (E 0 ') and heterogeneous rate constant (k 0 ) for CO 2 reduction were determined with different quaternary ammonium electrolytes. The significant difference in k 0 is due to a tunneling effect caused by the adsorption of the electrolytes on the electrode surface at negative potentials.

  15. Energy in the Netherlands. Optimized pathways to CO2 reduction in the Dutch context

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-09-15

    This document reports the findings of research undertaken by the Energy Forum NL (EFNL) which consists of companies active in different parts of the energy sector. The group strives for a more long-term, stable energy policy and investment climate in the Netherlands, one that will help realize overall climate ambitions. This report is part of the group's contribution to the energy debate in the Netherlands; it lays out a fact-based, objective analysis of the potential energy mix if one assumes a continued focus on carbon abatement. In this report, the Energy Forum NL provides pathways that show how the Netherlands can best contribute to the EU target of 80% CO2e emission reduction by 2050 compared to 1990. They particularly focus on the goal for the next 20 years: reducing CO2e emissions by 40% by 2030 compared to 1990. The Forum selected 40% as a midway target for 80% in 2050; this falls within the EU ambition of 40%-44% in 2030.1 The period beyond 2030, which is much more uncertain, is modeled in less detail. However, the Forum took care to not let the choice of any pathway during 2010-2030 lock a pathway after 2030 in or out. A 'least cost' approach, which works across sectors, is used to reduce emissions. In a 'least cost' approach, all emission reduction measures are ranked on costs and implemented progressively (starting from the cheapest) until the targeted abatement level is reached. In addition, a few developing technologies are implemented even if they are more expensive than alternatives. This choice prevents technology lock-in, ensures a more versatile, resilient energy system and provides a reasonable starting position for the period post-2030. The report assumes a pan-European approach for the power sector, which is the key sector in the Emissions Trading Scheme (ETS); in this case, Dutch abatement options 'compete' with those in other EU countries. For the other sectors it uses a national approach. Non-cost factors

  16. A Polarizable and Transferable PHAST CO 2 Potential for Materials Simulation

    KAUST Repository

    Mullen, Ashley L.

    2013-12-10

    Reliable PHAST (Potentials with High Accuracy Speed and Transferability) intermolecular potential energy functions for CO2 have been developed from first principles for use in heterogeneous systems, including one with explicit polarization. The intermolecular potentials have been expressed in a transferable form and parametrized from nearly exact electronic structure calculations. Models with and without explicit many-body polarization effects, known to be important in simulation of interfacial processes, are constructed. The models have been validated on pressure-density isotherms of bulk CO 2 and adsorption in three metal-organic framework (MOF) materials. The present models appear to offer advantages over high quality fluid/liquid state potentials in describing CO2 interactions in interfacial environments where sorbates adopt orientations not commonly explored in bulk fluids. Thus, the nonpolar CO2-PHAST and polarizable CO 2-PHAST* potentials are recommended for materials/interfacial simulations. © 2013 American Chemical Society.

  17. One strategy for estimating the potential soil carbon storage due to CO2 fertilization

    International Nuclear Information System (INIS)

    Harrison, K.G.; Bonani, G.

    1994-01-01

    Soil radiocarbon measurements can be used to estimate soil carbon turnover rates and inventories. A labile component of soil carbon has the potential to respond to perturbations such as CO 2 fertilization, changing climate, and changing land use. Soil carbon has influenced past and present atmospheric CO 2 levels and will influence future levels. A model is used to calculate the amount of additional carbon stored in soil because of CO 2 fertilization

  18. The public perspective of carbon capture and storage for CO2 emission reductions in China

    International Nuclear Information System (INIS)

    Duan Hongxia

    2010-01-01

    To explore public awareness of carbon capture and storage (CCS), attitudes towards the use of CCS and the determinants of CCS acceptance in China, a study was conducted in July 2009 based on face-to-face interviews with participants across the country. The result showed that the awareness of CCS was low among the surveyed public in China, compared to other clean energy technologies. Respondents indicated a slightly supportive attitude towards the use of CCS as an alternative technology to CO 2 emission reductions. The regression model revealed that in addition to CCS knowledge, respondents' understanding of the characteristics of CCS, such as the maturity of the technology, risks, capability of CO2 emission reductions, and CCS policy were all significant factors in predicting the acceptance of CCS. The findings suggest that integrating public education and communication into CCS development policy would be an effective strategy to overcome the barrier of low public acceptance.

  19. Nitrogen-based catalysts for the electrochemical reduction of CO2 to CO.

    Science.gov (United States)

    Tornow, Claire E; Thorson, Michael R; Ma, Sichao; Gewirth, Andrew A; Kenis, Paul J A

    2012-12-05

    The synthesis and application of carbon-supported, nitrogen-based organometallic silver catalysts for the reduction of CO(2) is studied using an electrochemical flow reactor. Their performance toward the selective formation of CO is similar to the performance achieved when using Ag as the catalyst, but comparatively at much lower silver loading. Faradaic efficiencies of the organometallic catalyst are higher than 90%, which are comparable to those of Ag. Furthermore, with the addition of an amine ligand to Ag/C, the partial current density for CO increases significantly, suggesting a possible co-catalyst mechanism. Additional improvements in activity and selectivity may be achieved as greater insight is obtained on the mechanism of CO(2) reduction and on how these complexes assemble on the carbon support.

  20. Integrated Reservoir Modeling of CO2-EOR Performance and Storage Potential in the Farnsworth Field Unit, Texas.

    Science.gov (United States)

    Ampomah, W.; Balch, R. S.; Cather, M.; Dai, Z.

    2017-12-01

    We present a performance assessment methodology and storage potential for CO2 enhanced oil recovery (EOR) in partially depleted reservoirs. A three dimensional heterogeneous reservoir model was developed based on geological, geophysics and engineering data from Farnsworth field Unit (FWU). The model aided in improved characterization of prominent rock properties within the Pennsylvanian aged Morrow sandstone reservoir. Seismic attributes illuminated previously unknown faults and structural elements within the field. A laboratory fluid analysis was tuned to an equation of state and subsequently used to predict the thermodynamic minimum miscible pressure (MMP). Datasets including net-to-gross ratio, volume of shale, permeability, and burial history were used to model initial fault transmissibility based on Sperivick model. An improved history match of primary and secondary recovery was performed to set the basis for a CO2 flood study. The performance of the current CO2 miscible flood patterns was subsequently calibrated to historical production and injection data. Several prediction models were constructed to study the effect of recycling, addition of wells and /or new patterns, water alternating gas (WAG) cycles and optimum amount of CO2 purchase on incremental oil production and CO2 storage in the FWU. The history matching study successfully validated the presence of the previously undetected faults within FWU that were seen in the seismic survey. The analysis of the various prediction scenarios showed that recycling a high percentage of produced gas, addition of new wells and a gradual reduction in CO2 purchase after several years of operation would be the best approach to ensure a high percentage of recoverable incremental oil and sequestration of anthropogenic CO2 within the Morrow reservoir. Larger percentage of stored CO2 were dissolved in residual oil and less amount existed as supercritical free CO2. The geomechanical analysis on the caprock proved to an

  1. CO2 emission reduction strategy and roles of nuclear energy in Japan

    International Nuclear Information System (INIS)

    Sato, Osamu; Shimoda, Makoto; Takematsu, Kenji; Tadokoro, Yoshihiro

    1999-03-01

    An analysis was made on the potential and cost of reducing carbon dioxide (CO 2 ) emissions from Japan's long-term energy systems by using the MARKAL model, developed in the Energy Technology Systems Analysis Programme (ETSAP) of International Energy Agency (IEA). Assuming future growths of GDP, the demand for energy services was estimated for the analytical time horizon 1990-2050. Assumptions were made also on prices and availability of fossil fuels, and on availability of nuclear and renewable energy. CO 2 emissions and system costs were compared between energy demand and supply scenarios defined with different assumptions on nuclear energy, a CO 2 disposal option, and natural gas imports. Main results were as follows. Without nuclear energy, the CO 2 emissions will hardly be reduced because of the increases of coal utilization. CO 2 disposal will be effective in reducing the emissions, however at much higher costs than the case with nuclear energy. The expansion of natural gas imports alone will not reduce the emissions at enough low levels. (author)

  2. Potential impacts of leakage from deep CO2 geosequestration on overlying freshwater aquifers.

    Science.gov (United States)

    Little, Mark G; Jackson, Robert B

    2010-12-01

    Carbon Capture and Storage may use deep saline aquifers for CO(2) sequestration, but small CO(2) leakage could pose a risk to overlying fresh groundwater. We performed laboratory incubations of CO(2) infiltration under oxidizing conditions for >300 days on samples from four freshwater aquifers to 1) understand how CO(2) leakage affects freshwater quality; 2) develop selection criteria for deep sequestration sites based on inorganic metal contamination caused by CO(2) leaks to shallow aquifers; and 3) identify geochemical signatures for early detection criteria. After exposure to CO(2), water pH declines of 1-2 units were apparent in all aquifer samples. CO(2) caused concentrations of the alkali and alkaline earths and manganese, cobalt, nickel, and iron to increase by more than 2 orders of magnitude. Potentially dangerous uranium and barium increased throughout the entire experiment in some samples. Solid-phase metal mobility, carbonate buffering capacity, and redox state in the shallow overlying aquifers influence the impact of CO(2) leakage and should be considered when selecting deep geosequestration sites. Manganese, iron, calcium, and pH could be used as geochemical markers of a CO(2) leak, as their concentrations increase within 2 weeks of exposure to CO(2).

  3. The pH and pCO2 dependence of sulfate reduction in shallow-sea hydrothermal CO2 – venting sediments (Milos Island, Greece)

    Science.gov (United States)

    Bayraktarov, Elisa; Price, Roy E.; Ferdelman, Timothy G.; Finster, Kai

    2013-01-01

    Microbial sulfate reduction (SR) is a dominant process of organic matter mineralization in sulfate-rich anoxic environments at neutral pH. Recent studies have demonstrated SR in low pH environments, but investigations on the microbial activity at variable pH and CO2 partial pressure are still lacking. In this study, the effect of pH and pCO2 on microbial activity was investigated by incubation experiments with radioactive 35S targeting SR in sediments from the shallow-sea hydrothermal vent system of Milos, Greece, where pH is naturally decreased by CO2 release. Sediments differed in their physicochemical characteristics with distance from the main site of fluid discharge. Adjacent to the vent site (T ~40–75°C, pH ~5), maximal sulfate reduction rates (SRR) were observed between pH 5 and 6. SR in hydrothermally influenced sediments decreased at neutral pH. Sediments unaffected by hydrothermal venting (T ~26°C, pH ~8) expressed the highest SRR between pH 6 and 7. Further experiments investigating the effect of pCO2 on SR revealed a steep decrease in activity when the partial pressure increased from 2 to 3 bar. Findings suggest that sulfate reducing microbial communities associated with hydrothermal vent system are adapted to low pH and high CO2, while communities at control sites required a higher pH for optimal activity. PMID:23658555

  4. The pH and pCO2 dependence of sulfate reduction in shallow-sea hydrothermal CO2 - venting sediments (Milos Island, Greece).

    Science.gov (United States)

    Bayraktarov, Elisa; Price, Roy E; Ferdelman, Timothy G; Finster, Kai

    2013-01-01

    Microbial sulfate reduction (SR) is a dominant process of organic matter mineralization in sulfate-rich anoxic environments at neutral pH. Recent studies have demonstrated SR in low pH environments, but investigations on the microbial activity at variable pH and CO2 partial pressure are still lacking. In this study, the effect of pH and pCO2 on microbial activity was investigated by incubation experiments with radioactive (35)S targeting SR in sediments from the shallow-sea hydrothermal vent system of Milos, Greece, where pH is naturally decreased by CO2 release. Sediments differed in their physicochemical characteristics with distance from the main site of fluid discharge. Adjacent to the vent site (T ~40-75°C, pH ~5), maximal sulfate reduction rates (SRR) were observed between pH 5 and 6. SR in hydrothermally influenced sediments decreased at neutral pH. Sediments unaffected by hydrothermal venting (T ~26°C, pH ~8) expressed the highest SRR between pH 6 and 7. Further experiments investigating the effect of pCO2 on SR revealed a steep decrease in activity when the partial pressure increased from 2 to 3 bar. Findings suggest that sulfate reducing microbial communities associated with hydrothermal vent system are adapted to low pH and high CO2, while communities at control sites required a higher pH for optimal activity.

  5. Storage of Renewable Energy by Reduction of CO2 with Hydrogen.

    Science.gov (United States)

    Züttel, Andreas; Mauron, Philippe; Kato, Shunsuke; Callini, Elsa; Holzer, Marco; Huang, Jianmei

    2015-01-01

    The main difference between the past energy economy during the industrialization period which was mainly based on mining of fossil fuels, e.g. coal, oil and methane and the future energy economy based on renewable energy is the requirement for storage of the energy fluxes. Renewable energy, except biomass, appears in time- and location-dependent energy fluxes as heat or electricity upon conversion. Storage and transport of energy requires a high energy density and has to be realized in a closed materials cycle. The hydrogen cycle, i.e. production of hydrogen from water by renewable energy, storage and use of hydrogen in fuel cells, combustion engines or turbines, is a closed cycle. However, the hydrogen density in a storage system is limited to 20 mass% and 150 kg/m(3) which limits the energy density to about half of the energy density in fossil fuels. Introducing CO(2) into the cycle and storing hydrogen by the reduction of CO(2) to hydrocarbons allows renewable energy to be converted into synthetic fuels with the same energy density as fossil fuels. The resulting cycle is a closed cycle (CO(2) neutral) if CO(2) is extracted from the atmosphere. Today's technology allows CO(2) to be reduced either by the Sabatier reaction to methane, by the reversed water gas shift reaction to CO and further reduction of CO by the Fischer-Tropsch synthesis (FTS) to hydrocarbons or over methanol to gasoline. The overall process can only be realized on a very large scale, because the large number of by-products of FTS requires the use of a refinery. Therefore, a well-controlled reaction to a specific product is required for the efficient conversion of renewable energy (electricity) into an easy to store liquid hydrocarbon (fuel). In order to realize a closed hydrocarbon cycle the two major challenges are to extract CO(2) from the atmosphere close to the thermodynamic limit and to reduce CO(2) with hydrogen in a controlled reaction to a specific hydrocarbon. Nanomaterials with

  6. Energy efficiency improvement and CO2 emission reduction opportunities in the cement industry in China

    International Nuclear Information System (INIS)

    Hasanbeigi, Ali; Morrow, William; Masanet, Eric; Sathaye, Jayant; Xu, Tengfang

    2013-01-01

    China's annual cement production (i.e., 1868 Mt) in 2010 accounted for nearly half of the world's annual cement production in the same year. We identified and analyzed 23 energy efficiency technologies and measures applicable to the processes in China's cement industry. The Conservation Supply Curve (CSC) used in this study is an analytical tool that captures both the engineering and the economic perspectives of energy conservation. Using bottom–up CSC models, the cumulative cost-effective and technical electricity and fuel savings, as well as the CO 2 emission reduction potentials for the Chinese cement industry for 2010–2030 are estimated. By comparison, the total final energy saving achieved by the implementation of these 23 efficiency measures in the Chinese cement industry over 20 years (2010–2030) is equal to 30% of the total primary energy supply of Latin America or Middle East or around 71% of primary energy supply of Brazil in 2007. In addition, a sensitivity analysis with respect to the discount rate is conducted to assess its effect on the results. The result of this study gives a comprehensive and easy to understand perspective to the Chinese cement industry and policy makers about the energy efficiency potential and its associated cost. - Highlights: ► Estimation of energy saving potential in the entire Chinese cement industry. ► Development of the bottom–up technology-rich Conservation Supply Curve models. ► Discussion of different approaches for developing conservation supply curves. ► Primary energy saving over 20 years equal to 33% of primary energy of Latin America

  7. Alternative photocatalysts to TiO2 for the photocatalytic reduction of CO2

    Science.gov (United States)

    Nikokavoura, Aspasia; Trapalis, Christos

    2017-01-01

    The increased concentration of CO2 in the atmosphere, originating from the burning of fossil fuels in stationary and mobile sources, is referred as the "Anthropogenic Greenhouse Effect" and constitutes a major environmental concern. The scientific community is highly concerned about the resulting enhancement of the mean atmospheric temperature, so a vast diversity of methods has been applied. Thermochemical, electrochemical, photocatalytic, photoelectrochemical processes, as well as combination of solar electricity generation and water splitting processes have been performed in order to lower the CO2 atmospheric levels. Photocatalytic methods are environmental friendly and succeed in reducing the atmospheric CO2 concentration and producing fuels or/and useful organic compounds at the same time. The most common photocatalysts for the CO2 reduction are the inorganic, the carbon based semiconductors and the hybrids based on semiconductors, which combine stability, low cost and appropriate structure in order to accomplish redox reactions. In this review, inorganic semiconductors such as single-metal oxide, mixed-metal oxides, metal oxide composites, layered double hydroxides (LDHs), salt composites, carbon based semiconductors such as graphene based composites, CNT composites, g-C3N4 composites and hybrid organic-inorganic materials (ZIFs) were studied. TiO2 and Ti based photocatalysts are extensively studied and therefore in this review they are not mentioned.

  8. A Polarizable and Transferable PHAST CO 2 Potential for Materials Simulation

    KAUST Repository

    Mullen, Ashley L.; Pham, Tony; Forrest, Katherine A.; Cioce, Christian R.; McLaughlin, Keith; Space, Brian

    2013-01-01

    Reliable PHAST (Potentials with High Accuracy Speed and Transferability) intermolecular potential energy functions for CO2 have been developed from first principles for use in heterogeneous systems, including one with explicit polarization

  9. Environmental potential of the use of CO_2 from alcoholic fermentation processes. The CO_2-AFP strategy

    International Nuclear Information System (INIS)

    Alonso-Moreno, Carlos; García-Yuste, Santiago

    2016-01-01

    A novel Carbon Dioxide Utilization (CDU) approach from a relatively minor CO_2 emission source, i.e., alcoholic fermentation processes (AFP), is presented. The CO_2 produced as a by-product from the AFP is estimated by examining the EtOH consumed per year reported by the World Health Organization in 2014. It is proposed that the extremely pure CO_2 from the AFP is captured in NaOH solutions to produce one of the Top 10 commodities in the chemical industry, Na_2CO_3, as a good example of an atomic economy process. The novel CDU strategy could yield over 30.6 Mt of Na_2CO_3 in oversaturated aqueous solution on using ca. 12.7 Mt of captured CO_2 and this process would consume less energy than the synthetic methodology (Solvay ammonia soda process) and would not produce low-value by-products. The quantity of Na_2CO_3 obtained by this strategy could represent ca. 50% of the world Na_2CO_3 production in one year. In terms of the green economy, the viability of the strategy is discussed according to the recommendations of the CO_2Chem network, and an estimation of the CO_2negative emission achieved suggests a capture of around 280.0 Mt of CO_2 from now to 2020 or ca. 1.9 Gt from now to 2050. Finally, the results obtained for this new CDU proposal are discussed by considering different scenarios; the CO_2 production in a typical winemaking corporation, the CO_2 released in the most relevant wine-producing countries, and the use of CO_2 from AFP as an alternative for the top Na_2CO_3-producing countries. - Highlights: • A new CDU strategy to mitigate the CO_2 in the atmosphere is assessed. • An environmental action towards negligible emission sources such as AFP. • The waste CO_2 from AFP could be converted into Na_2CO_3. • Capture 12.7 Mt yr"–"1 of CO_2 to generate ca. 1.9 Gt of CO_2negative emissions by 2050.

  10. Analytical model for screening potential CO2 repositories

    Science.gov (United States)

    Okwen, R.T.; Stewart, M.T.; Cunningham, J.A.

    2011-01-01

    Assessing potential repositories for geologic sequestration of carbon dioxide using numerical models can be complicated, costly, and time-consuming, especially when faced with the challenge of selecting a repository from a multitude of potential repositories. This paper presents a set of simple analytical equations (model), based on the work of previous researchers, that could be used to evaluate the suitability of candidate repositories for subsurface sequestration of carbon dioxide. We considered the injection of carbon dioxide at a constant rate into a confined saline aquifer via a fully perforated vertical injection well. The validity of the analytical model was assessed via comparison with the TOUGH2 numerical model. The metrics used in comparing the two models include (1) spatial variations in formation pressure and (2) vertically integrated brine saturation profile. The analytical model and TOUGH2 show excellent agreement in their results when similar input conditions and assumptions are applied in both. The analytical model neglects capillary pressure and the pressure dependence of fluid properties. However, simulations in TOUGH2 indicate that little error is introduced by these simplifications. Sensitivity studies indicate that the agreement between the analytical model and TOUGH2 depends strongly on (1) the residual brine saturation, (2) the difference in density between carbon dioxide and resident brine (buoyancy), and (3) the relationship between relative permeability and brine saturation. The results achieved suggest that the analytical model is valid when the relationship between relative permeability and brine saturation is linear or quasi-linear and when the irreducible saturation of brine is zero or very small. ?? 2011 Springer Science+Business Media B.V.

  11. Electrochemical CO2 and CO reduction on metal-functionalized porphyrin-like graphene

    DEFF Research Database (Denmark)

    Tripkovic, Vladimir; Vanin, Marco; Karamad, Mohammedreza

    2013-01-01

    Porphyrin-like metal-functionalized graphene structures have been investigated as possible catalysts for CO2 and CO reduction to methane or methanol. The late transition metals (Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Ru, Os) and some p (B, Al, Ga) and s (Mg) metals comprised the center of the po......Porphyrin-like metal-functionalized graphene structures have been investigated as possible catalysts for CO2 and CO reduction to methane or methanol. The late transition metals (Cu, Ag, Au, Ni, Pd, Pt, Co, Rh, Ir, Fe, Ru, Os) and some p (B, Al, Ga) and s (Mg) metals comprised the center...... instead of CO2. Volcano plots were constructed on the basis of scaling relations of reaction intermediates, and from these plots the reaction steps with the highest overpotentials were deduced. The Rh-porphyrin-like functionalized graphene was identified as the most active catalyst for producing methanol...... from CO, featuring an overpotential of 0.22 V. Additionally, we have also examined the hydrogen evolution and oxidation reaction, and in their case, too, Rh-porphyrin turned out to be the best catalyst with an overpotential of 0.15 V. © 2013 American Chemical Society....

  12. How to Achieve CO2 Emission Reduction Goals: What 'Jazz' and 'Symphony' Can Offer

    International Nuclear Information System (INIS)

    Rose, K.

    2013-01-01

    Achieving CO 2 emission reduction goals remains one of today's most challenging tasks. Global energy demand will grow for many decades to come. In many regions of the world cheap fossil fuels seem to be the way forward to meet ever growing energy demand. However, there are negative consequences to this, most notably increasing emission levels. Politicians and industry therefore must accept that make hard choices in this generation need to be made to bring about real changes for future generations and the planet to limit CO 2 emissions and climate change. In his presentation, prof. Rose will provide an insight into how CO 2 emission reduction goals can be set and achieved and how a balance between future energy needs and supply can be realised in the long run up to 2050 both globally and regionally. This will be done based on WEC's own leading analysis in this area, namely it recently launched World Energy Scenarios: composing energy futures to 2050 report and WEC's scenarios, Jazz and Symphony. WEC's full analysis, the complete report and supporting material is available online at: http://www.worldenergy.org/publications/2013/world-energy-scenarios-composing-energy-futures-to-2050.(author)

  13. Electrochemical Reduction of CO2 on IrxRu(1–x)O2(110) Surfaces 

    DEFF Research Database (Denmark)

    Bhowmik, Arghya; Hansen, Heine Anton; Vegge, Tejs

    2017-01-01

    with oxygen-coordinated intermediates that can circumvent the limitations imposed by the scaling relations on metal catalysts. Here, we introduce an innovative concept of ligand effects in oxide catalysts. Both IrO2 and RuO2 binds OH* and other intermediates from the electrochemical reduction of CO2 (CO2RR......High overpotentials and low faradic efficiencies plague metal catalysts for direct conversion of CO2 to methanol and other liquid fuels. RuO2-based electrocatalysts have been observed to evolve methanol at low overpotentials, which has been attributed to an alternative reaction mechanism......) strongly, but the stable and miscible system IrxRu(1-x)O2 exhibits anomalous weaker binding energy in the presence of CO* spectators, because of Ru–Ir ligand effects. The weakened adsorbate binding leads to a very low CO2RR onset potential (methanol evolution at −0.2 V RHE). An Ir atom at the bridge site...

  14. Cofactor and CO2 donor regulation involved in reductive routes for polymalic acid production by Aureobasidium pullulans CCTCC M2012223.

    Science.gov (United States)

    Zou, Xiang; Tu, Guangwei; Zan, Zhanquan

    2014-10-01

    Polymalic acid (PMA) is a water-soluble polyester with many attractive properties for biomedical application. Its monomer L-malic acid is widely used in the food industry and also a potential C4 platform chemical. Cofactor and CO2 donor involved in the reductive routes were investigated for PMA production by Aureobasidium pullulans. Biotin as the key cofactor of pyruvate carboxylase was favor for the PMA biosynthesis. Na2CO3 as CO2 donor can obviously improved PMA titer when compared with no CO2 supplier NaOH, and also exhibit more advantages than the other donor CaCO3 because of its water-soluble characteristic. A combinational process with addition of biotin 70 mg/L and Na2CO3 as the CO2 donor was scaled-up in 50 L fermentor, achieving the high product 34.3 g/L of PMA and productivity of 0.41 g/L h. This process provides an efficient and economical way for PMA and malic acid production, and is promising for industrial application.

  15. Possibilities for the reduction of CO2- and CH4-emissions of natural gas

    International Nuclear Information System (INIS)

    Muessig, S.

    1994-01-01

    The use of fossil fuels increases the portion of greenhouse gases, especially CO 2 and CH 4 . In this paper firstly the specific emission rates of these greenhouse gases for the various fuels are compared. Secondly possibilities for the reduction of CO 2 and CH 4 for natural gas which are relatively small anyhow are discussed. Thirdly the use of renewable energy within the gas industry and the ocean and into depleted reservoirs are discussed. It is shown that the efficient use of energy of the fossil fuel natural gas is most successful in all branches of gas consumption to decrease emission. Combined-cycle processes, cogeneration as well as modern domestic heating systems are described. Fuel cells and the application of hydrogen is shortly discussed. (orig.)

  16. Heterogeneous electrochemical CO2 reduction using nonmetallic carbon-based catalysts: current status and future challenges

    Science.gov (United States)

    Ma, Tao; Fan, Qun; Tao, Hengcong; Han, Zishan; Jia, Mingwen; Gao, Yunnan; Ma, Wangjing; Sun, Zhenyu

    2017-11-01

    Electrochemical CO2 reduction (ECR) offers an important pathway for renewable energy storage and fuels production. It still remains a challenge in designing highly selective, energy-efficient, robust, and cost-effective electrocatalysts to facilitate this kinetically slow process. Metal-free carbon-based materials have features of low cost, good electrical conductivity, renewability, diverse structure, and tunability in surface chemistry. In particular, surface functionalization of carbon materials, for example by doping with heteroatoms, enables access to unique active site architectures for CO2 adsorption and activation, leading to interesting catalytic performances in ECR. We aim to provide a comprehensive review of this category of metal-free catalysts for ECR, providing discussions and/or comparisons among different nonmetallic catalysts, and also possible origin of catalytic activity. Fundamentals and some future challenges are also described.

  17. The role of reticular chemistry in the design of CO2 reduction catalysts

    Science.gov (United States)

    Diercks, Christian S.; Liu, Yuzhong; Cordova, Kyle E.; Yaghi, Omar M.

    2018-02-01

    The problem with current state-of-the-art catalysts for CO2 photo- or electroreduction is rooted in the notion that no single system can independently control, and thus optimize, the interplay between activity, selectivity and efficiency. At its core, reticular chemistry is recognized for its ability to control, with atomic precision, the chemical and structural features (activity and selectivity) as well as the output optoelectronic properties (efficiency) of porous, crystalline materials. The molecular building blocks that are in a reticular chemist's toolbox are chosen in such a way that the structures are rationally designed, framework chemistry is performed to integrate catalytically active components, and the manner in which these building blocks are connected endows the material with the desired optoelectronic properties. The fact that these aspects can be fine-tuned independently lends credence to the prospect of reticular chemistry contributing to the design of next-generation CO2 reduction catalysts.

  18. CO2 uptake potential due to concrete carbonation: A case study

    Directory of Open Access Journals (Sweden)

    Edna Possan

    2017-06-01

    Full Text Available The cement manufacturing process accounts for about 5% CO2 (carbon dioxide released into the atmosphere. However, during its life cycle, concrete may capture CO2 through carbonation, in order to, partially, offset the impact of its production. Thus, this paper aims at studying the CO2 uptake potential of the Itaipu Dam due to concrete carbonation of such material. So, 155 cores were extracted from the concrete dam in different points to measure carbonation depth. In order to evaluate its influence on carbonation, the measurement of internal moisture distribution in concrete was also carried out. The results have shown that carbonation takes part of the whole dam area, indicating CO2 uptake potential. Up to the present moment, 13,384 tons of CO2 have been absorbed by concrete carbonation of the Itaipu Dam.

  19. Assessment of CO2 Storage Potential in Naturally Fractured Reservoirs With Dual-Porosity Models

    Science.gov (United States)

    March, Rafael; Doster, Florian; Geiger, Sebastian

    2018-03-01

    Naturally Fractured Reservoirs (NFR's) have received little attention as potential CO2 storage sites. Two main facts deter from storage projects in fractured reservoirs: (1) CO2 tends to be nonwetting in target formations and capillary forces will keep CO2 in the fractures, which typically have low pore volume; and (2) the high conductivity of the fractures may lead to increased spatial spreading of the CO2 plume. Numerical simulations are a powerful tool to understand the physics behind brine-CO2 flow in NFR's. Dual-porosity models are typically used to simulate multiphase flow in fractured formations. However, existing dual-porosity models are based on crude approximations of the matrix-fracture fluid transfer processes and often fail to capture the dynamics of fluid exchange accurately. Therefore, more accurate transfer functions are needed in order to evaluate the CO2 transfer to the matrix. This work presents an assessment of CO2 storage potential in NFR's using dual-porosity models. We investigate the impact of a system of fractures on storage in a saline aquifer, by analyzing the time scales of brine drainage by CO2 in the matrix blocks and the maximum CO2 that can be stored in the rock matrix. A new model to estimate drainage time scales is developed and used in a transfer function for dual-porosity simulations. We then analyze how injection rates should be limited in order to avoid early spill of CO2 (lost control of the plume) on a conceptual anticline model. Numerical simulations on the anticline show that naturally fractured reservoirs may be used to store CO2.

  20. Atmospheric stabilization of CO2 emissions: Near-term reductions and absolute versus intensity-based targets

    International Nuclear Information System (INIS)

    Timilsina, Govinda R.

    2008-01-01

    This study analyzes CO 2 emissions reduction targets for various countries and geopolitical regions by the year 2030 to stabilize atmospheric concentrations of CO 2 at 450 ppm (550 ppm including non-CO 2 greenhouse gases) level. It also determines CO 2 intensity cuts that would be required in those countries and regions if the emission reductions were to be achieved through intensity-based targets without curtailing their expected economic growth. Considering that the stabilization of CO 2 concentrations at 450 ppm requires the global trend of CO 2 emissions to be reversed before 2030, this study develops two scenarios: reversing the global CO 2 trend in (i) 2020 and (ii) 2025. The study shows that global CO 2 emissions would be limited at 42 percent above 1990 level in 2030 if the increasing trend of global CO 2 emissions were to be reversed by 2020. If reversing the trend is delayed by 5 years, global CO 2 emissions in 2030 would be 52 percent higher than the 1990 level. The study also finds that to achieve these targets while maintaining expected economic growth, the global average CO 2 intensity would require a 68 percent drop from the 1990 level or a 60 percent drop from the 2004 level by 2030

  1. Improving yield potential in crops under elevated CO(2): Integrating the photosynthetic and nitrogen utilization efficiencies.

    Science.gov (United States)

    Kant, Surya; Seneweera, Saman; Rodin, Joakim; Materne, Michael; Burch, David; Rothstein, Steven J; Spangenberg, German

    2012-01-01

    Increasing crop productivity to meet burgeoning human food demand is challenging under changing environmental conditions. Since industrial revolution atmospheric CO(2) levels have linearly increased. Developing crop varieties with increased utilization of CO(2) for photosynthesis is an urgent requirement to cope with the irreversible rise of atmospheric CO(2) and achieve higher food production. The primary effects of elevated CO(2) levels in most crop plants, particularly C(3) plants, include increased biomass accumulation, although initial stimulation of net photosynthesis rate is only temporal and plants fail to sustain the maximal stimulation, a phenomenon known as photosynthesis acclimation. Despite this acclimation, grain yield is known to marginally increase under elevated CO(2). The yield potential of C(3) crops is limited by their capacity to exploit sufficient carbon. The "C fertilization" through elevated CO(2) levels could potentially be used for substantial yield increase. Rubisco is the rate-limiting enzyme in photosynthesis and its activity is largely affected by atmospheric CO(2) and nitrogen availability. In addition, maintenance of the C/N ratio is pivotal for various growth and development processes in plants governing yield and seed quality. For maximizing the benefits of elevated CO(2), raising plant nitrogen pools will be necessary as part of maintaining an optimal C/N balance. In this review, we discuss potential causes for the stagnation in yield increases under elevated CO(2) levels and explore possibilities to overcome this limitation by improved photosynthetic capacity and enhanced nitrogen use efficiency. Opportunities of engineering nitrogen uptake, assimilatory, and responsive genes are also discussed that could ensure optimal nitrogen allocation toward expanding source and sink tissues. This might avert photosynthetic acclimation partially or completely and drive for improved crop production under elevated CO(2) levels.

  2. Improving yield potential in crops under elevated CO2: Integrating the photosynthetic and nitrogen utilization efficiencies

    Science.gov (United States)

    Kant, Surya; Seneweera, Saman; Rodin, Joakim; Materne, Michael; Burch, David; Rothstein, Steven J.; Spangenberg, German

    2012-01-01

    Increasing crop productivity to meet burgeoning human food demand is challenging under changing environmental conditions. Since industrial revolution atmospheric CO2 levels have linearly increased. Developing crop varieties with increased utilization of CO2 for photosynthesis is an urgent requirement to cope with the irreversible rise of atmospheric CO2 and achieve higher food production. The primary effects of elevated CO2 levels in most crop plants, particularly C3 plants, include increased biomass accumulation, although initial stimulation of net photosynthesis rate is only temporal and plants fail to sustain the maximal stimulation, a phenomenon known as photosynthesis acclimation. Despite this acclimation, grain yield is known to marginally increase under elevated CO2. The yield potential of C3 crops is limited by their capacity to exploit sufficient carbon. The “C fertilization” through elevated CO2 levels could potentially be used for substantial yield increase. Rubisco is the rate-limiting enzyme in photosynthesis and its activity is largely affected by atmospheric CO2 and nitrogen availability. In addition, maintenance of the C/N ratio is pivotal for various growth and development processes in plants governing yield and seed quality. For maximizing the benefits of elevated CO2, raising plant nitrogen pools will be necessary as part of maintaining an optimal C/N balance. In this review, we discuss potential causes for the stagnation in yield increases under elevated CO2 levels and explore possibilities to overcome this limitation by improved photosynthetic capacity and enhanced nitrogen use efficiency. Opportunities of engineering nitrogen uptake, assimilatory, and responsive genes are also discussed that could ensure optimal nitrogen allocation toward expanding source and sink tissues. This might avert photosynthetic acclimation partially or completely and drive for improved crop production under elevated CO2 levels. PMID:22833749

  3. More gas, less coal, and less CO2? Unilateral CO2 reduction policy with more than one carbon energy source

    DEFF Research Database (Denmark)

    Daubanes, Julien Xavier; Henriet, Fanny; Schubert, Katheline

    -productive, ultimately increasing world emissions. Thus, we establish testable conditions as to whether a governmental emission-reduction commitment warrants the exploitation of gas, and whether such a strategy increases global emissions. We also characterize the extent to which this unilateral policy makes the rest...... of the world’s emission commitments more difficult to meet. Finally, we apply our results to the case of the US....

  4. Reduction of CO2 Emissions in Houses of Historic and Visual Importance

    Directory of Open Access Journals (Sweden)

    Birgit Dulski

    2010-01-01

    Full Text Available According to the ‘Climate Programme’ the municipality of Amsterdam has the ambition to reduce the CO2 emissions within the city limits by 40% in the year 2025 compared to the year 1990. To realize this ambition substantial CO2 savings have to be realized at the 375,000 current houses in the city. A special challenge is formed by the houses of historic and visual importance, as the implementation of standard energy saving measures may conflict with the ambition to protect their cultural and historic values. Nyenrode Business University was asked to study the possibilities for a successful combination of ambitions in both fields. This article shows an overview of suggestions that focus on the combination of technical and process orientated innovations which can contribute to the acceleration of the reduction of CO2 emissions in houses of historic and visual importance. The article therefore addresses political and technical as well as financial and process related aspects in implementing energy saving measures in this category of buildings.

  5. Effects of Eco-Drive Education on the Reduction of Fuel Consumption and CO2 Emissions

    OpenAIRE

    Barić, Danijela; Zovak, Goran; Periša, Marko

    2013-01-01

    Sustainable mobility is the basic and long-term goal of the traffic policy. Eco-driving represents one of 40 measures that should by 2050 contribute to 60% of traffic-generated emission reduction. The paper presents the significance of educating the drivers about eco-driving as well as eco-drive training with the aim of reducing fuel consumption and CO2 emission. During research the drivers were tested in three cycles, prior to education, immediately following the education and eco-training a...

  6. CO2 reduction in the Danish transportation sector. Working paper 3: Tax differentiation and environmental tagging

    International Nuclear Information System (INIS)

    1997-03-01

    Tax differentiation for cars would mean a new structure of the buyer market as the decisive factor in new car price is its fuel efficiency and environmentally friendly low CO 2 emission. Reduction of fuel cost per kilometer can result in increased annual car use. On the other hand growing sales of cars in Denmark would give extra profit to the state as purchase taxation and weight-dependent tax are both extremely high. Environmental tagging can increase consumer awareness of fuel efficiency and emission control. (EG) Prepared for Trafikministeriet. 13 refs

  7. Efficient Electrocatalytic Reduction of CO2 by Nitrogen-Doped Nanoporous Carbon/Carbon Nanotube Membranes - A Step Towards the Electrochemical CO2 Refinery

    KAUST Repository

    Wang, Hong; Jia, Jia; Song, Pengfei; Wang, Qiang; Li, Debao; Min, Shixiong; Qian, Chenxi; Wang, Lu; Li, Young Feng; Ma, Chun; Wu, Tao; Yuan, Jiayin; Antonietti, Markus; Ozin, Geoffrey A.

    2017-01-01

    The search for earth abundant, efficient and stable electrocatalysts that can enable the chemical reduction of CO2 to value-added chemicals and fuels at an industrially relevant scale, is a high priority for the development of a global network of renewable energy conversion and storage systems that can meaningfully impact greenhouse gas induced climate change. Here we introduce a straightforward, low cost, scalable and technologically relevant method to manufacture an all-carbon, electroactive, nitrogen-doped nanoporous carbon-carbon nanotube composite membrane. The membrane is demonstrated to function as a binder-free, high-performance electrode for the electrocatalytic reduction of CO2 to formate. The Faradaic efficiency for the production of formate is 81%. Furthermore, the robust structural and electrochemical properties of the membrane endow it with excellent long-term stability.

  8. Efficient Electrocatalytic Reduction of CO2 by Nitrogen-Doped Nanoporous Carbon/Carbon Nanotube Membranes - A Step Towards the Electrochemical CO2 Refinery

    KAUST Repository

    Wang, Hong

    2017-05-12

    The search for earth abundant, efficient and stable electrocatalysts that can enable the chemical reduction of CO2 to value-added chemicals and fuels at an industrially relevant scale, is a high priority for the development of a global network of renewable energy conversion and storage systems that can meaningfully impact greenhouse gas induced climate change. Here we introduce a straightforward, low cost, scalable and technologically relevant method to manufacture an all-carbon, electroactive, nitrogen-doped nanoporous carbon-carbon nanotube composite membrane. The membrane is demonstrated to function as a binder-free, high-performance electrode for the electrocatalytic reduction of CO2 to formate. The Faradaic efficiency for the production of formate is 81%. Furthermore, the robust structural and electrochemical properties of the membrane endow it with excellent long-term stability.

  9. Surface-reconstructed Cu Electrode via a Facile Electrochemical Anodization-Reduction Process for Low Overpotential CO 2 reduction

    KAUST Repository

    Min, Shixiong

    2017-03-21

    A high-surface-area Cu electrode, fabricated by a simple electrochemical anodization-reduction method, exhibits high activity and selectivity for CO2 reduction at low overpotential in 0.1 M KHCO3 solution. A faradaic efficiency of 37% for HCOOH and 27% for CO production was achieved with the current density of 1.5 mA cm-2 at −0.64 V vs. RHE, much higher than that of polycrystalline Cu. The enhanced catalytic performance is a result of the formation of the high electrochemical active surface area and high density of preferred low-index facets.

  10. Potential impact of rising atmospheric CO2 on quality of grains in chickpea (Cicer arietinum L.).

    Science.gov (United States)

    Saha, Saurav; Chakraborty, Debashis; Sehgal, Vinay K; Pal, Madan

    2015-11-15

    Experiments were conducted in open-top chambers to assess the effect of atmospheric CO2 enrichment (E-CO2) on the quality of grains in chickpea (Cicer arietinum L.) crop. Physical attributes of the grains was not affected, but the hydration and swelling capacities of the flour increased. Increase in carbohydrates and reduction in protein made the grains more carbonaceous (higher C:N) under E-CO2. Among other mineral nutrients, K, Ca and Zn concentrations decreased, while P, Mg, Cu, Fe, Mn and B concentrations did not change. The pH, bulk density and cooking time of chickpea flour remained unaffected, although the water absorption capacity of flour increased and oil absorption reduced. Results suggest that E-CO2 could affect the grain quality adversely and nutritional imbalance in grains of chickpea might occur. Copyright © 2015. Published by Elsevier Ltd.

  11. Plasma for electrification of chemical industry: a case study on CO2 reduction

    Science.gov (United States)

    van Rooij, G. J.; Akse, H. N.; Bongers, W. A.; van de Sanden, M. C. M.

    2018-01-01

    Significant growth of the share of (intermittent) renewable power in the chemical industry is imperative to meet increasingly stricter limits on CO2 exhaust that are being implemented within Europe. This paper aims to evaluate the potential of a plasma process that converts input CO2 into a pure stream of CO to aid in renewable energy penetration in this sector. A realistic process design is constructed to serve as a basis for an economical analysis. The manufacturing cost price of CO is estimated at 1.2 kUS ton-1 CO. A sensitivity analysis shows that separation is the dominant cost factor, so that improving conversion is currently more effective to lower the price than e.g. energy efficiency.

  12. Element mobilization and immobilization from carbonate rocks between CO 2 storage reservoirs and the overlying aquifers during a potential CO 2 leakage

    Energy Technology Data Exchange (ETDEWEB)

    Lawter, Amanda R.; Qafoku, Nikolla P.; Asmussen, R. Matthew; Kukkadapu, Ravi K.; Qafoku, Odeta; Bacon, Diana H.; Brown, Christopher F.

    2018-04-01

    Despite the numerous studies on changes within the reservoir following CO2 injection and the effects of CO2 release into overlying aquifers, little or no literature is available on the effect of CO2 release on rock between the storage reservoirs and subsurface. To address this knowledge gap, relevant rock materials, temperatures and pressures were used to study mineralogical and elemental changes in this intermediate zone. After rocks reacted with CO2, liquid analysis showed an increase of major elements (e.g., Ca, and Mg) and variable concentrations of potential contaminants (e.g., Sr and Ba); lower concentrations were observed in N2 controls. In experiments with As/Cd and/or organic spikes, representing potential contaminants in the CO2 plume originating in the storage reservoir, most or all of these contaminants were removed from the aqueous phase. SEM and Mössbauer spectroscopy results showed the formation of new minerals and Fe oxides in some CO2-reacted samples, indicating potential for contaminant removal through mineral incorporation or adsorption onto Fe oxides. These experiments show the interactions between the CO2-laden plume and the rock between storage reservoirs and overlying aquifers have the potential to affect the level of risk to overlying groundwater, and should be considered during site selection and risk evaluation.

  13. Copper-Based Metal-Organic Porous Materials for CO2 Electrocatalytic Reduction to Alcohols.

    Science.gov (United States)

    Albo, Jonathan; Vallejo, Daniel; Beobide, Garikoitz; Castillo, Oscar; Castaño, Pedro; Irabien, Angel

    2017-03-22

    The electrocatalytic reduction of CO 2 has been investigated using four Cu-based metal-organic porous materials supported on gas diffusion electrodes, namely, (1) HKUST-1 metal-organic framework (MOF), [Cu 3 (μ 6 -C 9 H 3 O 6 ) 2 ] n ; (2) CuAdeAce MOF, [Cu 3 (μ 3 -C 5 H 4 N 5 ) 2 ] n ; (3) CuDTA mesoporous metal-organic aerogel (MOA), [Cu(μ-C 2 H 2 N 2 S 2 )] n ; and (4) CuZnDTA MOA, [Cu 0.6 Zn 0.4 (μ-C 2 H 2 N 2 S 2 )] n . The electrodes show relatively high surface areas, accessibilities, and exposure of the Cu catalytic centers as well as favorable electrocatalytic CO 2 reduction performance, that is, they have a high efficiency for the production of methanol and ethanol in the liquid phase. The maximum cumulative Faradaic efficiencies for CO 2 conversion at HKUST-1-, CuAdeAce-, CuDTA-, and CuZnDTA-based electrodes are 15.9, 1.2, 6, and 9.9 %, respectively, at a current density of 10 mA cm -2 , an electrolyte-flow/area ratio of 3 mL min cm -2 , and a gas-flow/area ratio of 20 mL min cm -2 . We can correlate these observations with the structural features of the electrodes. Furthermore, HKUST-1- and CuZnDTA-based electrodes show stable electrocatalytic performance for 17 and 12 h, respectively. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Evaluating Potential for Large Releases from CO2 Storage Reservoirs: Analogs, Scenarios, and Modeling Needs

    International Nuclear Information System (INIS)

    Birkholzer, Jens; Pruess, Karsten; Lewicki, Jennifer; Tsang, Chin-Fu; Karimjee, Anhar

    2005-01-01

    While the purpose of geologic storage of CO 2 in deep saline formations is to trap greenhouse gases underground, the potential exists for CO 2 to escape from the target reservoir, migrate upward along permeable pathways, and discharge at the land surface. Such discharge is not necessarily a serious concern, as CO 2 is a naturally abundant and relatively benign gas in low concentrations. However, there is a potential risk to health, safety and environment (HSE) in the event that large localized fluxes of CO 2 were to occur at the land surface, especially where CO 2 could accumulate. In this paper, we develop possible scenarios for large CO 2 fluxes based on the analysis of natural analogues, where large releases of gas have been observed. We are particularly interested in scenarios which could generate sudden, possibly self-enhancing, or even eruptive release events. The probability for such events may be low, but the circumstances under which they might occur and potential consequences need to be evaluated in order to design appropriate site selection and risk management strategies. Numerical modeling of hypothetical test cases is needed to determine critical conditions for such events, to evaluate whether such conditions may be possible at designated storage sites, and, if applicable, to evaluate the potential HSE impacts of such events and design appropriate mitigation strategies

  15. CO2 Reduction Assembly Prototype Using Microlith-Based Sabatier Reactor for Ground Demonstration

    Science.gov (United States)

    Junaedi, Christian; Hawley, Kyle; Walsh, Dennis; Roychoudhury, Subir; Abney, Morgan B.; Perry, Jay L.

    2014-01-01

    The utilization of CO2 to produce life support consumables, such as O2 and H2O, via the Sabatier reaction is an important aspect of NASA's cabin Atmosphere Revitalization System (ARS) and In-Situ Resource Utilization (ISRU) architectures for both low-earth orbit and long-term manned space missions. Carbon dioxide can be reacted with H2, obtained from the electrolysis of water, via Sabatier reaction to produce methane and H2O. Methane can be stored and utilized as propellant while H2O can be either stored or electrolyzed to produce oxygen and regain the hydrogen atoms. Depending on the application, O2 can be used to replenish the atmosphere in human-crewed missions or as an oxidant for robotic and return missions. Precision Combustion, Inc. (PCI), with support from NASA, has previously developed an efficient and compact Sabatier reactor based on its Microlith® catalytic technology and demonstrated the capability to achieve high CO2 conversion and CH4 selectivity (i.e., =90% of the thermodynamic equilibrium values) at high space velocities and low operating temperatures. This was made possible through the use of high-heat-transfer and high-surface-area Microlith catalytic substrates. Using this Sabatier reactor, PCI designed, developed, and demonstrated a stand-alone CO2 Reduction Assembly (CRA) test system for ground demonstration and performance validation. The Sabatier reactor was integrated with the necessary balance-of-plant components and controls system, allowing an automated, single "push-button" start-up and shutdown. Additionally, the versatility of the test system prototype was demonstrated by operating it under H2-rich (H2/CO2 of >4), stoichiometric (ratio of 4), and CO2-rich conditions (ratio of <4) without affecting its performance and meeting the equilibrium-predicted water recovery rates. In this paper, the development of the CRA test system for ground demonstration will be discussed. Additionally, the performance results from testing the system at

  16. The Catalytic Bias of 2-Oxoacid:ferredoxin Oxidoreductase in CO_2: evolution and reduction through a ferredoxin-mediated electrocatalytic assay

    International Nuclear Information System (INIS)

    Li, Bin; Elliott, Sean J.

    2016-01-01

    Enzymes from the 2-oxoacid: ferredoxin oxidoreductase (OFOR) family engage in both CO_2 evolution and reduction in nature, depending on their physiological roles. Two enzymes and their redox partner ferredoxins (Fds) from Hydrogenobacter thermophilus and Desulfovibrio africanus were examined to investigate the basis of the catalytic bias. The Fd1 from H. thermophilus demonstrated a potential of ∼ −485 mV at room temperature, the lowest for known single [4Fe-4S] cluster Fds. It suggests a low potential electron donor may be the key factor in overcoming the large thermodynamic barrier of CO_2 reduction. The Fd-mediated electrocatalytic experiments further demonstrated the impact of Fd’s potential on the direction of the OFOR reaction: as OFOR enzymes could essentially catalyze both CO_2 evolution and reduction in vitro, the difference in their physiological roles is associated with the reduction potential of the redox partner Fd. The electrocatalytic assay could study both CO_2 evolution and reduction in one setup and is a good tool to probe Fds’ reactivity that arise from their reduction potentials.

  17. National energy policies: Obstructing the reduction of global CO2 emissions? An analysis of Swedish energy policies for the district heating sector

    International Nuclear Information System (INIS)

    Difs, Kristina

    2010-01-01

    The effect of national energy policies on a local Swedish district heating (DH) system has been studied, regarding the profitability of new investments and the potential for climate change mitigation. The DH system has been optimised regarding three investments: biomass-fuelled CHP (bio CHP), natural gas-fuelled combined cycle CHP (NGCC CHP) and biomass-fuelled heat-only boiler (bio HOB) in two scenarios (with or without national taxes and policy instruments). In both scenarios EU's tradable CO 2 emission permits are included. Results from the study show that when national policies are included, the most cost-effective investment option is the bio CHP technology. However, when national taxes and policy instruments are excluded, the DH system containing the NGCC CHP plant has 30% lower system cost than the bio CHP system. Regardless of the scenario and when coal condensing is considered as marginal electricity production, the NGCC CHP has the largest global CO 2 reduction potential, about 300 ktonne CO 2 . However, the CO 2 reduction potential is highly dependent on the marginal electricity production. Demonstrated here is that national policies such as tradable green certificates can, when applied to DH systems, contribute to investments that will not fully utilise the DH systems' potential for global CO 2 emissions reductions. - Research highlights: →Swedish energy policies are promoting biomass fuelled electricity generating technologies over efficient fossil fuel electricity generating technologies. →An efficient fossil fuel technology like the natural gas combine cycle CHP technology with high power-to-heat ratio has potential to reduce the global CO 2 emissions more than a biomass fuelled electricity generating technology. →Swedish energy policies such as tradable green certificates for renewable electricity can, when applied to district heating systems, contribute to investments that will not fully utilise the district heating systems potential for

  18. Simultaneous Reduction of CO 2 and Splitting of H 2 O by a Single Immobilized Cobalt Phthalocyanine Electrocatalyst

    KAUST Repository

    Morlanes, Natalia Sanchez; Takanabe, Kazuhiro; Rodionov, Valentin

    2016-01-01

    Perfluorinated cobalt phthalocyanine (CoFPc) immobilized on carbon electrodes was found to electrocatalyze the reduction of CO2 selectively to CO in an aqueous solution. The conversion of CO2 became apparent at -0.5 V vs RHE, and the Faradaic

  19. Environmental Assessment for Potential Impacts of Ocean CO2 Storage on Marine Biogeochemical Cycles

    Science.gov (United States)

    Yamada, N.; Tsurushima, N.; Suzumura, M.; Shibamoto, Y.; Harada, K.

    2008-12-01

    Ocean CO2 storage that actively utilizes the ocean potential to dissolve extremely large amounts of CO2 is a useful option with the intent of diminishing atmospheric CO2 concentration. CO2 storage into sub-seabed geological formations is also considered as the option which has been already put to practical reconnaissance in some projects. Direct release of CO2 in the ocean storage and potential CO2 leakage from geological formations into the bottom water can alter carbonate system as well as pH of seawater. It is essential to examine to what direction and extent chemistry change of seawater induced by CO2 can affect the marine environments. Previous studies have shown direct and acute effects by increasing CO2 concentrations on physiology of marine organisms. It is also a serious concern that chemistry change can affect the rates of chemical, biochemical and microbial processes in seawater resulting in significant influences on marine biogeochemical cycles of the bioelements including carbon, nutrients and trace metals. We, AIST, have conducted a series of basic researches to assess the potential impacts of ocean CO2 storage on marine biogeochemical processes including CaCO3 dissolution, and bacterial and enzymatic decomposition of organic matter. By laboratory experiments using a special high pressure apparatus, the improved empirical equation was obtained for CaCO3 dissolution rate in the high CO2 concentrations. Based on the experimentally obtained kinetics with a numerical simulation for a practical scenario of oceanic CO2 sequestration where 50 Mton CO2 per year is continuously injected to 1,000-2,500 m depth within 100 x 333 km area for 30 years, we could illustrate precise 3-D maps for the predicted distributions of the saturation depth of CaCO3, in situ Ω value and CaCO3 dissolution rate in the western North Pacific. The result showed no significant change in the bathypelagic CaCO3 flux due to chemistry change induced by ocean CO2 sequestration. Both

  20. Potential for CO2 sequestration and Enhanced Coalbed Methane production in the Netherlands

    International Nuclear Information System (INIS)

    Hamelinck, C.N.; Faaij, A.P.C.; Ruijg, G.J.; Jansen, D.; Pagnier, H.; Van Bergen, F.; Wolf, K.H.; Barzandji, O.; Bruining, H.; Schreurs, H.

    2001-03-01

    The technical and economic feasibility of ECBM (Enhanced Coal Bed Methane) in the Netherlands are explored. The potential and the economic performance are worked out for several ECBM recovery concepts and technological issues are outlined. The research includes the following main activities: Inventory of CO2 sources in the Netherlands and techno-economic analysis of CO2 removal and transport. Several scenarios for CO2 transport of different capacities and distances will be assessed. ECBM production locations are determined by analysis of coal reserves and their characteristics. Four potential areas are assessed: one in eastern Gelderland, two in Limburg and one in Zeeland. Description of ECBM theory and production technology resulting in a time dependent model for ECBM production and CO2 injection. Selection and description of various ECBM production/CO2 sequestration systems. Systems considered include direct delivery of methane to the natural gas grid, production of power (on various scales) and hydrogen. Information from the location assessment is combined with modelling results. Costs of CO2 sequestration are calculated for various scales and configurations. Evaluation of main uncertainties, environmental impacts and sensitivity analyses. Comparison of CBM production systems with reference systems and exploration of potential implementation schemes in the Dutch context. 72 refs

  1. Potential of Russian Regions to Implement CO2-Enhanced Oil Recovery

    Directory of Open Access Journals (Sweden)

    Alexey Cherepovitsyn

    2018-06-01

    Full Text Available The paper assesses the techno-economic potential of Russia to implement carbon capture and storage technologies that imply the capture of anthropogenic CO2 and its injection into geologic reservoirs for long-term storage. The focus is on CO2 enhanced oil recovery projects that seem to be the most economically promising option of carbon capture and storage. The novelty of the work lies in the formulation of a potential assessment method of CO2 enhanced oil recovery, which allows for establishing a connection between energy production and oil extraction from the viewpoint of CO2 supply and demand. Using linear optimization, the most promising combinations of CO2 sources and sinks are identified and an economic evaluation of these projects is carried out. Based on this information, regions of Russia are ranked according to their prospects in regards to CO2 capture and enhanced oil recovery storage. The results indicate that Russia has a significant potential to utilize its power plants as CO2 sources for enhanced oil recovery projects. It has been estimated that 71 coal-fired power plants, and 185 of the gas-fired power plants of Russia annually produce 297.1 and 309.6 Mt of CO2 that can cover 553.4 Mt of the demand of 322 Russian oil fields. At the same time, the total CO2 storage capacity of the Russian fields is estimated at 7382.6 Mt, however, due to geological and technical factors, only 22.6% can be used for CO2-EOR projects. Of the 183 potential projects identified in the regional analysis phase, 99 were found to be cost-effective, with an average unit cost of € 19.07 per ton of CO2 and a payback period of 8.71 years. The most promising of the estimated regions is characterized by a well-developed energy industry, relatively low transportation costs, numerous large and medium-sized oil fields at the final stages of development, and favorable geological conditions that minimize the cost of injection. Geographically, they are located in the

  2. Environmental benefits from CO2 reduction, due to modal replacement: Case study on light rail vehicle in Brasilia City

    Energy Technology Data Exchange (ETDEWEB)

    Silva Costa, P.H. da; Alves Teixeira, L.M.; Cardoso Pinheiro, J.; Serra Arruda, F.; Mendonça Brasil, A.C.

    2016-07-01

    This work aims to measure the reduction of Carbon Dioxide (CO2) emissions in atmosphere by replacing the modal urban bus by Light Rail Vehicle (VLT). In order to accomplish this objective, a case study in Brasilia, Federal District, in the stretch of VLT which passes on Via W-3 South was conducted. The Theory of Externalities that discusses the right to ownership of private and public goods and responsibilities about the positive and negative externalities caused by the agents and individuals of society was used to support the analyses. It was used the Top-Down method, which allowed the calculation the direct emissions of CO2. The values obtained on the reduction of CO2 emissions were converted into values of carbon credits as a way to economically measure such reductions. The results showed a significant reduction in CO2 emissions per year and consequent environmental benefit. (Author)

  3. Oysters and eelgrass: potential partners in a high pCO2 ocean.

    Science.gov (United States)

    Groner, Maya L; Burge, Colleen A; Cox, Ruth; Rivlin, Natalie; Turner, Mo; Van Alstyne, Kathryn L; Wyllie-Echeverria, Sandy; Bucci, John; Staudigel, Philip; Friedman, Carolyn S

    2018-05-25

    Climate change is affecting the health and physiology of marine organisms and altering species interactions. Ocean acidification (OA) threatens calcifying organisms such as the Pacific oyster, Crassostrea gigas. In contrast, seagrasses, such as the eelgrass Zostera marina, can benefit from the increase in available carbon for photosynthesis found at a lower seawater pH. Seagrasses can remove dissolved inorganic carbon from OA environments, creating local daytime pH refugia. Pacific oysters may improve the health of eelgrass by filtering out pathogens such as Labyrinthula zosterae (LZ), which causes eelgrass wasting disease (EWD). We examined how co-culture of eelgrass ramets and juvenile oysters affected the health and growth of eelgrass and the mass of oysters under different pCO 2 exposures. In Phase I, each species was cultured alone or in co-culture at 12°C across ambient, medium, and high pCO 2 conditions, (656, 1158 and1606 μatm pCO 2 , respectively). Under high pCO 2 , eelgrass grew faster and had less severe EWD (contracted in the field prior to the experiment). Co-culture with oysters also reduced the severity of EWD. While the presence of eelgrass decreased daytime pCO 2 , this reduction was not substantial enough to ameliorate the negative impact of high pCO 2 on oyster mass. In Phase II, eelgrass alone or oysters and eelgrass in co-culture were held at 15°C under ambient and high pCO 2 conditions, (488 and 2013 μatm pCO 2 , respectively). Half of the replicates were challenged with cultured LZ. Concentrations of defensive compounds in eelgrass (total phenolics and tannins), were altered by LZ exposure and pCO 2 treatments. Greater pathogen loads and increased EWD severity were detected in LZ exposed eelgrass ramets; EWD severity was reduced at high relative to low pCO 2 . Oyster presence did not influence pathogen load or EWD severity; high LZ concentrations in experimental treatments may have masked the effect of this treatment. Collectively, these

  4. Willingness to engage in energy conservation and CO2 emissions reduction: An empirical investigation

    Science.gov (United States)

    Eluwa, S. E.; Siong, H. C.

    2014-02-01

    Africa's response to climate change has largely been focused on adaptation rather than mitigation. The reason for this is based on the fact that the continent contributes very little to global CO2 emission. Again, mitigation policies like carbon tax as being practised in developed countries may be costly and difficult to implement in a continent where most economies are fragile. Using behavioural change as an adaptation approach, we examined the opinion of Ibadan city residents towards energy conservation and CO2 emissions reduction. A total of 822 respondents were sampled across the three residential neighbourhoods of the city. Results from the study showed that female and male respondents differed in their opinion towards energy conservation. However, the female respondents tended to record higher mean scores on majority of the items used to capture energy conservation behaviour than their male counterparts. Also, those with higher level of education seemed to be more conscious of the environmental consequences arising from energy use at home than those with lower educational background. However, very slight variations were recorded in the mean value score across the different age groups, those respondents above 50 years scored a bit higher than other age groups.

  5. Scenarios in decision-making. An application to CO2 emission reduction strategies in passenger transport

    Energy Technology Data Exchange (ETDEWEB)

    Rienstra, S.A.; Vleugel, J.M; Nijkamp, P. [Department of Social Economics, Vrije Universiteit, Amsterdam (Netherlands)] Smokers, R.T.M. [ECN Policy Studies, Petten (Netherlands)

    1995-12-01

    The usefulness of scenarios for decision-makers is analyzed. First, a theoretical introduction to the scenario methodology is presented. Next, four energy scenarios for West-European passenger transport are developed. To start with, the present transport system as a baseline case is described and analysed. For each scenario it is outlined how the passenger transport system may look like in terms of the use of various existing and future transport technologies and the corresponding modal split. Expected energy consumption features of the various transport modes are described, data on the present fuel supply and electricity generation system are presented, as well as estimations of the future energy system. The energy consumption and CO2 emissions associated with the future passenger transport systems are assessed and these impacts are compared with the current system. The conclusion is that these scenarios provide interesting policy options for decision-makers. A large-scale reduction of CO2 emissions is possible in several ways, but each way will cause many problems, since drastic policy measures will have to be introduced, which may affect economic growth and the lifestyles of individuals. 5 figs., 11 tabs., 24 refs.

  6. Willingness to engage in energy conservation and CO2 emissions reduction: An empirical investigation

    International Nuclear Information System (INIS)

    Eluwa, S E; Siong, H C

    2014-01-01

    Africa's response to climate change has largely been focused on adaptation rather than mitigation. The reason for this is based on the fact that the continent contributes very little to global CO 2 emission. Again, mitigation policies like carbon tax as being practised in developed countries may be costly and difficult to implement in a continent where most economies are fragile. Using behavioural change as an adaptation approach, we examined the opinion of Ibadan city residents towards energy conservation and CO 2 emissions reduction. A total of 822 respondents were sampled across the three residential neighbourhoods of the city. Results from the study showed that female and male respondents differed in their opinion towards energy conservation. However, the female respondents tended to record higher mean scores on majority of the items used to capture energy conservation behaviour than their male counterparts. Also, those with higher level of education seemed to be more conscious of the environmental consequences arising from energy use at home than those with lower educational background. However, very slight variations were recorded in the mean value score across the different age groups, those respondents above 50 years scored a bit higher than other age groups

  7. Feasibility study on energy saving and reduction of CO2 emissions at Pertamina's Cilacap Refinery

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    With an objective of saving energy and reducing greenhouse gas emission, a basic survey has been performed on the atmospheric crude oil distillation units and the high vacuum distillation units at Cilacap Refinery in Indonesia. The first site survey in September 2000 has carried out a survey on the situation of the facilities and operation upon obtaining the facility data and operation information from Pertamina. As a result, it was revealed that there is a room of improvement in the heat recovery, whereas a modification design was executed on the improvement proposals on the heat exchanger system. However, the second site survey in November 2000 has revealed that Pertamina had executed in 1998 through 1999 the de-bottlenecking project on the crude oil atmospheric distillation units (two units) and the high vacuum distillation units (two units), by which the capability has been expanded, and the heat recovery rate has been increased. It is not possible to look for extremely large enhancement of the heat recovery rate beyond that point, and the reduction of CO2 emission would also be small. As a result of discussions, the present project was found capable of reducing annually the CO2 emission by 36,500 tons. (NEDO)

  8. Electrochemical Reduction of CO2 on Compositionally Variant Au-Pt Bimetallic Thin Films

    DEFF Research Database (Denmark)

    Ma, Ming; Hansen, Heine Anton; Valenti, Marco

    2017-01-01

    The electrocatalytic reduction of CO2 on Au-Pt bimetallic catalysts with different compositions was evaluated, offering a platform for uncovering the correlation between the catalytic activity and the surface composition of bimetallic electrocatalysts. The Au-Pt alloy films were synthesized...... by a magnetron sputtering co-deposition technique with tunable composition. It was found that the syngas ratio (CO:H2) on the Au-Pt films is able to be tuned by systematically controlling the binary composition. This tunable catalytic selectivity is attributed to the variation of binding strength of COOH and CO...... intermediates, influenced by the surface electronic structure (d-band center energy) which is linked to the surface composition of the bimetallic films. Notably, a gradual shift of the d-band center away from the Fermi level was observed with increasing Au content, which correspondingly reduces the binding...

  9. Southern Adriatic sea as a potential area for CO2 geological storage

    International Nuclear Information System (INIS)

    Volpi, V.; Forlin, F.; Donda, F.; Civile, D.; Facchin, L.; Sauli, L.; Merson, B.; Sinza-Mendieta, K.; Shams, A.

    2015-01-01

    The Southern Adriatic Sea is one of the five prospective areas for CO 2 storage being evaluated under the three year (FP7) European SiteChar project dedicated to the characterization of European CO 2 storage sites. The potential reservoir for CO 2 storage is represented by a carbonate formation, the wackstones and packstones of the Scaglia Formation (Upper Cretaceous-Paleogene). In this paper, we present the geological characterization and the 3D modeling that led to the identification of three sites, named Grazia, Rovesti and Grifone, where the Scaglia Formation, with an average thickness of 50 m, reveals good petrophysical characteristics and is overlain by an up to 1 200 thick cap-rock. The vicinity of the selected sites to the Enel - Federico II power plant (one of the major Italian CO 2 emitter) where a pilot plant for CO 2 capture has been already started in April 2010, represents a good opportunity to launch the first Carbon Capture and Storage (CCS) pilot project in Italy and to apply this technology at industrial level, strongly contributing at the same time at reducing the national CO 2 emissions. (authors)

  10. Potential for waste reduction

    International Nuclear Information System (INIS)

    Warren, J.L.

    1990-01-01

    The author focuses on wastes considered hazardous under the Resource Conservation and Recovery Act. This chapter discusses wastes that are of interest as well as the factors affecting the quantity of waste considered available for waste reduction. Estimates are provided of the quantities of wastes generated. Estimates of the potential for waste reduction are meaningful only to the extent that one can understand the amount of waste actually being generated. Estimates of waste reduction potential are summarized from a variety of government and nongovernment sources

  11. Environment and mobility 2050: scenarios for a 75% reduction in CO2 emissions

    International Nuclear Information System (INIS)

    Lopez-Ruiz, H.G.

    2009-10-01

    In France an objective of dividing greenhouse gas emissions by four, from the 1990 level, by 2050 has been set. Are these ambitions out of our reach? What will the price to pay for this objective be? We have built a long-term back-casting transport demand model (TILT, Transport Issues in the Long Term) . This model is centered on defined behavior types - in which the speed-GDP elasticity plays a key role - in order to determine demand estimations. This model lets us understand past tendencies - the coupling between growth and personal and freight mobility and adapt behavioral hypothesis - linked to the evolution of public policies - in order to show how a 75% reduction objective can be attained. The main results are an estimation of CO 2 emissions for the transport sector taking into account technical progress and demand. These results are presented as three scenario families named: Pegasus, Chronos and Hestia. Each family corresponds to a growing degree of constraint on mobility. It is possible to divide greenhouse gas emissions in the transport sector by four. Technical progress is able to lead to more than half of these reductions. The interest of these scenarios is to show that there exist different paths - through organizational change - to getting the other half of the reductions. (author)

  12. A simulation method for the rapid screening of potential depleted oil reservoirs for CO2 sequestration

    International Nuclear Information System (INIS)

    Bossie-Codreanu, D.; Le Gallo, Y.

    2004-01-01

    The reduction of greenhouse gases emission is a growing concern of many industries. The oil and gas industry has a long commercial practice of gas injection, enhanced oil recovery (EOR) and gas storage. Using a depleted oil or gas reservoir for CO 2 storage has several interesting advantages. The long-term risk analysis of the CO 2 behavior and its impact on the environment is a major concern. That is why the selection of an appropriate reservoir is crucial to the success of a sequestration operation. Our modeling study, based on a synthetic reservoir, quantifies uncertainties due to reservoir parameters in order to establish a set of guidelines to select the most appropriate depleted reservoirs. Several production and sequestration scenarios are investigated in order to quantify key parameter for CO 2 storage. The influence of parameters such as API gravity, heterogeneity (Dykstra-Parson coefficient), pressure support (water injection) and cap rock integrity are analyzed. Estimation of sequestration capacity is proposed through a sequestration factor (SF) estimated for different reservoir production drives. Multiple regression relationships were developed, allowing SF estimation. CO 2 sequestration optimization highlights the best clean oil recovery strategy (CO 2 injection and/or oil production)

  13. Potential for iron oxides to control metal releases in CO2 sequestration scenarios

    Science.gov (United States)

    Berger, P.M.; Roy, W.R.

    2011-01-01

    The potential for the release of metals into groundwater following the injection of carbon dioxide (CO2) into the subsurface during carbon sequestration projects remains an open research question. Changing the chemical composition of even the relatively deep formation brines during CO2 injection and storage may be of concern because of the recognized risks associated with the limited potential for leakage of CO2-impacted brine to the surface. Geochemical modeling allows for proactive evaluation of site geochemistry before CO2 injection takes place to predict whether the release of metals from iron oxides may occur in the reservoir. Geochemical modeling can also help evaluate potential changes in shallow aquifers were CO2 leakage to occur near the surface. In this study, we created three batch-reaction models that simulate chemical changes in groundwater resulting from the introduction of CO2 at two carbon sequestration sites operated by the Midwest Geological Sequestration Consortium (MGSC). In each of these models, we input the chemical composition of groundwater samples into React??, and equilibrated them with selected mineral phases and CO 2 at reservoir pressure and temperature. The model then simulated the kinetic reactions with other mineral phases over a period of up to 100 years. For two of the simulations, the water was also at equilibrium with iron oxide surface complexes. The first model simulated a recently completed enhanced oil recovery (EOR) project in south-central Illinois in which the MGSC injected into, and then produced CO2, from a sandstone oil reservoir. The MGSC afterwards periodically measured the brine chemistry from several wells in the reservoir for approximately two years. The sandstone contains a relatively small amount of iron oxide, and the batch simulation for the injection process showed detectable changes in several aqueous species that were attributable to changes in surface complexation sites. After using the batch reaction

  14. The Potential for Electrofuels Production in Sweden Utilizing Fossil and Biogenic CO2 Point Sources

    International Nuclear Information System (INIS)

    Hansson, Julia; Hackl, Roman; Taljegard, Maria; Brynolf, Selma; Grahn, Maria

    2017-01-01

    This paper maps, categorizes, and quantifies all major point sources of carbon dioxide (CO 2 ) emissions from industrial and combustion processes in Sweden. The paper also estimates the Swedish technical potential for electrofuels (power-to-gas/fuels) based on carbon capture and utilization. With our bottom-up approach using European databases, we find that Sweden emits approximately 50 million metric tons of CO 2 per year from different types of point sources, with 65% (or about 32 million tons) from biogenic sources. The major sources are the pulp and paper industry (46%), heat and power production (23%), and waste treatment and incineration (8%). Most of the CO 2 is emitted at low concentrations (<15%) from sources in the southern part of Sweden where power demand generally exceeds in-region supply. The potentially recoverable emissions from all the included point sources amount to 45 million tons. If all the recoverable CO 2 were used to produce electrofuels, the yield would correspond to 2–3 times the current Swedish demand for transportation fuels. The electricity required would correspond to about 3 times the current Swedish electricity supply. The current relatively few emission sources with high concentrations of CO 2 (>90%, biofuel operations) would yield electrofuels corresponding to approximately 2% of the current demand for transportation fuels (corresponding to 1.5–2 TWh/year). In a 2030 scenario with large-scale biofuels operations based on lignocellulosic feedstocks, the potential for electrofuels production from high-concentration sources increases to 8–11 TWh/year. Finally, renewable electricity and production costs, rather than CO 2 supply, limit the potential for production of electrofuels in Sweden.

  15. Preparation of Cu2O modified TiO2 nanopowder and its application to the visible light photoelectrocatalytic reduction of CO2 to CH3OH

    Science.gov (United States)

    Li, Bin; Niu, Wenchao; Cheng, Yongwei; Gu, Junjie; Ning, Ping; Guan, Qingqing

    2018-05-01

    Cu2O/TiO2 nanopowders were prepared and used as thin film electrode raw materials for CO2 photoelectroreduction. Characterization results from XRD, TEM, UV-Vis and BET show that Cu2O/TiO2 composites have regular morphology, narrow band gap, excellent textural properties, and exhibits marked response of visible light. The photoelectrocatalytic results show that CO2 can be reduced to formaldehyde (i.e., intermediate) and finally methanol (i.e., end product). In addition, the CO2 photoelectroreduction pathway and the mechanism of photoelectrocatalysis are discussed. In summary, the work reports a potential method of CO2 reduction by visible-light photocatalysis without an external bias.

  16. CO_2 emissions reduction of Chinese light manufacturing industries: A novel RAM-based global Malmquist–Luenberger productivity index

    International Nuclear Information System (INIS)

    Emrouznejad, Ali; Yang, Guo-liang

    2016-01-01

    Climate change has become one of the most challenging issues facing the world. Chinese government has realized the importance of energy conservation and prevention of the climate changes for sustainable development of China's economy and set targets for CO_2 emissions reduction in China. In China industry contributes 84.2% of the total CO_2 emissions, especially manufacturing industries. Data envelopment analysis (DEA) and Malmquist productivity (MP) index are the widely used mathematical techniques to address the relative efficiency and productivity of a group of homogenous decision making units, e.g. industries or countries. However, in many real applications, especially those related to energy efficiency, there are often undesirable outputs, e.g. the pollutions, waste and CO_2 emissions, which are produced inevitably with desirable outputs in the production. This paper introduces a novel Malmquist–Luenberger productivity (MLP) index based on directional distance function (DDF) to address the issue of productivity evolution of DMUs in the presence of undesirable outputs. The new RAM (Range-adjusted measure)-based global MLP index has been applied to evaluate CO_2 emissions reduction in Chinese light manufacturing industries. Recommendations for policy makers have been discussed. - Highlights: •CO_2 emissions reduction in Chinese light manufacturing industries are measured. •A novel RAM based Malmquist–Luenberger productivity index has been developed. •Recommendation to policy makers for reducing CO_2 reduction in China are given.

  17. Reduction of lumichrome by the radical anions of CO2 and lipoamide

    International Nuclear Information System (INIS)

    Ahmad, R.; Armstrong, D.A.

    1984-01-01

    The uptake of reducing equivalents of .CO 2 - by lumichrome in spectrophotometric titrations has been re-examined in the light of a recently reported extinction coefficient of 10 500 M -1 cm -1 at pH 6, which is in agreement with 10 270 +- 100 M -1 cm -1 determined here. The average uptake was 1.8 +- 0.1, independent of pH in the range 6.3-9.0. The major product appears to be a dihydro-alloxazine, which can be reoxidized quantitatively to lumichrome by .Br 2 - radicals or by O 2 . As in the case of dihydroflavins, oxidation by O 2 is biphasic. As in the case of flavins, a two electron reduction of lumichrome was also observed with the disulphide monoanion of lipoamide (LS. 2 - ), but that reduction does not go to 100 per cent yield. Contrary to our earlier conclusions, which were based on an erroneous extinction coefficient, the combination of lumichrome radicals (2.LcH→HLc-LcH) was of relatively little (< approx. 20 per cent) importance, and the behaviour of lumichrome on treatment with reducing species was rather similar to that of flavins. (author)

  18. Developments since 2005 in understanding potential environmental impacts of CO2 leakage from geological storage

    NARCIS (Netherlands)

    Jones, D.G.; Beaubien, S.E.; Blackford, J.C.; Foekema, E.M.; Lions, J.; Vittor, de C.; West, J.M.; Widdicombe, S.; Hauton, C.; Queiros, A.M.

    2015-01-01

    This paper reviews research into the potential environmental impacts of leakage from geological storage of CO2 since the publication of the IPCC Special Report on Carbon Dioxide Capture and Storage in 2005. Possible impacts are considered on onshore (including drinking water aquifers) and offshore

  19. Plant-soil distribution of potentially toxic elements in response to elevated atmospheric CO2.

    Science.gov (United States)

    Duval, Benjamin D; Dijkstra, Paul; Natali, Susan M; Megonigal, J Patrick; Ketterer, Michael E; Drake, Bert G; Lerdau, Manuel T; Gordon, Gwyneth; Anbar, Ariel D; Hungate, Bruce A

    2011-04-01

    The distribution of contaminant elements within ecosystems is an environmental concern because of these elements' potential toxicity to animals and plants and their ability to hinder microbial ecosystem services. As with nutrients, contaminants are cycled within and through ecosystems. Elevated atmospheric CO2 generally increases plant productivity and alters nutrient element cycling, but whether CO2 causes similar effects on the cycling of contaminant elements is unknown. Here we show that 11 years of experimental CO2 enrichment in a sandy soil with low organic matter content causes plants to accumulate contaminants in plant biomass, with declines in the extractable contaminant element pools in surface soils. These results indicate that CO2 alters the distribution of contaminant elements in ecosystems, with plant element accumulation and declining soil availability both likely explained by the CO2 stimulation of plant biomass. Our results highlight the interdependence of element cycles and the importance of taking a broad view of the periodic table when the effects of global environmental change on ecosystem biogeochemistry are considered.

  20. Inverse Modeling of Water-Rock-CO2 Batch Experiments: Potential Impacts on Groundwater Resources at Carbon Sequestration Sites.

    Science.gov (United States)

    Yang, Changbing; Dai, Zhenxue; Romanak, Katherine D; Hovorka, Susan D; Treviño, Ramón H

    2014-01-01

    This study developed a multicomponent geochemical model to interpret responses of water chemistry to introduction of CO2 into six water-rock batches with sedimentary samples collected from representative potable aquifers in the Gulf Coast area. The model simulated CO2 dissolution in groundwater, aqueous complexation, mineral reactions (dissolution/precipitation), and surface complexation on clay mineral surfaces. An inverse method was used to estimate mineral surface area, the key parameter for describing kinetic mineral reactions. Modeling results suggested that reductions in groundwater pH were more significant in the carbonate-poor aquifers than in the carbonate-rich aquifers, resulting in potential groundwater acidification. Modeled concentrations of major ions showed overall increasing trends, depending on mineralogy of the sediments, especially carbonate content. The geochemical model confirmed that mobilization of trace metals was caused likely by mineral dissolution and surface complexation on clay mineral surfaces. Although dissolved inorganic carbon and pH may be used as indicative parameters in potable aquifers, selection of geochemical parameters for CO2 leakage detection is site-specific and a stepwise procedure may be followed. A combined study of the geochemical models with the laboratory batch experiments improves our understanding of the mechanisms that dominate responses of water chemistry to CO2 leakage and also provides a frame of reference for designing monitoring strategy in potable aquifers.

  1. Estimating the CO2 mitigation potential of horizontal Ground Source Heat Pumps in the UK

    Science.gov (United States)

    Garcia-Gonzalez, R.; Verhoef, A.; Vidale, P. L.; Gan, G.; Chong, A.; Clark, D.

    2012-04-01

    By 2020, the UK will need to generate 15% of its energy from renewables to meet our contribution to the EU renewable energy target. Heating and cooling systems of buildings account for 30%-50% of the global energy consumption; thus, alternative low-carbon technologies such as horizontal Ground Couple Heat Pumps (GCHPs) can contribute to the reduction of anthropogenic CO2 emissions. Horizontal GCHPs currently represent a small fraction of the total energy generation in the UK. However, the fact that semi-detached and detached dwellings represent approximately 40% of the total housing stocks in the UK could make the widespread implementation of this technology particularly attractive in the UK and so could significantly increase its renewable energy generation potential. Using a simulation model, we analysed the dynamic interactions between the environment, the horizontal GCHP heat exchanger and typical UK dwellings, as well as their combined effect on heat pump performance and CO2 mitigation potential. For this purpose, a land surface model (JULES, Joint UK Land Environment Simulator), which calculates coupled soil heat and water fluxes, was combined with a heat extraction model. The analyses took into account the spatio-temporal variability of soil properties (thermal and hydraulic) and meteorological variables, as well as different horizontal GCHP configurations and a variety of building loads and heat demands. Sensitivity tests were performed for four sites in the UK with different climate and soil properties. Our results show that an installation depth of 1.0m would give us higher heat extractions rates, however it would be preferable to install the pipes slightly deeper to avoid the seasonal influence of variable meteorological conditions. A value of 1.5m for the spacing between coils (S) for a slinky configuration type is recommended to avoid thermal disturbances between neighbouring coils. We also found that for larger values of the spacing between the coils

  2. Potential impacts on groundwater resources of deep CO2 storage: natural analogues for assessing potential chemical effects

    Science.gov (United States)

    Lions, J.; Gale, I.; May, F.; Nygaard, E.; Ruetters, H.; Beaubien, S.; Sohrabi, M.; Hatzignatiou, D. G.; CO2GeoNet Members involved in the present study Team

    2011-12-01

    Carbon dioxide Capture and Storage (CCS) is considered as one of the promising options for reducing atmospheric emissions of CO2 related to human activities. One of the main concerns associated with the geological storage of CO2 is that the CO2 may leak from the intended storage formation, migrate to the near-surface environment and, eventually, escape from the ground. This is a concern because such leakage may affect aquifers overlying the storage site and containing freshwater that may be used for drinking, industry and agriculture. The IEA Greenhouse Gas R&D Programme (IEAGHG) recently commissioned the CO2GeoNet Association to undertake a review of published and unpublished literature on this topic with the aim of summarizing 'state of the art' knowledge and identifying knowledge gaps and research priorities in this field. Work carried out by various CO2GeoNet members was also used in this study. This study identifies possible areas of conflict by combining available datasets to map the global and regional superposition of deep saline formations (DSF) suitable for CO2 storage and overlying fresh groundwater resources. A scenario classification is developed for the various geological settings where conflict could occur. The study proposes two approaches to address the potential impact mechanisms of CO2 storage projects on the hydrodynamics and chemistry of shallow groundwater. The first classifies and synthesizes changes of water quality observed in natural/industrial analogues and in laboratory experiments. The second reviews hydrodynamic and geochemical models, including coupled multiphase flow and reactive transport. Various models are discussed in terms of their advantages and limitations, with conclusions on possible impacts on groundwater resources. Possible mitigation options to stop or control CO2 leakage are assessed. The effect of CO2 pressure in the host DSF and the potential effects on shallow aquifers are also examined. The study provides a review of

  3. A DFT-based genetic algorithm search for AuCu nanoalloy electrocatalysts for CO2 reduction

    DEFF Research Database (Denmark)

    Lysgaard, Steen; Mýrdal, Jón Steinar Garðarsson; Hansen, Heine Anton

    2015-01-01

    Using a DFT-based genetic algorithm (GA) approach, we have determined the most stable structure and stoichiometry of a 309-atom icosahedral AuCu nanoalloy, for potential use as an electrocatalyst for CO2 reduction. The identified core–shell nano-particle consists of a copper core interspersed....... This shows that the mixed Cu135@Au174 core–shell nanoalloy has a similar adsorption energy, for the most favorable site, as a pure gold nano-particle. Cu, however, has the effect of stabilizing the icosahedral structure because Au particles are easily distorted when adding adsorbates....... that it is possible to use the LCAO mode to obtain a realistic estimate of the molecular chemisorption energy for systems where the computation in normal grid mode is not computationally feasible. These corrections are employed when calculating adsorption energies on the Cu, Au and most stable mixed particles...

  4. Comparison of Dry Gas Seasonal Storage with CO2 Storage and Re-Use Potential

    OpenAIRE

    Killerud, Marie

    2013-01-01

    To make large-scale CO2 storage economic, many groups have proposed using CO2in EOR projects to create value for CO2 storage. However, CO2 EOR projectsgenerally require a large and variable supply of CO2 and consequently may requiretemporary storage of CO2 in geological formations. In order to store CO2 atoffshore sites as a source for CO2 EOR projects, the CO2 needs to be extractedfrom a storage site to a certain extent. Alternatively, CO2 EOR projects maybe developed alongside saline aquife...

  5. An Incentive-Based Solution of Sustainable Mobility for Economic Growth and CO2 Emissions Reduction

    Directory of Open Access Journals (Sweden)

    Manuel Herrador

    2015-05-01

    Full Text Available “Incentivized Sustainable Mobility” is a conceptual business model which involves four stakeholders: citizens, municipalities, commerce and mobility services. A platform named “ISUMO” (Incentivized Sustainable Mobility provides technological support to this business model, integrating a set of metaservices that unifies the existing ICTs of transportation plus a unique patented QR-based (Quick Response low-cost charging device for electric vehicles. Essentially, the system tracks and registers citizens’ transportation activities (anonymously and voluntarily and evaluates each through a scoring system while their ecological footprint is calculated. Afterwards, citizens are able to exchange their accumulated points for discount QR coupons, to be redeemed in the associated commerce in order to purchase their products or services. The breakthrough of this business model is that it enhances awareness of sustainable mobility practices, increasing their attractiveness as perceived by the stakeholders with diverse benefits; citizens (and indirectly, the municipalities initiate a new consumption pattern of “coupons culture” linked to sustainable mobility, the urban economy is stimulated, and the use of mobility services grows, providing a new business opportunity regarding electric vehicles. It is expected that continuous exploration of the model and implementation will contribute to sustainable social and economic development aiming at CO2 emissions reduction, headline targets of the Europe 2020 strategy.

  6. Geochemical monitoring for potential environmental impacts of geologic sequestration of CO2

    Science.gov (United States)

    Kharaka, Yousif K.; Cole, David R.; Thordsen, James J.; Gans, Kathleen D.; Thomas, Randal B.

    2013-01-01

    Carbon dioxide sequestration is now considered an important component of the portfolio of options for reducing greenhouse gas emissions to stabilize their atmospheric levels at values that would limit global temperature increases to the target of 2 °C by the end of the century (Pacala and Socolow 2004; IPCC 2005, 2007; Benson and Cook 2005; Benson and Cole 2008; IEA 2012; Romanak et al. 2013). Increased anthropogenic emissions of CO2 have raised its atmospheric concentrations from about 280 ppmv during pre-industrial times to ~400 ppmv today, and based on several defined scenarios, CO2 concentrations are projected to increase to values as high as 1100 ppmv by 2100 (White et al. 2003; IPCC 2005, 2007; EIA 2012; Global CCS Institute 2012). An atmospheric CO2 concentration of 450 ppmv is generally the accepted level that is needed to limit global temperature increases to the target of 2 °C by the end of the century. This temperature limit likely would moderate the adverse effects related to climate change that could include sea-level rise from the melting of alpine glaciers and continental ice sheets and from the ocean warming; increased frequency and intensity of wildfires, floods, droughts, and tropical storms; and changes in the amount, timing, and distribution of rain, snow, and runoff (IPCC 2007; Sundquist et al. 2009; IEA 2012). Rising atmospheric CO2 concentrations are also increasing the amount of CO2 dissolved in ocean water lowering its pH from 8.1 to 8.0, with potentially disruptive effects on coral reefs, plankton and marine ecosystems (Adams and Caldeira 2008; Schrag 2009; Sundquist et al. 2009). Sedimentary basins in general and deep saline aquifers in particular are being investigated as possible repositories for the large volumes of anthropogenic CO2 that must be sequestered to mitigate global warming and related climate changes (Hitchon 1996; Benson and Cole 2008; Verma and Warwick 2011).

  7. Reduction of CO2 emissions in houses of historic and visual importance

    NARCIS (Netherlands)

    Hal, van J.D.M. (Anke); Dulski, B.; Postel, A.M.

    2010-01-01

    According to the ‘Climate Programme’ the municipality of Amsterdam has the ambition to reduce the CO2 emissions within the city limits by 40% in the year 2025 compared to the year 1990. To realize this ambition substantial CO2 savings have to be realized at the 375,000 current houses in the city. A

  8. Reduction of CO2 Emissions in Houses of Historic and Visual Importance

    NARCIS (Netherlands)

    Van Hal, A.; Dulski, B.; Postel, A.M.

    2010-01-01

    According to the ‘Climate Programme’ the municipality of Amsterdam has the ambition to reduce the CO2 emissions within the city limits by 40% in the year 2025 compared to the year 1990. To realize this ambition substantial CO2 savings have to be realized at the 375,000 current houses in the city. A

  9. A highly selective copper-indium bimetallic electrocatalyst for the electrochemical reduction of aqueous CO2to CO

    KAUST Repository

    Rasul, Shahid

    2014-12-23

    The challenge in the electrochemical reduction of aqueous carbon dioxide is in designing a highly selective, energy-efficient, and non-precious-metal electrocatalyst that minimizes the competitive reduction of proton to form hydrogen during aqueous CO2 conversion. A non-noble metal electrocatalyst based on a copper-indium (Cu-In) alloy that selectively converts CO2 to CO with a low overpotential is reported. The electrochemical deposition of In on rough Cu surfaces led to Cu-In alloy surfaces. DFT calculations showed that the In preferentially located on the edge sites rather than on the corner or flat sites and that the d-electron nature of Cu remained almost intact, but adsorption properties of neighboring Cu was perturbed by the presence of In. This preparation of non-noble metal alloy electrodes for the reduction of CO2 provides guidelines for further improving electrocatalysis.

  10. Rhenium Complexes Based on 2-Pyridyl-1,2,3-triazole Ligands: A New Class of CO2 Reduction Catalysts.

    Science.gov (United States)

    Ching, H Y Vincent; Wang, Xia; He, Menglan; Perujo Holland, Noemi; Guillot, Régis; Slim, Cyrine; Griveau, Sophie; Bertrand, Hélène C; Policar, Clotilde; Bedioui, Fethi; Fontecave, Marc

    2017-03-06

    A series of [Re(N^N)(CO) 3 (X)] (N^N = diimine and X = halide) complexes based on 4-(2-pyridyl)-1,2,3-triazole (pyta) and 1-(2-pyridyl)-1,2,3-triazole (tapy) diimine ligands have been prepared and electrochemically characterized. The first ligand-based reduction process is shown to be highly sensitive to the nature of the isomer as well as to the substituents on the pyridyl ring, with the peak potential changing by up to 700 mV. The abilities of this class of complexes to catalyze the electroreduction and photoreduction of CO 2 were assessed for the first time. It is found that only Re pyta complexes that have a first reduction wave with a peak potential at ca. -1.7 V vs SCE are active, producing CO as the major product, together with small amounts of H 2 and formic acid. The catalytic wave that is observed in the CVs is enhanced by the addition of water or trifluoroethanol as a proton source. Long-term controlled potential electrolysis experiments gave total Faradaic yield close to 100%. In particular, functionalization of the triazolyl ring with a 2,4,6-tri-tert-butylphenyl group provided the catalyst with a remarkable stability.

  11. A Consideration on Service Business Model for Saving Energy and Reduction of CO2 Emissions Using Inverters

    Science.gov (United States)

    Kosaka, Michitaka; Yabutani, Takashi

    This paper considers the effectiveness of service business approach for reducing CO2 emission. “HDRIVE” is a service business using inverters to reduce energy consumption of motor drive. The business model of this service is changed for finding new opportunities of CO2 emission reduction by combining various factors such as financial service or long-term service contract. Risk analysis of this business model is very important for giving stable services to users for long term. HDRIVE business model is found to be suitable for this objective. This service can be applied to the industries such as chemical or steel industry effectively, where CO2 emission is very large, and has the possibility of creating new business considering CDM or trading CO2 emission right. The effectiveness of this approach is demonstrated through several examples in real business.

  12. Biochars as Potential Adsorbers of CH4, CO2 and H2S

    Directory of Open Access Journals (Sweden)

    Sumathi Sethupathi

    2017-01-01

    Full Text Available Methane gas, as one of the major biogases, is a potential source of renewable energy for power production. Biochar can be readily used to purify biogas contaminants such as H2S and CO2. This study assessed the adsorption of CH4, H2S, and CO2 onto four different types of biochars. The adsorption dynamics of biochars were investigated in a fixed-bed column, by determining the breakthrough curves and adsorption capacities of biochars. The physicochemical properties of biochars were considered to justify the adsorption performance. The results showed that CH4 was not adsorbed well by the subjected biochars whereas CO2 and H2S were successfully captured. The H2S and CO2 breakthrough capacity were related to both the surface adsorption and chemical reaction. The adsorption capacity was in the following order: perilla > soybean stover > Korean oak > Japanese oak biochars. The simultaneous adsorption also leads to a competition of sorption sites. Biochars are a promising material for the biogas purification industry.

  13. Soot and NOx simultaneous reduction by use of CO2 mixed fuel; Ekika CO2 yokai nenryo ni yoru diesel kikan no susu, NOx no doji teigen

    Energy Technology Data Exchange (ETDEWEB)

    Senda, J; Yokoyama, T; Ikeda, M; Fujimoto, H [Doshisha University, Kyoto (Japan); Ifuku, Y [Kubota Corp., Osaka (Japan)

    1997-10-01

    We propose the new fuel injection system by use of diesel fuel dissolved with CO2 to reduce both soot and NOx simultaneously. In this paper spray combustion characteristics of CO2 mixed fuel is reported. It is revealed that flame temperature and KL factor at the CO2 mixed fuel combustion are lower than at the only n-tridecane combustion due to separation or partly flashing of CO2component. And the result of exhaust gas measurement shows the capability that CO2 mixed fuel is able to reduce both soot and NOx simultaneously. 12 refs., 7 figs., 1 tab.

  14. Model-Based Assessment of the CO2 Sequestration Potential of Coastal Ocean Alkalinization

    Science.gov (United States)

    Feng, E. Y.; Koeve, W.; Keller, D. P.; Oschlies, A.

    2017-12-01

    The potential of coastal ocean alkalinization (COA), a carbon dioxide removal (CDR) climate engineering strategy that chemically increases ocean carbon uptake and storage, is investigated with an Earth system model of intermediate complexity. The CDR potential and possible environmental side effects are estimated for various COA deployment scenarios, assuming olivine as the alkalinity source in ice-free coastal waters (about 8.6% of the global ocean's surface area), with dissolution rates being a function of grain size, ambient seawater temperature, and pH. Our results indicate that for a large-enough olivine deployment of small-enough grain sizes (10 µm), atmospheric CO2 could be reduced by more than 800 GtC by the year 2100. However, COA with coarse olivine grains (1000 µm) has little CO2 sequestration potential on this time scale. Ambitious CDR with fine olivine grains would increase coastal aragonite saturation Ω to levels well beyond those that are currently observed. When imposing upper limits for aragonite saturation levels (Ωlim) in the grid boxes subject to COA (Ωlim = 3.4 and 9 chosen as examples), COA still has the potential to reduce atmospheric CO2 by 265 GtC (Ωlim = 3.4) to 790 GtC (Ωlim = 9) and increase ocean carbon storage by 290 Gt (Ωlim = 3.4) to 913 Gt (Ωlim = 9) by year 2100.

  15. Developments in greenhouse gas emissions and net energy use in Danish agriculture - How to achieve substantial CO2 reductions?

    International Nuclear Information System (INIS)

    Dalgaard, T.; Olesen, J.E.; Petersen, S.O.; Petersen, B.M.; Jorgensen, U.; Kristensen, T.; Hutchings, N.J.; Gyldenkaerne, S.; Hermansen, J.E.

    2011-01-01

    Greenhouse gas (GHG) emissions from agriculture are a significant contributor to total Danish emissions. Consequently, much effort is currently given to the exploration of potential strategies to reduce agricultural emissions. This paper presents results from a study estimating agricultural GHG emissions in the form of methane, nitrous oxide and carbon dioxide (including carbon sources and sinks, and the impact of energy consumption/bioenergy production) from Danish agriculture in the years 1990-2010. An analysis of possible measures to reduce the GHG emissions indicated that a 50-70% reduction of agricultural emissions by 2050 relative to 1990 is achievable, including mitigation measures in relation to the handling of manure and fertilisers, optimization of animal feeding, cropping practices, and land use changes with more organic farming, afforestation and energy crops. In addition, the bioenergy production may be increased significantly without reducing the food production, whereby Danish agriculture could achieve a positive energy balance. - Highlights: → GHG emissions from Danish agriculture 1990-2010 are calculated, including carbon sequestration. → Effects of measures to further reduce GHG emissions are listed. → Land use scenarios for a substantially reduced GHG emission by 2050 are presented. → A 50-70% reduction of agricultural emissions by 2050 relative to 1990 is achievable. → Via bioenergy production Danish agriculture could achieve a positive energy balance. - Scenario studies of greenhouse gas mitigation measures illustrate the possible realization of CO 2 reductions for Danish agriculture by 2050, sustaining current food production.

  16. Role of the adsorbed oxygen species in the selective electrochemical reduction of CO_2 to alcohols and carbonyls on copper electrodes

    International Nuclear Information System (INIS)

    Le Duff, Cecile S.; Lawrence, Matthew J.; Rodriguez, Paramaconi

    2017-01-01

    The electrochemical reduction of CO_2 into fuels has gained significant attention recently as source of renewable carbon-based fuels. The unique high selectivity of copper in the electrochemical reduction of CO_2 to hydrocarbons has called much interest in discovering its mechanism. In order to provide significant information about the role of oxygen in the electrochemical reduction of CO_2 on Cu electrodes, the conditions of the surface structure and the composition of the Cu single crystal electrodes were controlled over time. This was achieved using pulsed voltammetry, since the pulse sequence can be programmed to guarantee reproducible initial conditions for the reaction at every fraction of time and at a given frequency. In contrast to the selectivity of CO_2 reduction using cyclic voltammetry and chronoamperometric methods, a large selection of oxygenated hydrocarbons was found under alternating voltage conditions. Product selectivity towards the formation of oxygenated hydrocarbon was associated to the coverage of oxygen species, which is surface-structure- and potential-dependent. (copyright 2017 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  17. Analysis of CO2, CO and HC emission reduction in automobiles

    Science.gov (United States)

    Balan, K. N.; Valarmathi, T. N.; Reddy, Mannem Soma Harish; Aravinda Reddy, Gireddy; Sai Srinivas, Jammalamadaka K. M. K.; Vasan

    2017-05-01

    In the present scenario, the emission from automobiles is becoming a serious problem to the environment. Automobiles, thermal power stations and Industries majorly constitute to the emission of CO2, CO and HC. Though the CO2 available in the atmosphere will be captured by oceans, grasslands; they are not enough to control CO2 present in the atmosphere completely. Also advances in engine and vehicle technology continuously to reduce the emission from engine exhaust are not sufficient to reduce the HC and CO emission. This work concentrates on design, fabrication and analysis to reduce CO2, CO and HC emission from exhaust of automobiles by using molecular sieve 5A of 1.5mm. In this paper, the details of the fabrication, results and discussion about the process are discussed.

  18. Recent Advances in Transition-Metal-Mediated Electrocatalytic CO2 Reduction: From Homogeneous to Heterogeneous Systems

    KAUST Repository

    Feng, Da-Ming; Zhu, Yun-Pei; Chen, Ping; Ma, Tian-Yi

    2017-01-01

    Global climate change and increasing demands for clean energy have brought intensive interest in the search for proper electrocatalysts in order to reduce carbon dioxide (CO2) to higher value carbon products such as hydrocarbons. Recently

  19. The development of the tertiary sector in the economy and the reduction in CO2 emissions

    International Nuclear Information System (INIS)

    Morvan, R.; Hubert, M.; Gregoire, P.; Lowezanin, Ch.

    2004-09-01

    The development of the tertiary sector appears to support sustainable development since it now accounts for almost two thirds of the national economy and is responsible for low CO 2 emission levels. Between 1980 and 1997, CO 2 emissions from the tertiary sector increased by 20 % compared with a 48 % rise in the sector value added. In terms of production, CO 2 levels in the tertiary sector are low, compared with 55 % for the secondary sector (industry). However, when trade between economic activities is taken into account, there is cause to qualify the assessment. This makes it possible to ascertain emissions from the point of view of satisfying final demand for products, and to identify direct and indirect emissions in each branch of activity. Thus, when emissions from certain industrial and agricultural activities are redistributed specifically to branches of activity in the tertiary sector, CO 2 emissions in this sector account for almost one-third of total emissions. (A.L.B.)

  20. Hot Hole Collection and Photoelectrochemical CO2 Reduction with Plasmonic Au/p-GaN Photocathodes.

    Science.gov (United States)

    DuChene, Joseph S; Tagliabue, Giulia; Welch, Alex J; Cheng, Wen-Hui; Atwater, Harry A

    2018-04-11

    Harvesting nonequilibrium hot carriers from plasmonic-metal nanostructures offers unique opportunities for driving photochemical reactions at the nanoscale. Despite numerous examples of hot electron-driven processes, the realization of plasmonic systems capable of harvesting hot holes from metal nanostructures has eluded the nascent field of plasmonic photocatalysis. Here, we fabricate gold/p-type gallium nitride (Au/p-GaN) Schottky junctions tailored for photoelectrochemical studies of plasmon-induced hot-hole capture and conversion. Despite the presence of an interfacial Schottky barrier to hot-hole injection of more than 1 eV across the Au/p-GaN heterojunction, plasmonic Au/p-GaN photocathodes exhibit photoelectrochemical properties consistent with the injection of hot holes from Au nanoparticles into p-GaN upon plasmon excitation. The photocurrent action spectrum of the plasmonic photocathodes faithfully follows the surface plasmon resonance absorption spectrum of the Au nanoparticles and open-circuit voltage studies demonstrate a sustained photovoltage during plasmon excitation. Comparison with Ohmic Au/p-NiO heterojunctions confirms that the vast majority of hot holes generated via interband transitions in Au are sufficiently hot to inject above the 1.1 eV interfacial Schottky barrier at the Au/p-GaN heterojunction. We further investigated plasmon-driven photoelectrochemical CO 2 reduction with the Au/p-GaN photocathodes and observed improved selectivity for CO production over H 2 evolution in aqueous electrolytes. Taken together, our results offer experimental validation of photoexcited hot holes more than 1 eV below the Au Fermi level and demonstrate a photoelectrochemical platform for harvesting hot carriers to drive solar-to-fuel energy conversion.

  1. On the Assessment of the CO2 Mitigation Potential of Woody Biomass

    Directory of Open Access Journals (Sweden)

    Víctor Codina Gironès

    2018-01-01

    Full Text Available Woody biomass, a renewable energy resource, accumulates solar energy in form of carbon hydrates produced from atmospheric CO2 and H2O. It is, therefore, a means of CO2 mitigation for society as long as the biogenic carbon released to the atmosphere when delivering its energy content by oxidation can be accumulated again during growth of new woody biomass. Even when considering the complete life cycle, usually, only a small amount of fossil CO2 is emitted. However, woody biomass availability is limited by land requirement and, therefore, it is important to maximize its CO2 mitigation potential in the energy system. In this study, we consider woody biomass not only as a source of renewable energy but also as a source of carbon for seasonal storage of solar electricity. A first analysis is carried out based on the mitigation effect of woody biomass usage pathways, which is the avoided fossil CO2 emissions obtained by using one unit of woody biomass to provide energy services, as alternative to fossil fuels. Results show that woody biomass usage pathways can achieve up to 9.55 times the mitigation effect obtained through combustion of woody biomass, which is taken as a reference. Applying energy system modeling and multi-objective optimization techniques, the role of woody biomass technological choices in the energy transition is then analyzed at a country scale. The analysis is applied to Switzerland, demonstrating that the use of woody biomass in gasification–methanation systems, coupled with electrolysers and combined with an intensive deployment of PV panels and efficient technologies, could reduce the natural gas imports to zero. Electrolysers are used to boost synthetic natural gas production by hydrogen injection into the methanation reaction. The hydrogen used is produced when there is excess of solar electricity. The efficient technologies, such as heat pumps and battery electric vehicles, allow increasing the overall efficiency of the

  2. The potential of blue energy for reducing emissions of CO2 and non-CO2 greenhouse gases

    NARCIS (Netherlands)

    Kuleszo, J.; Kroeze, C.; Post, J.; Fekete, B.M.

    2010-01-01

    Salinity gradient power (or blue energy) is a renewable energy source mentioned in the literature since the 1950s. It refers to the production of electricity by mixing of two solutions with different salt concentrations, for example river and sea water. The global potential of salinity power has

  3. The potential of satellite spectro-imagery for monitoring CO2 emissions from large cities

    Directory of Open Access Journals (Sweden)

    G. Broquet

    2018-02-01

    Full Text Available This study assesses the potential of 2 to 10 km resolution imagery of CO2 concentrations retrieved from the shortwave infrared measurements of a space-borne passive spectrometer for monitoring the spatially integrated emissions from the Paris area. Such imagery could be provided by missions similar to CarbonSat, which was studied as a candidate Earth Explorer 8 mission by the European Space Agency (ESA. This assessment is based on observing system simulation experiments (OSSEs with an atmospheric inversion approach at city scale. The inversion system solves for hourly city CO2 emissions and natural fluxes, or for these fluxes per main anthropogenic sector or ecosystem, during the 6 h before a given satellite overpass. These 6 h correspond to the period during which emissions produce CO2 plumes that can be identified on the image from this overpass. The statistical framework of the inversion accounts for the existence of some prior knowledge with 50 % uncertainty on the hourly or sectorial emissions, and with ∼ 25 % uncertainty on the 6 h mean emissions, from an inventory based on energy use and carbon fuel consumption statistics. The link between the hourly or sectorial emissions and the vertically integrated column of CO2 observed by the satellite is simulated using a coupled flux and atmospheric transport model. This coupled model is built with the information on the spatial and temporal distribution of emissions from the emission inventory produced by the local air-quality agency (Airparif and a 2 km horizontal resolution atmospheric transport model. Tests are conducted for different realistic simulations of the spatial coverage, resolution, precision and accuracy of the imagery from sun-synchronous polar-orbiting missions, corresponding to the specifications of CarbonSat and Sentinel-5 or extrapolated from these specifications. First, OSSEs are conducted with a rather optimistic configuration in which the inversion system

  4. The potential of satellite spectro-imagery for monitoring CO2 emissions from large cities

    Science.gov (United States)

    Broquet, Grégoire; Bréon, François-Marie; Renault, Emmanuel; Buchwitz, Michael; Reuter, Maximilian; Bovensmann, Heinrich; Chevallier, Frédéric; Wu, Lin; Ciais, Philippe

    2018-02-01

    This study assesses the potential of 2 to 10 km resolution imagery of CO2 concentrations retrieved from the shortwave infrared measurements of a space-borne passive spectrometer for monitoring the spatially integrated emissions from the Paris area. Such imagery could be provided by missions similar to CarbonSat, which was studied as a candidate Earth Explorer 8 mission by the European Space Agency (ESA). This assessment is based on observing system simulation experiments (OSSEs) with an atmospheric inversion approach at city scale. The inversion system solves for hourly city CO2 emissions and natural fluxes, or for these fluxes per main anthropogenic sector or ecosystem, during the 6 h before a given satellite overpass. These 6 h correspond to the period during which emissions produce CO2 plumes that can be identified on the image from this overpass. The statistical framework of the inversion accounts for the existence of some prior knowledge with 50 % uncertainty on the hourly or sectorial emissions, and with ˜ 25 % uncertainty on the 6 h mean emissions, from an inventory based on energy use and carbon fuel consumption statistics. The link between the hourly or sectorial emissions and the vertically integrated column of CO2 observed by the satellite is simulated using a coupled flux and atmospheric transport model. This coupled model is built with the information on the spatial and temporal distribution of emissions from the emission inventory produced by the local air-quality agency (Airparif) and a 2 km horizontal resolution atmospheric transport model. Tests are conducted for different realistic simulations of the spatial coverage, resolution, precision and accuracy of the imagery from sun-synchronous polar-orbiting missions, corresponding to the specifications of CarbonSat and Sentinel-5 or extrapolated from these specifications. First, OSSEs are conducted with a rather optimistic configuration in which the inversion system is perfectly informed about the

  5. Enhanced electrocatalysis performance of amorphous electrolytic carbon from CO2 for oxygen reduction by surface modification in molten salt

    International Nuclear Information System (INIS)

    Chen, Zhigang; Gu, Yuxing; Du, Kaifa; Wang, Xu; Xiao, Wei; Mao, Xuhui; Wang, Dihua

    2017-01-01

    Highlights: •The potential of electrolytic carbon as catalyst for oxygen reduction was evaluated. •A molten salt method for electrolytic-carbon modification was demonstrated. •The electrolytic carbon was activated for the ORR by the molten salt sulfidation. •Sulfur and cobalt dual modification further improved the ORR activity of the carbon. -- Abstract: The electrolytic carbon (E-carbon) derived from greenhouse gas CO 2 in molten carbonates at mild temperature possesses high electrical conductivity and suitable specific surface area. In this work, its potential as catalyst is investigated towards oxygen reduction reaction (ORR). It is revealed that the pristine E-carbon has no electrocatalytic activity for the ORR due to its high surface content of carboxyl group. The carbon was then treated in a Li 2 SO 4 containing Li 2 CO 3 -Na 2 CO 3 -K 2 CO 3 molten salt at 550 °C. Sulfur modified E-carbon was obtained in the melt via a galvanic sulfidation reaction, in which Li 2 SO 4 served as a nontoxic sulfur source and an oxidant. The sulfur modified E-carbon showed a significantly improved electrocatalytic activity. Subsequently, a sulfur/cobalt dual modified carbon with much higher catalysis activity was successfully prepared by treating an E-carbon/CoSO 4 composite in the same melt. The dual modified E-carbon showed excellent catalytic performance with activity close to the commercial Pt/C catalyst but a high tolerance towards methanol.

  6. Densely Packed, Ultra Small SnO Nanoparticles for Enhanced Activity and Selectivity in Electrochemical CO2 Reduction.

    Science.gov (United States)

    Gu, Jun; Héroguel, Florent; Luterbacher, Jeremy; Hu, Xile

    2018-03-05

    Controlling the selectivity in electrochemical CO 2 reduction is an unsolved challenge. While tin (Sn) has emerged as a promising non-precious catalyst for CO 2 electroreduction, most Sn-based catalysts produce formate as the major product, which is less desirable than CO in terms of separation and further use. Tin monoxide (SnO) nanoparticles supported on carbon black were synthesized and assembled and their application in CO 2 reduction was studied. Remarkably high selectivity and partial current densities for CO formation were obtained using these SnO nanoparticles compared to other Sn catalysts. The high activity is attributed to the ultra-small size of the nanoparticles (2.6 nm), while the high selectivity is attributed to a local pH effect arising from the dense packing of nanoparticles in the conductive carbon black matrix. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Geochemical modelling of worst-case leakage scenarios at potential CO2-storage sites - CO2 and saline water contamination of drinking water aquifers

    Science.gov (United States)

    Szabó, Zsuzsanna; Edit Gál, Nóra; Kun, Éva; Szőcs, Teodóra; Falus, György

    2017-04-01

    Carbon Capture and Storage is a transitional technology to reduce greenhouse gas emissions and to mitigate climate change. Following the implementation and enforcement of the 2009/31/EC Directive in the Hungarian legislation, the Geological and Geophysical Institute of Hungary is required to evaluate the potential CO2 geological storage structures of the country. Basic assessment of these saline water formations has been already performed and the present goal is to extend the studies to the whole of the storage complex and consider the protection of fresh water aquifers of the neighbouring area even in unlikely scenarios when CO2 injection has a much more regional effect than planned. In this work, worst-case scenarios are modelled to understand the effects of CO2 or saline water leaks into drinking water aquifers. The dissolution of CO2 may significantly change the pH of fresh water which induces mineral dissolution and precipitation in the aquifer and therefore, changes in solution composition and even rock porosity. Mobilization of heavy metals may also be of concern. Brine migration from CO2 reservoir and replacement of fresh water in the shallower aquifer may happen due to pressure increase as a consequence of CO2 injection. The saline water causes changes in solution composition which may also induce mineral reactions. The modelling of the above scenarios has happened at several methodological levels such as equilibrium batch, kinetic batch and kinetic reactive transport simulations. All of these have been performed by PHREEQC using the PHREEQC.DAT thermodynamic database. Kinetic models use equations and kinetic rate parameters from the USGS report of Palandri and Kharaka (2004). Reactive transport modelling also considers estimated fluid flow and dispersivity of the studied formation. Further input parameters are the rock and the original ground water compositions of the aquifers and a range of gas-phase CO2 or brine replacement ratios. Worst-case scenarios

  8. Continental-scale enrichment of atmospheric 14CO2 from the nuclear power industry: potential impact on the estimation of fossil fuel-derived CO2

    Science.gov (United States)

    Graven, H. D.; Gruber, N.

    2011-12-01

    The 14C-free fossil carbon added to atmospheric CO2 by combustion dilutes the atmospheric 14C/C ratio (Δ14C), potentially providing a means to verify fossil CO2 emissions calculated using economic inventories. However, sources of 14C from nuclear power generation and spent fuel reprocessing can counteract this dilution and may bias 14C/C-based estimates of fossil fuel-derived CO2 if these nuclear influences are not correctly accounted for. Previous studies have examined nuclear influences on local scales, but the potential for continental-scale influences on Δ14C has not yet been explored. We estimate annual 14C emissions from each nuclear site in the world and conduct an Eulerian transport modeling study to investigate the continental-scale, steady-state gradients of Δ14C caused by nuclear activities and fossil fuel combustion. Over large regions of Europe, North America and East Asia, nuclear enrichment may offset at least 20% of the fossil fuel dilution in Δ14C, corresponding to potential biases of more than -0.25 ppm in the CO2 attributed to fossil fuel emissions, larger than the bias from plant and soil respiration in some areas. Model grid cells including high 14C-release reactors or fuel reprocessing sites showed much larger nuclear enrichment, despite the coarse model resolution of 1.8°×1.8°. The recent growth of nuclear 14C emissions increased the potential nuclear bias over 1985-2005, suggesting that changing nuclear activities may complicate the use of Δ14C observations to identify trends in fossil fuel emissions. The magnitude of the potential nuclear bias is largely independent of the choice of reference station in the context of continental-scale Eulerian transport and inversion studies, but could potentially be reduced by an appropriate choice of reference station in the context of local-scale assessments.

  9. Review of CO2 Reduction Technologies using Mineral Carbonation of Iron and Steel Making Slag in Malaysia

    Science.gov (United States)

    Norhana Selamat, Siti; Nor, Nik Hisyamudin Muhd; Rashid, Muhammad Hanif Abdul; Fauzi Ahmad, Mohd; Mohamad, Fariza; Ismail, Al Emran; Fahrul Hassan, Mohd; Turan, Faiz Mohd; Zain, Mohd Zamzuri Mohd; Abu Bakar, Elmi; Seiji, Yokoyama

    2017-10-01

    Climate change, greenhouse gas effect, and global warming is envisioning to turn more awful and more terrible by year. Since the leading cause of global warming is uncontrolled CO2 in atmosphere. The amount of unused steel slag is expected to increment later on, steel industries is one of the mechanical industries that contribute the CO2 emission. That because this businesses deliver carbon in light of powers reductant and substantial volume of steel. The changes of atmosphere these day is truly developing concern and that make steel creator are confronted with test of discovering methods for bringing down CO2 emission. Malaysia is working decidedly in the diminishment of CO2 gas. There are a few techniques in decreasing the amount of CO2 in the air as underlined by the Intergovernmental Panel of Climate Change (IPCC), an organization under the United Country however CCS is an extremely encouraging innovation to moderate CO2 emission in air. Mineral carbonation is another technique to store carbon dioxide permanently, long term stability and vast capacity.

  10. Selective Reduction of CO2 to CH4 by Tandem Hydrosilylation with Mixed Al/B Catalysts

    KAUST Repository

    Chen, Jiawei

    2016-04-04

    This contribution reports the first example of highly selective reduction of CO2 into CH4 via tandem hydrosilylation with mixed main-group organo-Lewis acid (LA) catalysts [Al(C6F5)3 + B(C6F5)3] {[Al] + [B]}. As shown by this comprehensive experimental and computational study, in this unique tandem catalytic process, [Al] effectively mediates the first step of the overall reduction cycle, namely the fixation of CO2 into HCOOSiEt3 (1) via the LA-mediated C=O activation, while [B] is incapable of promoting the same transformation. On the other hand, [B] is shown to be an excellent catalyst for the subsequent reduction steps 2–4, namely the hydrosilylation of the more basic intermediates [1 to H2C(OSiEt3)2 (2) to H3COSiEt3 (3) and finally to CH4] through the frustrated-Lewis-pair (FLP)-type Si–H activation. Hence, with the required combination of [Al] and [B], a highly selective hydrosilylative reduction of CO2 system has been developed, achieving high CH4 production yield up to 94%. The remarkably different catalytic behaviors between [Al] and [B] are attributed to the higher overall Lewis acidity of [Al] derived from two conflicting factors (electronic and steric effects), which renders the higher tendency of [Al] to form stable [Al]–substrate (intermediate) adducts with CO2 as well as subsequent intermediates 1, 2 and 3. Overall, the roles of [Al] and [B] are not only complementary but also synergistic in the total reduction of CO2, which render both [Al]-mediated first reduction step and [B]-mediated subsequent steps catalytic.

  11. Selective Reduction of CO2 to CH4 by Tandem Hydrosilylation with Mixed Al/B Catalysts

    KAUST Repository

    Chen, Jiawei; Falivene, Laura; Caporaso, Lucia; Cavallo, Luigi; Chen, Eugene Y.-X.

    2016-01-01

    This contribution reports the first example of highly selective reduction of CO2 into CH4 via tandem hydrosilylation with mixed main-group organo-Lewis acid (LA) catalysts [Al(C6F5)3 + B(C6F5)3] {[Al] + [B]}. As shown by this comprehensive experimental and computational study, in this unique tandem catalytic process, [Al] effectively mediates the first step of the overall reduction cycle, namely the fixation of CO2 into HCOOSiEt3 (1) via the LA-mediated C=O activation, while [B] is incapable of promoting the same transformation. On the other hand, [B] is shown to be an excellent catalyst for the subsequent reduction steps 2–4, namely the hydrosilylation of the more basic intermediates [1 to H2C(OSiEt3)2 (2) to H3COSiEt3 (3) and finally to CH4] through the frustrated-Lewis-pair (FLP)-type Si–H activation. Hence, with the required combination of [Al] and [B], a highly selective hydrosilylative reduction of CO2 system has been developed, achieving high CH4 production yield up to 94%. The remarkably different catalytic behaviors between [Al] and [B] are attributed to the higher overall Lewis acidity of [Al] derived from two conflicting factors (electronic and steric effects), which renders the higher tendency of [Al] to form stable [Al]–substrate (intermediate) adducts with CO2 as well as subsequent intermediates 1, 2 and 3. Overall, the roles of [Al] and [B] are not only complementary but also synergistic in the total reduction of CO2, which render both [Al]-mediated first reduction step and [B]-mediated subsequent steps catalytic.

  12. Chinese Public’s Willingness to Pay for CO2 Emissions Reductions: A Case Study from Four Provinces/Cities

    Directory of Open Access Journals (Sweden)

    Duan Hong-Xia

    2014-01-01

    Citation: Duan, H.-X., Lü, Y.-L., Li, Y., 2014. Chinese public’s willingness to pay for CO2 emissions reductions: A case study from four provinces/cities. Adv. Clim. Change Res. 5(2, doi: 10.3724/SP.J.1248.2014.100.

  13. Problem shifting in transport systems. Analysing and balancing unintended consequences of CO2 emission reduction in Dutch transport.

    NARCIS (Netherlands)

    Gebler, Malte

    2013-01-01

    Summary Transport systems face significant input- and output-related challenges in the upcoming decades. To tackle climate change – the major output challenge - an 80% CO2 reduction has to be achieved by 2050 (base year 1990). This requires a sustainabi

  14. Potentials and challenges associated with automated closed dynamic chamber measurements of soil CO2 fluxes

    Science.gov (United States)

    Görres, Carolyn-Monika; Kammann, Claudia; Ceulemans, Reinhart

    2015-04-01

    Soil respiration fluxes are influenced by natural factors such as climate and soil type, but also by anthropogenic activities in managed ecosystems. As a result, soil CO2 fluxes show a large intra- and interannual as well as intra- and intersite variability. Most of the available soil CO2 flux data giving insights into this variability have been measured with manually closed static chambers, but technological advances in the past 15 years have also led to an increased use of automated closed chamber systems. The great advantage of automated chambers in comparison to manually operated chambers is the higher temporal resolution of the flux data. This is especially important if we want to better understand the effects of short-term events, e.g. fertilization or heavy rainfall, on soil CO2 flux variability. However, the chamber method is an invasive measurement method which can potentially alter soil CO2 fluxes and lead to biased measurement results. In the peer-reviewed literature, many papers compare the field performance and results of different closed static chamber designs, or compare manual chambers with automated chamber systems, to identify potential biases in CO2 flux measurements, and thus help to reduce uncertainties in the flux data. However, inter-comparisons of different automated closed dynamic chamber systems are still lacking. Here we are going to present a field comparison of the most-cited automated chamber system, the LI-8100A Automated Soil Flux System, with the also commercially available Greenhouse Gas Monitoring System AGPS. Both measurement systems were installed side by side at a recently harvested poplar bioenergy plantation (POPFULL, http://uahost.uantwerpen.be/popfull/) from April 2014 until August 2014. The plantation provided optimal comparison conditions with a bare field situation after the harvest and a regrowing canopy resulting in a broad variety of microclimates. Furthermore, the plantation was planted in a double-row system with

  15. CO2 abatement potential of wood utilisation. Wood as an energy carrier

    International Nuclear Information System (INIS)

    Wegener, G.; Fruehwald, A.

    1994-01-01

    Forests as ecosystems not only supply the raw material wood but also exert an influence on soils, water resources and many other ecological factors; provide animals with a habitat; and offer as humans a place for recreation. Recently, forests and wood have become of interest to human civilisation from yet another aspect: they constitute a carbon storage. This means that forestry and the forest industries can help moderate the increase of atmospheric CO 2 concentrations, which is essentially the result of energetic utilisation of fossil fuels and considered the decisive factor underlying the greenhouse effect. Besides constituting a carbon storage, forests hold an additional CO 2 abatement potential which can be realised by continuous utilisation of wood. (orig./EF) [de

  16. Coal-based synthetic natural gas (SNG): A solution to China’s energy security and CO2 reduction?

    International Nuclear Information System (INIS)

    Ding, Yanjun; Han, Weijian; Chai, Qinhu; Yang, Shuhong; Shen, Wei

    2013-01-01

    Considering natural gas (NG) to be the most promising low-carbon option for the energy industry, large state owned companies in China have established numerous coal-based synthetic natural gas (SNG) projects. The objective of this paper is to use a system approach to evaluate coal-derived SNG in terms of life-cycle energy efficiency and CO 2 emissions. This project examined main applications of the SNG and developed a model that can be used for evaluating energy efficiency and CO 2 emissions of various fuel pathway systems. The model development started with the GREET model, and added the SNG module and an end-use equipment module. The database was constructed with Chinese data. The analyses show when the SNG are used for cooking, power generation, steam production for heating and industry, life-cycle energies are 20–108% higher than all competitive pathways, with a similar rate of increase in life-cycle CO 2 emissions. When a compressed natural gas (CNG) car uses the SNG, life-cycle CO 2 emission will increase by 150–190% compared to the baseline gasoline car and by 140–210% compared to an electric car powered by electricity from coal-fired power plants. The life-cycle CO 2 emission of SNG-powered city bus will be 220–270% higher than that of traditional diesel city bus. The gap between SNG-powered buses and new hybrid diesel buses will be even larger—life-cycle CO 2 emission of the former being around 4 times of that of the latter. It is concluded that the SNG will not accomplish the tasks of both energy conservation and CO 2 reduction. - Highlights: ► We evaluated life-cycle energy efficiency and CO 2 emissions of coal-derived SNG. ► We used GREET model and added a coal-based SNG and an end-use modules. ► The database was constructed with Chinese domestic data. ► Life-cycle energies and CO 2 emissions of coal-based SNG are 20–100% higher. ► Coal-based SNG is not a solution to both energy conservation and CO 2 reduction

  17. Possible pathways for dealing with Japan's post-Fukushima challenge and achieving CO2 emission reduction targets in 2030

    International Nuclear Information System (INIS)

    Su, Xuanming; Zhou, Weisheng; Sun, Faming; Nakagami, Ken'Ichi

    2014-01-01

    Considering the unclear nuclear future of Japan after Fukushima Dai-ichi nuclear power plant accident since Mar. 11, 2011, this study assesses a series of energy consumption scenarios including the reference scenario, nuclear limited scenarios and current nuclear use level scenario for Japan in 2030 by the G-CEEP (Glocal Century Energy Environment Planning) model. The simulation result for each scenario is firstly presented in terms of primary energy consumption, electricity generation, CO 2 emission, marginal abatement cost and GDP (gross domestic product) loss. According to the results, energy saving contributes the biggest share in total CO 2 emission reduction, regardless of different nuclear use levels and different CO 2 emission reduction levels. A certain amount of coal generation can be retained in the nuclear limited scenarios due to the applying of CCS (carbon capture and storage). The discussion indicates that Japan needs to improve energy use efficiency, increase renewable energy and introduce CCS in order to reduce the dependence on nuclear power and to achieve CO 2 emission reduction target in 2030. In addition, it is ambitious for Japan to achieve the zero nuclear scenario with 30% CO 2 emission reduction which will cause a marginal abatement cost of 383 USD/tC and up to −2.54% GDP loss from the reference scenario. Dealing with the nuclear power issue, Japan is faced with a challenge as well as an opportunity. - Highlights: • Nuclear use limited and carbon emission reduction scenarios for Japan in 2030. • Contributions of different abatement options to carbon emissions. • CCS for reducing dependence on nuclear power

  18. Photocatalytic reduction of CO2 into hydrocarbon solar fuels over g-C3N4-Pt nanocomposite photocatalysts.

    Science.gov (United States)

    Yu, Jiaguo; Wang, Ke; Xiao, Wei; Cheng, Bei

    2014-06-21

    Photocatalytic reduction of CO2 into renewable hydrocarbon fuels is an alternative way to develop reproducible energy, which is also a promising way to solve the problem of the greenhouse effect. In this work, graphitic carbon nitride (g-C3N4) was synthesized by directly heating thiourea at 550 °C and then a certain amount of Pt was deposited on it to form g-C3N4-Pt nanocomposites used as catalysts for photocatalytic reduction of CO2 under simulated solar irradiation. The main products of photocatalysis were CH4, CH3OH and HCHO. The deposited Pt acted as an effective cocatalyst, which not only influenced the selectivity of the product generation, but also affected the activity of the reaction. The yield of CH4 first increased upon increasing the amount of Pt deposited on the g-C3N4 from 0 to 1 wt%, then decreased at 2 wt% Pt loading. The production rates of CH3OH and HCHO also increased with the content of Pt increasing from 0 to 0.75 wt% and the maximum yield was observed at 0.75 wt%. The Pt nanoparticles (NPs) could facilitate the transfer and enrichment of photogenerated electrons from g-C3N4 to its surface for photocatalytic reduction of CO2. At the same time, Pt was also used a catalyst to promote the oxidation of products. The transient photocurrent response further confirmed the proposed photocatalytic reduction mechanism of CO2. This work indicates that the deposition of Pt is a good strategy to improve the photoactivity and selectivity of g-C3N4 for CO2 reduction.

  19. Potential evaluation of CO2 storage and enhanced oil recovery of tight oil reservoir in the Ordos Basin, China.

    Science.gov (United States)

    Tian, Xiaofeng; Cheng, Linsong; Cao, Renyi; Zhang, Miaoyi; Guo, Qiang; Wang, Yimin; Zhang, Jian; Cui, Yu

    2015-07-01

    Carbon -di-oxide (CO2) is regarded as the most important greenhouse gas to accelerate climate change and ocean acidification. The Chinese government is seeking methods to reduce anthropogenic CO2 gas emission. CO2 capture and geological storage is one of the main methods. In addition, injecting CO2 is also an effective method to replenish formation energy in developing tight oil reservoirs. However, exiting methods to estimate CO2 storage capacity are all based on the material balance theory. This was absolutely correct for normal reservoirs. However, as natural fractures widely exist in tight oil reservoirs and majority of them are vertical ones, tight oil reservoirs are not close. Therefore, material balance theory is not adaptive. In the present study, a new method to calculate CO2 storage capacity is presented. The CO2 effective storage capacity, in this new method, consisted of free CO2, CO2 dissolved in oil and CO2 dissolved in water. Case studies of tight oil reservoir from Ordos Basin was conducted and it was found that due to far lower viscosity of CO2 and larger solubility in oil, CO2 could flow in tight oil reservoirs more easily. As a result, injecting CO2 in tight oil reservoirs could obviously enhance sweep efficiency by 24.5% and oil recovery efficiency by 7.5%. CO2 effective storage capacity of Chang 7 tight oil reservoir in Longdong area was 1.88 x 10(7) t. The Chang 7 tight oil reservoir in Ordos Basin was estimated to be 6.38 x 10(11) t. As tight oil reservoirs were widely distributed in Songliao Basin, Sichuan Basin and so on, geological storage capacity of CO2 in China is potential.

  20. The contribution of energy efficiency and renewability to the reduction of CO2 emissions

    International Nuclear Information System (INIS)

    Paredes, J.A.; Mateo, I.

    1995-01-01

    The European Commission has proposed a series of measures, among which the imposition of a tax on the consumption of energy and CO 2 emissions. Different organizations, among them Eurelectric, have opposed this tax, arguing that there exist alternative solutions, such as the adoption of voluntary commitments between companies/national governments, to reduce CO 2 emissions and which at the same time have a much lower cost/benefit ratio: the effects of the increased use of natural gas in electricity generation, improvements in energy efficiency and the promotion and development of cogeneration and renewable energies on CO 2 emissions on a national level (Spain), as well as applications of the same principles within a particular company (Union Fenosa). 3 tabs

  1. H2-assisted CO2 thermochemical reduction on La0.9Ca0.1FeO3-δ membranes: a kinetics study

    KAUST Repository

    Wu, Xiao-Yu; Ghoniem, Ahmed F.

    2017-01-01

    Kinetics data for CO2 thermochemical reduction in an isothermal membrane reactor is required to identify the rate-limiting steps. Here, we report a detailed reaction kinetics study on this process supported by an La0.9Ca0.1FeO3-δ (LCF-91) membrane. The dependence of CO2 reduction rate on various operating conditions is examined such as CO2 concentration on the feed side, fuel concentrations on the sweep side and temperatures. CO2 reduction rate is proportional to the oxygen flux across the membrane, and the measured maximum fluxes are 0.191 and 0.164 μmol cm-2 s-1 with 9.5% H2 and 11.6% CO on the sweep side at 990oC, respectively. Fuel is used to maintain the chemical potential gradient across the membrane and CO is used by construction to derive the surface reaction kinetics. This membrane also exhibits stable performances for 106 hours. A resistance-network model is developed to describe the oxygen transport process and the kinetics data are parameterized using the experimental values. The model shows a transition of the rate limiting step between the surface reactions on the feed side and the sweep side depending on the operating conditions.

  2. H2-assisted CO2 thermochemical reduction on La0.9Ca0.1FeO3-δ membranes: a kinetics study

    KAUST Repository

    Wu, Xiao-Yu

    2017-11-04

    Kinetics data for CO2 thermochemical reduction in an isothermal membrane reactor is required to identify the rate-limiting steps. Here, we report a detailed reaction kinetics study on this process supported by an La0.9Ca0.1FeO3-δ (LCF-91) membrane. The dependence of CO2 reduction rate on various operating conditions is examined such as CO2 concentration on the feed side, fuel concentrations on the sweep side and temperatures. CO2 reduction rate is proportional to the oxygen flux across the membrane, and the measured maximum fluxes are 0.191 and 0.164 μmol cm-2 s-1 with 9.5% H2 and 11.6% CO on the sweep side at 990oC, respectively. Fuel is used to maintain the chemical potential gradient across the membrane and CO is used by construction to derive the surface reaction kinetics. This membrane also exhibits stable performances for 106 hours. A resistance-network model is developed to describe the oxygen transport process and the kinetics data are parameterized using the experimental values. The model shows a transition of the rate limiting step between the surface reactions on the feed side and the sweep side depending on the operating conditions.

  3. Ultrathin bismuth nanosheets from in situ topotactic transformation for selective electrocatalytic CO2 reduction to formate.

    Science.gov (United States)

    Han, Na; Wang, Yu; Yang, Hui; Deng, Jun; Wu, Jinghua; Li, Yafei; Li, Yanguang

    2018-04-03

    Electrocatalytic carbon dioxide reduction to formate is desirable but challenging. Current attention is mostly focused on tin-based materials, which, unfortunately, often suffer from limited Faradaic efficiency. The potential of bismuth in carbon dioxide reduction has been suggested but remained understudied. Here, we report that ultrathin bismuth nanosheets are prepared from the in situ topotactic transformation of bismuth oxyiodide nanosheets. They process single crystallinity and enlarged surface areas. Such an advantageous nanostructure affords the material with excellent electrocatalytic performance for carbon dioxide reduction to formate. High selectivity (~100%) and large current density are measured over a broad potential, as well as excellent durability for >10 h. Its selectivity for formate is also understood by density functional theory calculations. In addition, bismuth nanosheets were coupled with an iridium-based oxygen evolution electrocatalyst to achieve efficient full-cell electrolysis. When powered by two AA-size alkaline batteries, the full cell exhibits impressive Faradaic efficiency and electricity-to-formate conversion efficiency.

  4. Liberalised electricity markets, new bioenergy technologies, and GHG emission reductions: interactions and CO2 mitigation costs

    International Nuclear Information System (INIS)

    Gustavsson, L.; Madlener, R.

    1999-01-01

    We contrast recent developments in power and heat production with bioenergy, and natural-gas-fired condensing plants with and without decarbonisation, in the light of electricity market liberalisation. Our main focus is on CO 2 mitigation costs and carbon tax sensitivity of production costs. We find that CO 2 mitigation costs are lower for biomass systems using IGCC technology than for natural gas system using decarbonisation. However, based on current fuel prices natural-gas fired co-generation plants have the lowest production costs. Hence energy policy measures will be needed to promote biomass technologies and decarbonisation options on a liberalised market. (author)

  5. Climate Change and employment. Impact on employment in the European Union-25 of climate change and CO2 emission reduction measures by 2030

    Energy Technology Data Exchange (ETDEWEB)

    Dupressoir, S.; Belen Sanchez, A.; Bobe, P.; Hoefele, V. (and others)

    2007-05-15

    This study was intended provide an analysis of the potential costs and benefits for employment of the policies and measures against climate change as well as of the manifestations of the consequences of climate change in Europe. This report comprises two divisions. The first, entitled 'Impact of climate change', attempts to determine the potential impact on employment in Europe of the consequences of climate change (Part 1). The second, entitled 'Impact of CO2 emission reduction measures', analyses the potential implications for employment of climate-change prevention policies in the EU with time-horizons of 2012 and 2030 (Parts 2 to 4). The conclusions and recommendations of the study appear in four parts : Part 1 analyses the potential consequences for employment of climatic warming in Europe; Part 2 presents the objectives, the hypotheses and the methodology of the 'impact of CO2 emission reduction measures' division; Part 3 analyses the foreseeable effects of CO2 emission reduction measures on employment in Europe; Part 4 offers general (or sector-wide) recommendations for measures and policies to promote positive effects and prevent negative effects. The concluding part discusses the uncertainties and identifies the questions deserving further investigation.

  6. A Robust Pyridyl-NHC-Ligated Rhenium Photocatalyst for CO2 Reduction in the Presence of Water and Oxygen

    Directory of Open Access Journals (Sweden)

    Casey A. Carpenter

    2018-01-01

    Full Text Available Re(pyNHC-PhCF3(CO3Br is a highly active photocatalyst for CO2 reduction. The PhCF3 derivative was previously empirically shown to be a robust catalyst. Here, the role of the PhCF3 group is probed computationally and the robust nature of this catalyst is analyzed with regard to the presence of water and oxygen introduced in controlled amounts during the photocatalytic reduction of CO2 to CO with visible light. This complex was found to work well from 0–1% water concentration reproducibly; however, trace amounts of water were required for benchmark Re(bpy(CO3Cl to give reproducible reactivity. When ambient air is added to the reaction mixture, the NHC complex was found to retain substantial performance (~50% of optimized reactivity at up to 40% ambient atmosphere and 60% CO2 while the Re(bpy(CO3Cl complex was found to give a dramatically reduced CO2 reduction reactivity upon introduction of ambient atmosphere. Through the use of time-correlated single photon counting studies and prior electrochemical results, we reasoned that this enhanced catalyst resilience is due to a mechanistic difference between the NHC- and bpy-based catalysts. These results highlight an important feature of this NHC-ligated catalyst: substantially enhanced stability toward common reaction contaminates.

  7. Peaking China’s CO2 Emissions: Trends to 2030 and Mitigation Potential

    Directory of Open Access Journals (Sweden)

    Qiang Liu

    2017-02-01

    Full Text Available China has submitted its nationally determined contribution to peak its energy-related emissions around 2030. To understand how China might develop its economy while controlling CO2 emissions, this study surveys a number of recent modeling scenarios that project the country’s economic growth, energy mix, and associated emissions until 2050. Our analysis suggests that China’s CO2 emissions will continue to grow until 2040 or 2050 and will approximately double their 2010 level without additional policy intervention. The alternative scenario, however, suggests that peaking CO2 emissions around 2030 requires the emission growth rate to be reduced by 2% below the reference level. This step would result in a plateau in China’s emissions from 2020 to 2030. This paper also proposed a deep de-carbonization pathway for China that is consistent with China’s goal of peaking emissions by around 2030, which can best be achieved through a combination of improvements in energy and carbon intensities. Our analysis also indicated that the potential for energy intensity decline will be limited over time. Thus, the peaking will be largely dependent on the share of non-fossil fuel energy in primary energy consumption.

  8. CO2 prevention through solar energy: potential and costs shown for the example of Muenster

    International Nuclear Information System (INIS)

    Sachse, M.; Bach, W.

    1994-01-01

    The two most important components of any climate protection policy committed to lowering CO 2 emissions are a more efficient energy utilisation and the rapid deployment of renewables. It is possible to cut energy consumption in Germany by about half. This can considerably increase the relative contribution of renewables to the power supply. Efficiency and renewables thus attain paramount importance from the climatological viewpoint: the former for its safety, the latter for their inexhaustibility. The present article examines on the basis of plausible assumptions what contribution solar energy can make to CO 2 prevention. It makes a detailed survey of the potential of differently structured city areas for the installation of solar energy plants and extrapolates the results obtained to the entire city on the basis of solar radiation and structural data. The authors focus on solar water heating, linking-up of solar collectors to district heating systems, and photovoltaic electricity production. The costs of investment, procurement, energy substitution, and CO 2 prevention are calculated, respectively, for flat-plate and vacuum collectors and compared. (orig./HP) [de

  9. Potential impact of increased temperature and CO2 on particulate dimethylsulfoniopropionate in the Southeastern Bering Sea

    Directory of Open Access Journals (Sweden)

    Peter A. Lee

    2011-06-01

    Full Text Available The potential impact of elevated sea surface temperature (SST and pCO2 on algal community structure and particulate dimethylsulfoniopropionate (DMSPp concentrations in the southeastern Bering Sea was examined using a shipboard “Ecostat” continuous culture system. The ecostat system was used to mimic the conditions projected to exist in the world's oceans by the end of this century (i.e. elevated pCO2 (750 ppm and elevated SST (ambient + 4°C. Two experiments were conducted using natural phytoplankton assemblages from the high-nutrient low-chlorophyll (HNLC central basin and from the middle domain of the southeastern continental shelf. At the HNLC site, the relative abundances of haptophytes and pelagophytes were higher and the relative abundance of diatoms lower under “greenhouse” conditions (i.e. combined 750 ppm CO2 and elevated temperature than control conditions (380 ppm CO2 and ambient temperature. This shift in algal community structure was accompanied by increases in DMSPp (2–3 fold, DMSPp:Chl a (2–3 fold and DMSP:PON (2 fold. At the continental shelf site, the changes in the relative abundances of haptophytes, pelagophytes and diatoms under “greenhouse” conditions were similar to those observed at the HNLC site, with 2.5 fold increases in DMSPp, 50–100% increases in DMSPp:Chl a and 1.8 fold increases in DMSP:PON. At both locations, changes in community structure and the DMSPp parameters were largely driven by increasing temperature. The observed changes were also consistent with the phytoplankton-DMS-albedo climate feedback mechanism proposed in the Charlson-Lovelock-Andreae-Warren (CLAW hypothesis.

  10. Technology priorities for transport in Asia: assessment of economy-wide CO2 emissions reduction for Lebanon

    DEFF Research Database (Denmark)

    Dhar, Subash; Marpaung, Charles O. P.

    2015-01-01

    mitigations actions (NAMA) given their strong contribution for development and therefore a methodology based on in-put out-put decomposition analysis is proposed for analysing economy wide CO2 emissions reductions. The methodology has been applied for the transport sector of Lebanon where alternative fuels...... of technologies and availability of technology characteristics. Non-motorized transport, mass transit and technologies that improve vehicle energy efficiency emerged as the three most preferred technology choices for the countries. These technology choices can be appropriate candidates for nationally appropriate......,improvement to cars (private and taxis) and buses for public transport were prioritized by stakeholders. The economy-wide CO2 emission reduce by 2,269 thousand tons by 2020 if the prioritized technologies are implemented in Lebanon. Fuel mix effect and structural effect would reduce CO2 emission by 2,611 thousand...

  11. Accelerating CO2-Emission Reductions via Corporate Programmes; Analysis of an Existing Corporate Programme

    NARCIS (Netherlands)

    Manser, J.; Handgraaf, M.J.J.; Schubert, R.; Gsottbauer, E.; Cornielje, M.; Lede, E.

    2013-01-01

    This working paper analyzes and assesses the COYou2 Program of the company Swiss Re. This corporate program allows employees to claim subsidies for the realization of various activities reducing their energy consumption and CO2-emissions at home. Examples of such activities are the purchase of a

  12. Acoustic waves in transversely excited atmospheric CO2 laser discharges: effect on performance and reduction techniques

    CSIR Research Space (South Africa)

    von Bergmann, HM

    2008-08-01

    Full Text Available Results are presented on the influence of acoustic waves on the performance of high-repetition-rate TEA CO2 lasers. It is shown that acoustic waves generated inside the laser cavity lead to nonuniform discharges, resulting in a deterioration...

  13. Influence of Operational Parameters on the Photocatalytic Activity of Powdered TiO2 for the Reduction of CO2

    Directory of Open Access Journals (Sweden)

    Oman Zuas

    2014-07-01

    Full Text Available In this report, the results from a study on the influence of operational parameters on TiO2 photocatalytic activity for CO2 reduction under an ultraviolet-visible (UV-vis illumination are presented. The results indicated that the TiO2 was found to be active for CO2 reduction with CH3OH as the major products, while other minor products (CO, CH4, and C2H4 were also detected. In addition, the formation of such reduction products was obviously influenced by the operational parameters. Under this study, the optimum operational parameters for CO2 reduction at 298 °K were determined to be: NaOH concentration 0.2 M, TiO2 dosage 2 g/L, volume of the reaction media 75 mL, the pressure of system 800 kPa. It was also found that the increase in UV-vis illumination time have increased the yield of product formation. A possible reaction pathway for the formation of the reduction products is also discussed.

  14. Climate Change Mitigation Pathways for Southeast Asia: CO2 Emissions Reduction Policies for the Energy and Transport Sectors

    Directory of Open Access Journals (Sweden)

    Lew Fulton

    2017-07-01

    Full Text Available As of June 2017, 150 countries have ratified the Paris Climate Agreement. This agreement calls for, among other things, strong reductions in CO2 emissions by 2030 and beyond. This paper reviews the Nationally Determined Contribution (NDCs plans of six Association of Southeast Asian Nations (ASEAN countries and compares their current and projected future CO2 levels across sectors, and their stated targets in the context of their economic and demographic situations. This comparison reveals wide variations in the types of targets, with the “ambition” level changing as the perspective changes from total CO2 to CO2/capita and per unit gross domestic product (GDP. We also review national plans as stated in NDCs and find that while there are many types of policies listed, few are quantified and no attempts are made to score individual or groups of policies for their likelihood in achieving stated targets. We conclude that more analysis is needed to better understand the possible impacts of current policies and plans on CO2 emissions, and whether current plans are adequate to hit targets. Considerations on better aligning targets are also provided.

  15. Subsurface watering resulted in reduced soil N2O and CO2 emissions and their global warming potentials than surface watering

    Science.gov (United States)

    Wei, Qi; Xu, Junzeng; Yang, Shihong; Liao, Linxian; Jin, Guangqiu; Li, Yawei; Hameed, Fazli

    2018-01-01

    Water management is an important practice with significant effect on greenhouse gases (GHG) emission from soils. Nitrous oxide (N2O) and carbon dioxide (CO2) emissions and their global warming potentials (GWPs) from subsurface watering soil (SUW) were investigated, with surface watering (SW) as a control. Results indicated that the N2O and CO2 emissions from SUW soils were somewhat different to those from SW soil, with the peak N2O and CO2 fluxes from SUW soil reduced by 28.9% and 19.4%, and appeared 72 h and 168 h later compared with SW. The fluxes of N2O and CO2 from SUW soils were lower than those from SW soil in both pulse and post-pulse periods, and the reduction was significantly (p0.1) lower that from SW soil. Moreover, N2O and CO2 fluxes from both watering treatments increased exponentially with increase of soil water-filled pore space (WFPS) and temperature. Our results suggest that watering soil from subsurface could significantly reduce the integrative greenhouse effect caused by N2O and CO2 and is a promising strategy for soil greenhouse gases (GHGs) mitigation. And the pulse period, contributed most to the reduction in emissions of N2O and CO2 from soils between SW and SUW, should be a key period for mitigating GHGs emissions. Response of N2O and CO2 emissions to soil WFPS and temperature illustrated that moisture was the dominant parameters that triggering GHG pulse emissions (especially for N2O), and temperature had a greater effect on the soil microorganism activity than moisture in drier soil. Avoiding moisture and temperature are appropriate for GHG emission at the same time is essential for GHGs mitigation, because peak N2O and CO2 emission were observed only when moisture and temperature are both appropriate.

  16. Potential maternal effects of elevated atmospheric CO2 on development and disease severity in a Mediterranean legume

    Directory of Open Access Journals (Sweden)

    José M. Grünzweig

    2011-07-01

    Full Text Available Global change can greatly affect plant populations both directly by influencing growing conditions and indirectly by maternal effects on development of offspring. More information is needed on transgenerational effects of global change on plants and on their interactions with pathogens. The current study assessed potential maternal effects of atmospheric CO2 enrichment on performance and disease susceptibility of first-generation offspring of the Mediterranean legume Onobrychis crista-galli. Mother plants were grown at three CO2 concentrations, and the study focused on their offspring that were raised under common ambient climate and CO2. In addition, progeny were exposed to natural infection by the fungal pathogen powdery mildew. In one out of three years, offspring of high-CO2 treatments (440 and 600 ppm had lower shoot biomass and reproductive output than offspring of low-CO2 treatment (280 ppm. Disease severity in a heavy-infection year was higher in high-CO2 than in low-CO2 offspring. However, some of the findings on maternal effects changed when the population was divided into two functionally diverging plant types distinguishable by flower color (pink, Type P; white Type W. Disease severity in a heavy-infection year was higher in high-CO2 than in low-CO2 progeny in the more disease-resistant (Type P, but not in the more susceptible plant type (Type W. In a low-infection year, maternal CO2 treatments did not differ in disease severity. Mother plants of Type P exposed to low CO2 produced larger seeds than all other combinations of CO2 and plant type, which might contribute to higher offspring performance. This study showed that elevated CO2 potentially exerts environmental maternal effects on performance of progeny and, notably, also on their susceptibility to natural infection by a pathogen. Maternal effects of global change might differently affect functionally divergent plant types, which could impact population fitness and alter plant

  17. Soil CO2 Dynamics in a Tree Island Soil of the Pantanal: The Role of Soil Water Potential

    Science.gov (United States)

    Johnson, Mark S.; Couto, Eduardo Guimarães; Pinto Jr, Osvaldo B.; Milesi, Juliana; Santos Amorim, Ricardo S.; Messias, Indira A. M.; Biudes, Marcelo Sacardi

    2013-01-01

    The Pantanal is a biodiversity hotspot comprised of a mosaic of landforms that differ in vegetative assemblages and flooding dynamics. Tree islands provide refuge for terrestrial fauna during the flooding period and are particularly important to the regional ecosystem structure. Little soil CO2 research has been conducted in this region. We evaluated soil CO2 dynamics in relation to primary controlling environmental parameters (soil temperature and soil water). Soil respiration was computed using the gradient method using in situ infrared gas analyzers to directly measure CO2 concentration within the soil profile. Due to the cost of the sensors and associated equipment, this study was unreplicated. Rather, we focus on the temporal relationships between soil CO2 efflux and related environmental parameters. Soil CO2 efflux during the study averaged 3.53 µmol CO2 m−2 s−1, and was equivalent to an annual soil respiration of 1220 g C m−2 y−1. This efflux value, integrated over a year, is comparable to soil C stocks for 0–20 cm. Soil water potential was the measured parameter most strongly associated with soil CO2 concentrations, with high CO2 values observed only once soil water potential at the 10 cm depth approached zero. This relationship was exhibited across a spectrum of timescales and was found to be significant at a daily timescale across all seasons using conditional nonparametric spectral Granger causality analysis. Hydrology plays a significant role in controlling CO2 efflux from the tree island soil, with soil CO2 dynamics differing by wetting mechanism. During the wet-up period, direct precipitation infiltrates soil from above and results in pulses of CO2 efflux from soil. The annual flood arrives later, and saturates soil from below. While CO2 concentrations in soil grew very high under both wetting mechanisms, the change in soil CO2 efflux was only significant when soils were wet from above. PMID:23762259

  18. Highly efficient visible light photocatalytic reduction of CO2 to hydrocarbon fuels by Cu-nanoparticle decorated graphene oxide.

    Science.gov (United States)

    Shown, Indrajit; Hsu, Hsin-Cheng; Chang, Yu-Chung; Lin, Chang-Hui; Roy, Pradip Kumar; Ganguly, Abhijit; Wang, Chen-Hao; Chang, Jan-Kai; Wu, Chih-I; Chen, Li-Chyong; Chen, Kuei-Hsien

    2014-11-12

    The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.

  19. A CsPbBr3 Perovskite Quantum Dot/Graphene Oxide Composite for Photocatalytic CO2 Reduction.

    Science.gov (United States)

    Xu, Yang-Fan; Yang, Mu-Zi; Chen, Bai-Xue; Wang, Xu-Dong; Chen, Hong-Yan; Kuang, Dai-Bin; Su, Cheng-Yong

    2017-04-26

    Halide perovskite quantum dots (QDs), primarily regarded as optoelectronic materials for LED and photovoltaic devices, have not been applied for photochemical conversion (e.g., water splitting or CO 2 reduction) applications because of their insufficient stability in the presence of moisture or polar solvents. Herein, we report the use of CsPbBr 3 QDs as novel photocatalysts to convert CO 2 into solar fuels in nonaqueous media. Under AM 1.5G simulated illumination, the CsPbBr 3 QDs steadily generated and injected electrons into CO 2 , catalyzing CO 2 reduction at a rate of 23.7 μmol/g h with a selectivity over 99.3%. Additionally, through the construction of a CsPbBr 3 QD/graphene oxide (CsPbBr 3 QD/GO) composite, the rate of electron consumption increased 25.5% because of improved electron extraction and transport. This study is anticipated to provide new opportunities to utilize halide perovskite QD materials in photocatalytic applications.

  20. Viability and adaptation potential of indigenous microorganisms from natural gas field fluids in high pressure incubations with supercritical CO2.

    Science.gov (United States)

    Frerichs, Janin; Rakoczy, Jana; Ostertag-Henning, Christian; Krüger, Martin

    2014-01-21

    Carbon Capture and Storage (CCS) is currently under debate as large-scale solution to globally reduce emissions of the greenhouse gas CO2. Depleted gas or oil reservoirs and saline aquifers are considered as suitable reservoirs providing sufficient storage capacity. We investigated the influence of high CO2 concentrations on the indigenous bacterial population in the saline formation fluids of a natural gas field. Bacterial community changes were closely examined at elevated CO2 concentrations under near in situ pressures and temperatures. Conditions in the high pressure reactor systems simulated reservoir fluids i) close to the CO2 injection point, i.e. saturated with CO2, and ii) at the outer boundaries of the CO2 dissolution gradient. During the incubations with CO2, total cell numbers remained relatively stable, but no microbial sulfate reduction activity was detected. After CO2 release and subsequent transfer of the fluids, an actively sulfate-respiring community was re-established. The predominance of spore-forming Clostridiales provided evidence for the resilience of this taxon against the bactericidal effects of supercritical (sc)CO2. To ensure the long-term safety and injectivity, the viability of fermentative and sulfate-reducing bacteria has to be considered in the selection, design, and operation of CCS sites.

  1. Photocatalytic Reduction of CO2 to Methane on Pt/TiO2 Nanosheet Porous Film

    Directory of Open Access Journals (Sweden)

    Li Qiu-ye

    2014-01-01

    Full Text Available Anatase TiO2 nanosheet porous films were prepared by calcination of the orthorhombic titanic acid films at 400°C. They showed an excellent photocatalytic activity for CO2 photoreduction to methane, which should be related to their special porous structure and large Brunauer-Emmett-Teller (BET surface area. In order to further improve the photocatalytic activity, Pt nanoparticles were loaded uniformly with the average size of 3-4 nm on TiO2 porous films by the photoreduction method. It was found that the loading of Pt expanded the light absorption ability of the porous film and improved the transformation efficiency of CO2 to methane. The conversion yield of CO2 to methane on Pt/TiO2 film reached 20.51 ppm/h·cm2. The Pt/TiO2 nanosheet porous film was characterized by means of X-ray diffraction (XRD, scanning electron microscopy (SEM, transmission electron microscope (TEM, and ultraviolet-visible light diffuse reflectance spectra (UV-vis DRS. Moreover, the transient photocurrent-time curves showed that the Pt/TiO2 nanosheet porous film exhibited higher photocurrent, indicating that the higher separation efficiency of the photogenerated charge carriers was achieved.

  2. Soil application of an encapsulated CO2 source and its potential for management of western corn rootworm larvae.

    Science.gov (United States)

    Schumann, M; Patel, A; Vidal, S

    2014-02-01

    Western corn rootworm (Diabrotica virgifera virgifera LeConte) larvae use carbon dioxide (CO2) to locate the roots of their hosts. This study investigated whether an encapsulated CO2 source (CO2-emitting capsules) is able to outcompete CO2 gradients established by corn root respiration in the soil. Furthermore, the following two management options with the capsules were tested in semifield experiments (0.5- to 1-m2 greenhouse plots): the disruption of host location and an "attract-and-kill" strategy in which larvae were lured to a soil insecticide (Tefluthrin) between the corn rows. The attract-and-kill strategy was compared with an application of Tefluthrin in the corn rows (conventional treatment) at 33 and 18% of the standard field application rate. Application of the CO2-emitting capsules 30 cm from the plant base increased CO2 levels near the application point for up to 20 d with a peak at day 10. Both the disruption of host location and an attract-and-kill strategy caused a slight but nonsignificant reduction in larval densities. The disruption of host location caused a 17% reduction in larval densities, whereas an attract-and-kill strategy with Tefluthrin added at 33 and 18% of the standard application rate caused a 24 and 27% reduction in larval densities, respectively. As presently formulated, the CO2-emitting capsules, either with or without insecticide, do not provide adequate control of western corn rootworm.

  3. Marginal CO2 reduction cost in ENERGY 2000 development. A socio-economic evaluation of the marginal cost for the alternative reduction methods

    International Nuclear Information System (INIS)

    Maeng, H.

    1995-01-01

    The official Danish environmental plan involves a reduction of CO 2 within the next 30-50 years. This report describes the analysis of socio-economic cost/consequences of marginal CO 2 reduction by means of various technical solution models. Calculations by means of the special program subroutine SAMFOKO are based on energy balance in annual, monthly, daily and hourly scale. Heat and power savings as well as the development of decentralized power plants are considered in the supply model. Socio-economic consequences in form of charges and cost are discussed. (EG)

  4. Cadmium-Aluminum Layered Double Hydroxide Microspheres for Photocatalytic CO2Reduction

    KAUST Repository

    Saliba, Daniel

    2016-03-30

    We report the synthesis of cadmium-aluminum layered double hydroxide (CdAl LDH) using the reaction-diffusion framework. As the hydroxide anions diffuse into an agar gel matrix containing the mixture of aluminum and cadmium salts at a given ratio, they react to give the LDH. The LDH self-assembles inside the pores of the gel matrix into a unique spherical-porous shaped microstructure. The internal and external morphologies of the particles are studied by electron microscopy and tomography revealing interconnected channels and a high surface area. This material is shown to exhibit a promising performance in the photoreduction of carbon dioxide using solar light. Moreover, the palladium-decorated version shows a significant improvement in its reduction potential at room temperature. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Cadmium-Aluminum Layered Double Hydroxide Microspheres for Photocatalytic CO2Reduction

    KAUST Repository

    Saliba, Daniel; Ezzeddine, Alaa; Sougrat, Rachid; Khashab, Niveen M.; Hmadeh, Mohamad; Al-Ghoul, Mazen

    2016-01-01

    We report the synthesis of cadmium-aluminum layered double hydroxide (CdAl LDH) using the reaction-diffusion framework. As the hydroxide anions diffuse into an agar gel matrix containing the mixture of aluminum and cadmium salts at a given ratio, they react to give the LDH. The LDH self-assembles inside the pores of the gel matrix into a unique spherical-porous shaped microstructure. The internal and external morphologies of the particles are studied by electron microscopy and tomography revealing interconnected channels and a high surface area. This material is shown to exhibit a promising performance in the photoreduction of carbon dioxide using solar light. Moreover, the palladium-decorated version shows a significant improvement in its reduction potential at room temperature. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Cadmium-Aluminum Layered Double Hydroxide Microspheres for Photocatalytic CO2 Reduction.

    Science.gov (United States)

    Saliba, Daniel; Ezzeddine, Alaa; Sougrat, Rachid; Khashab, Niveen M; Hmadeh, Mohamad; Al-Ghoul, Mazen

    2016-04-21

    We report the synthesis of cadmium-aluminum layered double hydroxide (CdAl LDH) using the reaction-diffusion framework. As the hydroxide anions diffuse into an agar gel matrix containing the mixture of aluminum and cadmium salts at a given ratio, they react to give the LDH. The LDH self-assembles inside the pores of the gel matrix into a unique spherical-porous shaped microstructure. The internal and external morphologies of the particles are studied by electron microscopy and tomography revealing interconnected channels and a high surface area. This material is shown to exhibit a promising performance in the photoreduction of carbon dioxide using solar light. Moreover, the palladium-decorated version shows a significant improvement in its reduction potential at room temperature. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Elevated CO2 shifts the functional structure and metabolic potentials of soil microbial communities in a C4 agroecosystem.

    Science.gov (United States)

    Xiong, Jinbo; He, Zhili; Shi, Shengjing; Kent, Angela; Deng, Ye; Wu, Liyou; Van Nostrand, Joy D; Zhou, Jizhong

    2015-03-20

    Atmospheric CO2 concentration is continuously increasing, and previous studies have shown that elevated CO2 (eCO2) significantly impacts C3 plants and their soil microbial communities. However, little is known about effects of eCO2 on the compositional and functional structure, and metabolic potential of soil microbial communities under C4 plants. Here we showed that a C4 maize agroecosystem exposed to eCO2 for eight years shifted the functional and phylogenetic structure of soil microbial communities at both soil depths (0-5 cm and 5-15 cm) using EcoPlate and functional gene array (GeoChip 3.0) analyses. The abundances of key genes involved in carbon (C), nitrogen (N) and phosphorus (P) cycling were significantly stimulated under eCO2 at both soil depths, although some differences in carbon utilization patterns were observed between the two soil depths. Consistently, CO2 was found to be the dominant factor explaining 11.9% of the structural variation of functional genes, while depth and the interaction of depth and CO2 explained 5.2% and 3.8%, respectively. This study implies that eCO2 has profound effects on the functional structure and metabolic potential/activity of soil microbial communities associated with C4 plants, possibly leading to changes in ecosystem functioning and feedbacks to global change in C4 agroecosystems.

  8. Comparing Existing Pipeline Networks with the Potential Scale of Future U.S. CO2 Pipeline Networks

    Energy Technology Data Exchange (ETDEWEB)

    Dooley, James J.; Dahowski, Robert T.; Davidson, Casie L.

    2008-02-29

    There is growing interest regarding the potential size of a future U.S. dedicated CO2 pipeline infrastructure if carbon dioxide capture and storage (CCS) technologies are commercially deployed on a large scale. In trying to understand the potential scale of a future national CO2 pipeline network, comparisons are often made to the existing pipeline networks used to deliver natural gas and liquid hydrocarbons to markets within the U.S. This paper assesses the potential scale of the CO2 pipeline system needed under two hypothetical climate policies and compares this to the extant U.S. pipeline infrastructures used to deliver CO2 for enhanced oil recovery (EOR), and to move natural gas and liquid hydrocarbons from areas of production and importation to markets. The data presented here suggest that the need to increase the size of the existing dedicated CO2 pipeline system should not be seen as a significant obstacle for the commercial deployment of CCS technologies.

  9. Synthesis and photocatalytic CO2 reduction performance of Cu2O/Coal-based carbon nanoparticle composites

    Science.gov (United States)

    Dedong, Zhang; Maimaiti, Halidan; Awati, Abuduheiremu; Yisilamu, Gunisakezi; Fengchang, Sun; Ming, Wei

    2018-05-01

    The photocatalytic reduction of CO2 into hydrocarbons provides a promising approach to overcome the challenges of environmental crisis and energy shortage. Here we fabricated a cuprous oxide (Cu2O) based composite photocatalyst consisting of Cu2O/carbon nanoparticles (CNPs). To prepare the CNPs, coal samples from Wucaiwan, Xinjiang, China, were first treated with HNO3, followed by hydrogen peroxide (H2O2) oxidation to strip nanocrystalline carbon from coal. After linking with oxygen-containing group such as hydroxyl, coal-based CNPs with sp2 carbon structure and multilayer graphene lattice structure were synthesized. Subsequently, the CNPs were loaded onto the surface of Cu2O nanoparticles prepared by in-situ reduction of copper chloride (CuCl2·2H2O). The physical properties and chemical structure of the Cu2O/CNPs as well as photocatalytic activity of CO2/H2O reduction into CH3OH were measured. The results demonstrate that the Cu2O/CNPs are composed of spherical particles with diameter of 50 nm and mesoporous structure, which are suitable for CO2 adsorption. Under illumination of visible light, electron-hole pairs are generated in Cu2O. Thanks to the CNPs, the fast recombination of electron-hole pairs is suppressed. The energy gradient formed on the surface of Cu2O/CNPs facilitates the efficient separation of electron-hole pairs for CO2 reduction and H2O oxidation, leading to enhanced photocatalytic activity.

  10. Potential for CO2 sequestration and enhanced coalbed methane production in the Netherlands

    NARCIS (Netherlands)

    Hamelinck, C.N.; Schreurs, H.; Faaij, A.P.C.; Ruijg, G.J.; Jansen, Daan; Pagnier, H.; Bergen, F. van; Wolf, K.-H.; Barzandji, O.; Bruining, H.

    2006-01-01

    This study investigated the technical and economic feasibility of using CO2 for the enhanced production of coal bed methane (ECBM) in the Netherlands. This concept could lead to both CO2 storage by adsorbing CO2 in deep coal layers that are not suitable for mining, as well as production of methane.

  11. Identifying Different Types of Catalysts for CO2 Reduction by Ethane through Dry Reforming and Oxidative Dehydrogenation.

    Science.gov (United States)

    Porosoff, Marc D; Myint, Myat Noe Zin; Kattel, Shyam; Xie, Zhenhua; Gomez, Elaine; Liu, Ping; Chen, Jingguang G

    2015-12-14

    The recent shale gas boom combined with the requirement to reduce atmospheric CO2 have created an opportunity for using both raw materials (shale gas and CO2 ) in a single process. Shale gas is primarily made up of methane, but ethane comprises about 10 % and reserves are underutilized. Two routes have been investigated by combining ethane decomposition with CO2 reduction to produce products of higher value. The first reaction is ethane dry reforming which produces synthesis gas (CO+H2 ). The second route is oxidative dehydrogenation which produces ethylene using CO2 as a soft oxidant. The results of this study indicate that the Pt/CeO2 catalyst shows promise for the production of synthesis gas, while Mo2 C-based materials preserve the CC bond of ethane to produce ethylene. These findings are supported by density functional theory (DFT) calculations and X-ray absorption near-edge spectroscopy (XANES) characterization of the catalysts under in situ reaction conditions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Using global warming potential to compare methane and CO2 emissions

    International Nuclear Information System (INIS)

    Dufresne, J.L.

    2009-01-01

    Greenhouse gases affect the planetary heat budget. Any change of their concentration affects this budget and therefore the global mean surface temperature of the Earth. These gases have different radiative properties and different lifetimes in the atmosphere, which prevents any direct comparison of the consequences of their emissions on global warming. Almost twenty years ago, the Intergovernmental Panel on Climate Change (IPCC) proposed the global warming potential (GWP) as an index to compare the emissions of the various greenhouse gases. In a recent paper, it has been stated that the use of GWP leads to strongly underestimating the global warming due to constant methane emissions compared to that of constant CO 2 emissions. Here we show that it is not really the case. The GWP enables comparisons of global warming due to constant emissions for any prescribed period, 100 years being often used. But this comparison is not universal. For instance, the impact of methane is underestimated at the beginning of the chosen period while the impact of CO 2 is underestimated after this period

  13. Potential Mississippi oil recovery and economic impact from CO2 miscible flooding

    International Nuclear Information System (INIS)

    Moring, J.A.; Rogers, R.E.

    1991-01-01

    Maturing of Mississippi oil reservoirs has resulted in a steady decline in crude oil production in the state. This paper reports that, to evaluate the potential of enhanced recovery processes, particularly in the use of the state's large CO 2 reserves, for arresting this trend, the subject study was performed. A computer data base of over 1315 Mississippi reservoirs was established. All reservoirs were screened for applicability of the carbon dioxide miscible process. With models developed by the National Petroleum Council and DOE, incremental oil that could be produced from the carbon dioxide miscible process was calculated. Under selected economic conditions, carbon dioxide miscible flooding with utilization of carbon dioxide from the state's Norphlet formation (3-7 tcf reserves of high-purity CO 2 ) could produce 120 million barrels of incremental oil in Mississippi. Incremental state revenues as a consequence of this production were calculated to be $45 million of severance taxes, $50 million of corporate income taxes, and $60 million of royalty payments, expressed as present values

  14. Analysis of the Global Warming Potential of Biogenic CO2 Emission in Life Cycle Assessments.

    Science.gov (United States)

    Liu, Weiguo; Zhang, Zhonghui; Xie, Xinfeng; Yu, Zhen; von Gadow, Klaus; Xu, Junming; Zhao, Shanshan; Yang, Yuchun

    2017-01-03

    Biomass is generally believed to be carbon neutral. However, recent studies have challenged the carbon neutrality hypothesis by introducing metric indicators to assess the global warming potential of biogenic CO 2 (GWP bio ). In this study we calculated the GWP bio factors using a forest growth model and radiative forcing effects with a time horizon of 100 years and applied the factors to five life cycle assessment (LCA) case studies of bioproducts. The forest carbon change was also accounted for in the LCA studies. GWP bio factors ranged from 0.13-0.32, indicating that biomass could be an attractive energy resource when compared with fossil fuels. As expected, short rotation and fast-growing biomass plantations produced low GWP bio . Long-lived wood products also allowed more regrowth of biomass to be accounted as absorption of the CO 2 emission from biomass combustion. The LCA case studies showed that the total life cycle GHG emissions were closely related to GWP bio and energy conversion efficiency. By considering the GWP bio factors and the forest carbon change, the production of ethanol and bio-power appeared to have higher GHG emissions than petroleum-derived diesel at the highest GWP bio .

  15. Analysis of the Global Warming Potential of Biogenic CO2 Emission in Life Cycle Assessments

    Science.gov (United States)

    Liu, Weiguo; Zhang, Zhonghui; Xie, Xinfeng; Yu, Zhen; von Gadow, Klaus; Xu, Junming; Zhao, Shanshan; Yang, Yuchun

    2017-01-01

    Biomass is generally believed to be carbon neutral. However, recent studies have challenged the carbon neutrality hypothesis by introducing metric indicators to assess the global warming potential of biogenic CO2 (GWPbio). In this study we calculated the GWPbio factors using a forest growth model and radiative forcing effects with a time horizon of 100 years and applied the factors to five life cycle assessment (LCA) case studies of bioproducts. The forest carbon change was also accounted for in the LCA studies. GWPbio factors ranged from 0.13–0.32, indicating that biomass could be an attractive energy resource when compared with fossil fuels. As expected, short rotation and fast-growing biomass plantations produced low GWPbio. Long-lived wood products also allowed more regrowth of biomass to be accounted as absorption of the CO2 emission from biomass combustion. The LCA case studies showed that the total life cycle GHG emissions were closely related to GWPbio and energy conversion efficiency. By considering the GWPbio factors and the forest carbon change, the production of ethanol and bio-power appeared to have higher GHG emissions than petroleum-derived diesel at the highest GWPbio. PMID:28045111

  16. Real-time detection of root zone-CO2 and its potential for irrigation scheduling

    Directory of Open Access Journals (Sweden)

    Klaus Spohrer

    2015-08-01

    Full Text Available Als Basis für die Bewässerungsplanung wurde die Eignung von CO2-Messungen im Wurzelraum (WR-CO2 untersucht und evaluiert. Die grundlegende Annahme war, dass Pflanzen als Reaktion auf eine defizitäre Wasserversorgung die Wurzelatmung reduzieren. Die Untersuchungen an Apfelbäumen konnten zeigen, dass das WR-CO2 zu großen Teilen (56–72 % seinen Ursprung in der pflanzenspezifischen CO2-Produktion (v. a. Wurzelatmung hat. Darüber hinaus reagierte das WR-CO2 deutlich auf Bewässerung und korrelierte bei der Austrocknung mit dem Bodenwassergehalt. Da Veränderungen beim WR-CO2 sich auch in Veränderungen beim Pflanzenwasserstatus widerspiegelten, besitzt das WR-CO2 Potenzial zur Ermittlung des Bewässerungsbedarfs der untersuchten Apfelbäume. Die Übertragbarkeit auf weitere Nutzpflanzen wird untersucht.

  17. Condensing gas boilers for energy efficiency and reduction of CO2 and NOx

    International Nuclear Information System (INIS)

    Stewardson, E.

    1994-01-01

    The objectives of the study are: 1) to demonstrate the effectiveness of condensing gas boiler hot water system in reducing energy costs and pollution; 2) to illustrate the importance of marketing this technology to uninformed end users. The development of condensing boilers in the European Community, the materials used, product designs, key performance measures, and the types of applications suited to these products are outlined. Using calculations from a body of work produced by the Chartered Institute of Building Service Engineers in Britain, it is demonstrated how seasonal efficiency differs from combustion efficiency, and how the added capital cost for these boilers may be recovered within an acceptable commercial pay back period from fuel cost savings. Applying current NO x and CO 2 information from a body of the CE Technical Committees, the author show how these products can reduce pollution levels both from CO 2 and NO x . An example of marketing these products to a largely uninformed end user customer market is cited. 2 refs., 3 tabs., 12 figs. (orig.)

  18. Effects of wind intermittency on reduction of CO2 emissions: The case of the Spanish power system

    International Nuclear Information System (INIS)

    Gutiérrez-Martín, F.; Da Silva-Álvarez, R.A.; Montoro-Pintado, P.

    2013-01-01

    Renewable energy sources are believed to reduce drastically greenhouse gas emissions that would otherwise be generated from fossil fuels used to generate electricity. This implies that a unit of renewable energy will replace a unit of fossil-fuel, with its CO 2 emissions, on an equivalent basis – with no other effects on the grid. But, the fuel economy and emissions in the existing power systems are not proportional with the electricity production of intermittent sources due to cycling of the fossil-fuel plants that make up the balance of the grid (i.e. changing the power output makes thermal units to operate less efficiently). This study focuses in the interactions between wind generation and thermal plants cycling, by establishing the levels of extra fuel use caused by decreased efficiencies of fossil back-up for wind electricity in Spain. We analyze the production of all thermal plants in 2011, studying scenarios where wind penetration causes major deviations in programming and we define a procedure for quantifying CO 2 reductions using emission factors and efficiency curves from existing installations; the objective is to discuss the real contribution of renewable energy to the environmental targets: the results show that CO 2 reductions are still relevant at high wind penetration, whilst we also suggest alternatives to improve reliability of the power system. - Highlights: ► Comprehensive analysis of interactions of wind and fuel utilities in the power system. ► Fuel economy is not proportional with wind generation due to cycling of fossil plants. ► The results show that CO 2 reductions are still relevant even at high wind penetration. ► Alternatives to improve reliability of future power systems are also pointed out

  19. Investigation of the potential of coal combustion fly ash for mineral sequestration of CO2 by accelerated carbonation

    International Nuclear Information System (INIS)

    Ukwattage, N.L.; Ranjith, P.G.; Wang, S.H.

    2013-01-01

    Mineral carbonation of alkaline waste materials is being studied extensively for its potential as a way of reducing the increased level of CO 2 in the atmosphere. Carbonation converts CO 2 into minerals which are stable over geological time scales. This process occurs naturally but slowly, and needs to be accelerated to offset the present rate of emissions from power plants and other emission sources. The present study attempts to identify the potential of coal fly ash as a source for carbon storage (sequestration) through ex-situ accelerated mineral carbonation. In the study, two operational parameters that could affect the reaction process were tested to investigate their effect on mineralization. Coal fly ash was mixed with water to different water-to-solid ratios and samples were carbonated in a pressure vessel at different initial CO 2 pressures. Temperature was kept constant at 40 °C. According to the results, one ton of Hazelwood fly ash could sequester 7.66 kg of CO 2 . The pressure of CO 2 inside the vessel has an effect on the rate of CO 2 uptake and the water-to-solid ratio affects the weight gain after the carbonation of fly ash. The results confirm the possibility of the manipulation of process parameters in enhancing the carbonation reaction. - Highlights: ► Mineral sequestration CO 2 by of coal fly ash is a slow process under ambient conditions. ► It can be accelerated by manipulating the process parameters inside a reactor. ► Initial CO 2 pressure and water to solid mixing ratio inside the reactor are two of those operational parameters. ► According to the test results higher CO 2 initial pressure gives higher on rates of CO 2 sequestration. ► Water to fly ash mixing ratio effect on amount of CO 2 sequestered into fly ash

  20. A Co3O4-CDots-C3N4 three component electrocatalyst design concept for efficient and tunable CO2 reduction to syngas.

    Science.gov (United States)

    Guo, Sijie; Zhao, Siqi; Wu, Xiuqin; Li, Hao; Zhou, Yunjie; Zhu, Cheng; Yang, Nianjun; Jiang, Xin; Gao, Jin; Bai, Liang; Liu, Yang; Lifshitz, Yeshayahu; Lee, Shuit-Tong; Kang, Zhenhui

    2017-11-28

    Syngas, a CO and H 2 mixture mostly generated from non-renewable fossil fuels, is an essential feedstock for production of liquid fuels. Electrochemical reduction of CO 2 and H + /H 2 O is an alternative renewable route to produce syngas. Here we introduce the concept of coupling a hydrogen evolution reaction (HER) catalyst with a CDots/C 3 N 4 composite (a CO 2 reduction catalyst) to achieve a cheap, stable, selective and efficient route for tunable syngas production. Co 3 O 4 , MoS 2 , Au and Pt serve as the HER component. The Co 3 O 4 -CDots-C 3 N 4 electrocatalyst is found to be the most efficient among the combinations studied. The H 2 /CO ratio of the produced syngas is tunable from 0.07:1 to 4:1 by controlling the potential. This catalyst is highly stable for syngas generation (over 100 h) with no other products besides CO and H 2 . Insight into the mechanisms balancing between CO 2 reduction and H 2 evolution when applying the HER-CDots-C 3 N 4 catalyst concept is provided.

  1. Specific anion effects on copper surface through electrochemical treatment: Enhanced photoelectrochemical CO2 reduction activity of derived nanostructures induced by chaotropic anions

    Science.gov (United States)

    Navaee, Aso; Salimi, Abdollah

    2018-05-01

    Copper derivatives are the most prominent CO2 reduction electrocatalyst. Herein, the metallic copper has been electrochemically treated with some of common ionic salts such as N3bar, HPO2bar, S2bar, Fbar, Clbar, Brbar and Ibar based on the dissolution of a metallic working electrode in an aqueous solution to derive the surface roughness incorporated with nanostructures. Diverse surface morphology can be obtained when the ionic radii of anions are changed. Surface study reveals various roughness shapes based on the size and polarity of the anions, where the ions with higher ionic radii have higher impact on the Cu surface. In comparison, polyatomic oxyanion such as HPO2bar even with large ionic radii do not have enough strength to create the surface roughness than that of oxygen-free anions with large ionic radii. The photoelectrochemical behavior of the modified surfaces toward CO2 reduction is studied at a wide potential window in bicarbonate aqueous solution. Based on our investigations, treated surfaces by Ibar, Clbar and S2bargive a more surface roughness, while Ibar and N3bar offer higher catalytic activity toward CO2 reduction due to possible complexing ability of these anions with Cu cations, followed by formation of the co-catalyst semiconductor and facilitate electron transfer. This methodology can be applied to investigate the effect of ions on transition metals along with obtaining different surface morphologies tailored to different applications.

  2. CO2 Storage Potential of the Eocene Tay Sandstone, Central North Sea, UK

    Science.gov (United States)

    Gent, Christopher; Williams, John

    2017-04-01

    Carbon Capture and Storage (CCS) is crucial for low-carbon industry, climate mitigation and a sustainable energy future. The offshore capacity of the UK is substantial and has been estimated at 78 Gt of CO2 in saline aquifers and hydrocarbon fields. The early-mid Eocene Tay Sandstone Member of the Central North Sea (CNS) is a submarine-fan system and potential storage reservoir with a theoretical capacity of 123 Mt of CO2. The Tay Sandstone comprises of 4 sequences, amalgamating into a fan complex 125km long and 40 km at a minimum of 1500 m depth striking NW-SE, hosting several hydrocarbon fields including Gannett A, B, D and Pict. In order to better understand the storage potential and characteristics, the Tay Sandstone over Quadrant 21 has been interpreted using log correlation and 3D seismic. Understanding the internal and external geometry of the sandstone as well as the lateral extent of the unit is essential when considering CO2 vertical and horizontal fluid flow pathways and storage security. 3D seismic mapping of a clear mounded feature has revealed the youngest sequence of the Tay complex; a homogenous sand-rich channel 12 km long, 1.5 km wide and on average 100 m thick. The sandstone has porosity >35%, permeability >5 D and a net to gross of 0.8, giving a total pore volume of 927x106 m3. The remaining three sequences are a series of stacked channels and interbedded mudstones which are more quiescent on the seismic, however, well logs indicate each subsequent sequence reduce in net to gross with age as mud has a greater influence in the early fan system. Nevertheless, the sandstone properties remain relatively consistent and are far more laterally extensive than the youngest sequence. The Tay Sandstone spatially overlaps several other potential storage sites including the older Tertiary sandstones of the Cromarty, Forties and Mey Members and deeper Jurassic reservoirs. This favours the Tay Sandstone to be considered in a secondary or multiple stacked

  3. Mesoscale Assessment of CO2 Storage Potential and Geological Suitability for Target Area Selection in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Yujie Diao

    2017-01-01

    Full Text Available In China, south of the Yangtze River, there are a large number of carbon sources, while the Sichuan Basin is the largest sedimentary basin; it makes sense to select the targets for CO2 geological storage (CGUS early demonstration. For CO2 enhanced oil and gas, coal bed methane recovery (CO2-EOR, EGR, and ECBM, or storage in these depleted fields, the existing oil, gas fields, or coal seams could be the target areas in the mesoscale. This paper proposed a methodology of GIS superimposed multisource information assessment of geological suitability for CO2 enhanced water recovery (CO2-EWR or only storage in deep saline aquifers. The potential per unit area of deep saline aquifers CO2 storage in Central Sichuan is generally greater than 50 × 104 t/km2 at P50 probability level, with Xujiahe group being the main reservoir. CO2 storage potential of depleted gas fields is 53.73 × 108 t, while it is 33.85 × 108 t by using CO2-EGR technology. This paper recommended that early implementation of CGUS could be carried out in the deep saline aquifers and depleted gas fields in the Sichuan Basin, especially that of the latter because of excellent traps, rich geological data, and well-run infrastructures.

  4. Reduction of energy cost and CO2 emission for the furnace using energy recovered from waste tail-gas

    International Nuclear Information System (INIS)

    Jou, Chih-Ju G.; Wu, Chung-Rung; Lee, Chien-Li

    2010-01-01

    In this research, the waste tail gas emitted from petrochemical processes, e.g. catalytic reforming unit, catalytic cracking unit and residue desulfurization unit, was recovered and reused as a replacement of natural gas (NG). On-site experimental results show that both the flame length and orange-yellowish brightness decrease with more proportion of waste gas fuel added to the natural gas, and that the adiabatic temperature of the mixed fuel is greater than 1800 o C. A complete replacement of natural gas by the recovered waste gas fuel will save 5.8 x 10 6 m 3 of natural gas consumption, and 3.5 x 10 4 tons of CO 2 emission annually. In addition, the reduction of residual O 2 concentration in flue gases from 4% to 3% will save 1.1 x 10 6 m 3 of natural gas consumption, reduce 43.0% of NO x emission, and 1.3 x 10 3 tons of CO 2 emission annually. Thus, from the viewpoint of the overall economics and sustainable energy policy, recovering the waste tail gas energy as an independent fuel source to replace natural gas is of great importance for saving energy, reducing CO 2 emission reduction, and lowering environmental impact.

  5. Monitoring underground migration of sequestered CO2 using self-potential methods

    Science.gov (United States)

    Ishido, T.; Pritchett, J.; Tosha, T.; Nishi, Y.; Nakanishi, S.

    2013-12-01

    An appropriate monitoring program is indispensable for an individual geologic storage project to aid in answering various operational questions by detecting changes within the reservoir and to provide early warning of potential CO2 leakage through the caprock. Such a program is also essential to reduce uncertainties associated with reservoir parameters and to improve the predictive capability of reservoir models. Repeat geophysical measurements performed at the earth surface show particular promise for monitoring large subsurface volumes. To appraise the utility of geophysical techniques, Ishido et al. carried out numerical simulations of an aquifer system underlying a portion of Tokyo Bay and calculated the temporal changes in geophysical observables caused by changing underground conditions as computed by reservoir simulation (Energy Procedia, 2011). They used 'geophysical postprocessors' to calculate the resulting temporal changes in the earth-surface distributions of microgravity, self-potential (SP), apparent resistivity (from MT surveys) and seismic observables. The applicability of any particular method is likely to be highly site-specific, but these calculations indicate that none of these techniques should be ruled out altogether. Some survey techniques (gravity, MT resistivity) appear to be suitable for characterizing long-term changes, whereas others (seismic reflection, SP) are quite responsive to short term disturbances. The self-potential postprocessor calculates changes in subsurface electrical potential induced by pressure disturbances through electrokinetic coupling (Ishido & Pritchett, JGR 1999). In addition to electrokinetic coupling, SP anomalies may be generated by various other mechanisms such as thermoelectric coupling, electrochemical diffusion potential, etc. In particular, SP anomalies of negative polarity, which are frequently observed near wells, appear to be caused by an underground electrochemical mechanism similar to a galvanic cell

  6. CO-2 reduction in the Danish transportation sector. Working paper 4: Cargo transport - road pricing system

    International Nuclear Information System (INIS)

    1997-03-01

    In this paper other financial control measures than fuel prices are considered for the transportation sector. The main effect discussed is that of the road pricing system. From the point of view of the CO 2 emission there could be introduced a registration tax for trucks over 4 tons as the higher transport expenditure would tend to reduce road transport demand. EU infrastructure tax directive however recommends taxes for trucks exceeding 12 tons. Road pricing will grow within the categories of lighter trucks but it is only a minor fraction of the total truck expenditure, taking into account fuel tax, weight tax and registration tax. Insurance cost is not included in these consideration. (EG) Prepared for Trafikministeriet. 22 refs

  7. Simulation-Based Analysis of the Potential of Alternative Fuels towards Reducing CO2 Emissions from Aviation

    Directory of Open Access Journals (Sweden)

    Karsten Kieckhäfer

    2018-01-01

    Full Text Available The mid-term framework of global aviation is shaped by air travel demand growth rates of 2–5% p.a. and ambitious targets to reduce aviation-related CO2 emissions by up to 50% until 2050. Alternative jet fuels such as bio- or electrofuels can be considered as a potential means towards low-emission aviation. While these fuels offer significant emission reduction potential, their market success depends on manifold influencing factors like the maturity of the production technology or the development of the price of conventional jet fuel. To study the potential for adoption of alternative jet fuels in aviation and the extent to which alternative fuels can contribute to the reduction targets, we deploy a System Dynamics approach. The results indicate that the adoption of alternative fuels and therefore their potential towards low-emissions aviation is rather limited in most scenarios considered since current production processes do not allow for competitive prices compared to conventional jet fuel. This calls for the development of new production processes that allow for economic feasibility of converting biomass or hydrogen into drop-in fuels as well as political measures to promote the adoption of alternative fuels.

  8. Enhanced photocatalytic reduction of CO2 to methanol by ZnO nanoparticles deposited on ZnSe nanosheet

    Science.gov (United States)

    Zhang, Shuangfang; Yin, Xiaohong; Zheng, Yinan

    2018-02-01

    In this work ZnO/ZnSe composites were successfully synthesized via solvothermal method and characterized by a series of experiments for investigating into their compositions, morphologies, microstructures and the activities of photocatalytic reduction of CO2. The methanol rates of bare ZnO and ZnSe respectively were 763.9 μmol/gcat/h and 503.88 μmol/gcat/h. However, the sample of 3 wt% ZnO/ZnSe performed better photocatalytic activity up 1581.82 μmol/gcat/h compared to bare ZnO and ZnSe. In the as-prepared photocatalyst the nanosheet of ZnSe benefited the light harvest; suitable deposition of ZnO on the ZnSe nanosheet constructed a type II heterojunction for transferring the photo-generated electron to reduce CO2.

  9. Preliminary Safety and Risk HSE Assessment. Application to the Potential Locations of a CO2 Geological Storage Pilot

    International Nuclear Information System (INIS)

    Recreo, F.; Eguilior, S.; Ruiz, C.; Lomba, L.; Hurtado, A.

    2015-01-01

    The location of a site safe and able to sequester CO2 for long periods of time is essential to gain public acceptance. This requires a long-term safety assessment developed in a robust and reliable framework. Site selection is the first step and requires specific research. This paper describes the application of the Selection and Classification Method of Geological Formations (SCF) developed to assess the potential of geological formations to CO2 storage. This assessment is based in the analysis of risks to Health, Safety and Environment (HSE) derived from potential CO2 leakage. Comparisons of the results obtained from a number of potential sites can help to select the best candidate for CO2 injection. The potential impact will be related to three key potential features of CO2 geological storage: the potential of the target geological formation for long term CO2 containment; the potential for secondary containment on containment failure of the target formation; and the site's potential to mitigate and/or disperse CO2 leakage if the primary and secondary containments fail. The methodology assesses each of these three characteristics through an analysis and assessment of properties of certain attributes of them. Uncertainty will remain as an input and output value of the methodology due to the usual lack of data in most site selection processes. The global uncertainty reports on the trust on the knowledge of the site characteristics. Therefore, the methodology enables comparing sites taking into account both the HSE risk expectation and the estimation of the quality of knowledge concerning such risk. The objective is to contribute to the selection of potential sites for a CO2 injection pilot plant in the Iberian Peninsula from the perspective of Safety and Risk Analysis.

  10. CO2 emissions reduction using energy conservation measures: EPA Region IV's experience

    International Nuclear Information System (INIS)

    Berish, C.; Day, R.; Sibold, K.; Tiller, J.

    1994-01-01

    EPA Region 4 concluded in a recent comparative environmental risk evaluation that global climate change could substantially impact the Southeast. To address this risk, Region 4 developed an action plan to promote cost-effective pollution prevention and reduce greenhouse gas emissions, The regional plan contains programs that aye specific to Region 4 as well as geographic components of the national Climate Change Action Plan. Sources of carbon dioxide emissions were targeted for pollution prevention based on an energy model that allows the user to create energy efficiency scenarios in four sectors: residential, commercial, industrial, and transportation. Activities were selected using the modeled information on sector reduction potentials and resource and cost-effectiveness criteria. Given the high level of uncertainty associated with climate change projections, the programs developed are all cost effective, prevent pollution and/or result in sound adaptation policies. Currently, policy makers at national, regional, and local levels are deciding on what types of energy efficiency programs to implement. The region's action plan is composed of several programs and approaches. The authors have developed implemented, and/or participated in the following: energy scenario model. EARTHWALK (residential energy conservation); energy conservation in affordable homes (new residences); Cool Communities Program (strategic tree planting and light colored surfaces); EPA's Green Lights Program; WAVE (water conservation), the Plant Protection Center; QUEST TO SAVE THE EARTH (outreach tools); energy and water use planning for the 1996 Olympic Games, and planning for sea-level rise. Reviewing the practices of the above programs will be the focus of this paper

  11. The long-run effects of economic, demographic, and political indices on actual and potential CO2 emissions.

    Science.gov (United States)

    Adom, Philip Kofi; Kwakwa, Paul Adjei; Amankwaa, Afua

    2018-07-15

    This study examines the long-run drivers of potential and actual CO 2 emissions in Ghana, a sub-Saharan Africa country. The use of the former helps address the reverse causality problem and capture the true long-run effects. The Stock-Watson dynamic OLS is used with data from 1970 to 2014. The result shows that potential CO 2 emissions improve model efficiency. Income (except in "other sector") and financial development (except in manufacturing and construction sector) have compelling positive and negative effects on actual and potential CO 2 emissions, respectively. A higher price (oil and electricity) reduces actual and potential CO 2 emissions, but electricity price is more vital in residential, buildings and commercial and public services sector, while oil price is crucial in the transport sector. Democracy lowers actual and potential CO 2 emissions in the aggregate (insignificant) and transport sectors but raises it in the manufacturing and construction sector. The effect is, however, inconsistent for the remaining sectors. Urbanization raises aggregate actual and potential CO 2 emissions, but the effect is inconsistent for the transport sector. The findings have important implications for policy formulation. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Potential of municipal solid waste (MSW) as a source of energy in Sao Paulo: its impact on CO2 balance

    International Nuclear Information System (INIS)

    Leao, A.L.; Ing Hwie Tan

    1998-01-01

    Energy generation is needed in Sao Paulo and MSW represents a promising alternative, although it is more expensive than hydroelectric power. About 14 900 t/day of MSW is generated, of which 8433 t/day is domestic and commercial MSW. From this amount, 1800 t will be destined to generate 30 MW of power. The eco-balance of CO 2 has been considered for incineration and recycling. The recycling program of plastics, metals, paper and glass would represent a significant reduction in energy and CO 2 emission. The total CO 2 released is 3.34 x 10 5 t/yr without recycling, and is 1.25 x 10 5 t/yr with a recycling program. Most of the CO 2 comes from plastics and paper production. Economic aspects could probably favor incineration with energy production as the best option. (author)

  13. Potential hazards of CO2 leakage in storage systems : learning from natural systems

    International Nuclear Information System (INIS)

    Beaubien, S.E.; Lombardi, S.; Ciotoli, G.; Annunziatellis, A.; Hatziyannis, G.; Metaxas, A.; Pearce, J.M.

    2005-01-01

    The Natural Analogues for the Storage of CO2 in the Geological Environment (NASCENT) Project has examined several naturally occurring carbon dioxide (CO 2 ) deposits throughout Europe to better understand the possible long term geological effects of a man-made CO 2 storage reservoir. Natural geological accumulations of CO 2 also occur widely throughout the world, some of which leak CO 2 to the surface, while others are effectively sealed. It is important to understanding the characteristics of both types of deposits in order to select and design underground storage sites for CO 2 storage. Four naturally occurring CO 2 sites were reviewed in this paper with reference to issues related to risk assessment, such as migration pathways; the speed of migration and mass flux rates; changes in groundwater chemistry; and, the effects these emissions may have on local populations and ecosystems. One site was located in northern Greece, near the Florina CO 2 gas field. The other three sites were in central Italy, including a selected area of the Latera geothermal complex, where natural deep CO 2 migrates upwards along faults and is emitted to the atmosphere; the San Vittorino intermontane basin where CO 2 -charged groundwaters cause the dissolution of limestone to form large sinkholes; and, the Ciampino area southeast of Rome, where CO 2 from deep-seated volcanism migrates along faults in a residential area. Work performed on these sites included soil gas, CO 2 flux and aqueous geochemical surveys. A GIS based model was also developed for the Latera site to assesses the risk of deep gas migration to surface. It was emphasized that these 4 sites are extreme cases compared to a man-made CO 2 geological storage site. For example all sites have an essentially infinite supply of deep CO 2 as the result of the thermo-metamorphic reactions forming this gas, whereas a man-made storage site would have a finite volume of gas which would be limited in its mass transfer out of the

  14. CO2 emission reduction policies in the greek residential sector: a methodological framework for their economic evaluation

    International Nuclear Information System (INIS)

    Mirasgedis, S.; Georgopoulou, E.; Sarafidis, Y.; Balaras, C.; Gaglia, A.; Lalas, D.P.

    2004-01-01

    This paper outlines a methodological framework for the economic evaluation of CO 2 emissions abatement policies and measures in the residential sector, taking into consideration both economic and social costs/benefits. The approach includes two stages: first, the measures under consideration are evaluated on the basis of a cost effectiveness analysis, which takes into account only the related net financial costs, thus highlighting win-win actions (i.e. measures presenting an economic benefit for end users without the provision of any economic subsidies or other similar policies); and second, the measures are re-evaluated using an integrated cost benefit analysis (where both the private and external costs/benefits are taken into account). The economic performance of the measures examined incorporates the effects of a variety of parameters, such as the region's climate, size and age of buildings, etc., which significantly affect the resulting ranking. The implementation of this framework in the Greek residential sector identified and prioritized a significant emissions reduction potential, which could be achieved with win-win measures and/or interventions that present a net social benefit. Measures with negative economic cost but positive net social benefit for the majority of the buildings examined include: (i) regular inspection of central heating boilers, (ii) use of thermostats in central heating boilers, (iii) sealing of openings, (iv) installation of solar collectors for hot water etc. The monetization of environmental benefits is shown to provide a powerful tool for highlighting priority actions in the context of a climate change mitigation policy

  15. Simultaneous studies on solar energy storage by CO2 reduction to HCOOH with Brilliant Green dye removal photoelectrochemically

    Directory of Open Access Journals (Sweden)

    V.S.K. Yadav

    2016-12-01

    Full Text Available The simultaneous study on photoelectrochemical CO2 reduction with Brilliant Green (BG dye removal was studied in the present work. Experimental studies were done in aqueous solutions of sodium and potassium based electrolytes using a cathode [Zinc (Zn and Tin (Sn] and a common cobalt oxide (Co3O4 anode electrocatalyst. The influence of reaction with electrolyte concentration for the both catalysts was shown clearly with respect to time. The selected electrocatalysts were able to reduce CO2 to formic acid (HCOOH along with high BG dye removal. With Sn as cathode, the maximum BG dye removal was obtained to be KHCO3–[95.9% (10 min–0.2 M], NaHCO3–[98.6% (15 min–0.6 M]. Similarly for Zn, KHCO3–[99.8% (10 min–0.4 M], NaHCO3–[99.9% (20 min–0.8 M] were observed respectively. Finally, the results have proven that higher efficiencies for BG dye removal were obtained along with HCOOH formation, which might be a better alternate for water purification and to decrease the atmospheric CO2 concentrations.

  16. Enhanced photocatalytic CO2 reduction to CH4 over separated dual co-catalysts Au and RuO2

    Science.gov (United States)

    Dong, Chunyang; Hu, Songchang; Xing, Mingyang; Zhang, Jinlong

    2018-04-01

    A spatially separated, dual co-catalyst photocatalytic system was constructed by the stepwise introduction of RuO2 and Au nanoparticles (NPs) at the internal and external surfaces of a three dimensional, hierarchically ordered TiO2-SiO2 (HTSO) framework (the final photocatalyst was denoted as Au/HRTSO). Characterization by HR-TEM, EDS-mapping, XRD and XPS confirmed the existence and spatially separated locations of Au and RuO2. In CO2 photocatalytic reduction (CO2PR), Au/HRTSO (0.8%) shows the optimal performance in both the activity and selectivity towards CH4; the CH4 yield is almost twice that of the singular Au/HTSO or HRTSO (0.8%, weight percentage of RuO2) counterparts. Generally, Au NPs at the external surface act as electron trapping agents and RuO2 NPs at the inner surface act as hole collectors. This advanced spatial configuration could promote charge separation and transfer efficiency, leading to enhanced CO2PR performance in both the yield and selectivity toward CH4 under simulated solar light irradiation.

  17. Japan's long-term energy outlook to 2050: Estimation for the potential of massive CO2 mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Komiyama, Ryoichi

    2010-09-15

    This paper analyzes Japan's energy outlook and CO2 emissions to 2050. Scenario analysis reveals that Japan's CO2 emissions in 2050 could be potentially reduced by 58% from the emissions in 2005. For achieving this massive mitigation, it is required to reduce primary energy supply per GDP by 60% in 2050 from the 2005 level and to expand the share of non-fossil fuel in total supply to 50% by 2050. Concerning power generation mix, nuclear will account for 60%, renewable for 30% in 2050. For massive CO2 abatement, Japan should tackle technological and economic challenges for large-scale deployment of advanced technologies.

  18. Organometallic Pt precursor on graphite substrate: deposition from SC CO2, reduction and morphology transformation as revealed by SFM

    International Nuclear Information System (INIS)

    Elmanovich, Igor V.; Naumkin, Alexander V.; Gallyamov, Marat O.; Khokhlov, Alexei R.

    2012-01-01

    Organometallic Pt precursor was deposited on model highly oriented pyrolytic graphite substrate from solutions in supercritical carbon dioxide. Morphology transformations during reduction process including real-time observations were studied by scanning force microscopy (SFM). We confirmed that SC CO 2 is a promising mediator in deposition process even for rather hydrophobic supports. SFM data show that thermal decomposition of the PtMe 2 (COD) precursor with subsequent hydrogen post-treatment allows one to obtain rather pure and well-defined Pt nanoparticles with average height above a substrate level of 4.5 ± 0.6 nm.

  19. Reduction of electricity use in Swedish industry and its impact on national power supply and European CO2 emissions

    International Nuclear Information System (INIS)

    Henning, Dag; Trygg, Louise

    2008-01-01

    Decreased energy use is crucial for achieving sustainable energy solutions. This paper presents current and possible future electricity use in Swedish industry. Non-heavy lines of business (e.g. food, vehicles) that use one-third of the electricity in Swedish industry are analysed in detail. Most electricity is used in the support processes pumping and ventilation, and manufacturing by decomposition. Energy conservation can take place through e.g. more efficient light fittings and switching off ventilation during night and weekends. By energy-carrier switching, electricity used for heat production is replaced by e.g. fuel. Taking technically possible demand-side measures in the whole lines of business, according to energy audits in a set of factories, means a 35% demand reduction. A systems analysis of power production, trade, demand and conservation was made using the MODEST energy system optimisation model, which uses linear programming and considers the time-dependent impact on demand for days, weeks and seasons. Electricity that is replaced by district heating from a combined heat and power (CHP) plant has a dual impact on the electricity system through reduced demand and increased electricity generation. Reduced electricity consumption and enhanced cogeneration in Sweden enables increased electricity export, which displaces coal-fired condensing plants in the European electricity market and helps to reduce European CO 2 emissions. Within the European emission trading system, those electricity conservation measures should be taken that are more cost-efficient than other ways of reducing CO 2 emissions. The demand-side measures turn net electricity imports into net export and reduce annual operation costs and net CO 2 emissions due to covering Swedish electricity demand by 200 million euros and 6 Mtonne, respectively. With estimated electricity conservation in the whole of Swedish industry, net electricity exports would be larger and net CO 2 emissions would be

  20. Direct reduction process using fines and with reduced CO2 emission

    CSIR Research Space (South Africa)

    Morrison, A

    2004-08-01

    Full Text Available , of which there is an abundant supply in South Africa. The rotary hearth process is one and two such units are currently in operation in Japan: one at Nippon Steel and another at Kobe Steel.3 Direct reduction for ferroalloy production offers...

  1. Kinetic Study of Photocatalytic Reduction of CO2 over TiO2.

    Czech Academy of Sciences Publication Activity Database

    Kočí, K.; Obalová, L.; Šolcová, Olga

    2010-01-01

    Roč. 31, č. 3 (2010), s. 395-407 ISSN 0208-6425 R&D Projects: GA ČR GA104/09/0694 Institutional research plan: CEZ:AV0Z40720504 Keywords : titania * photocatalytic reduction * methane Subject RIV: CC - Organic Chemistry OBOR OECD: Organic chemistry Impact factor: 0.252, year: 2010

  2. Future production and utilisation of biomass in Sweden: potentials and CO2 mitigation

    International Nuclear Information System (INIS)

    Boerjesson, P.; Gustavsson, L.; Christersson, L.; Linder, S.

    1997-01-01

    Swedish biomass production potential could be increased significantly if new production methods, such as optimised fertilisation, were to be used. Optimised fertilisation on 25% of Swedish forest land and the use of stem wood could almost double the biomass potential from forestry compared with no fertilisation, as both logging residues and large quantities of excess stem wood not needed for industrial purposes could be used for energy purposes. Together with energy crops and straw from agriculture, the total Swedish biomass potential would be about 230 TWh/yr or half the current Swedish energy supply if the demand for stem wood for building and industrial purposes were the same as today. The new production methods are assumed not to cause any significant negative impact on the local environment. The cost of utilising stem wood produced with optimised fertilisation for energy purposes has not been analysed and needs further investigation. Besides replacing fossil fuels and, thus, reducing current Swedish CO 2 emissions by about 65%, this amount of biomass is enough to produce electricity equivalent to 20% of current power production. Biomass-based electricity is produced preferably through co-generation using district heating systems in densely populated regions, and pulp industries in forest regions. Alcohols for transportation and stand-alone power production are preferably produced in less densely populated regions with excess biomass. A high intensity in biomass production would reduce biomass transportation demands. There are uncertainties regarding the future demand for stem wood for building and industrial purposes, the amount of arable land available for energy crop production and future yields. These factors will influence Swedish biomass potential and earlier estimates of the potential vary from 15 to 125 TWh/yr. (author)

  3. 100-μsec pulsed CO2 laser resurfacing of lower eyelids: erythema and rhytides reduction

    Science.gov (United States)

    Bell, Thomas; Harris, David M.; Schachter, Daniel; Burkart, John

    1997-05-01

    Lower eyelid skin is very thin with a low density of adnexal structures. Attempts to remove rhytides and improve surface appearance with chemical peels and dermabrasion have been disappointing. Laser resurfacing offers a new modality that may improve the outcome. We evaluated a very short duration (100 microsecond(s) ec) pulsed carbon-dioxide laser (Tru-PulseTM) in terms of healing time (duration of erythema) and efficacy (wrinkle reduction). Female patients aged 35 - 75 received laser resurfacing in a variety of cosmetic zones but only data from lower lids are reported here. Dosimetry varied from total fluences of 5 to 20 J/cm2 (9 mm2 spot, 250 - 500 mJ pulse, 1 to 4 passes). Patients followed a strict regime of post-op wound care. Pre-treatment and follow-up photographs were taken in a studio with constant photographic parameters. Projected 35 mm slides were evaluated side-by-side for clinical improvement and presence of erythema. Within the first 4 days post-op all (100%) lower eyelids exhibited erythema and swelling, at 7 days: 71%, 12 days: 60%, 3 weeks: 25%, and one (1) month or longer 7%. In our sample the longest duration of post-op lower lid erythema lasted 5 weeks. Most patients experienced 70 -80% wrinkle reduction with a range of 0 - 100%. Regression analysis was used to evaluate the relationships between percent wrinkle reduction and the treatment, demographic, and evaluation variables. There was a significant trend for wrinkles to improve over the 3 to 9 month evaluation period. Older patients improved slightly more than younger patients. There was no relationship between total energy density and wrinkle reduction.

  4. The influence of biopreparations on the reduction of energy consumption and CO2 emissions in shallow and deep soil tillage.

    Science.gov (United States)

    Naujokienė, Vilma; Šarauskis, Egidijus; Lekavičienė, Kristina; Adamavičienė, Aida; Buragienė, Sidona; Kriaučiūnienė, Zita

    2018-06-01

    The application of innovation in agriculture technologies is very important for increasing the efficiency of agricultural production, ensuring the high productivity of plants, production quality, farm profitability, the positive balance of used energy, and the requirements of environmental protection. Therefore, it is a scientific problem that solid and soil surfaces covered with plant residue have a negative impact on the work, traction resistance, energy consumption, and environmental pollution of tillage machines. The objective of this work was to determine the dependence of the reduction of energy consumption and CO 2 gas emissions on different biopreparations. Experimental research was carried out in a control (SC1) and seven different biopreparations using scenarios (SC2-SC8) using bacterial and non-bacterial biopreparations in different consistencies (with essential and mineral oils, extracts of various grasses and sea algae, phosphorus, potassium, humic and gibberellic acids, copper, zinc, manganese, iron, and calcium), estimating discing and plowing as the energy consumption parameters of shallow and deep soil tillage machines, respectively. CO 2 emissions were determined by evaluating soil characteristics (such as hardness, total porosity and density). Meteorological conditions such average daily temperatures (2015-20.3 °C; 2016-16.90 °C) and precipitations (2015-6.9 mm; 2016-114.9 mm) during the month strongly influenced different results in 2015 and 2016. Substantial differences between the averages of energy consumption identified in approximately 62% of biological preparation combinations created usage scenarios. Experimental research established that crop field treatments with biological preparations at the beginning of vegetation could reduce the energy consumption of shallow tillage machines by up to approximately 23%, whereas the energy consumption of deep tillage could be reduced by up to approximately 19.2% compared with the control

  5. How light-harvesting semiconductors can alter the bias of reversible electrocatalysts in favor of H2 production and CO2 reduction.

    Science.gov (United States)

    Bachmeier, Andreas; Wang, Vincent C C; Woolerton, Thomas W; Bell, Sophie; Fontecilla-Camps, Juan C; Can, Mehmet; Ragsdale, Stephen W; Chaudhary, Yatendra S; Armstrong, Fraser A

    2013-10-09

    The most efficient catalysts for solar fuel production should operate close to reversible potentials, yet possess a bias for the fuel-forming direction. Protein film electrochemical studies of Ni-containing carbon monoxide dehydrogenase and [NiFeSe]-hydrogenase, each a reversible electrocatalyst, show that the electronic state of the electrode strongly biases the direction of electrocatalysis of CO2/CO and H(+)/H2 interconversions. Attached to graphite electrodes, these enzymes show high activities for both oxidation and reduction, but there is a marked shift in bias, in favor of CO2 or H(+) reduction, when the respective enzymes are attached instead to n-type semiconductor electrodes constructed from CdS and TiO2 nanoparticles. This catalytic rectification effect can arise for a reversible electrocatalyst attached to a semiconductor electrode if the electrode transforms between semiconductor- and metallic-like behavior across the same narrow potential range (<0.25 V) that the electrocatalytic current switches between oxidation and reduction.

  6. Economic modeling of directed technical change: the case of CO2 emission reduction

    NARCIS (Netherlands)

    Otto, V.M.

    2006-01-01

    The potential of technical change for cost-effective pollution abatement typically differs from technology to technology. It therefore is the aim of this thesis to study how policy instruments can direct technical change to those technologies with the greatest potential for cost-effective pollution

  7. Japan’s Long-term Energy Demand and Supply Scenario to 2050 – Estimation for the Potential of Massive CO2 Mitigation

    OpenAIRE

    Ryoichi Komiyama; Chris Marnay; Michael Stadler; Judy Lai; Sam Borgeson; Brian Coffey; Inês Lima Azevedo

    2009-01-01

    In this analysis, we projected Japans energy demand/supply and energy-related CO2 emissions to 2050. Our analysis of various scenarios indicated that Japans CO2 emissions in 2050 could be potentially reduced by 26-58% from the current level (FY 2005) (Figure 1). These results suggest that Japan could set a CO2 emission reduction target for 2050 at between 30% and 60%. In order to reduce CO2 emissions by 60% in 2050 from the present level, Japan will have to strongly promote energy conservatio...

  8. Consequences of Market-Based Measures CO2-emission Reduction Maritime Transport for the Netherlands; Gevolgen Market Based Measures CO2-emissiereductie zeevaart voor Nederland

    Energy Technology Data Exchange (ETDEWEB)

    Wortelboer-van Donselaar, P.; Kansen, M.; Moorman, S. [Kennisinstituut voor Mobiliteitsbeleid KiM, Den Haag (Netherlands); Faber, J.; Koopman, M.; Smit, M. [CE Delft, Delft (Netherlands)

    2013-11-15

    The introduction of Market Based Measures (MBMs) to reduce the CO2 emissions of international sea shipping will have relatively limited economic effects for the Netherlands. Moreover, these effects are largely in line with those in other countries. For the Netherlands, however, the manner in which MBMS are organised and enforced is likely to be particularly important, given the importance of ports to the Dutch economy, the country's relatively large bunker sector, and the fact that Dutch shipowners operate relatively small vessels and on a relatively small scale. MBMs include pricing measures in the form of tax or trade systems, as well as other market-related proposals. In this research study, the consequences are analysed of four international MBM proposals for the Netherlands [Dutch] Om de CO2-uitstoot van de internationale zeevaartsector terug te dringen worden momenteel zogeheten Market Based Measures (MBMs), zoals bijvoorbeeld het veilen van emissierechten of het invoeren van een heffing, overwogen. De invoering van de MBMs zal voor Nederland relatief beperkte economische effecten hebben. Deze effecten wijken bovendien niet bijzonder af van die voor andere landen. De wijze waarop de MBMs worden georganiseerd en gehandhaafd, is voor Nederland mogelijk wel van onderscheidend belang. Dit gezien het belang van de havens voor de Nederlandse economie, de relatief grote bunkersector, en de relatief kleine schepen en kleinschaligheid van de Nederlandse reders.

  9. Unlocking the Electrocatalytic Activity of Antimony for CO2 Reduction by Two-Dimensional Engineering of the Bulk Material.

    Science.gov (United States)

    Li, Fengwang; Xue, Mianqi; Li, Jiezhen; Ma, Xinlei; Chen, Lu; Zhang, Xueji; MacFarlane, Douglas R; Zhang, Jie

    2017-11-13

    Two-dimensional (2D) materials are known to be useful in catalysis. Engineering 3D bulk materials into the 2D form can enhance the exposure of the active edge sites, which are believed to be the origin of the high catalytic activity. Reported herein is the production of 2D "few-layer" antimony (Sb) nanosheets by cathodic exfoliation. Application of this 2D engineering method turns Sb, an inactive material for CO 2 reduction in its bulk form, into an active 2D electrocatalyst for reduction of CO 2 to formate with high efficiency. The high activity is attributed to the exposure of a large number of catalytically active edge sites. Moreover, this cathodic exfoliation process can be coupled with the anodic exfoliation of graphite in a single-compartment cell for in situ production of a few-layer Sb nanosheets and graphene composite. The observed increased activity of this composite is attributed to the strong electronic interaction between graphene and Sb. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Metal-Organic-Framework-Mediated Nitrogen-Doped Carbon for CO2 Electrochemical Reduction

    KAUST Repository

    Wang, Riming; Sun, Xiaohui; Ould-Chikh, Samy; Osadchii, Dmitrii; Bai, Fan; Kapteijn, Freek; Gascon, Jorge

    2018-01-01

    A nitrogen-doped carbon was synthesized through the pyrolysis of the well-known metal-organic framework ZIF-8, followed by a subsequent acid treatment, and has been applied as a catalyst in the electrochemical reduction of carbon dioxide. The resulting electrode shows Faradaic efficiencies to carbon monoxide as high as ∼78%, with hydrogen being the only byproduct. The pyrolysis temperature determines the amount and the accessibility of N species in the carbon electrode, in which pyridinic-N and quaternary-N species play key roles in the selective formation of carbon monoxide.

  11. Metal-Organic-Framework-Mediated Nitrogen-Doped Carbon for CO2 Electrochemical Reduction

    KAUST Repository

    Wang, Riming

    2018-04-11

    A nitrogen-doped carbon was synthesized through the pyrolysis of the well-known metal-organic framework ZIF-8, followed by a subsequent acid treatment, and has been applied as a catalyst in the electrochemical reduction of carbon dioxide. The resulting electrode shows Faradaic efficiencies to carbon monoxide as high as ∼78%, with hydrogen being the only byproduct. The pyrolysis temperature determines the amount and the accessibility of N species in the carbon electrode, in which pyridinic-N and quaternary-N species play key roles in the selective formation of carbon monoxide.

  12. Wavelength Effect on Photocatalytic Reduction of CO(2) by Ag/TiO(2) Catalyst

    Czech Academy of Sciences Publication Activity Database

    Kočí, K.; Zatloukalová, K.; Obalová, L.; Krejčíková, Simona; Lacný, Z.; Čapek, L.; Hospodková, Alice; Šolcová, Olga

    2011-01-01

    Roč. 32, 5/SI/ (2011), s. 812-815 ISSN 0253-9837. [6th International Conference on Environmental Catalysis (6th ICEC). Beijing, 12.09.2010-15.09.2010] R&D Projects: GA ČR GA104/09/0694 Institutional research plan: CEZ:AV0Z40720504; CEZ:AV0Z10100521 Keywords : silver doping * titania * carbon dioxide reduction * photocatalysis * wavelength Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.171, year: 2011

  13. Multidecadal Increase in North Atlantic Coccolithophores and Potential Role of Increasing CO2

    Science.gov (United States)

    Rivero-Calle, S.; Gnanadesikan, A.; del Castillo, C. E.; Balch, W. M.; Guikema, S.

    2016-02-01

    As anthropogenic CO2 emissions acidify the oceans, calcifiers are expected to be negatively impacted. Using data from the Continuous Plankton Recorder, we show that coccolithophore occurrence in the North Atlantic has increased from 2 to over 20% from 1965 through 2010. We used Random Forest models to examine more than 20 possible environmental drivers of this change. CO2 and the Atlantic Multidecadal Oscillation were the best predictors. Since coccolithophore photosynthesis is strongly carbon-limited, we hypothesize that higher CO2 levels might be encouraging growth. A compilation of 41 independent laboratory studies supports our hypothesis. Our study shows a long-term basin-scale increase in coccolithophores and suggests that increasing pCO2 and temperature accelerated the growth rate of a key phytoplankton group for carbon cycling.

  14. Multidecadal increase in North Atlantic coccolithophores and the potential role of rising CO2

    Science.gov (United States)

    Rivero-Calle, Sara; Gnanadesikan, Anand; Del Castillo, Carlos E.; Balch, William M.; Guikema, Seth D.

    2015-12-01

    As anthropogenic carbon dioxide (CO2) emissions acidify the oceans, calcifiers generally are expected to be negatively affected. However, using data from the Continuous Plankton Recorder, we show that coccolithophore occurrence in the North Atlantic increased from ~2 to more than 20% from 1965 through 2010. We used random forest models to examine more than 20 possible environmental drivers of this change, finding that CO2 and the Atlantic Multidecadal Oscillation were the best predictors, leading us to hypothesize that higher CO2 levels might be encouraging growth. A compilation of 41 independent laboratory studies supports our hypothesis. Our study shows a long-term basin-scale increase in coccolithophores and suggests that increasing CO2 and temperature have accelerated the growth of a phytoplankton group that is important for carbon cycling.

  15. The potential for short-rotation woody crops to reduce US CO2 emissions

    International Nuclear Information System (INIS)

    Graham, R.L.; Wright, L.L.; Turhollow, A.F.

    1992-01-01

    Short-rotation woody crops (SRWC) could potentially displace fossil fuels and thus mitigate CO 2 buildup in the atmosphere. To determine how much fossil fuel SRWC might displace in the United States and what the associated fossil carbon savings might be, a series of assumptions must be made. These assumptions concern the net SRWC biomass yields per hectare (after losses); the amount of suitable land dedicated to SRWC production; wood conversion efficiencies to electricity or liquid fuels; the energy substitution properties of various fuels; and the amount of fossil fuel used in growing, harvesting, transporting, and converting SRWC biomass. Assuming the current climate, present production, and conversion technologies and considering a conservative estimate of the US land base available for SRWC (14 x 10 6 ha), it is calculated that SRWC energy could displace 33.2 to 73.1 x 10 6 Mg of fossil carbon releases, 3-6% of the current annual US emissions. The carbon mitigation potential per unit of land is larger with the substitution of SRWC for coal-based electricity production than for the substitution of SRWC-derived ethanol for gasoline. Assuming current climate, predicted conversion technology advancements, an optimistic estimate of the US land base available for SRWC (28 x 10 6 ha), and an optimistic average estimate of net SRWC yields (22.4 dry Mg/ha), it is calculate that SRWC energy could displace 148 to 242 x 10 6 Mg of annual fossil fuel carbon releases. Under this scenario, the carbon migration potential of SRWC-based electricity production would be equivalent to about 4.4% of current global fossil fuel emissions and 20% of current US fossil fuel emissions. 21 refs., 5 tabs

  16. Biomass for electricity in the EU-27: Potential demand, CO2 abatements and breakeven prices for co-firing

    International Nuclear Information System (INIS)

    Bertrand, Vincent; Dequiedt, Benjamin; Le Cadre, Elodie

    2014-01-01

    This paper analyses the potential of biomass-based electricity in the EU-27 countries, and interactions with climate policy and the EU ETS. We estimate the potential biomass demand from the existing power plants, and we match our estimates with the potential biomass supply in Europe. Furthermore, we compute the CO2 abatement associated with the co-firing opportunities in European coal plants. We find that the biomass demand from the power sector may be very high compared with potential supply. We also identify that co-firing can produce high volumes of CO 2 abatements, which may be two times larger than that of the coal-to-gas fuel switching. We also compute biomass and CO2 breakeven prices for co-firing. Results indicate that biomass-based electricity remains profitable with high biomass prices, when the carbon price is high: a Euros 16–24 (25–35, respectively) biomass price (per MWh prim ) for a Euros 20 (50, respectively) carbon price. Hence, the carbon price appears as an important driver, which can make profitable a high share of the potential biomass demand from the power sector, even with high biomass prices. This aims to gain insights on how biomass market may be impacted by the EU ETS and others climate policies. - Highlights: • Technical potential of biomass (demand and CO 2 abatement) in European electricity. • Calculation for co-firing and biomass power plants; comparison with potential biomass supply in EU-27 countries. • Calculation of biomass and CO 2 breakeven prices for co-firing. • Potential demand is 8–148% of potential supply (up to 80% of demand from co-firing). • High potential abatement from co-firing (up to 365 Mt/yr); Profitable co-firing with €16-24 (25–35) biomass price for €20 (50) CO 2 price

  17. CO2 production in animals: analysis of potential errors in the doubly labeled water method

    International Nuclear Information System (INIS)

    Nagy, K.A.

    1979-03-01

    Laboratory validation studies indicate that doubly labeled water ( 3 HH 18 O and 2 HH 18 O) measurements of CO 2 production are accurate to within +-9% in nine species of mammals and reptiles, a bird, and an insect. However, in field studies, errors can be much larger under certain circumstances. Isotopic fraction of labeled water can cause large errors in animals whose evaporative water loss comprises a major proportion of total water efflux. Input of CO 2 across lungs and skin caused errors exceeding +80% in kangaroo rats exposed to air containing 3.4% unlabeled CO 2 . Analytical errors of +-1% in isotope concentrations can cause calculated rates of CO 2 production to contain errors exceeding +-70% in some circumstances. These occur: 1) when little decline in isotope concentractions has occured during the measurement period; 2) when final isotope concentrations closely approach background levels; and 3) when the rate of water flux in an animal is high relative to its rate of CO 2 production. The following sources of error are probably negligible in most situations: 1) use of an inappropriate equation for calculating CO 2 production, 2) variations in rates of water or CO 2 flux through time, 3) use of H 2 O-18 dilution space as a measure of body water volume, 4) exchange of 0-18 between water and nonaqueous compounds in animals (including excrement), 5) incomplete mixing of isotopes in the animal, and 6) input of unlabeled water via lungs and skin. Errors in field measurements of CO 2 production can be reduced to acceptable levels (< 10%) by appropriate selection of study subjects and recapture intervals

  18. The potential role of nuclear energy in mitigating CO2 emissions in the United Arab Emirates

    International Nuclear Information System (INIS)

    AlFarra, Hasan Jamil; Abu-Hijleh, Bassam

    2012-01-01

    The annual CO 2 emissions have more than doubled in the UAE since 1990. Electricity generated by fossil fuels is responsible for almost half of the country's emissions. Keeping with the Kyoto Protocol, the UAE decided to integrate nuclear energy into the electricity scheme to mitigate CO 2 emissions as declared by the government. This paper evaluates the effectiveness of the UAE's proposed nuclear energy strategy in mitigating CO 2 emissions from the built environment up to year 2050. The IAEA's simulation model “MESSAGE” is used to estimate the energy demand and CO 2 emissions in the UAE up to year 2050. Several energy supply/fuels scenarios are modeled and simulated including the following: Business as Usual (BaU), the UAE proposed nuclear strategy (APR1400) as well as 12 more aggressive Clean Energy Era (CEE) proposed scenarios. Nuclear energy, especially in its extreme CEE scenario (8NPPs), was found to be more practical option in mitigating CO 2 than renewable energy and carbon capture and sequestration among the simulated scenarios. Nuclear energy also demonstrated an economic viability. The cost of electricity produced from nuclear energy was calculated to be 3.2 cents/kWh, significantly less than the current cost of 8.15 cents/kWh for electricity generation from fossil fuels in the UAE. - Highlights: ► Effectiveness of the UAE's proposed nuclear energy strategy in mitigating CO 2 emissions. ► Simulation is used to estimate the energy demand and CO 2 emissions in the UAE. ► Tested several energy supply/fuels scenarios on mitigating CO 2 .

  19. Production of H2 from aluminium/water reaction and its potential for CO2 methanation

    Science.gov (United States)

    Khai Phung, Khor; Sethupathi, Sumathi; Siang Piao, Chai

    2018-04-01

    Carbon dioxide (CO2) is a natural gas that presents in excess in the atmosphere. Owing to its ability to cause global warming, capturing and conversion of CO2 have attracted much attention worldwide. CO2 methanation using hydrogen (H2) is believed to be a promising route for CO2 removal. In the present work, H2 is produced using aluminum-water reaction and tested for its ability to convert CO2 to methane (CH4). Different type of water i.e. tap water, distilled water, deionized water and ultrapure water, concentration of sodium hydroxide (NaOH) (0.2 M to 1.0 M) and particle size of aluminum (45 m to 500 μm) were varied as parameter study. It was found that the highest yield of H2 was obtained using distilled water, 1.0 M of NaOH and 45μm particle size of aluminium. However, the highest yield of methane was achieved using a moderate and progressive H2 production (distilled water, 0.6 M of NaOH and 45 μm particle size of aluminium) which allowed sufficient time for H2 to react with CO2. It was concluded that 1130 ml of H2 can produce about 560 ppm of CH4 within 25 min of batch reaction using nickel catalyst.

  20. Research on CO2 Emission Reduction Mechanism of China’s Iron and Steel Industry under Various Emission Reduction Policies

    Directory of Open Access Journals (Sweden)

    Ye Duan

    2017-12-01

    Full Text Available In this paper, a two-stage dynamic game model of China’s iron and steel industry is constructed. Carbon tax levy, product subsidy, carbon capture and sequestration (CCS and other factors are included in the emission reduction mechanism. The effects of emissions reduction and the economic impact of China’s overall steel industry (and that of its six main regions are investigated for the first time under different scenarios. As new findings, we report the following: (1 Not all factors declined. The overall social welfare, consumer surplus, output and emissions decrease with a gradual increase in the reduction target, whereas the carbon tax value, unit value of product subsidies and total subsidies show a rising trend; (2 A combination of multiple emissions reduction policies is more effective than a single policy. With the implementation of a combined policy, regional output polarization has eased; (3 Steel output does not exceed 950 million tons, far below the current peak. These results will help the industry to formulate reasonable emissions reduction and output targets. In short, in effort to eliminate industry poverty and to alleviate overcapacity, the industry should not only adopt the various coordinated reduction policies, but also fully consider regional differences and reduction needs.

  1. Potential of CO2 lasers (10.6 µm associated with fluorides in inhibiting human enamel erosion

    Directory of Open Access Journals (Sweden)

    Thayanne Monteiro RAMOS-OLIVEIRA

    2014-01-01

    Full Text Available This in vitro study aimed to investigate the potential of CO2 lasers associated with different fluoride agents in inhibiting enamel erosion. Human enamel samples were randomly divided into 9 groups (n = 12: G1-eroded enamel; G2-APF gel; G3-AmF/NaF gel; G4-AmF/SnF2 solution; G5-CO2 laser (λ = 10.6 µm+APF gel; G6-CO2 laser+AmF/NaF gel; G7-CO2laser+AmF/SnF2solution; G8-CO2 laser; and G9-sound enamel. The CO2 laser parameters were: 0.45 J/cm2; 6 μs; and 128 Hz. After surface treatment, the samples (except from G9 were immersed in 1% citric acid (pH 4.0, 3 min. Surface microhardness was measured at baseline and after surface softening. The data were statistically analyzed by one-way ANOVA and Tukey’s tests (p < 0.05. G2 (407.6 ± 37.3 presented the highest mean SMH after softening, followed by G3 (407.5 ± 29.8 and G5 (399.7 ± 32.9. Within the fluoride-treated groups, G4 (309.0 ± 24.4 had a significantly lower mean SMH than G3 and G2, which were statistically similar to each other. AmF/NaF and APF application showed potential to protect and control erosion progression in dental enamel, and CO2 laser irradiation at 0.45J/cm2 did not influence its efficacy. CO2 laser irradiation alone under the same conditions could also significantly decrease enamel erosive mineral loss, although at lower levels.

  2. Dominant superiority of nuclear power in the reduction of CO2 emissions. Part 2

    International Nuclear Information System (INIS)

    Kase, Susumu

    2011-01-01

    Soon after the oil crisis in 1973, then French president Giscard d'Estaing and his administration very strongly persuaded the French people to make the nation's electrical power consist mainly of nuclear power. As a result, by the beginning of 1990's, as high as 80% of electric power generated in France became nuclear (30% in Japan). Add the share 9% of hydroelectric power, 89% of electric power generated in France is now free of fossil fuel, and emission of green house gases per capita in France is now 42% less than in Japan. What Japan should do first of all in the coming future is to emulate the French experience. That should result in a 35% reduction in green house gas emission by 2030 at an acceptable cost. To put that in practice we first must overcome the now considerably weakened but still stubbornly remaining national sentiment against nuclear power. It will take a very strong top to bottom persuasion by the leading sector of the society. As to this matter the author stressed in a separate paper that mankind, like in the instinctive language capability, possesses a born instinctive way of life to believe in and live by the dominant spirit of the time. And unfortunately the current spirit of the time still is tainted with irrational dislike of nuclear power which can be weakened by strong and persistent persuasion. (author)

  3. Analyzing the driving forces behind CO2 emissions and reduction strategies for energy-intensive sectors in Taiwan, 1996–2006

    International Nuclear Information System (INIS)

    Huang, Yun-Hsun; Wu, Jung-Hua

    2013-01-01

    Between 1996 and 2006, CO 2 emissions in Taiwan increased by approximately 60%, with the industrial sector accounting for 50% of that increase. Among all industrial sectors, iron and steel, petrochemicals, electronics, textiles, pulp and paper and cement accounted for approximately three-quarters of the total industrial CO 2 emissions. Identifying the driving forces behind increased CO 2 emissions in these six sectors could be valuable for the development of effective environmental policy. This study used two-tier KLEM input–output structural decomposition analysis (I-O SDA) to analyze the factors that lead to changes in CO 2 emissions. Empirical results obtained in Taiwan reveal that increased exports level and elevated domestic autonomous final demand level were the main reasons for increases in CO 2 emissions. Technological changes in materials and labor tended to decrease CO 2 emissions, while the power generation mix contributed significantly to the increase. Relevant strategies for reducing CO 2 emissions from energy-intensive sectors are also highlighted. - Highlights: • Identifying the driving forces behind increased CO 2 emissions is important. • This study uses two-tier KLEM I-O SDA to analyze the changes in CO 2 emissions. • Three issues are identified to achieve future CO 2 emissions reduction in Taiwan

  4. Effect of Leaf Water Potential on Internal Humidity and CO2 Dissolution: Reverse Transpiration and Improved Water Use Efficiency under Negative Pressure.

    Science.gov (United States)

    Vesala, Timo; Sevanto, Sanna; Grönholm, Tiia; Salmon, Yann; Nikinmaa, Eero; Hari, Pertti; Hölttä, Teemu

    2017-01-01

    The pull of water from the soil to the leaves causes water in the transpiration stream to be under negative pressure decreasing the water potential below zero. The osmotic concentration also contributes to the decrease in leaf water potential but with much lesser extent. Thus, the surface tension force is approximately balanced by a force induced by negative water potential resulting in concavely curved water-air interfaces in leaves. The lowered water potential causes a reduction in the equilibrium water vapor pressure in internal (sub-stomatal/intercellular) cavities in relation to that over water with the potential of zero, i.e., over the flat surface. The curved surface causes a reduction also in the equilibrium vapor pressure of dissolved CO 2 , thus enhancing its physical solubility to water. Although the water vapor reduction is acknowledged by plant physiologists its consequences for water vapor exchange at low water potential values have received very little attention. Consequences of the enhanced CO 2 solubility to a leaf water-carbon budget have not been considered at all before this study. We use theoretical calculations and modeling to show how the reduction in the vapor pressures affects transpiration and carbon assimilation rates. Our results indicate that the reduction in vapor pressures of water and CO 2 could enhance plant water use efficiency up to about 10% at a leaf water potential of -2 MPa, and much more when water potential decreases further. The low water potential allows for a direct stomatal water vapor uptake from the ambient air even at sub-100% relative humidity values. This alone could explain the observed rates of foliar water uptake by e.g., the coastal redwood in the fog belt region of coastal California provided the stomata are sufficiently open. The omission of the reduction in the water vapor pressure causes a bias in the estimates of the stomatal conductance and leaf internal CO 2 concentration based on leaf gas exchange

  5. Performance Evaluation of Staged Bosch Process for CO2 Reduction to Produce Life Support Consumables

    Science.gov (United States)

    Vilekar, Saurabh A.; Hawley, Kyle; Junaedi, Christian; Walsh, Dennis; Roychoudhury, Subir; Abney. Morgan B.; Mansell, James M.

    2012-01-01

    Utilizing carbon dioxide to produce water and hence oxygen is critical for sustained manned missions in space, and to support both NASA's cabin Atmosphere Revitalization System (ARS) and In-Situ Resource Utilization (ISRU) concepts. For long term missions beyond low Earth orbit, where resupply is significantly more difficult and costly, open loop ARS, like Sabatier, consume inputs such as hydrogen. The Bosch process, on the other hand, has the potential to achieve complete loop closure and is hence a preferred choice. However, current single stage Bosch reactor designs suffer from a large recycle penalty due to slow reaction rates and the inherent limitation in approaching thermodynamic equilibrium. Developmental efforts are seeking to improve upon the efficiency (hence reducing the recycle penalty) of current single stage Bosch reactors which employ traditional steel wool catalysts. Precision Combustion, Inc. (PCI), with support from NASA, has investigated the potential for utilizing catalysts supported over short-contact time Microlith substrates for the Bosch reaction to achieve faster reaction rates, higher conversions, and a reduced recycle flows. Proof-of-concept testing was accomplished for a staged Bosch process by splitting the chemistry in two separate reactors, first being the reverse water-gas-shift (RWGS) and the second being the carbon formation reactor (CFR) via hydrogenation and/or Boudouard. This paper presents the results from this feasibility study at various operating conditions. Additionally, results from two 70 hour durability tests for the RWGS reactor are discussed.

  6. Feasibility study on energy saving and reduction of CO2 emissions at Pertamina's Cilacap Refinery

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    With an objective of saving energy and reducing greenhouse gas emission, a basic survey has been performed on the atmospheric crude oil distillation units and the high vacuum distillation units at Cilacap Refinery in Indonesia. The first site survey in September 2000 has carried out a survey on the situation of the facilities and operation upon obtaining the facility data and operation information from Pertamina. As a result, it was revealed that there is a room of improvement in the heat recovery, whereas a modification design was executed on the improvement proposals on the heat exchanger system. However, the second site survey in November 2000 has revealed that Pertamina had executed in 1998 through 1999 the de-bottlenecking project on the crude oil atmospheric distillation units (two units) and the high vacuum distillation units (two units), by which the capability has been expanded, and the heat recovery rate has been increased. It is not possible to look for extremely large enhancement of the heat recovery rate beyond that point, and the reduction of CO2 emission would also be small. As a result of discussions, the present project was found capable of reducing annually the CO2 emission by 36,500 tons. (NEDO)

  7. Implications of the recent reductions in natural gas prices for emissions of CO2 from the US power sector.

    Science.gov (United States)

    Lu, Xi; Salovaara, Jackson; McElroy, Michael B

    2012-03-06

    CO(2) emissions from the US power sector decreased by 8.76% in 2009 relative to 2008 contributing to a decrease over this period of 6.59% in overall US emissions of greenhouse gases. An econometric model, tuned to data reported for regional generation of US electricity, is used to diagnose factors responsible for the 2009 decrease. More than half of the reduction is attributed to a shift from generation of power using coal to gas driven by a recent decrease in gas prices in response to the increase in production from shale. An important result of the model is that, when the cost differential for generation using gas rather than coal falls below 2-3 cents/kWh, less efficient coal fired plants are displaced by more efficient natural gas combined cycle (NGCC) generation alternatives. Costs for generation using NGCC decreased by close to 4 cents/kWh in 2009 relative to 2008 ensuring that generation of electricity using gas was competitive with coal in 2009 in contrast to the situation in 2008 when gas prices were much higher. A modest price on carbon could contribute to additional switching from coal to gas with further savings in CO(2) emissions.

  8. Remote Sensing of CO2 Absorption by Saline-Alkali Soils: Potentials and Constraints

    Directory of Open Access Journals (Sweden)

    Wenfeng Wang

    2014-01-01

    Full Text Available CO2 absorption by saline-alkali soils was recently demonstrated in the measurements of soil respiration fluxes in arid and semiarid ecosystems and hypothetically contributed to the long-thought “missing carbon sink.” This paper is aimed to develop the preliminary theory and methodology for the quantitative analysis of CO2 absorption by saline-alkali soils on regional and global scales. Both the technological progress of multispectral remote sensing over the past decades and the conjectures of mechanisms and controls of CO2 absorption by saline-alkali soils are advantageous for remote sensing of such absorption. At the end of this paper, the scheme for remote sensing is presented and some unresolved issues related to the scheme are also proposed for further investigations.

  9. Reduction of Non-CO2 Gas Emissions Through The In Situ Bioconversion of Methane

    Energy Technology Data Exchange (ETDEWEB)

    Scott, A R; Mukhopadhyay, B; Balin, D F

    2012-09-06

    The primary objectives of this research were to seek previously unidentified anaerobic methanotrophs and other microorganisms to be collected from methane seeps associated with coal outcrops. Subsurface application of these microbes into anaerobic environments has the potential to reduce methane seepage along coal outcrop belts and in coal mines, thereby preventing hazardous explosions. Depending upon the types and characteristics of the methanotrophs identified, it may be possible to apply the microbes to other sources of methane emissions, which include landfills, rice cultivation, and industrial sources where methane can accumulate under buildings. Finally, the microbes collected and identified during this research also had the potential for useful applications in the chemical industry, as well as in a variety of microbial processes. Sample collection focused on the South Fork of Texas Creek located approximately 15 miles east of Durango, Colorado. The creek is located near the subsurface contact between the coal-bearing Fruitland Formation and the underlying Pictured Cliffs Sandstone. The methane seeps occur within the creek and in areas adjacent to the creek where faulting may allow fluids and gases to migrate to the surface. These seeps appear to have been there prior to coalbed methane development as extensive microbial soils have developed. Our investigations screened more than 500 enrichments but were unable to convince us that anaerobic methane oxidation (AMO) was occurring and that anaerobic methanotrophs may not have been present in the samples collected. In all cases, visual and microscopic observations noted that the early stage enrichments contained viable microbial cells. However, as the levels of the readily substrates that were present in the environmental samples were progressively lowered through serial transfers, the numbers of cells in the enrichments sharply dropped and were eliminated. While the results were disappointing we acknowledge that

  10. Free energy landscape of electrocatalytic CO2 reduction to CO on aqueous FeN4 center embedded graphene studied by ab initio molecular dynamics simulations

    Science.gov (United States)

    Sheng, Tian; Sun, Shi-Gang

    2017-11-01

    Experiments have found that the porphyrin-like FeN4 site in Fe-N-C materials is highly efficient for the electrochemical reduction of CO2 into CO. In this work, we investigated the reduction mechanisms on FeN4 embedded graphene layer catalyst with some explicit water molecules by combining the constrained ab initio molecular dynamics simulations and thermodynamic integrations. The reaction free energy and electron transfer in each elementary step were identified. The initial CO2 activation was identified to go through the first electron transfer to form adsorbed CO2- anion and the CO desorption was the rate limiting step in the overall catalytic cycle.

  11. Gravel bar thermal variability and its potential consequences for CO2 evasion from Alpine coldwater streams

    Science.gov (United States)

    Boodoo, Kyle; Battin, Tom; Schelker, Jakob

    2017-04-01

    Gravel bars (GB) are ubiquitous in-stream structures with relatively large exposed surfaces, capable of absorbing heat and possibly acting as a heat source to the underlying hyporheic zone (HZ). The distinctive mixing of groundwater and surface water within their HZ largely determines its characteristic physical and biogeochemical properties, including temperature distribution. To study thermal variability within GBs and its possible consequences for CO2 evasion fluxes we analysed high frequency spatio-temporal data for a range of stream and atmospheric physical parameters including the vertical GB temperature, in an Alpine cold water stream (Oberer Seebach, Austria) over the course of a year. We found the vertical temperature profiles within the GB to vary seasonally and with discharge. We extended our study to 13 other gravel bars of varying physical characteristics within the surrounding Ybbs and Erlauf catchments, conducting diurnal spot samplings in summer 2016. Temperatures within the observed permanently wetted hyporheic zone (-56 to -100cm depth below GB surface) of the OSB, were warmer than both end members, surface water and groundwater >18% of the year, particularly during summer. There was a general increase in exceedance within the periodically wetted gravel bar sediment toward the gravel bar surface, further evidencing downward heat transfer to the wetted HZ. Average CO2 flux from the GB was significantly higher than that of streamwater during summer and winter, with significantly higher temperatures and CO2 outgassing rates occurring at the GB tail as compared to streamwater and the head and mid of the GB throughout the year. Higher cumulative (over 6 h) GB seasonal temperatures were associated with increased CO2 evasion fluxes within the OSB, particularly during summer. This enhanced CO2 flux may result from the input of warmer CO2-rich groundwater into the HZ in autumn, while downward heat transfer in summer may enhance GB metabolism and therefore

  12. Reduction of aerobic and lactic acid bacteria in dairy desludge using an integrated compressed CO2 and ultrasonic process.

    Science.gov (United States)

    Overton, Tim W; Lu, Tiejun; Bains, Narinder; Leeke, Gary A

    Current treatment routes are not suitable to reduce and stabilise bacterial content in some dairy process streams such as separator and bactofuge desludges which currently present a major emission problem faced by dairy producers. In this study, a novel method for the processing of desludge was developed. The new method, elevated pressure sonication (EPS), uses a combination of low frequency ultrasound (20 kHz) and elevated CO 2 pressure (50 to 100 bar). Process conditions (pressure, sonicator power, processing time) were optimised for batch and continuous EPS processes to reduce viable numbers of aerobic and lactic acid bacteria in bactofuge desludge by ≥3-log fold. Coagulation of proteins present in the desludge also occurred, causing separation of solid (curd) and liquid (whey) fractions. The proposed process offers a 10-fold reduction in energy compared to high temperature short time (HTST) treatment of milk.

  13. Origin of the Reductive Tricarboxylic Acid (rTCA Cycle-Type CO2 Fixation: A Perspective

    Directory of Open Access Journals (Sweden)

    Norio Kitadai

    2017-10-01

    Full Text Available The reductive tricarboxylic acid (rTCA cycle is among the most plausible candidates for the first autotrophic metabolism in the earliest life. Extant enzymes fixing CO2 in this cycle contain cofactors at the catalytic centers, but it is unlikely that the protein/cofactor system emerged at once in a prebiotic process. Here, we discuss the feasibility of non-enzymatic cofactor-assisted drive of the rTCA reactions in the primitive Earth environments, particularly focusing on the acetyl-CoA conversion to pyruvate. Based on the energetic and mechanistic aspects of this reaction, we propose that the deep-sea hydrothermal vent environments with active electricity generation in the presence of various sulfide catalysts are a promising setting for it to progress. Our view supports the theory of an autotrophic origin of life from primordial carbon assimilation within a sulfide-rich hydrothermal vent.

  14. Upgraded biogas from municipal solid waste for natural gas substitution and CO2 reduction – A case study of Austria, Italy, and Spain

    International Nuclear Information System (INIS)

    Starr, Katherine; Villalba, Gara; Gabarrell, Xavier

    2015-01-01

    Highlights: • Biogas can be upgraded to create biomethane, a substitute to natural gas. • Biogas upgrading was applied to landfills and anaerobic digestors in 3 countries. • Up to 0.6% of a country’s consumption of natural gas could be replaced by biomethane. • Italy could save 46% of the national CO 2 emissions attributed to the waste sector. • Scenarios were created to increase biomethane production. - Abstract: Biogas is rich in methane and can be further purified through biogas upgrading technologies, presenting a viable alternative to natural gas. Landfills and anaerobic digestors treating municipal solid waste are a large source of such biogas. They therefore offer an attractive opportunity to tap into this potential source of natural gas while at the same time minimizing the global warming impact resulting from methane emissions in waste management schemes (WMS) and fossil fuel consumption reduction. This study looks at the current municipal solid waste flows of Spain, Italy, and Austria over one year (2009), in order to determine how much biogas is generated. Then it examines how much natural gas could be substituted by using four different biogas upgrading technologies. Based on current waste generation rates, exploratory but realistic WMS were created for each country in order to maximize biogas production and potential for natural gas substitution. It was found that the potential substitution of natural gas by biogas resulting from the current WMS seems rather insignificant: 0.2% for Austria, 0.6% for Italy and 0.3% for Spain. However, if the WMS is redesigned to maximize biogas production, these figures can increase to 0.7% for Austria, 1% for Italy and 2% for Spain. Furthermore, the potential CO 2 reduction as a consequence of capturing the biogas and replacing fossil fuel can result in up to a 93% reduction of the annual national waste greenhouse gas emissions of Spain and Italy

  15. What determines urban households' willingness to pay for CO2 emission reductions in Turkey: A contingent valuation survey

    International Nuclear Information System (INIS)

    Adaman, Fikret; Karali, Nihan; Kumbaroglu, Guerkan; Or, Ilhan; Ozkaynak, Beguem; Zenginobuz, Unal

    2011-01-01

    This paper explores Turkish urban households' willingness to pay (WTP) for CO 2 emission reductions expected to result from improvements in power production. A face-to-face questionnaire, with a Contingent valuation (CV) module prepared using the double-bounded dichotomous choice elicitation framework, was administered to 2422 respondents representative of urban Turkey-a developing country with low but rapidly increasing greenhouse gas emissions. The determinants of WTP were identified by considering not only the impact of standard socio-economic factors but also the effects of environmental knowledge, attitudes and behaviour, the relevance of the identity of the collection agent (national versus international institutions) in terms of trust people have towards them, and the degree of perceived participation of others in the realization of the project. Our study confirms the existing literature in demonstrating that WTP figures reported by young and educated people that are active on environmental issues, and who also possess material security and environmental knowledge, are more likely to be high. However, their willingness to make contributions is hampered significantly by their belief that their fellow citizens will not contribute and the general lack of trust in institutions. Overall, this study may be taken as a call to eliminate governance-related uncertainties in climate change deals. - Research Highlights: → We explored the determinants of households' willingness to pay for CO 2 reductions. → We administered a contingent valuation survey to 2422 respondents in urban Turkey. → Young, educated, environmentally-knowledgeable and activist people contribute more. → Income is also found to be significant in increasing willingness to contribute. → Lack of trust in institutions and in other's participation hampers the contributions.

  16. Initial Reduction of CO2 on Pd-, Ru-, and Cu-Doped CeO2(111) Surfaces: Effects of Surface Modification on Catalytic Activity and Selectivity.

    Science.gov (United States)

    Guo, Chen; Wei, Shuxian; Zhou, Sainan; Zhang, Tian; Wang, Zhaojie; Ng, Siu-Pang; Lu, Xiaoqing; Wu, Chi-Man Lawrence; Guo, Wenyue

    2017-08-09

    Surface modification by metal doping is an effective treatment technique for improving surface properties for CO 2 reduction. Herein, the effects of doped Pd, Ru, and Cu on the adsorption, activation, and reduction selectivity of CO 2 on CeO 2 (111) were investigated by periodic density functional theory. The doped metals distorted the configuration of a perfect CeO 2 (111) by weakening the adjacent Ce-O bond strength, and Pd doping was beneficial for generating a highly active O vacancy. The analyses of adsorption energy, charge density difference, and density of states confirmed that the doped metals were conducive for enhancing CO 2 adsorption, especially for Cu/CeO 2 (111). The initial reductive dissociation CO 2 → CO* + O* on metal-doped CeO 2 (111) followed the sequence of Cu- > perfect > Pd- > Ru-doped CeO 2 (111); the reductive hydrogenation CO 2 + H → COOH* followed the sequence of Cu- > perfect > Ru- > Pd-doped CeO 2 (111), in which the most competitive route on Cu/CeO 2 (111) was exothermic by 0.52 eV with an energy barrier of 0.16 eV; the reductive hydrogenation CO 2 + H → HCOO* followed the sequence of Ru- > perfect > Pd-doped CeO 2 (111). Energy barrier decomposition analyses were performed to identify the governing factors of bond activation and scission along the initial CO 2 reduction routes. Results of this study provided deep insights into the effect of surface modification on the initial reduction mechanisms of CO 2 on metal-doped CeO 2 (111) surfaces.

  17. The potential of geological storage of CO2 in Austria: a techno-economic assessment

    NARCIS (Netherlands)

    Brüstle, Anna Katharina; Welkenhuysen, Kris; Bottig, Magdalena; Piessens, Kris; Ramirez, Andrea; Swenner, Rudy

    An impressive two-third or about 40GWh/y of electricity in Austria is produced from renewable energy sources, in particular hydro energy. For the remaining part the country depends on fossil fuels, which together with iron & steel production form the most CO2 intensive industries in Austria with a

  18. Potassium limits potential growth of bog vegetation under elevated atmospheric CO2 and N deposition

    NARCIS (Netherlands)

    Hoosbeek, M.R.; Breemen, van N.; Vasander, H.; Buttlers, A.; Berendse, F.

    2002-01-01

    The free air carbon dioxide enrichment (FACE) and N deposition experiments on four ombrotrophic bogs in Finland, Sweden, the Netherlands and Switzerland, revealed that after three years of treatment: (1) elevated atmospheric CO2 concentration had no significant effect on the biomass growth of

  19. Detecting evidence for CO2 fertilization from tree ring studies: The potential role of sampling biases

    NARCIS (Netherlands)

    Brienen, R.J.W.; Gloor, E.; Zuidema, P.A.

    2012-01-01

    Tree ring analysis allows reconstructing historical growth rates over long periods. Several studies have reported an increasing trend in ring widths, often attributed to growth stimulation by increasing atmospheric CO2 concentration. However, these trends may also have been caused by sampling

  20. The potential effect of high atmospheric CO2 on soil fungi-invertebrate interactions

    Czech Academy of Sciences Publication Activity Database

    Frouz, Jan; Nováková, Alena; Jones, H.

    2002-01-01

    Roč. 8, - (2002), s. 339-344 ISSN 1354-1013 R&D Projects: GA AV ČR IAB6066903 Institutional research plan: CEZ:AV0Z6066911 Keywords : food web * global changes * high CO2 Subject RIV: EH - Ecology, Behaviour Impact factor: 3.398, year: 2002

  1. Upgraded biogas from municipal solid waste for natural gas substitution and CO2 reduction--a case study of Austria, Italy, and Spain.

    Science.gov (United States)

    Starr, Katherine; Villalba, Gara; Gabarrell, Xavier

    2015-04-01

    Biogas is rich in methane and can be further purified through biogas upgrading technologies, presenting a viable alternative to natural gas. Landfills and anaerobic digestors treating municipal solid waste are a large source of such biogas. They therefore offer an attractive opportunity to tap into this potential source of natural gas while at the same time minimizing the global warming impact resulting from methane emissions in waste management schemes (WMS) and fossil fuel consumption reduction. This study looks at the current municipal solid waste flows of Spain, Italy, and Austria over one year (2009), in order to determine how much biogas is generated. Then it examines how much natural gas could be substituted by using four different biogas upgrading technologies. Based on current waste generation rates, exploratory but realistic WMS were created for each country in order to maximize biogas production and potential for natural gas substitution. It was found that the potential substitution of natural gas by biogas resulting from the current WMS seems rather insignificant: 0.2% for Austria, 0.6% for Italy and 0.3% for Spain. However, if the WMS is redesigned to maximize biogas production, these figures can increase to 0.7% for Austria, 1% for Italy and 2% for Spain. Furthermore, the potential CO2 reduction as a consequence of capturing the biogas and replacing fossil fuel can result in up to a 93% reduction of the annual national waste greenhouse gas emissions of Spain and Italy. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. The Tiehchanshan structure of NW Taiwan: A potential geological reservoir for CO2 sequestration

    Directory of Open Access Journals (Sweden)

    Kenn-Ming Yang

    2017-01-01

    Full Text Available The Tiehchanshan structure is the largest gas-field in the outer foothills of northwestern Taiwan and has been regarded as the best site for CO2 sequestration. This study used a grid of seismic sections and wellbore data to establish a new 3-D geometry of subsurface structure, which was combined with lithofacies characters of the target reservoir rock, the Yutengping Sandstone, to build a geological model for CO2 sequestration. On the surface, the Tiehchanshan structure is characterized by two segmented anticlines offset by a tear fault. The subsurface geometry of the Tiehchanshan structure is, however, composed of two thrust-related anticlines with opposite vergence and laterally increasing fold symmetry toward each other. The folds are softly linked via the transfer zone in the subsurface, implying that the suspected tear fault in the surface transfer zone may not exist in the subsurface. The Yutengping Sandstone is composed of several sandstone units characterized by coarsening-upward cycles. The sandstone member can be further divided into four well-defined sandstone layers, separated by laterally continuous shale layers. In view of the structural and stratigraphic characteristics, the optimum area for CO2 injection and storage is in the structurally high in the northern part of the Tiehchanshan structure. The integrity of the closure and the overlying seal are not disrupted by the pre-orogenic high-angle faults. On the other hand, a thick continuous shale layer within the Yutengping Sandstone isolates the topmost sandy layer from the underlying ones and gives another important factor to the CO2 injection simulation.

  3. CO2 Mitigation Potential of Plug-in Hybrid Electric Vehicles larger than expected.

    Science.gov (United States)

    Plötz, P; Funke, S A; Jochem, P; Wietschel, M

    2017-11-28

    The actual contribution of plug-in hybrid and battery electric vehicles (PHEV and BEV) to greenhouse gas mitigation depends on their real-world usage. Often BEV are seen as superior as they drive only electrically and do not have any direct emissions during driving. However, empirical evidence on which vehicle electrifies more mileage with a given battery capacity is lacking. Here, we present the first systematic overview of empirical findings on actual PHEV and BEV usage for the US and Germany. Contrary to common belief, PHEV with about 60 km of real-world range currently electrify as many annual vehicles kilometres as BEV with a much smaller battery. Accordingly, PHEV recharged from renewable electricity can highly contribute to green house gas mitigation in car transport. Including the higher CO 2eq emissions during the production phase of BEV compared to PHEV, PHEV show today higher CO 2eq savings then BEVs compared to conventional vehicles. However, for significant CO 2eq improvements of PHEV and particularly of BEVs the decarbonisation of the electricity system should go on.

  4. Potentialities of the atmospheric CO2 remote sensing thanks to static Fourier transform spectrometry

    International Nuclear Information System (INIS)

    Lacan, A.

    2009-04-01

    A global measurement of atmospheric CO 2 concentration is required to improve the prediction of the range of global warming. A satellite mission could provide such a measurement. CNES developed a new generation instrument dedicated to atmospheric sounding. It is a static Fourier transform spectrometer whose mass and size are smaller than those of classical spectrometers. The application of the concept for CO 2 sounding is studied thanks to an on ground experimental bread board representative of a satellite borne spectrometer. The CO 2 concentration is deduced from atmospheric spectra at 1.6 μm thanks to differential spectroscopy technique. The instrumental concept is presented. Then the conception of the spectrometer and the working procedure are described. A study of information content is done. Retrieval simulations show that an error of ±0.6 ppm can be expected, lower than the ±1 ppm goal. Finally the results of a measurement campaign are given. The retrieval precision is compatible with the objectives. Yet the instrument is also sensitive to disruptive parameters. For example deformations of the instrument could engender significant measurement errors. Instrument improvements are proposed to increase the retrieval precision. (author)

  5. Revisiting CO2 mitigation potential and costs in China's electricity sector

    International Nuclear Information System (INIS)

    Cai Wenjia; Wang Can; Chen Jining

    2010-01-01

    To improve the reliability of sectoral mitigation potential and cost analysis, this paper made an in-depth exploration into China's electricity sector's thermal efficiency and inner structure. It is found that unlike what many literatures portray, China is actually among the world's leaders in coal-fired power plants' generating efficiencies; besides, although there are still numerous small and inefficient generating units in the current generation fleet, many of them are in fact playing important roles in supporting local economic development, meeting peak load needs, balancing heat and electricity supply and providing job opportunities to the local economy, therefore their existence does not necessarily mean low-cost mitigation potential. Given the efficiency and structural characteristics of China's electricity sector, it is pointed out that some other mitigation options, such as demand side management, IGCC and renewable energy as well as the break-through of CCS technology may play an even more important role in emission reduction. Considering the significant lock-in effects in electricity sector, it is warned that China, if continues putting majority investment in large and advanced coal-fired generating units, will face another round of chasing-after for the new and advanced renewable generation technologies. Therefore China should put more efforts in renewable generation technologies now.

  6. The potential role of nuclear power in controlling CO2 emissions

    International Nuclear Information System (INIS)

    Fulkerson, W.; Jones, J.E.; Delene, J.G.; Perry, A.M.; Cantor, R.A.

    1990-01-01

    Nuclear power currently reduces CO 2 emissions from fossil fuel burning worldwide by about 8% (0.4 Gt(C)/yr). It can continue to play an important role only if it can grow substantially in the next 50 years. For such growth to occur public confidence will need to improve throughout the world. That might happen if (a) other non-fossil alternatives are inadequate to meet electricity demand growth, (b) the risks to society from global warming are perceived to be very high, (c) nuclear technology improves substantially, and (d) an international institutional setting is devised to manage the nuclear enterprise so that the technology is available to all nations while catastrophic accidents and proliferation of nuclear weapon capabilities are avoided. It seems feasible that the necessary technological and institutional advances can be devised and tested over the next 20 years. It is also plausible that the direct costs of electricity produced by the system would be in the range of 50-100 mills/kWhr (1990 dollars) delivered to the grid. In other words, the direct costs of nuclear power should not be greater than they are today. Achieving such an outcome will require aggressive technical and institutional RD ampersand D performed in a cooperative international setting. If rapid growth of nuclear power can begin again in 15-20 years it could supply 30-50% of world electricity in 50 years and cut CO 2 emission rates by up to 2.5 Gt(C)/yr. This would be a substantial contribution to controlling greenhouse gases, but it is not sufficient. Improved efficiency and various renewable energy sources must also grow rapidly if CO 2 emission rates from electricity generation are to be reduced from the current value of about 2 Gt(C)/yr. 41 refs., 4 figs., 3 tabs

  7. Climate protection with rapid payback. Energy and CO2 savings potential of industrial insulation in EU27

    Energy Technology Data Exchange (ETDEWEB)

    Neelis, M.; Blinde, P.; Overgaag, M.; Deng, Y. [Ecofys Netherlands, Utrecht (Netherlands)

    2012-06-15

    This study aims to answer the following four questions: (1) What is the energy savings and CO2 emissions mitigation potential resulting from insulating currently uninsulated parts and from better maintenance of insulation systems?; (2) What are the energy savings and CO2 mitigation potential from improving current insulation to cost-effective levels? Cost-effective insulation in this study is defined as the insulation that minimises the sum of the costs of heat loss and the costs of insulation; (3) What is the energy savings and CO2 mitigation potential from improving current insulation beyond cost-effective levels to even more energy-efficient levels? Energy-efficient insulation in this study is defined as the insulation at which the sum of the costs of heat loss and the annualised insulation investments are equal to the costs of typical current insulation while offering an additional energy savings and CO2 mitigation potential; and (4) How can these potentials best be realised? This study investigates savings potentials from improved insulation in EU industry and the power sector under realistic market conditions. Nuclear power plants and power production by renewable sources were left outside the scope of this study as well as insulations of cold applications. Case studies of insulation projects have been used to compare energy loss and investments related to different levels of insulation. The analysis was performed for three temperature levels: <100C; 100-300C and >300C. Results at the level of the case studies were extrapolated to European level using data on current energy use. Other assumptions have been made where needed on the basis of literature and expert input. All potentials are based on a 9% discount rate, an average insulation lifetime of 15 years and a 2-3% per year increase of the price of energy net of inflation.

  8. Cobalt-Doped Carbon Gels as Electro-Catalysts for the Reduction of CO2 to Hydrocarbons

    Directory of Open Access Journals (Sweden)

    Abdalla Abdelwahab

    2017-01-01

    Full Text Available Two original series of carbon gels doped with different cobalt loadings and well-developed mesoporosity, aerogels and xerogels, have been prepared, exhaustively characterized, and tested as cathodes for the electro-catalytic reduction of CO2 to hydrocarbons at atmospheric pressure. Commercial cobalt and graphite sheets have also been tested as cathodes for comparison. All of the doped carbon gels catalyzed the formation of hydrocarbons, at least from type C1 to C4. The catalytic activity depends mainly on the metal loading, nevertheless, the adsorption of a part of the products in the porous structure of the carbon gel cannot be ruled out. Apparent faradaic efficiencies calculated with these developed materials were better that those obtained with a commercial cobalt sheet as a cathode, especially considering the much lower amount of cobalt contained in the Co-doped carbon gels. The cobalt-carbon phases formed in these types of doped carbon gels improve the selectivity to C3-C4 hydrocarbons formation, obtaining even more C3 hydrocarbons than CH4 in some cases.

  9. New business models of green energy supply on the energy market with the effects of reduction of CO2

    International Nuclear Information System (INIS)

    Grozdanic, I.; Pokrovac, M.

    2015-01-01

    In this paper, new business models for renewables, which found their way to market competitiveness and which become more present on energy markets in EU will be shown. This transition, beside transition to ecological and, in the long-term, more sustainable production of energy , brought another change which has far more importance for society. New business models for investments in renewables which bring energy industry closer to citizens are being developed. Entrepreneurs, energy cooperatives and public grouped in various forms of associations in Germany own over 50 percent of renewables. Such investment models are important for society because of the development of more sustainable and just society in which citizens are included in production of electricity. Also, through these models, price of electricity is lower for end users. Besides direct collective fund investments from citizens, these types of projects are financially supported through financial instruments of the EU, but also through special bank types, such as environmental and ethical banks. These business models are long-term acceptable because of increasing involvement of renewables which results in reduction of CO2. In this paper, european models and possible models which could be used in Croatia are shown. (author).

  10. Forcings and feedbacks in the GeoMIP ensemble for a reduction in solar irradiance and increase in CO2

    Science.gov (United States)

    Huneeus, Nicolas; Boucher, Olivier; Alterskjær, Kari; Cole, Jason N. S.; Curry, Charles L.; Ji, Duoying; Jones, Andy; Kravitz, Ben; Kristjánsson, Jón Egill; Moore, John C.; Muri, Helene; Niemeier, Ulrike; Rasch, Phil; Robock, Alan; Singh, Balwinder; Schmidt, Hauke; Schulz, Michael; Tilmes, Simone; Watanabe, Shingo; Yoon, Jin-Ho

    2014-05-01

    The effective radiative forcings (including rapid adjustments) and feedbacks associated with an instantaneous quadrupling of the preindustrial CO2 concentration and a counterbalancing reduction of the solar constant are investigated in the context of the Geoengineering Model Intercomparison Project (GeoMIP). The forcing and feedback parameters of the net energy flux, as well as its different components at the top-of-atmosphere (TOA) and surface, were examined in 10 Earth System Models to better understand the impact of solar radiation management on the energy budget. In spite of their very different nature, the feedback parameter and its components at the TOA and surface are almost identical for the two forcing mechanisms, not only in the global mean but also in their geographical distributions. This conclusion holds for each of the individual models despite intermodel differences in how feedbacks affect the energy budget. This indicates that the climate sensitivity parameter is independent of the forcing (when measured as an effective radiative forcing). We also show the existence of a large contribution of the cloudy-sky component to the shortwave effective radiative forcing at the TOA suggesting rapid cloud adjustments to a change in solar irradiance. In addition, the models present significant diversity in the spatial distribution of the shortwave feedback parameter in cloudy regions, indicating persistent uncertainties in cloud feedback mechanisms.

  11. The empirical effects of a gasoline tax on CO2 emissions reductions from transportation sector in Korea

    International Nuclear Information System (INIS)

    Kim, Young-Duk; Han, Hyun-Ok; Moon, Young-Seok

    2011-01-01

    The introduction of carbon tax is expected to mitigate GHG emissions cost-effectively. With this expectation identifying the impacts of carbon tax on energy demand and GHG emission reductions is an interesting issue. One of the basic methods of estimating these impacts is using the price elasticity. There are, however, some unanswered questions regarding the use of price elasticity. First, which elasticity estimates are appropriate to measure the impacts of carbon tax on energy demand? The existing estimates are estimated in the presence of a substitute. To assess the impact of carbon tax could we use these estimates? Second, how can we compromise the differences among the existing estimates depending on estimation methods and specifications? For example, how can we accommodate the difference in the estimates from the regional panel specification and the aggregate specification? This paper tries to answer these questions with the price elasticity of gasoline demand. With an appropriate price elasticity, we show how much gasoline consumption and GHG emissions are reduced by carbon tax for different scenarios of carbon tax rate. - Research highlights: →We offer an appropriate estimate for evaluating the effects of carbon tax. →We estimate the price elasticity of gasoline with instrument variables. →We measure the tax effects on CO 2 emissions from transportation sector.

  12. Performance evaluation of non-thermal plasma on particulate matter, ozone and CO2 correlation for diesel exhaust emission reduction

    DEFF Research Database (Denmark)

    Babaie, Meisam; Davari, Pooya; Talebizadeh, Poyan

    2015-01-01

    This study is seeking to investigate the effect of non-thermal plasma technology in the abatement of particulate matter (PM) from the actual diesel exhaust. Ozone (O3) strongly promotes PM oxidation, the main product of which is carbon dioxide (CO2). PM oxidation into the less harmful product (CO2...

  13. Effects of composition of the micro porous layer and the substrate on performance in the electrochemical reduction of CO2 to CO

    Science.gov (United States)

    Kim, Byoungsu; Hillman, Febrian; Ariyoshi, Miho; Fujikawa, Shigenori; Kenis, Paul J. A.

    2016-04-01

    With the development of better catalysts, mass transport limitations are becoming a challenge to high throughput electrochemical reduction of CO2 to CO. In contrast to optimization of electrodes for fuel cells, optimization of gas diffusion electrodes (GDE) - consisting of a carbon fiber substrate (CFS), a micro porous layer (MPL), and a catalyst layer (CL) - for CO2 reduction has not received a lot of attention. Here, we studied the effect of the MPL and CFS composition on cathode performance in electroreduction of CO2 to CO. In a flow reactor, optimized GDEs exhibited a higher partial current density for CO production than Sigracet 35BC, a commercially available GDE. By performing electrochemical impedance spectroscopy in a CO2 flow reactor we determined that a loading of 20 wt% PTFE in the MPL resulted in the best performance. We also investigated the influence of the thickness and wet proof level of CFS with two different feeds, 100% CO2 and the mixture of 50% CO2 and N2, determining that thinner and lower wet proofing of the CFS yields better cathode performance than when using a thicker and higher wet proof level of CFS.

  14. Potential advantages of coupling supercritical CO2 Brayton cycle to water cooled small and medium size reactor

    International Nuclear Information System (INIS)

    Yoon, Ho Joon; Ahn, Yoonhan; Lee, Jeong Ik; Addad, Yacine

    2012-01-01

    Highlights: ► S-CO 2 cycle as candidate for SMS. ► MATLAB code used for S-CO 2 cycle analysis. ► Pressure ratio and split ratio comparison analyzed. - Abstract: The supercritical carbon dioxide (S-CO 2 ) Brayton cycle is being considered as a favorable candidate for the next generation nuclear reactors power conversion systems. Major benefits of the S-CO 2 Brayton cycle compared to other Brayton cycles are: (1) high thermal efficiency in relatively low turbine inlet temperature, (2) compactness of the turbomachineries and heat exchangers and (3) simpler cycle layout at an equivalent or superior thermal efficiency. However, these benefits can be still utilized even in the water-cooled reactor technologies under special circumstances. A small and medium size water-cooled nuclear reactor (SMR) has been gaining interest due to its wide range of application such as electricity generation, seawater desalination, district heating and propulsion. Another key advantage of a SMR is that it can be transported from one place to another mostly by maritime transport due to its small size, and sometimes even through a railway system. Therefore, the combination of a S-CO 2 Brayton cycle with a SMR can reinforce any advantages coming from its small size if the S-CO 2 Brayton cycle has much smaller size components, and simpler cycle layout compared to the currently considered steam Rankine cycle. In this paper, SMART (System-integrated Modular Advanced ReacTor), a 330 MW th integral reactor developed by KAERI (Korea Atomic Energy Institute) for multipurpose utilization, is considered as a potential candidate for applying the S-CO 2 Brayton cycle and advantages and disadvantages of the proposed system will be discussed in detail. In consideration of SMART condition, the turbine inlet pressure and size of heat exchangers are analyzed by using in-house code developed by KAIST–Khalifa University joint research team. According to the cycle evaluation, the maximum cycle efficiency

  15. Modeling Effects of Bicarbonate Release on Carbonate Chemistry and pH of the North Sea: A Pilot Study for Atmospheric CO2 Reduction

    Science.gov (United States)

    Lettmann, K.; Kirchner, J.; Schnetger, B.; Wolff, J. O.; Brumsack, H. J.

    2016-12-01

    Rising CO2-emissions accompanying the industrial revolution are the main drivers for climate change and ocean acidification. Several methods have been developed to capture CO2 from effluents and reduce emission. Here, we consider a promising approach that mimics natural limestone weathering: CO2 in effluent gas streams reacts with calcium carbonate in a limestone suspension. The resulting bicarbonate-rich solution can be released into natural systems. In comparison to classical carbon capture and storage (CCS) methods this artificial limestone weathering is cheaper and does not involve using toxic chemical compounds. Additionally there is no need for the controversially discussed storage of CO2 underground. The reduction of CO2-emissions becomes more important for European industries as the EU introduced a system that limits the amount of allowable CO2-emissions. Therefore, large CO2 emitters are forced to find cheap methods for emission reduction, as they often cannot circumvent CO2-production. The method mentioned above is especially of interest for power plants located close to the coast that are already using seawater for cooling purposes. Thus, it is important to estimate the environmental effects if several coastal power plants will release high amounts of bicarbonate-rich waters into coastal waters, e.g. the North Sea. In a first pilot study, the unstructured-grid finite-volume community ocean model (FVCOM) was combined with a chemical submodul (mocsy 2.0) to model the hydrodynamic circulation and mixing of bicarbonate-rich effluents from a gas power plant located at the German North Sea coast. Here, we present the first preliminary results of this project, which include modelled changes of the North Sea carbonate system and changes in pH value after the introduction of these bicarbonate-rich waters on short time scales up to one year.

  16. Methodology for Examining Potential Technology Breakthroughs for Mitigating CO2 and Application to Centralized Solar Photovoltaics

    Science.gov (United States)

    Aggressive reductions in US greenhouse gas emissions will require radical changes in how society generates and uses energy. Technological breakthroughs will be necessary if we are to make this transition cost effectively. With limited resources, understanding the breakthrough pot...

  17. Energy efficiency and CO_2 mitigation potential of the Turkish iron and steel industry using the LEAP (long-range energy alternatives planning) system

    International Nuclear Information System (INIS)

    Ates, Seyithan A.

    2015-01-01

    With the assistance of the LEAP (long-range energy alternatives planning) energy modeling tool, this study explores the energy efficiency and CO_2 emission reduction potential of the iron and steel industry in Turkey. With a share of 35%, the steel and iron industry is considered as the most energy-consuming sector in Turkey. The study explores that the energy intensity rate can be lowered by 13%, 38% and 51% in SEI (slow-speed energy efficiency improvement), AEI (accelerating energy efficiency improvement) and CPT (cleaner production and technology scenario) scenarios, respectively. Particularly the projected aggregated energy savings of the scenarios CPT and AES are very promising with saving rates of 33.7% and 23% respectively. Compared to baseline scenarios, energy efficiency improvements correspond to economic potential of 0.1 billion dollars for SEI, 1.25 dollars for AEI and 1.8 billion dollars for CPT scenarios annually. Concerning GHG (greenhouse gas) emissions, in 2030 the iron and steel industry in Turkey is estimated to produce 34.9 MtCO_2 in BAU (business-as-usual scenario), 32.5 MtCO_2 in SEI, 24.6 MtCO_2 in AEI and 14.5 MtCO_2 in CPT a scenario which corresponds to savings of 9%–39%. The study reveals that energy consumption and GHG emissions of the iron and steel industry can be lowered significantly if the necessary measures are implemented. It is expected that this study will fill knowledge gaps pertaining to energy efficiency potential in Turkish energy intensive industries and help stakeholders in energy intensive industries to realize the potential for energy efficiency and GHG mitigation. - Highlights: • This paper explores energy efficiency potential of iron and Steel industry in Turkey. • We applied the LEAP modeling to forecast future developments. • Four different scenarios have been developed for the LEAP modeling. • There is a huge potential for energy efficiency and mitigation of GHG emissions.

  18. Geomechanical Modeling of Fault Responses and the Potential for Notable Seismic Events during Underground CO2 Injection

    Science.gov (United States)

    Rutqvist, J.; Cappa, F.; Mazzoldi, A.; Rinaldi, A.

    2012-12-01

    The importance of geomechanics associated with large-scale geologic carbon storage (GCS) operations is now widely recognized. There are concerns related to the potential for triggering notable (felt) seismic events and how such events could impact the long-term integrity of a CO2 repository (as well as how it could impact the public perception of GCS). In this context, we review a number of modeling studies and field observations related to the potential for injection-induced fault reactivations and seismic events. We present recent model simulations of CO2 injection and fault reactivation, including both aseismic and seismic fault responses. The model simulations were conducted using a slip weakening fault model enabling sudden (seismic) fault rupture, and some of the numerical analyses were extended to fully dynamic modeling of seismic source, wave propagation, and ground motion. The model simulations illustrated what it will take to create a magnitude 3 or 4 earthquake that would not result in any significant damage at the groundsurface, but could raise concerns in the local community and could also affect the deep containment of the stored CO2. The analyses show that the local in situ stress field, fault orientation, fault strength, and injection induced overpressure are critical factors in determining the likelihood and magnitude of such an event. We like to clarify though that in our modeling we had to apply very high injection pressure to be able to intentionally induce any fault reactivation. Consequently, our model simulations represent extreme cases, which in a real GCS operation could be avoided by estimating maximum sustainable injection pressure and carefully controlling the injection pressure. In fact, no notable seismic event has been reported from any of the current CO2 storage projects, although some unfelt microseismic activities have been detected by geophones. On the other hand, potential future commercial GCS operations from large power plants

  19. An assessment of potential CO2 Sources throughout the Illinois Basin Subtask 5.1 – CO2 Source Assessment Topical Report

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Vinodkumar [University of Illinois; O?Brien, Kevin; Korose, Christopher

    2018-05-09

    Large-scale anthropogenic CO2 sources (>100,000 tonnes/year) were catalogued and assessed for the Illinois East Sub-Basin project area. The portfolio of sources is quite diverse, and contains not only fossil-based power generation facilities but also ethanol, chemical, and refinery facilities. Over 60% of the facilities are relatively new (i.e. post year 2000 construction) hence increasing the likelihood that retrofitting the facility with a carbon capture plant is feasible. Two of the facilities have indicated interest in being “early adopters” should the CarbonSAFE project eventually transition to a build and operate phase: the Prairie State Generating Company’s electricity generation facility near Marissa, Illinois, and Quasar Syngas, LLC’s Wabash ammonia/direct-reduced iron plant, currently in development north of Terre Haute, Indiana.

  20. Photocatalytic reduction of CO2 to CO over copper decorated g-C3N4 nanosheets with enhanced yield and selectivity

    Science.gov (United States)

    Shi, Guodong; Yang, Lin; Liu, Zhuowen; Chen, Xiao; Zhou, Jianqing; Yu, Ying

    2018-01-01

    Photocatalytic reduction of CO2 to fuel has attracted considerable attention due to the consumption of fossil fuels and serious environmental problems. Although there are many photocatalysts reported for CO2 reduction, the improvement of activity and selectivity is still in great need of. In this work, a series of Cu nanoparticle decorated g-C3N4 nanosheets with different Cu loadings were fabricated by a facile secondary calcination and subsequent microwave hydrothermal method. The designed catalysts shown good photocatalytic activity and selectivity for CO2 reduction to CO. The optimal sample exhibited a 3-fold augmentation of the CO yield in comparison with pristine g-C3N4 under visible light. It is revealed that with the loading of Cu nanoparticles, the resulting photocatalyst possessed an improved charge carrier transfer and separation efficiency as well as increased surface reactive sites, resulting in a significant enhancement of CO yield. It is anticipated that the designed Cu/C3N4 photocatalyst may provide new insights for two dimensional layer materials and non-noble particles applied to CO2 reduction.

  1. Predicting the ultimate potential of natural gas SOFC power cycles with CO2 capture - Part A: Methodology and reference cases

    Science.gov (United States)

    Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.

    2016-08-01

    Driven by the search for the highest theoretical efficiency, in the latest years several studies investigated the integration of high temperature fuel cells in natural gas fired power plants, where fuel cells are integrated with simple or modified Brayton cycles and/or with additional bottoming cycles, and CO2 can be separated via chemical or physical separation, oxy-combustion and cryogenic methods. Focusing on Solid Oxide Fuel Cells (SOFC) and following a comprehensive review and analysis of possible plant configurations, this work investigates their theoretical potential efficiency and proposes two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs integrated with a steam turbine or gas turbine cycle. The SOFC works at atmospheric or pressurized conditions and the resulting power plant exceeds 78% LHV efficiency without CO2 capture (as discussed in part A of the work) and 70% LHV efficiency with substantial CO2 capture (part B). The power plants are simulated at the 100 MW scale with a complete set of realistic assumptions about fuel cell (FC) performance, plant components and auxiliaries, presenting detailed energy and material balances together with a second law analysis.

  2. The effect of CO2, H2O and SO2 on the kinetics of NO reduction by CH4 over La2O3

    International Nuclear Information System (INIS)

    Toops, Todd J.; Walters, Arden B.; Vannice, M.A.

    2002-01-01

    The effect of CO 2 , H 2 O and SO 2 on the kinetics of NO reduction by CH 4 over unsupported La 2 O 3 has been examined between 773 and 973K in the presence of O 2 in the feed. La 2 O 3 can maintain a stable, high specific activity (mol/(sm 2 )) for NO reduction with high concentrations of CO 2 and H 2 O in the feed; however, either of these two products reversibly inhibits the activity by about one-half in the presence of excess O 2 . The catalyst is poisoned by SO 2 at these temperatures and an oxysulfate phase is formed, but partial regeneration can be achieved at 1023K. CO 2 in the feed causes the formation of lanthanum oxycarbonate, which reverts to La 2 O 3 when CO 2 is removed, but no bulk La oxyhydroxide is detected after quenching with H 2 O in the feed. The influence of CO 2 and H 2 O on kinetic behavior can be described by assuming they compete with reactants for adsorption on surface sites, including them in the site balance equation, and using the rate expression proposed previously for NO reduction by CH 4 in excess O 2 . With O 2 in the feed, integral conversions of CH 4 and O 2 frequently occurred due to the direct combustion of CH 4 by O 2 , although NO conversions remained differential; thus, an integral reactor model was chosen to analyze the data which utilized a recently determined rate equation for CH 4 combustion on La 2 O 3 in conjunction with a previously proposed model for NO reduction by CH 4 . The following rate expression described the rate of N 2 formation: N 2 T = ' NO P NO P CH 4 P O 2 0.5 / 1 + K NO P NO + K CH 4 P CH 4 + K O 2 0.5 P O 2 0.5 + K CO 2 P CO 2 + K H 2 O P H 2 O 2 . It gave a good fit to the experimental rate data for NO reduction, as well as providing enthalpies and entropies of adsorption obtained from the fitting parameters that demonstrated thermodynamic consistency and were similar to previous values. The heats of adsorption were altered somewhat when either CO 2 or H 2 O was added to the feed, and the following

  3. Quantification of oil recovery efficiency, CO 2 storage potential, and fluid-rock interactions by CWI in heterogeneous sandstone oil reservoirs

    DEFF Research Database (Denmark)

    Seyyedi, Mojtaba; Sohrabi, Mehran; Sisson, Adam

    2017-01-01

    Significant interest exists in improving recovery from oil reservoirs while addressing concerns about increasing CO2 concentrations in the atmosphere. The combination of Enhanced Oil Recovery (EOR) and safe geologic storage of CO2 in oil reservoirs is appealing and can be achieved by carbonated (CO...... for oil recovery and CO2 storage potential on heterogeneous cores. Since not all the oil reservoirs are homogenous, understanding the potential of CWI as an integrated EOR and CO2 storage scenario in heterogeneous oil reservoirs is essential....

  4. Potential forcing of CO2, technology and climate changes in maize (Zea mays) and bean (Phaseolus vulgaris) yield in southeast Brazil

    International Nuclear Information System (INIS)

    Costa, L C; Justino, F; Oliveira, L J C; Sediyama, G C; Lemos, C F; Ferreira, W P M

    2009-01-01

    Based upon sensitivity experiments, this study aims to investigate the impact of increased atmospheric CO 2 concentration, climate changes, and ongoing technological advancements on bean (Phaseolus vulgaris) and maize (Zea mays) yield. This investigation assumes that the atmospheric CO 2 concentration evolves according to the A2 scenario. For these analyses we have used climate data as projected by climate simulations conducted with the HadCM3 climate model for both present day and greenhouse warming conditions. The results demonstrated that warming conditions associated with increased greenhouse gases as delivered by the HadCM3 model lead to reductions in the potential productivity of maize and beans for the years 2050 and 2080 by up to 30%. This thermal response is, however, damped by the highly efficient CO 2 fertilization effect which is expected to increase bean productivity as compared to present day conditions. A similar investigation for maize yield revealed a different picture. It has been found that the CO 2 fertilization feedback is much weaker and cannot cancel out the thermal effect. We have found, therefore, that climate changes as simulated to occur in the future are not favorable for increasing the maize yield in southeast Brazil. By the inclusion of the third forcing evaluated, representing technological advancements, it is demonstrated that improvements in the crop system reduce the negative effect associated with warmer climate conditions for both crops. We conclude that appropriate soil and technological management as well as genetic improvements may very likely induce an increase in bean and maize yield despite the unfavorable future climate conditions.

  5. Temporal and Spatial Variations in Provincial CO2 Emissions in China from 2005 to 2015 and Assessment of a Reduction Plan

    Directory of Open Access Journals (Sweden)

    Xuankai Deng

    2015-05-01

    Full Text Available This study calculated the provincial carbon dioxide (CO2 emissions in China, analyzed the temporal and spatial variations in emissions, and determined the emission intensity from 2005 to 2015. The total emissions control was forecasted in 2015, and the reduction pressure of the 30 provinces in China was assessed based on historical emissions and the 12th five-year (2011–2015 reduction plan. Results indicate that CO2 emissions eventually increased and gradually decreased from east to west, whereas the emission intensity ultimately decreased and gradually increased from south to north. By the end of 2015, the total control of provincial emissions will increase significantly compared to the 2010 level, whereas the emission intensity will decrease. The provinces in the North, East, and South Coast regions will maintain the highest emission levels. The provinces in the Southwest and Northwest regions will experience a rapid growth rate of emissions. However, the national emission reduction target will nearly be achieved if all provinces can implement reduction targets as planned. Pressure indices show that the South Coast and Northwest regions are confronted with a greater reduction pressure of emission intensity. Finally, policy implications are provided for CO2 reductions in China.

  6. Long term energy and materials strategies for reduction of industrial CO2 emissions. A case study for the iron and steel industry

    International Nuclear Information System (INIS)

    Gielen, D.J.

    1997-01-01

    Greenhouse gas emissions emerged in the last decade as a key environmental problem on the political agenda. The most important greenhouse gas is carbon dioxide (CO 2 ). This gas results from the combustion of fossil fuels (natural gas, oil and coal). As a consequence, greenhouse gas emission reduction is closely related to energy policies. Even a stabilization of the atmospheric CO 2 concentrations at a level of 750 ppm (parts per million), more than twice the current level, implies a reduction of global emissions by 50% in the next century. The world population will simultaneously double and the capita energy consumption will increase. As a consequence, the Western industrialized countries will have to reduce their per capita emissions by more than a factor four. Such a policy goal will significantly affect the future industrial production structure. Approximately 4% of the global CO 2 emissions can be attributed to the production of iron and steel. This sector is the most important industrial source of CO 2 . The case study for the iron and steel industry will be discussed in this paper in order to illustrate the impact of significant CO 2 emission mitigation on the industry. The goal is to show the consequences of CO 2 policies for R and D planning and investment decisions. The notion that the iron and steel industry will be affected by CO 2 policies is not new; a number of studies have addressed this issue before. These studies have compared steel production technologies and emission reduction options within the iron and steel production sector. In this paper, the emission reduction in the iron and steel industry is analyzed within the framework of the changing (inter-)national energy and materials system configuration. This includes all production, conversion and consumption processes. The impact of CO 2 policies on the optimal choice of steel production technologies and on the competitiveness of steel compared to other materials will be discussed. This paper

  7. Energy consumption and CO2 emissions of industrial process technologies. Saving potentials, barriers and instruments

    International Nuclear Information System (INIS)

    Fleiter, Tobias; Schlomann, Barbara; Eichhammer, Wolfgang

    2013-01-01

    Which contribution can the increase of energy efficiency achieve in the industry energy for the energy transition in Germany? To answer this question a model-based analysis of existing energy efficiency potentials of the energy-intensive industries is performed, which account for about 70% of the total energy demand of the industry. Based on this industry for each sector are instruments proposed for the implementation of the calculated potential and to overcome the existing barriers. [de

  8. Non-sensitized selective photochemical reduction of CO2 to CO under visible light with an iron molecular catalyst.

    Science.gov (United States)

    Rao, Heng; Bonin, Julien; Robert, Marc

    2017-03-02

    A substituted tetraphenyl iron porphyrin, bearing positively charged trimethylammonio groups at the para position of each phenyl ring, demonstrates its ability as a homogeneous molecular catalyst to selectively reduce CO 2 to CO under visible light irradiation in organic media without the assistance of a sensitizer and no competitive hydrogen evolution for several days.

  9. Formulation of a Network and the Study of Reaction Paths for the Sustainable Reduction of CO2 Emissions

    DEFF Research Database (Denmark)

    Frauzem, Rebecca; Kongpanna, Pichayapan; Roh, Kosan

    and commercial processes. Within these there are high-purity emissions and low-purity emissions. Rather than sending these to the atmosphere, it is possible to collect them and use them for other purposes. Targeting some of the largest contributors: power generation, manufacturing, chemical industry...... amounts of CO2 and other greenhouse gases, and creating more energy efficient processes....

  10. Localized innovation, localized diffusion and the environment : an analysis of reductions of CO(2) emissions by passenger cars

    NARCIS (Netherlands)

    Los, B.; Verspagen, B.

    We investigate technological change with regard to CO(2) emissions by passenger cars, using a Free Disposal Hull methodology to estimate technological frontiers. We have a sample of cars available in the UK market in the period 2000-2007. Our results show that the rates of technological change

  11. Market penetration speed and effects on CO2 reduction of electric vehicles and plug-in hybrid electric vehicles in Japan

    International Nuclear Information System (INIS)

    Yabe, Kuniaki; Shinoda, Yukio; Seki, Tomomichi; Tanaka, Hideo; Akisawa, Atsushi

    2012-01-01

    Abstarct: In order to reduce CO 2 emissions in the passenger vehicle sector, mass introduction of electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs) is required despite their high battery costs. This paper forecasts the rate at which EV/PHEV will penetrate into the market in the future and the effects of that spread on CO 2 reduction by using a learning curve for lithium-ion batteries, distribution of daily travel distance for each vehicle, and an optimal power generation planning model for charging vehicles. Taking into consideration each driver's economical viewpoint, the speed at which the EV/PHEV share of the new passenger vehicle market grows is fairly slow. The optimum calculation in our base case shows that the share of EV/PHEV is only a quarter even in 2050. However, the initial price and progress rate of batteries have a great effect on this share. Therefore, long-term economic support from the government and significant R and D innovation are required to reduce CO 2 drastically through cutting down battery price. The results also show how much the CO 2 emission intensity of power generation affects the CO 2 reduction rate by introducing EV/PHEV. - Highlights: ► Authors minimized the total cost of vehicle and power supply sectors until 2050. ► Simulation results show the penetration speed of PHEVs/EVs is not so fast. ► To accelerate it and reduce CO 2 , subsidies and innovations are required. ► The introduction of PHEVs/EVs is still reasonable even after the nuclear accident.

  12. Energy Efficiency instead of CO2 levy

    International Nuclear Information System (INIS)

    Uetz, R.

    2005-01-01

    This article takes a look at ways of avoiding a future, planned Swiss CO 2 levy by improving the efficiency of energy use. The political situation concerning the reduction of CO 2 emissions in Switzerland is reviewed and the likeliness of the introduction of a CO 2 levy is discussed. Strategies for the reduction of fossil fuel consumption and therefore of CO 2 emissions are looked at, including process optimisation. Recommendations are made on how to approach this work systematically - data collection, assessment of the potential for reduction and the planning of measures to be taken are looked at. The high economic efficiency of immediate action is stressed and typical middle and long-term measures are listed

  13. CO2-induced pH reduction increases physiological toxicity of nano-TiO2 in the mussel Mytilus coruscus

    Science.gov (United States)

    Hu, Menghong; Lin, Daohui; Shang, Yueyong; Hu, Yi; Lu, Weiqun; Huang, Xizhi; Ning, Ke; Chen, Yimin; Wang, Youji

    2017-01-01

    The increasing usage of nanoparticles has caused their considerable release into the aquatic environment. Meanwhile, anthropogenic CO2 emissions have caused a reduction of seawater pH. However, their combined effects on marine species have not been experimentally evaluated. This study estimated the physiological toxicity of nano-TiO2 in the mussel Mytilus coruscus under high pCO2 (2500-2600 μatm). We found that respiration rate (RR), food absorption efficiency (AE), clearance rate (CR), scope for growth (SFG) and O:N ratio were significantly reduced by nano-TiO2, whereas faecal organic weight rate and ammonia excretion rate (ER) were increased under nano-TiO2 conditions. High pCO2 exerted lower effects on CR, RR, ER and O:N ratio than nano-TiO2. Despite this, significant interactions of CO2-induced pH change and nano-TiO2 were found in RR, ER and O:N ratio. PCA showed close relationships among most test parameters, i.e., RR, CR, AE, SFG and O:N ratio. The normal physiological responses were strongly correlated to a positive SFG with normal pH and no/low nano-TiO2 conditions. Our results indicate that physiological functions of M. coruscus are more severely impaired by the combination of nano-TiO2 and high pCO2.

  14. Basic investigation on promotion of joint implementation in fiscal 2000. Survey on energy saving and CO2 emission reduction in Cilacap Refinery; 2000 nendo kyodo jisshi nado suishin kiso chosa hokokusho. Cilacap seiyusho ni okeru shoene CO2 sakugen chosa

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    With an objective of saving energy and reducing greenhouse gas emission, a basic survey has been performed on the atmospheric crude oil distillation units and the high vacuum distillation units at Cilacap Refinery in Indonesia. The first site survey in September 2000 has carried out a survey on the situation of the facilities and operation upon obtaining the facility data and operation information from Pertamina. As a result, it was revealed that there is a room of improvement in the heat recovery, whereas a modification design was executed on the improvement proposals on the heat exchanger system. However, the second site survey in November 2000 has revealed that Pertamina had executed in 1998 through 1999 the de-bottlenecking project on the crude oil atmospheric distillation units (two units) and the high vacuum distillation units (two units), by which the capability has been expanded, and the heat recovery rate has been increased. It is not possible to look for extremely large enhancement of the heat recovery rate beyond that point, and the reduction of CO2 emission would also be small. As a result of discussions, the present project was found capable of reducing annually the CO2 emission by 36,500 tons. (NEDO)

  15. Exploring the macro-scale CO_2 mitigation potential of photovoltaics and wind energy in Europe's energy transition

    International Nuclear Information System (INIS)

    Usubiaga, Arkaitz; Acosta-Fernández, José; McDowall, Will; Li, Francis G.N.

    2017-01-01

    Replacing traditional technologies by renewables can lead to an increase of emissions during early diffusion stages if the emissions avoided during the use phase are exceeded by those associated with the deployment of new units. Based on historical developments and on counterfactual scenarios in which we assume that selected renewable technologies did not diffuse, we conclude that onshore and offshore wind energy have had a positive contribution to climate change mitigation since the beginning of their diffusion in EU27. In contrast, photovoltaic panels did not pay off from an environmental standpoint until very recently, since the benefits expected at the individual plant level were offset until 2013 by the CO_2 emissions related to the construction and deployment of the next generation of panels. Considering the varied energy mixes and penetration rates of renewable energies in different areas, several countries can experience similar time gaps between the installation of the first renewable power plants and the moment in which the emissions from their infrastructure are offset. The analysis demonstrates that the time-profile of renewable energy emissions can be relevant for target-setting and detailed policy design, particularly when renewable energy strategies are pursued in concert with carbon pricing through cap-and-trade systems. - Highlights: • There is a time gap between the deployment of renewables and net CO2 mitigation. • Offshore wind energy contributes to net emission reductions in the EU27 since 2004. • PV panels contribute to net emission reductions in the EU27 since 2013. • The time-profile of renewable energy emissions is not usually considered in policy-design. • But it is important when renewable energy strategies are combined with carbon pricing.

  16. Assessment of the potential for geological storage of CO2 in the vicinity of Moneypoint, Co. Clare, Ireland

    NARCIS (Netherlands)

    Farrelly, I.; Loske, B.; Neele, F.; Holdstock, M.

    2011-01-01

    The largest single point CO2 emitter in Ireland, the Moneypoint Power Station (3.95 Mt CO2 per annum), is located in Co. Clare and geologically lies within the Clare Basin. In terms of the economics of transportation of CO2 from Moneypoint, a possible local storage site would be favoured. The study

  17. Reduction of CO2 emissions from road transport in cities impact of dynamic route guidance system on greenhouse gas emission

    CERN Document Server

    Markiewicz, Michal

    2017-01-01

    Michal Markiewicz presents the outcomes of his research regarding the influence of dynamic route guidance system on overall emission of carbon dioxide from road transport in rural areas. Sustainable transportation in smart cities is a big challenge of our time, but before electric vehicles replace vehicles that burn fossil fuels we have to think about traffic optimization methods that reduce the amount of greenhouse gas emissions. Contents Comparison of Travel Time Measurements Using Floating Car Data and Intelligent Infrastructure Integration of Cellular Automata Traffic Simulator with CO2 Emission Model Impact of Dynamic Route Guidance System on CO2 Emission Naxos Vehicular Traffic Simulator Target Groups Lecturers and students of computer science, transportation and logistics Traffic engineers The Author Dr. Michal Markiewicz defended his PhD thesis in computer science at the University of Bremen,TZI Technologie-Zentrum Informatik und Informationstechnik, Germany. Currently, he is working on commercializat...

  18. Localized Innovation, Localized Diffusion and the Environment: An Analysis of CO2 Emission Reductions by Passenger Cars, 2000-2007

    OpenAIRE

    Los, Bart; Verspagen, Bart

    2008-01-01

    We investigate technological change with regard to CO2 emissions by passenger cars, using a Free Disposal Hull methodology to estimate technological frontiers. We have a sample of cars available in the UK market in the period 2000 – 2007. Our results show that the rates of technological change (frontier movement) and diffusion (distance to frontier at the car brand level) differ substantial between segments of the car market. We conclude that successful policies should be aimed at diffusion o...

  19. Regional Opportunities for Carbon Dioxide Capture and Storage in China: A Comprehensive CO2 Storage Cost Curve and Analysis of the Potential for Large Scale Carbon Dioxide Capture and Storage in the People’s Republic of China

    Energy Technology Data Exchange (ETDEWEB)

    Dahowski, Robert T.; Li, Xiaochun; Davidson, Casie L.; Wei, Ning; Dooley, James J.

    2009-12-01

    This study presents data and analysis on the potential for carbon dioxide capture and storage (CCS) technologies to deploy within China, including a survey of the CO2 source fleet and potential geologic storage capacity. The results presented here indicate that there is significant potential for CCS technologies to deploy in China at a level sufficient to deliver deep, sustained and cost-effective emissions reductions for China over the course of this century.

  20. Ni-Nanocluster Modified Black TiO2 with Dual Active Sites for Selective Photocatalytic CO2 Reduction.

    Science.gov (United States)

    Billo, Tadesse; Fu, Fang-Yu; Raghunath, Putikam; Shown, Indrajit; Chen, Wei-Fu; Lien, Hsiang-Ting; Shen, Tzu-Hsien; Lee, Jyh-Fu; Chan, Ting-Shan; Huang, Kuo-You; Wu, Chih-I; Lin, M C; Hwang, Jih-Shang; Lee, Chih-Hao; Chen, Li-Chyong; Chen, Kuei-Hsien

    2018-01-01

    One of the key challenges in artificial photosynthesis is to design a photocatalyst that can bind and activate the CO 2 molecule with the smallest possible activation energy and produce selective hydrocarbon products. In this contribution, a combined experimental and computational study on Ni-nanocluster loaded black TiO 2 (Ni/TiO 2[Vo] ) with built-in dual active sites for selective photocatalytic CO 2 conversion is reported. The findings reveal that the synergistic effects of deliberately induced Ni nanoclusters and oxygen vacancies provide (1) energetically stable CO 2 binding sites with the lowest activation energy (0.08 eV), (2) highly reactive sites, (3) a fast electron transfer pathway, and (4) enhanced light harvesting by lowering the bandgap. The Ni/TiO 2[Vo] photocatalyst has demonstrated highly selective and enhanced photocatalytic activity of more than 18 times higher solar fuel production than the commercial TiO 2 (P-25). An insight into the mechanisms of interfacial charge transfer and product formation is explored. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Optimization of Electricity Generation Schemes in the Java-Bali Grid System with Co2 Reduction Consideration

    Directory of Open Access Journals (Sweden)

    Farizal Farizal

    2016-08-01

    Full Text Available This research considers the problem of reducing CO2 emissions from the Java-Bali power grid system that consists of a variety of power-generating plants: coal-fired, natural gas, oil, and renewable energy (PV, geothermal, hydroelectric, wind, and landfill gas. The problem is formulated as linear programming and solved using LINGO 10. The model was developed for a nation to meet a specified CO2 emission target. Two carbon dioxide mitigation options are considered in this study, i.e. fuel balancing and fuel switching. In order to reduce the CO2 emissions by 26% in 2021, State Electric Supply Company (PLN has to generate up to 30% of electricity from renewable energy (RE, and the cost of electricity (COE is expected to increase to 617.77 IDR per kWh for a fuel balancing option, while for fuel switching option, PLN has to generate 29% of electricity from RE, and the COE is expected to increase to 535.85 IDR per kWh.

  2. Leakage Risk Assessment for a Potential CO2 Storage Project in Saskatchewan, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Houseworth, J.E.; Oldenburg, C.M.; Mazzoldi, A.; Gupta, A.K.; Nicot, J.-P.; Bryant, S.L.

    2011-05-01

    A CO{sub 2} sequestration project is being considered to (1) capture CO{sub 2} emissions from the Consumers Cooperative Refineries Limited at Regina, Saskatchewan and (2) geologically sequester the captured CO{sub 2} locally in a deep saline aquifer. This project is a collaboration of several industrial and governmental organizations, including the Petroleum Technology Research Centre (PTRC), Sustainable Development Technology Canada (SDTC), SaskEnvironment Go Green Fund, SaskPower, CCRL, Schlumberger Carbon Services, and Enbridge. The project objective is to sequester 600 tonnes CO{sub 2}/day. Injection is planned to start in 2012 or 2013 for a period of 25 years for a total storage of approximately 5.5 million tonnes CO{sub 2}. This report presents an assessment of the leakage risk of the proposed project using a methodology known as the Certification Framework (CF). The CF is used for evaluating CO{sub 2} leakage risk associated with geologic carbon sequestration (GCS), as well as brine leakage risk owing to displacement and pressurization of brine by the injected CO{sub 2}. We follow the CF methodology by defining the entities (so-called Compartments) that could be impacted by CO{sub 2} leakage, the CO{sub 2} storage region, the potential for leakage along well and fault pathways, and the consequences of such leakage. An understanding of the likelihood and consequences of leakage forms the basis for understanding CO{sub 2} leakage risk, and forms the basis for recommendations of additional data collection and analysis to increase confidence in the risk assessment.

  3. Potential impact on air pollution from ambitious national CO2 emission abatement strategies in the Nordic countries – environmental links between the UNFCCC and the UNECE – CLRTAP

    International Nuclear Information System (INIS)

    Åström, Stefan; Tohka, Antti; Bak, Jesper; Lindblad, Maria; Arnell, Jenny

    2013-01-01

    This article presents results from a meta-study of Nordic low carbon dioxide (CO 2 ) emission scenarios. The focus of the study was to explore possible environmental impacts if selected Nordic low CO 2 emission scenarios were achieved by 2020. The impacts of concern were climate change, acidification, eutrophication and human health. Results from this study indicate that large scale reduction of CO 2 emissions by 2020 in a Nordic energy system requires large scale penetration of technical measures and structural changes. The environmental improvements achieved would most often facilitate achievement of air pollution targets as well as post-Kyoto targets for greenhouse gas (GHG) emissions. All scenarios do, however, not imply co-benefits between air pollution and CO 2 emission reductions and the net impact on climate change could be smaller than anticipated. A conclusion is that co-benefits and risks for trade-offs between air quality and climate change should be emphasised in the development of low-CO 2 energy and emission strategies. - Highlights: ► CO 2 abatement strategies differ in impact on environment, human health and climate. ► Bio fuel CO 2 strategies can imply smaller climate and environmental benefits. ► Nordic ‘clean’ electricity export can give environmental benefits if replacing coal.

  4. Shale-Gas Experience as an Analog for Potential Wellbore Integrity Issues in CO2 Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Carey, James W. [Los Alamos National Laboratory; Simpson, Wendy S. [Los Alamos National Laboratory; Ziock, Hans-Joachim [Los Alamos National Laboratory

    2011-01-01

    Shale-gas development in Pennsylvania since 2003 has resulted in about 19 documented cases of methane migration from the deep subsurface (7,0000) to drinking water aquifers, soils, domestic water wells, and buildings, including one explosion. In all documented cases, the methane leakage was due to inadequate wellbore integrity, possibly aggravated by hydrofracking. The leakage of methane is instructive on the potential for CO{sub 2} leakage from sequestration operations. Although there are important differences between the two systems, both involve migrating, buoyant gas with wells being a primary leakage pathway. The shale-gas experience demonstrates that gas migration from faulty wells can be rapid and can have significant impacts on water quality and human health and safety. Approximately 1.4% of the 2,200 wells drilled into Pennsylvania's Marcellus Formation for shale gas have been implicated in methane leakage. These have resulted in damage to over 30 domestic water supplies and have required significant remediation via well repair and homeowner compensation. The majority of the wellbore integrity problems are a result of over-pressurization of the wells, meaning that high-pressure gas has migrated into an improperly protected wellbore annulus. The pressurized gas leaks from the wellbore into the shallow subsurface, contaminating drinking water or entering structures. The effects are localized to a few thousands of feet to perhaps two-three miles. The degree of mixing between the drinking water and methane is sufficient that significant chemical impacts are created in terms of elevated Fe and Mn and the formation of black precipitates (metal sulfides) as well as effervescing in tap water. Thus it appears likely that leaking CO{sub 2} could also result in deteriorated water quality by a similar mixing process. The problems in Pennsylvania highlight the critical importance of obtaining background data on water quality as well as on problems associated with

  5. Simulation of a Potential CO2 Storage in the West Paris Basin: Site Characterization and Assessment of the Long-Term Hydrodynamical and Geochemical Impacts Induced by the CO2 Injection

    Directory of Open Access Journals (Sweden)

    Estublier Audrey

    2017-07-01

    Full Text Available This article presents the preliminary results of a study carried out as part of a demonstration project of CO2 storage in the Paris Basin. This project funded by ADEME (French Environment and Energy Management Agency and several industrial partners (TOTAL, ENGIE, EDF, Lafarge, Air Liquide, Vallourec aimed to study the possibility to set up an experimental infrastructure of CO2 transport and storage. Regarding the storage, the objectives were: (1 to characterize the selected site by optimizing the number of wells in a CO2 injection case of 200 Mt over 50 years in the Trias, (2 to simulate over time the CO2 migration and the induced pressure field, and (3 to analyze the geochemical behavior of the rock over the long term (1,000 years. The preliminary site characterization study revealed that only the southern area of Keuper succeeds to satisfy this injection criterion using only four injectors. However, a complementary study based on a refined fluid flow model with additional secondary faults concluded that this zone presents the highest potential of CO2 injection but without reaching the objective of 200 Mt with a reasonable number of wells. The simulation of the base scenario, carried out before the model refinement, showed that the overpressure above 0.1 MPa covers an area of 51,869 km2 in the Chaunoy formation, 1,000 years after the end of the injection, which corresponds to the whole West Paris Basin, whereas the CO2 plume extension remains small (524 km2. This overpressure causes brine flows at the domain boundaries and a local overpressure in the studied oil fields. Regarding the preliminary risk analysis of this project, the geochemical effects induced by the CO2 injection were studied by simulating the fluid-rock interactions with a coupled geochemical and fluid flow model in a domain limited to the storage complex. A one-way coupling of two models based on two domains fitting into each other was developed using dynamic boundary

  6. NHC-Ag/Pd-Catalyzed Reductive Carboxylation of Terminal Alkynes with CO2 and H2 : A Combined Experimental and Computational Study for Fine-Tuned Selectivity.

    Science.gov (United States)

    Yu, Dingyi; Zhou, Feng; Lim, Diane S W; Su, Haibin; Zhang, Yugen

    2017-03-09

    Reductive carboxylation of terminal alkynes utilizing CO 2 and H 2 as reactants is an interesting and challenging transformation. Theoretical calculations indicated it would be kinetically possible to obtain cinnamic acid, the reductive carboxylation product, from phenylacetylene in a CO 2 /H 2 system with an N-heterocyclic carbene (NHC)-supported Ag/Pd bimetallic catalysts through competitive carboxylation/hydrogenation cascade reactions in one step. These calculations were verified experimentally with a poly-NHC-supported Ag/Pd catalyst. By tuning the catalyst composition and reaction temperature, phenylacetylene was selectively converted to cinnamic acid, hydrocinnamic acid, or phenylpropiolic acid in excellent yields. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. CO2 reduction in the Danish transportation sector. Working paper 10: Energy efficiency of the private cars - a package of control measures

    International Nuclear Information System (INIS)

    1997-03-01

    Average requirements to automotive fuel efficiency in new cars and differentiation of registration and weight taxes according to fuel consumption by a car result in fewer new cars due to very high registration tax and lower driving costs per km, which is against the CO 2 reduction measure. More efficient car manufacturing would eventually lead to a lower registration tax. Higher tax on fuels is another solution to the problem. (EG)

  8. A Hierarchical Z-Scheme α-Fe2 O3 /g-C3 N4 Hybrid for Enhanced Photocatalytic CO2 Reduction.

    Science.gov (United States)

    Jiang, Zhifeng; Wan, Weiming; Li, Huaming; Yuan, Shouqi; Zhao, Huijun; Wong, Po Keung

    2018-03-01

    The challenge in the artificial photosynthesis of fossil resources from CO 2 by utilizing solar energy is to achieve stable photocatalysts with effective CO 2 adsorption capacity and high charge-separation efficiency. A hierarchical direct Z-scheme system consisting of urchin-like hematite and carbon nitride provides an enhanced photocatalytic activity of reduction of CO 2 to CO, yielding a CO evolution rate of 27.2 µmol g -1 h -1 without cocatalyst and sacrifice reagent, which is >2.2 times higher than that produced by g-C 3 N 4 alone (10.3 µmol g -1 h -1 ). The enhanced photocatalytic activity of the Z-scheme hybrid material can be ascribed to its unique characteristics to accelerate the reduction process, including: (i) 3D hierarchical structure of urchin-like hematite and preferable basic sites which promotes the CO 2 adsorption, and (ii) the unique Z-scheme feature efficiently promotes the separation of the electron-hole pairs and enhances the reducibility of electrons in the conduction band of the g-C 3 N 4 . The origin of such an obvious advantage of the hierarchical Z-scheme is not only explained based on the experimental data but also investigated by modeling CO 2 adsorption and CO adsorption on the three different atomic-scale surfaces via density functional theory calculation. The study creates new opportunities for hierarchical hematite and other metal-oxide-based Z-scheme system for solar fuel generation. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Growth, reproductive phenology and yield responses of a potential biofuel plant, Jatropha curcas grown under projected 2050 levels of elevated CO2.

    Science.gov (United States)

    Kumar, Sumit; Chaitanya, Bharatula S K; Ghatty, Sreenivas; Reddy, Attipalli R

    2014-11-01

    Jatropha (Jatropha curcas) is a non-edible oil producing plant which is being advocated as an alternative biofuel energy resource. Its ability to grow in diverse soil conditions and minimal requirements of essential agronomical inputs compared with other oilseed crops makes it viable for cost-effective advanced biofuel production. We designed a study to investigate the effects of elevated carbon dioxide concentration ([CO(2)]) (550 ppm) on the growth, reproductive development, source-sink relationships, fruit and seed yield of J. curcas. We report, for the first time that elevated CO(2) significantly influences reproductive characteristics of Jatropha and improve its fruit and seed yields. Net photosynthetic rate of Jatropha was 50% higher in plants grown in elevated CO(2) compared with field and ambient CO(2) -grown plants. The study also revealed that elevated CO(2) atmosphere significantly increased female to male flower ratio, above ground biomass and carbon sequestration potential in Jatropha (24 kg carbon per tree) after 1 year. Our data demonstrate that J. curcas was able to sustain enhanced rate of photosynthesis in elevated CO(2) conditions as it had sufficient sink strength to balance the increased biomass yields. Our study also elucidates that the economically important traits including fruit and seed yield in elevated CO(2) conditions were significantly high in J. curcas that holds great promise as a potential biofuel tree species for the future high CO(2) world. © 2014 Scandinavian Plant Physiology Society.

  10. Self-assembled hierarchical direct Z-scheme g-C3N4/ZnO microspheres with enhanced photocatalytic CO2 reduction performance

    Science.gov (United States)

    Nie, Ning; Zhang, Liuyang; Fu, Junwei; Cheng, Bei; Yu, Jiaguo

    2018-05-01

    Photocatalytic reduction of CO2 into hydrocarbon fuels has been regarded as a promising approach to ease the greenhouse effect and the energy shortage. Herein, an electrostatic self-assembly method was exploited to prepare g-C3N4/ZnO composite microsphere. This method simply utilized the opposite surface charge of each component, achieving a hierarchical structure with intimate contact between them. A much improved photocatalytic CO2 reduction activity was attained. The CH3OH production rate was 1.32 μmol h-1 g-1, which was 2.1 and 4.1 times more than that of the pristine ZnO and g-C3N4, respectively. This facile design bestowed the g-C3N4/ZnO composite an extended light adsorption caused by multi-light scattering effect. It also guaranteed the uniform distribution of g-C3N4 nanosheets on the surface of ZnO microspheres, maximizing their advantage and synergistic effect. Most importantly, the preeminent performance was proposed and validated based on the direct Z-scheme. The recombination rate was considerably suppressed. This work features the meliority of constructing hierarchical direct Z-scheme structures in photocatalytic CO2 reduction reactions.

  11. Actions conducted in Switzerland for energy conservation and CO2 emission reduction, particularly in the transport sector

    International Nuclear Information System (INIS)

    Cattin, J.

    1991-01-01

    The aim of Switzerland is to stabilize the CO 2 emissions by year 2000 and to reduce them from 20 pc by 2005 and from 50 pc by 2025. In order to attain these objectives, several measures should be taken: in the residential sector, the heating appliances (space heating and hot water production) should be efficiency-enhanced and an individual counting system should be used; energy audits should be enforced in industry; in the transportation sector, railway transportation should be enhanced and a pollution tax on automobile fuel should be applied

  12. A highly selective copper-indium bimetallic electrocatalyst for the electrochemical reduction of aqueous CO2to CO

    KAUST Repository

    Rasul, Shahid; Anjum, Dalaver H.; Jedidi, Abdesslem; Minenkov, Yury; Cavallo, Luigi; Takanabe, Kazuhiro

    2014-01-01

    The challenge in the electrochemical reduction of aqueous carbon dioxide is in designing a highly selective, energy-efficient, and non-precious-metal electrocatalyst that minimizes the competitive reduction of proton to form hydrogen during aqueous

  13. CO2 Capture and Reuse

    International Nuclear Information System (INIS)

    Thambimuthu, K.; Gupta, M.; Davison, J.

    2003-01-01

    CO2 capture and storage including its utilization or reuse presents an opportunity to achieve deep reductions in greenhouse gas emissions from fossil energy use. The development and deployment of this option could significantly assist in meeting a future goal of achieving stabilization of the presently rising atmospheric concentration of greenhouse gases. CO2 capture from process streams is an established concept that has achieved industrial practice. Examples of current applications include the use of primarily, solvent based capture technologies for the recovery of pure CO2 streams for chemical synthesis, for utilization as a food additive, for use as a miscible agent in enhanced oil recovery operations and removal of CO2 as an undesired contaminant from gaseous process streams for the production of fuel gases such as hydrogen and methane. In these applications, the technologies deployed for CO2 capture have focused on gas separation from high purity, high pressure streams and in reducing (or oxygen deficient) environments, where the energy penalties and cost for capture are moderately low. However, application of the same capture technologies for large scale abatement of greenhouse gas emissions from fossil fuel use poses significant challenges in achieving (at comparably low energy penalty and cost) gas separation in large volume, dilute concentration and/or low pressure flue gas streams. This paper will focus on a review of existing commercial methods of CO2 capture and the technology stretch, process integration and energy system pathways needed for their large scale deployment in fossil fueled processes. The assessment of potential capture technologies for the latter purpose will also be based on published literature data that are both 'transparent' and 'systematic' in their evaluation of the overall cost and energy penalties of CO2 capture. In view of the of the fact that many of the existing commercial processes for CO2 capture have seen applications in

  14. Extra training in greenhouse effect? Identification of starting points for intervention strategies aimed at CO2 reduction in school buildings; Bijscholen in broeikaseffect? Identificatie van aangrijpingspunten voor interventiestrategieen gericht op CO2-reductie in schoolgebouwen

    Energy Technology Data Exchange (ETDEWEB)

    Blaauw, K.; Groot, M.

    2003-07-01

    A survey was held among 550 Dutch institutes for primary, secondary, vocational and adult education to determine and analyze the decisive factors for energy conservation and CO2 reduction in school buildings in the Netherlands. [Dutch] In opdracht van Novem heeft CE een studie verricht naar aangrijpingspunten voor interventiestrategieen gericht op energiebesparing in schoolgebouwen. Aan de hand van een literatuurstudie, verschillende kwalitatieve interviews is als eerste getracht inzicht te verkrijgen in de kwaliteit van het gebouwenvoorraad en het energieverbruik in gebouwen. Het blijkt dat ruim 50% van de voorraad in de PO en VO sector voor 1975 is gebouwd, waarbij weinig besparende bouwmaatregelen zijn getroffen en binnen circa 5 a 15 jaar wordt vervangen door nieuwbouw of grootschalig gerenoveerd wordt. In de BVE sector is op korte termijn veel nieuwbouw te verwachten. Vervolgens is aan de hand van een schriftelijke enquete onder 550 instellingen in het primair, voortgezet en beroeps- en volwassenenonderwijs bepaald wat de determinanten zijn van CO2 reductie door gebouw en procesmaatregelen. Op basis van 236 geretourneerde enquetes zijn de volgende conclusies te trekken: De grote variatie binnen de VO sector in professionaliteit, wijze van besluitvorming en de rollen van de verschillende actoren maakt het moeilijk eenduidige aangrijpingspunten te identificeren. De scholen zelf geven subsidieregelingen als verreweg de belangrijkste mogelijkheid om energiebesparing op scholen te stimuleren. Dat is niet verwonderlijk gezien het beperkte budget van scholen in het algemeen en met name voor dergelijke activiteiten. Het energiebedrijf wordt door de meeste scholen het belangrijkst gevonden voor informatie over energiebesparing gevolgd door externe adviseurs bij met name grotere scholen. De scholen gaven verder een grote voorkeur aan voor persoonlijke advisering boven andere vormen van informatievoorziening.

  15. Two-component, ab initio potential energy surface for CO2—H2O, extension to the hydrate clathrate, CO2@(H2O)20, and VSCF/VCI vibrational analyses of both

    Science.gov (United States)

    Wang, Qingfeng Kee; Bowman, Joel M.

    2017-10-01

    We report an ab initio, full-dimensional, potential energy surface (PES) for CO2—H2O, in which two-body interaction energies are fit using a basis of permutationally invariant polynomials and combined with accurate potentials for the non-interacting monomers. This approach which we have termed "plug and play" is extended here to improve the precision of the 2-body fit in the long range. This is done by combining two separate fits. One is a fit to 47 593 2-body energies in the region of strong interaction and approaching the long range, and the second one is a fit to 6244 2-body energies in the long range. The two fits have a region of overlap which permits a smooth switch from one to the other. All energies are obtained at the CCSD(T)-F12b/aug-cc-pVTZ level of theory. Properties of the full PES, i.e., stationary points, harmonic frequencies of the global minimum, etc., are shown to be in excellent agreement with direct CCSD(T)-F12b/aug-cc-pVTZ results. Diffusion Monte Carlo calculations of the dimer zero-point energy (ZPE) are performed, and a dissociation energy, D0, of 787 cm-1 is obtained using that ZPE, De, and the rigorous ZPEs of the monomers. Using a benchmark De, D0 is 758 cm-1. Vibrational self-consistent field (VSCF)/virtual state configuration interaction (VCI) MULTIMODE calculations of intramolecular fundamentals are reported and are in good agreement with available experimental results. Finally, the full dimer PES is combined with an existing ab initio water potential to develop a potential for the CO2 hydrate clathrate CO2(H2O)20(512 water cage). A full normal-mode analysis of this hydrate clathrate is reported as are local-monomer VSCF/VCI calculations of the fundamentals of CO2.

  16. Two-component, ab initio potential energy surface for CO2-H2O, extension to the hydrate clathrate, CO2@(H2O)20, and VSCF/VCI vibrational analyses of both.

    Science.gov (United States)

    Wang, Qingfeng Kee; Bowman, Joel M

    2017-10-28

    We report an ab initio, full-dimensional, potential energy surface (PES) for CO 2 -H 2 O, in which two-body interaction energies are fit using a basis of permutationally invariant polynomials and combined with accurate potentials for the non-interacting monomers. This approach which we have termed "plug and play" is extended here to improve the precision of the 2-body fit in the long range. This is done by combining two separate fits. One is a fit to 47 593 2-body energies in the region of strong interaction and approaching the long range, and the second one is a fit to 6244 2-body energies in the long range. The two fits have a region of overlap which permits a smooth switch from one to the other. All energies are obtained at the CCSD(T)-F12b/aug-cc-pVTZ level of theory. Properties of the full PES, i.e., stationary points, harmonic frequencies of the global minimum, etc., are shown to be in excellent agreement with direct CCSD(T)-F12b/aug-cc-pVTZ results. Diffusion Monte Carlo calculations of the dimer zero-point energy (ZPE) are performed, and a dissociation energy, D 0 , of 787 cm -1 is obtained using that ZPE, D e , and the rigorous ZPEs of the monomers. Using a benchmark D e , D 0 is 758 cm -1 . Vibrational self-consistent field (VSCF)/virtual state configuration interaction (VCI) MULTIMODE calculations of intramolecular fundamentals are reported and are in good agreement with available experimental results. Finally, the full dimer PES is combined with an existing ab initio water potential to develop a potential for the CO 2 hydrate clathrate CO 2 (H 2 O) 20 (5 12 water cage). A full normal-mode analysis of this hydrate clathrate is reported as are local-monomer VSCF/VCI calculations of the fundamentals of CO 2 .

  17. On the potential of the 2041–2047 nm spectral region for remote sensing of atmospheric CO2 isotopologues

    International Nuclear Information System (INIS)

    Reuter, M.; Bovensmann, H.; Buchwitz, M.; Burrows, J.P.; Deutscher, N.M.; Heymann, J.; Rozanov, A.; Schneising, O.; Suto, H.; Toon, G.C.; Warneke, T.

    2012-01-01

    Pressing open questions about the carbon cycle can be addressed with precise measurements of the three most abundant CO 2 isotopologues 16 O 12 C 16 O, 16 O 13 C 16 O, and 16 O 12 C 18 O. Such measurements can, e.g., help to further constrain oceanic and biospheric net fluxes or to differentiate between the gross biospheric fluxes photosynthesis and respiration. The 2041–2047nm (about 4885–4900cm −1 ) spectral region contains separated absorption lines of the three most abundant CO 2 isotopologues. Their spectral properties make this spectral region well suited for the use of a light path proxy method for the retrieval of δ 13 C and δ 18 O (the ratio of heavier to lighter isotopologues relative to a standard). An optimal estimation based light path proxy retrieval for δ 13 C and δ 18 O has been set up, applicable to GOSAT (Greenhouse gases Observing Satellite) and ground-based FTS (Fourier transform spectrometer) measurements. Initial results show that it is possible to retrieve δ 13 C and δ 18 O from ground-based FTS instruments with a precision of 0.6–1.6‰ and from GOSAT with a precision of about 30‰. Comparison of the achievable precision with the expected atmospheric signals shows that ground-based FTS remote sensing measurements have the potential to gain valuable information on δ 13 C and δ 18 O if averaging a sufficient number of measurements. It seems unlikely that this applies also to GOSAT because of the lower precision and a conceptual larger sensitivity to scattering related errors in satellite viewing geometry. -- Highlights: ► The 2041–2047 nm region is suited for remote sensing atmospheric CO 2 isotopologues. ► A δ 13 C and δ 18 O retrieval was set up for ground-based FTS and the GOSAT satellite. ► The retrieval precision of δ 13 C and δ 18 O is about 0.6–1.6‰ (FTS) and 30‰ (GOSAT). ► FTS measurements can give valuable information on atmospheric δ 13 C and δ 18 O.

  18. Amorphizing of Cu Nanoparticles toward Highly Efficient and Robust Electrocatalyst for CO2 Reduction to Liquid Fuels with High Faradaic Efficiencies.

    Science.gov (United States)

    Duan, Yan-Xin; Meng, Fan-Lu; Liu, Kai-Hua; Yi, Sha-Sha; Li, Si-Jia; Yan, Jun-Min; Jiang, Qing

    2018-04-01

    Conversion of carbon dioxide (CO 2 ) into valuable chemicals, especially liquid fuels, through electrochemical reduction driven by sustainable energy sources, is a promising way to get rid of dependence on fossil fuels, wherein developing of highly efficient catalyst is still of paramount importance. In this study, as a proof-of-concept experiment, first a facile while very effective protocol is proposed to synthesize amorphous Cu NPs. Unexpectedly, superior electrochemical performances, including high catalytic activity and selectivity of CO 2 reduction to liquid fuels are achieved, that is, a total Faradaic efficiency of liquid fuels can sum up to the maximum value of 59% at -1.4 V, with formic acid (HCOOH) and ethanol (C 2 H 6 O) account for 37% and 22%, respectively, as well as a desirable long-term stability even up to 12 h. More importantly, this work opens a new avenue for improved electroreduction of CO 2 based on amorphous metal catalysts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Enhanced Photocatalytic Reduction of CO2 to CO through TiO2 Passivation of InP in Ionic Liquids.

    Science.gov (United States)

    Zeng, Guangtong; Qiu, Jing; Hou, Bingya; Shi, Haotian; Lin, Yongjing; Hettick, Mark; Javey, Ali; Cronin, Stephen B

    2015-09-21

    A robust and reliable method for improving the photocatalytic performance of InP, which is one of the best known materials for solar photoconversion (i.e., solar cells). In this article, we report substantial improvements (up to 18×) in the photocatalytic yields for CO2 reduction to CO through the surface passivation of InP with TiO2 deposited by atomic layer deposition (ALD). Here, the main mechanisms of enhancement are the introduction of catalytically active sites and the formation of a pn-junction. Photoelectrochemical reactions were carried out in a nonaqueous solution consisting of ionic liquid, 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM]BF4), dissolved in acetonitrile, which enables CO2 reduction with a Faradaic efficiency of 99% at an underpotential of +0.78 V. While the photocatalytic yield increases with the addition of the TiO2 layer, a corresponding drop in the photoluminescence intensity indicates the presence of catalytically active sites, which cause an increase in the electron-hole pair recombination rate. NMR spectra show that the [EMIM](+) ions in solution form an intermediate complex with CO2(-), thus lowering the energy barrier of this reaction. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Photoelectrocatalytic reduction of CO2 into chemicals using Pt-modified reduced graphene oxide combined with Pt-modified TiO2 nanotubes.

    Science.gov (United States)

    Cheng, Jun; Zhang, Meng; Wu, Gai; Wang, Xin; Zhou, Junhu; Cen, Kefa

    2014-06-17

    The photoelectrocatalytic (PEC) reduction of CO2 into high-value chemicals is beneficial in alleviating global warming and advancing a low-carbon economy. In this work, Pt-modified reduced graphene oxide (Pt-RGO) and Pt-modified TiO2 nanotubes (Pt-TNT) were combined as cathode and photoanode catalysts, respectively, to form a PEC reactor for converting CO2 into valuable chemicals. XRD, XPS, TEM, AFM, and SEM were employed to characterize the microstructures of the Pt-RGO and Pt-TNT catalysts. Reduction products, such as C2H5OH and CH3COOH, were obtained from CO2 under band gap illumination and biased voltage. A combined liquid product generation rate (CH3OH, C2H5OH, HCOOH, and CH3COOH) of approximately 600 nmol/(h·cm(2)) was observed. Carbon atom conversion rate reached 1,130 nmol/(h·cm(2)), which were much higher than those achieved using Pt-modified carbon nanotubes and platinum carbon as cathode catalysts.

  1. Evasion of CO2 injected into the ocean in the context of CO2 stabilization

    International Nuclear Information System (INIS)

    Kheshgi, Haroon S.

    2004-01-01

    The eventual evasion of injected CO 2 to the atmosphere is one consideration when assessing deep-sea disposal of CO 2 as a potential response option to climate change concerns. Evasion estimated using an ocean carbon cycle model is compared to long-term trajectories for future CO 2 emissions, including illustrative cases leading to stabilization of CO 2 concentration at various levels. Modeled residence time for CO 2 injected into the deep ocean exceeds the 100-year time-scale usually considered in scenarios for future emissions, and the potential impacts of climate change. Illustrative cases leading monotonically to constant CO 2 concentration have been highlighted by the Intergovernmental Panel on Climate Change to give guidance on possible timing of emission reductions that may be required to stabilize greenhouse gas concentrations at various levels. For stabilization cases considered, significant modeled evasion does not occur until long after CO 2 emissions have reached a maximum and begun to decline. Illustrative cases can also lead to a maximum in CO 2 concentration followed by a decline to slowly decreasing concentrations. In such cases, future injection of emissions into the deep ocean leads to lower maximum CO 2 concentration, with less effect on concentration later on in time

  2. Reduction of CO2 emission from transportation activities in the area of Pasar Besar in Malang City

    Science.gov (United States)

    Sari, K. E.; Sulistyo, D. E.; Utomo, D. M.

    2017-06-01

    The number of vehicles increases every year. Where vehicles are the largest contributor to air pollution up to 70%-80%, while 20%-30% caused by industrial activities. The increasing number of vehicles which perform movements will result in more emissions of vehicles in the free air of the city. Traffic is also influenced by the presence of land use. One of the types of land use that have considerable influence against the movement of traffic is trade. Along with the development of transport activities in the area of Pasar Besar Malang city (the Biggest Traditional Market in Malang), it will cause problems such as traffic jam and air pollution. Therefore, the need for proper handling of the problem of traffic jam and air pollution in the area of Pasar Besar that is to identify the performance of road traffic around area of Pasar Besar and calculate the quantity of CO2 emissions based on the footprint of transport on the area of Pasar Besar. Where is produced that level of service roads on its way around area of Pasar Besar have an average value between LOS A and B, while the quantity of CO2 emissions is based on the footprint of transport on area of Pasar Besar that is amounting to 4,551.42 tons/year. The magnitude of the emissions have exceeded the standard of composition in the air so that the need for recommendations. Recommendations in this research is in the form of simulated users of private vehicle redirects to public transportation based on the level of willingness to switch by the users of private vehicles. The selected simulation that is the second of four simulations with the output of emissions amounting to 3,952.91 tons/year in which can reduce emissions amounting to 598.51 tons/year or approximately 13.15%.

  3. On the potential for a CO2 fertilization effect in forest trees: An assessment of 58 controlled-exposure studies and estimates of the biotic growth factor

    International Nuclear Information System (INIS)

    Wullschleger, S.D.; Post, W.M.; King, A.W.

    1992-01-01

    Characterizing the response of terrestrial ecosystems to increasing concentrations of atmospheric CO 2 and estimating their biological capacity to either moderate or accelerate predicted changes in the earth's climate, continues to present a formidable challenge to experimentalist and modelers alike. Nevertheless, it is generally recognized that the carbon dynamics of terrestrial vegetation represent an important biospheric feedback to increasing CO 2 concentrations, and hence to global warming, and as such there exists little debate that ecosystems occupy a.potentially pivotal role in determining both the direction and rate of future changes in atmospheric CO 2 concentration. What is currently the subject of much debate, however, is whether terrestrial ecosystems will contribute to global warming by releasing additional CO 2 the atmosphere as a result of increasing respiration and/or decomposition in a warming climate, or whether they will instead sequester additional carbon in response to the enhancing effects of atmospheric CO 2 on plant growth. This latter response, the so-called CO 2 fertilization effect, has been hypothesized as an important negative feedback to global warming, offering the potential to constrain future increases in atmospheric CO 2 concentration, and has often been invoked to either partially or wholly account for the estimated 1.6 Gt C/year imbalance or ''missing sink'' in calculations of the global carbon budget

  4. Report of fiscal 1999 basic survey for joint implementation, etc. Feasibility study on energy conservation and reduction of CO2 emission at Omsk Refinery

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    This paper explains fiscal 1999 survey on energy conservation and reduction of CO2 at Omsk Refinery in the Russian Federation for the purpose of making the project tied to the COP3 joint implementation. This refinery is the largest class refinery in Russia having a capacity of 600,000 BPSD. The atmospheric distillation unit AVT-10, which emits 470,000 t-CO2/year, was selected for the object of the survey. As the modification plans, optimization of process system, modification of waste heat boiler and installation of new furnaces were considered. The plans 1, 2 are possible due to their low investment costs. The plan 3 to install new furnaces is able to reduce the large volume of CO2 emission though its investment cost is higher. For each modification plan, estimation was made for the investment cost, the benefit by energy saving and the volume of reduction of CO2 emission. The results for each of the plans 1, 2 and 3 were 907x10{sup 3}, 3,377x10{sup 3}, 50,400x10{sup 3} in US$; 535x10{sup 3}, 928x10{sup 3}, 1,407x10{sup 3} in US$; and 36.1x10{sup 3}, 68.2x10{sup 3}, 86.6x10{sup 3} tons/year. The Russian side showed their satisfaction of the results and keen interest in the energy saving effect. For the purpose of realizing this plan, financial assistance and technological cooperation are essential. Russia shows their great expectations for the Japanese government. (NEDO)

  5. The potential reduction of household space heating CO2 emissions in the Netherlands

    NARCIS (Netherlands)

    Engelmoer, Wiebe

    2011-01-01

    SUMMARY Space heating is responsible for more than half of the total Dutch household energy demand, a large share is based on natural gas. With increasing concern about global warming and depleting gas reserves, energy saving has become an important topi

  6. Potential improvements of supercritical recompression CO2 Brayton cycle by mixing other gases for power conversion system of a SFR

    International Nuclear Information System (INIS)

    Jeong, Woo Seok; Lee, Jeong Ik; Jeong, Yong Hoon

    2011-01-01

    Highlights: → S-CO 2 cycle could be enhanced by shifting the critical point of working fluids using gas mixture. → In-house cycle code was developed to analyze supercritical Brayton cycles with gas mixture. → Gas mixture candidates were selected through a screening process: CO 2 mixing with N 2 , O 2 , He, and Ar. → CO 2 -He binary mixture shows the highest cycle efficiency increase. → Lowering the critical temperature and critical pressure of the coolant has a positive effect on the total cycle efficiency. - Abstract: A sodium-cooled fast reactor (SFR) is one of the strongest candidates for the next generation nuclear reactor. However, the conventional design of a SFR concept with an indirect Rankine cycle is subjected to a possible sodium-water reaction. To prevent any hazards from sodium-water reaction, a SFR with the Brayton cycle using Supercritical Carbon dioxide (S-CO 2 ) as the working fluid can be an alternative approach to improve the current SFR design. However, the S-CO 2 Brayton cycle is more sensitive to the critical point of working fluids than other Brayton cycles. This is because compressor work is significantly decreased slightly above the critical point due to high density of CO 2 near the boundary between the supercritical state and the subcritical state. For this reason, the minimum temperature and pressure of cycle are just above the CO 2 critical point. In other words, the critical point acts as a limitation of the lowest operating condition of the cycle. In general, lowering the rejection temperature of a thermodynamic cycle can increase the efficiency. Therefore, changing the critical point of CO 2 can result in an improvement of the total cycle efficiency with the same cycle layout. A small amount of other gases can be added in order to change the critical point of CO 2 . The direction and range of the critical point variation of CO 2 depends on the mixed component and its amount. Several gases that show chemical stability with

  7. Estimation of CO2 reduction by parallel hard-type power hybridization for gasoline and diesel vehicles.

    Science.gov (United States)

    Oh, Yunjung; Park, Junhong; Lee, Jong Tae; Seo, Jigu; Park, Sungwook

    2017-10-01

    The purpose of this study is to investigate possible improvements in ICEVs by implementing fuzzy logic-based parallel hard-type power hybrid systems. Two types of conventional ICEVs (gasoline and diesel) and two types of HEVs (gasoline-electric, diesel electric) were generated using vehicle and powertrain simulation tools and a Matlab-Simulink application programming interface. For gasoline and gasoline-electric HEV vehicles, the prediction accuracy for four types of LDV models was validated by conducting comparative analysis with the chassis dynamometer and OBD test data. The predicted results show strong correlation with the test data. The operating points of internal combustion engines and electric motors are well controlled in the high efficiency region and battery SOC was well controlled within ±1.6%. However, for diesel vehicles, we generated virtual diesel-electric HEV vehicle because there is no available vehicles with similar engine and vehicle specifications with ICE vehicle. Using a fuzzy logic-based parallel hybrid system in conventional ICEVs demonstrated that HEVs showed superior performance in terms of fuel consumption and CO 2 emission in most driving modes. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. The cost of CO2 reduction. An application of the Global 2100 Model to Germany and France

    International Nuclear Information System (INIS)

    Pfaffenberger, W.

    1992-01-01

    This paper reports on an application of the global 2100 model to Germany and France. The model is a five region world model which allows to simulate economic growth scenarios under different restrictions regarding the output of CO 2 . The basic production factors are capital plus labour and energy. Energy consists of electric and non-electric energy production. Electric energy is described in terms of different production technics whereas non-electric energy is described in terms of different resources. Energy and capital plus labour are substitutes as within each factor are capital and labour and electric and non-electric energy. Decision on the allocation of factors of production is made on the basis of prices: - endogeneous prices determined within the model and within a region, - exogeneous prices which are set by the user of the model and, - prices that are exogeneous to a region but internationally endogeneous. Exogeneous prices are set for coal and coal based technologies, renewable energies and advanced technologies of electricity production. The price of oil is internationally endogeneous in a certain way: by trial and error the international oil price has to be set in such a way that oil trade between exporting and importing countries will be balanced. Within the time horizon of the model a technological shift between fossil and non-fossil energy resources is possible. 1 ref., 4 figs., 2 tabs

  9. Predicting the ultimate potential of natural gas SOFC power cycles with CO2 capture - Part B: Applications

    Science.gov (United States)

    Campanari, Stefano; Mastropasqua, Luca; Gazzani, Matteo; Chiesa, Paolo; Romano, Matteo C.

    2016-09-01

    An important advantage of solid oxide fuel cells (SOFC) as future systems for large scale power generation is the possibility of being efficiently integrated with processes for CO2 capture. Focusing on natural gas power generation, Part A of this work assessed the performances of advanced pressurised and atmospheric plant configurations (SOFC + GT and SOFC + ST, with fuel cell integration within a gas turbine or a steam turbine cycle) without CO2 separation. This Part B paper investigates such kind of power cycles when applied to CO2 capture, proposing two ultra-high efficiency plant configurations based on advanced intermediate-temperature SOFCs with internal reforming and low temperature CO2 separation process. The power plants are simulated at the 100 MW scale with a set of realistic assumptions about FC performances, main components and auxiliaries, and show the capability of exceeding 70% LHV efficiency with high CO2 capture (above 80%) and a low specific primary energy consumption for the CO2 avoided (1.1-2.4 MJ kg-1). Detailed results are presented in terms of energy and material balances, and a sensitivity analysis of plant performance is developed vs. FC voltage and fuel utilisation to investigate possible long-term improvements. Options for further improvement of the CO2 capture efficiency are also addressed.

  10. Stable carbon isotope fractionation of organic cyst-forming dinoflagellates: Evaluating the potential for a CO2 proxy

    Science.gov (United States)

    Hoins, Mirja; Van de Waal, Dedmer B.; Eberlein, Tim; Reichart, Gert-Jan; Rost, Björn; Sluijs, Appy

    2015-07-01

    Over the past decades, significant progress has been made regarding the quantification and mechanistic understanding of stable carbon isotope fractionation (13C fractionation) in photosynthetic unicellular organisms in response to changes in the partial pressure of atmospheric CO2 (pCO2). However, hardly any data is available for organic cyst-forming dinoflagellates while this is an ecologically important group with a unique fossil record. We performed dilute batch experiments with four harmful dinoflagellate species known for their ability to form organic cysts: Alexandrium tamarense, Scrippsiella trochoidea, Gonyaulax spinifera and Protoceratium reticulatum. Cells were grown at a range of dissolved CO2 concentrations characterizing past, modern and projected future values (∼5-50 μmol L-1), representing atmospheric pCO2 of 180, 380, 800 and 1200 μatm. In all tested species, 13C fractionation depends on CO2 with a slope of up to 0.17‰ (μmol L)-1. Even more consistent correlations were found between 13C fractionation and the combined effects of particulate organic carbon quota (POC quota; pg C cell-1) and CO2. Carbon isotope fractionation as well as its response to CO2 is species-specific. These results may be interpreted as a first step towards a proxy for past pCO2 based on carbon isotope ratios of fossil organic dinoflagellate cysts. However, additional culture experiments focusing on environmental variables other than pCO2, physiological underpinning of the recorded response, testing for possible offsets in 13C values between cells and cysts, as well as field calibration studies are required to establish a reliable proxy.

  11. Topotactic reductive synthesis of A-site cation-ordered perovskite YBaCo2O x (x = 4.5-5.5) epitaxial thin films

    Science.gov (United States)

    Katayama, Tsukasa; Chikamatsu, Akira; Fukumura, Tomoteru; Hasegawa, Tetsuya

    2016-04-01

    A-site cation-ordered perovskite YBaCo2O x epitaxial films were synthesized by combining pulsed-laser deposition and topotactic reduction using CaH2. The oxygen contents (x) of the films could be controlled in a range of 4.5-5.5 by adjusting the reaction temperature. The c-axis length of the YBaCo2O x films decreased with decreasing x when x ≥ 5.3 but drastically increased when x ˜ 4.5. In contrast, the in-plane lattice constants remained locked-in by the substrate after the reaction. The metal insulator transition observed in bulk YBaCo2O5.5 was substantially suppressed in the present film, likely because of the epitaxial stra