a review climate change and carbon capture

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Page 1: A review climate change and carbon capture

Disclaimer: This document is based on information obtained from sources believed to be reliable but which have not been independently verified; there is no guarantee, representation or warranty and the author or distributor accept no responsibility or liability as to its accuracy or completeness. Expressions of opinion are those of the author only and are subject to change without notice without any warranty, liability or guarantee for the current relevance, correctness or completeness of any information provided within this Report. Furthermore, the author assumes no liability for any direct or indirect loss or damage or, in particular, for lost profit, which you may incur as a result of the use and existence of the information provided within this Report.

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As the source of two-thirds of global greenhouse-gas emissions, the energy sector will be pivotal in determining whether or not climate change goals are achieved. Energy-related carbon-dioxide emissions rise by 20% to 37.2 Gt in the New Policies Scenario, leaving the world on track for a long-term average temperature increase of 3.6 °C. WORLD ENERGY OUTLOOK 2013 FACTSHEET; International Energy Agency

Background

Global CO2 - 2010

CO2 emissions grew 5.9% in 2010 to reach 9.1 Gt C (33.5 Gt CO2), as against a 1.4% decrease in CO2 emissions in 20091

Including land-use change and deforestation, emissions in 2010 reached 10.0 Gt C (36.8 Gt CO2)

As of 2009 developing countries now emit more than developed countries in terms of consumption, and China now emits more than the US in terms of consumption.

According to estimates from Earth Observatory NASA, 55 per cent of anthropogenic CO2 is absorbed by the bio-sphere and the balance 45 per cent is the additional annual loading into the atmosphere. Therefore if both direct emissions and impacts of land use change2 are considered that translates to 4.5 Giga tonnes of carbon or 16.5 Giga tonnes of CO2 as additional atmospheric load in the year.

1In 2009, humans released about 8.4 billion tons of carbon into the atmosphere by burning fossil

fuel according to earth observatory NASA 2 When we clear forests, we remove a dense growth of plants that had stored carbon in wood,

stems, and leaves—biomass. By removing a forest, we eliminate plants that would otherwise take carbon out of the atmosphere as they grow. We tend to replace the dense growth with crops or pasture, which store less carbon. We also expose soil that vents carbon from decayed plant matter into the atmosphere. Humans are currently emitting just under a billion tons of carbon into the atmosphere per year through land use changes. (http://earthobservatory.nasa.gov/)

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GHG and Climate Change

The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) states: it is a greater than a 90 percent certainty that emissions of heat-trapping gases from human activities have caused “most of the observed increase in globally averaged temperatures since the mid-20th century.”

Global Carbon Dioxide Emissions

Without human interference, the carbon in fossil fuels would leak slowly into the atmosphere through volcanic activity over millions of years in the slow carbon cycle. By burning coal, oil, and natural gas, we accelerate the process, releasing vast amounts of carbon (carbon that took millions of years to accumulate) into the atmosphere every year. By doing so, we move the carbon from the slow cycle to the fast cycle. In 2009, humans released about 8.4 billion tons of carbon into the atmosphere by burning fossil fuel.

CO2 Concentrations and Global Temperature Anomalies

Since the beginning of the Industrial Revolution, when people first started burning fossil fuels, carbon dioxide concentrations in the atmosphere have risen from about 280 parts per million to 387 parts per million, a 39 percent increase. In 2013, this year, the carbon dioxide concentrations in the atmosphere crossed 400 parts per million—the highest concentration in two million years.

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The Greenhouse Effect

Because scientists know which wavelengths of energy each greenhouse gas absorbs, and the concentration of the gases in the atmosphere, they can calculate how much each gas contributes to warming the planet. Carbon dioxide causes about 20 percent of Earth’s greenhouse effect; water vapour accounts for about 50 percent; and clouds account for 25 percent. The rest is caused by small particles (aerosols) and minor greenhouse gases like methane. Water vapour concentrations in the air are controlled by Earth’s temperature. Warmer temperatures evaporate more water from the oceans, expand air masses, and lead to higher humidity. Cooling causes water vapour to condense and fall out as rain, sleet, or snow. Carbon dioxide, on the other hand, remains a gas at a wider range of atmospheric temperatures than water. Carbon dioxide molecules provide the initial greenhouse heating needed to maintain water vapour concentrations. When carbon dioxide concentrations drop, Earth cools, some water vapour falls out of the atmosphere, and the greenhouse warming caused by water vapour drops. Likewise, when carbon dioxide concentrations rise, air temperatures go up, and more water vapour evaporates into the atmosphere—which then amplifies greenhouse heating. So while carbon dioxide contributes less to the overall greenhouse effect than water vapour, scientists have established that carbon dioxide is the gas that sets the temperature. Carbon dioxide controls the amount of water vapour in the atmosphere and thus the size of the greenhouse effect.

Heat-trapping emissions (greenhouse gases) far outweigh the effects of other drivers acting on Earth’s climate. Source: Hansen et al. 2005, figure adapted by Union of Concerned Scientists.

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The Ocean and the Land - Fast Carbon Cycles

This diagram of the fast carbon cycle shows the movement of carbon between land, atmosphere, and oceans in billions of tons of carbon per year. Yellow numbers are natural fluxes; red are human contributions in billions of tons of carbon per year. White numbers indicate stored carbon. Atmospheric Carbon Dioxide and Global Temperature Anomaly

The Ocean Carbon Cycle About 22 percent of the carbon dioxide that people have put into the atmosphere has diffused into the ocean through the direct chemical exchange. Warmer oceans—a product of the greenhouse effect—could decrease the abundance of phytoplankton, which grow better in cool, nutrient-rich waters. This could limit the ocean’s ability to take carbon from the atmosphere through the fast carbon cycle. The Land Carbon Cycle Plants on land have taken up approximately 33 percent of the carbon dioxide that humans have put into the atmosphere. Carbon dioxide increases temperatures, extending the growing season and increasing humidity. Both factors have led to some additional plant growth. However, warmer temperatures and a longer growing season means plants need more water to survive. In the far north forests have already started to burn more, releasing carbon from the plants and the soil into the atmosphere. Also with less water, tropical trees slow their growth and take up less carbon, or die and release their stored carbon to the atmosphere. Warming caused by rising greenhouse gases is of particular concern in the far north, where frozen soil—permafrost—is thawing. Current research estimates that permafrost in the Northern Hemisphere holds 1,672 billion tons of organic carbon. If just 10 percent of this permafrost were to thaw, it could release enough extra carbon dioxide to the atmosphere to raise temperatures an additional 0.7 degrees Celsius (1.3 degrees Fahrenheit).

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Rising carbon dioxide concentrations are already causing the planet to heat up. At the same time that greenhouse gases have been increasing, average global temperatures have risen 0.8 degrees Celsius (1.4 degrees Fahrenheit) since 1880. Of this rise 0.6 degrees or 75 per cent has taken place since 1960. This rise in temperature isn’t all the warming we will see based on current carbon dioxide concentrations. Greenhouse warming doesn’t happen right away because the ocean soaks up heat. This means that Earth’s temperature will increase at least another 0.6 degrees Celsius (1 degree Fahrenheit) because of carbon dioxide already in the atmosphere. The degree to which temperatures go up beyond that depends in part on how much more carbon humans release into the atmosphere in the future

Beyond Global Warming: The Ozone Layer

This image is from a NASA satellite which tracks the hole in the ozone layer. Ozone protects the planet from the sun’s ultraviolet rays. Greenhouse gases destroy ozone. The ozone hole, however, is not a mechanism of global warming. Ultraviolet radiation represents less than one percent of the energy from the sun—not enough to be the cause of the excess heat from human activities. However, the EPA’s laboratory and epidemiological studies demonstrate that UVB (B-the medium range of ultraviolet radiation) causes nonmelanoma skin cancer and plays a major role in malignant melanoma development. In addition, UVB has been linked to cataracts -- a clouding of the eye’s lens. All sunlight contains some UVB, even with normal stratospheric ozone levels. Ozone layer depletion increases the amount of UVB and the risk of health effects. Physiological and developmental processes of plants are affected by UVB radiation, even by the amount of UVB in present-day sunlight. Despite mechanisms to reduce or repair these effects and a limited ability to adapt to increased levels of UVB, plant growth can be directly affected by UVB radiation.

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Indirect changes caused by UVB (such as changes in plant form, how nutrients are distributed within the plant, timing of developmental phases and secondary metabolism) may be equally, or sometimes more, important than damaging effects of UVB. These changes can have important implications for plant competitive balance, herbivory, plant diseases, and biogeochemical cycles.

Natural Temperature Anomalies

Source: IRI – The International Research Institute for Climate and Society El Niño/La Niña–Southern Oscillation is a band of anomalously warm ocean water temperatures that occasionally develops off the western coast of South America and can cause climatic changes across the Pacific Ocean. The 'Southern Oscillation' refers to variations in the temperature of the surface of the tropical eastern Pacific Ocean (warming and cooling known as El Niño and La Niña, respectively) and in air surface pressure in the tropical western Pacific. The two variations are coupled: the warm oceanic phase, El Niño, accompanies high air surface pressure in the western Pacific, while the cold phase, La Niña, accompanies low air surface pressure in the western Pacific. Mechanisms that cause the oscillation remain under study.

Sea surface temperature in the equatorial Pacific Ocean (above).

El Niño is characterized by unusually warm temperatures and La Niña by unusually cool temperatures in the equatorial Pacific.

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Anomalies (below) represent deviations from normal temperature values, with unusually warm temperatures shown in red and unusually cold anomalies shown in blue.

These phenomena are not well known outside the scientific community and the effects of these phenomena on overall global warming trends, such as the cooling-off in 2011, are often, mistakenly, presented as evidence that global warming is not actually a growing trend.

The ENSO (El Niño–Southern Oscillation or El Niño/La Niña–Southern Oscillation) as an overlay on the overall upward trend in global land-sea temperature.

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Today and Tomorrow

The UN estimates an average global temperature rise this century of four degrees. Any rise above two degrees will cause droughts in some parts of the world and floods in others. Extreme weather will displace populations and cause shortages of food and water. Ultimately, it will disrupt the lives of virtually everyone on the planet and many of the poorest countries in the world – those that have contributed least to the problem and benefitted least from the economic development that caused it – will suffer first and most severely. In a 2005 assessment, the World Health Organization (WHO) reported that human-induced changes in the Earth's climate now lead to at least 5 million cases of illness and more than 150,000 deaths every year. Temperature fluctuations may sway human health in a surprising number of ways, scientists have learned, from influencing the spread of infectious diseases to boosting the likelihood of illness-inducing heat waves and floods.

This map shows total CO2 emissions from fossil-fuel burning, cement production, and gas flaring for the world's countries in 2000. Emissions are expressed in million metric tons of carbon. The map was created by a team of climate and health scientists led by Jonathan Patz, associate professor of environmental studies and population health sciences at UW-Madison. Map courtesy the Centre for Sustainability and the Global Environment.

The health effects of global warming vary markedly at the regional scale. This map shows the estimated numbers of deaths per million people that could be attributed to global climate change in the year 2000. Drawing from data from the World Health Organization, the map was also created by Patz's team. Map courtesy the Centre for Sustainability and the Global Environment.

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Societal Response: Adaption and Prevention

Years of debate are yielding insufficient reductions in emissions to halt global warming. The focus now may well shift towards pragmatism; from measures designed to prevent global warming to how humankind begins to adapt to a warmer planet. Coping with large scale migrations, the provision and distribution of food and water, secure housing and the simple ability for us to cope will become priorities alongside measures to cut emissions. One thing seems clear – both adaptation and prevention will require significant investment and a combined approach is likely to be the most practical and beneficial. An influential 2006 review of the economic impact of climate change by Sir Nicholas Stern, a former World Bank Chief Economist, gives a dimension to the costs involved. His review suggested that the cost of inaction would be between “5 and 20 per cent of global GDP every year now and forever.” Stern calculated the cost of action to tackle the issue, or in other words the ‘insurance’ premium society pays to mitigate the risk, to be just one per cent of global GDP per annum. Action necessarily has to be a combination of ‘push and pull’ strategies. The push will come from governments in the form of regulation and taxation. Regulation and taxation and subsidies are used to good effect in the car industry, for example. Manufacturers are forced to reduce their vehicle emissions by regulation; consumers are encouraged to buy low emission cars via lower taxes. Carbon trading, which caps the amount of carbon an industry can produce and enables the trading of surpluses and deficits between participants, is another government initiative to drive a change in corporate behaviour. Perhaps, with rapidly growing awareness, the pull will come from consumers who demand that consumption and production be greener. Buying locally and with a social conscience is becoming more of a virtue, especially among more affluent consumers, and retailers are responding. A product’s greenness is becoming an integral part of its appeal.

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Institutional Response to Environmental Degradation

The Montreal Protocol 1987

The Montreal Protocol on Substances that Deplete the Ozone Layer (a protocol to the Vienna Convention for the Protection of the Ozone Layer) is an international treaty designed to protect the ozone layer by phasing out the production of numerous substances believed to be responsible for ozone depletion. The treaty was opened for signature on 16 September 1987, and entered into force on 1 January 1989, followed by a first meeting in Helsinki, May 1989. Since then, it has undergone seven revisions, in 1990 (London), 1991 (Nairobi), 1992 (Copenhagen), 1993 (Bangkok), 1995 (Vienna), 1997 (Montreal), and 1999 (Beijing). It is believed that if the international agreement is adhered to, the ozone layer is expected to recover by 2050. Due to its widespread adoption and implementation it has been hailed as an example of exceptional international co-operation, with Kofi Annan quoted as saying that "perhaps the single most successful international agreement to date has been the Montreal Protocol". The two ozone treaties have been ratified by 197 states and the European Union making them the most widely ratified treaties in United Nations history. June 08, 2013: President Obama and President Xi agreed on an important new step to confront global climate change. For the first time, the United States and China will work together and with other countries to use the expertise and institutions of the Montreal Protocol to phase down the consumption and production of hydrofluorocarbons (HFCs), among other forms of multilateral cooperation. A global phase down of HFCs could potentially reduce some 90 Giga tons of CO2 (or 24.5 Giga tons of Carbon) equivalent by 2050. (Equal to roughly two and a half years’ worth of current global greenhouse gas emissions in 35 years) The political focus on the ozone layer and HFCs can be seen as necessary in a scenario where there is growing public disquiet generally on the effects of human activity on the sustainability of the bio-sphere as we know it. Something must be seen to be done. Expounding on policy that addresses the numbers and impacts; that advocates cut backs in energy consumption and seeks to cover the costs of mitigating the fall out of ‘no-matter-what’ changes in the bio-sphere in a climate of austerity and economic downturn is a political ‘hot potato’. This is a world of election cycles,

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sound bites, quarterly results and ‘market-sentiment’; a world economy driven by the ‘grow and consume’ paradigm and fuelled predominantly by fossil fuel. However time is running out and the matter can no longer be ‘kicked down the road’. Today research and mitigation programmes operate in an environment where there is broad recognition that there are neither soft options nor the possibility of ‘good days ahead’.

The Intergovernmental Panel on Climate Change (IPCC)

The IPCC Special Report on Emissions Scenarios (SRES, 2000) projects an increase of global GHG emissions by 25 to 90% (CO2-eq) between 2000 and 2030, with fossil fuels maintaining their dominant position in the global energy mix to 2030 and beyond. More recent scenarios without additional emissions mitigation are comparable in range.

This figure from the US’s EPA shows projected greenhouse gas concentrations for four different emissions scenarios. The top three scenarios assume no explicit climate policies. The bottom green line is an illustrative “stabilization scenario,” designed to stabilize atmospheric carbon dioxide concentration at 450 parts per million by volume. Source: USGCRP (2009)

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The IPCC Fourth Assessment Report AR4 2007

There is high agreement and much evidence that with current climate change mitigation policies and related sustainable development practices, global GHG emissions will continue to grow over the next few decades.

Continued GHG emissions at or above current rates would cause further warming and induce many changes in the global climate system during the 21st century that would very likely be larger than those observed during the 20th century

Left Panel: Global GHG emissions (in GtCO2-eq) in the absence of climate policies: six illustrative SRES

3 marker

scenarios (coloured lines) and the 80th

percentile range of recent scenarios published since SRES (post-SRES) (Gray shaded area). Dashed lines show the full range of post-SRES scenarios. The emissions include CO2, CH4, N2O and F-gases. Right Panel: Solid lines are multi-model global averages of surface warming for scenarios A2, A1B and B1, shown as continuations of the 20

th-century simulations. These projections also take into account emissions of short-lived

GHGs and aerosols. The pink line is not a scenario, but is for Atmosphere-Ocean General Circulation Model (AOGCM) simulations where atmospheric concentrations are held constant at year 2000 values. The bars at the right of the figure indicate the best estimate (solid line within each bar) and the likely range assessed for the six SRES marker scenarios at 2090-2099. All temperatures are relative to the period 1980-1999

Global climate change has already had observable effects on the environment. Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have shifted and trees are flowering sooner.

3 The Special Report on Emissions Scenarios (SRES) is a report by the Intergovernmental Panel on Climate Change (IPCC) that was published in 2000. The greenhouse gas emissions scenarios described in the Report have been used to make projections of possible future climate change. The SRES scenarios, as they are often called, were used in the IPCC Third Assessment Report (TAR), published in 2001, and in the IPCC Fourth Assessment Report (AR4), referred above, published in 2007.

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Effects that scientists had predicted in the past would result from global climate change are now occurring: loss of sea ice, accelerated sea level rise and longer, more intense heat waves. Scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gasses produced by human activities. The Intergovernmental Panel on Climate Change (IPCC), which includes more than 1,300 scientists from the United States and other countries, forecasts a temperature rise of 2.5 to 10 degrees Fahrenheit (1.4 to 5.5 degrees C) over the next century. According to the IPCC, the extent of climate change effects on individual regions will vary over time and with the ability of different societal and environmental systems to mitigate or adapt to change. The IPCC predicts that increases in global mean temperature of less than 1.8 to 5.4 degrees Fahrenheit (1 to 3 degrees C) above 1990 levels will produce beneficial impacts in some regions and harmful ones in others. Net annual costs will increase over time as global temperatures increase. "Taken as a whole," the IPCC states, "the range of published evidence indicates that the net damage costs of climate change are likely to be significant and to increase over time."

Regional impacts of global change forecast by the IPCC: North America: Decreasing snowpack in the western mountains; 5-20 percent increase in yields of rain-fed agriculture in some regions; increased frequency, intensity and duration of heat waves in cities that currently experience them. Latin America: Gradual replacement of tropical forest by savannah in eastern Amazonia; risk of significant biodiversity loss through species extinction in many tropical areas; significant changes in water availability for human consumption, agriculture and energy generation. Europe: Increased risk of inland flash floods; more frequent coastal flooding and increased erosion from storms and sea level rise; glacial retreat in mountainous areas; reduced snow cover and winter tourism; extensive species losses; reductions of crop productivity in southern Europe. Africa: By 2020, between 75 and 250 million people are projected to be exposed to increased water stress; yields from rain-fed agriculture could be reduced by up to 50 percent in some regions by 2020; agricultural production, including access to food, may be severely compromised. Asia: Freshwater availability projected to decrease in Central, South, East and Southeast Asia by the 2050s; coastal areas will be at risk due to increased flooding; death rate from disease associated with floods and droughts expected to rise in some regions.

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CCS - Carbon, Capture and Storage CCS technology involves three major steps:

Capture The separation of CO2 from other gases produced at large industrial process facilities such as coal and natural gas power plants, oil and gas plants, steel mills, cement plants, etc.

Transport Once separated, the CO2 is compressed and transported via pipelines, trucks, ships or other methods to a suitable site for geological storage.

Storage CO2 is injected into deep underground rock formations, often at depths of one kilometre or more.

Why CCS? The world is facing a climate challenge. To avoid dangerous climate change, the global average temperature rise must be capped at 2oC relative to pre-industrial times. To achieve this, we are dependent on a revolutionary scale of CO2 mitigation that could see CCS contribute between 15 and 55 per cent of the required abatement to the year 2100 (2005, IPCC Special Report). Electricity sourced from fossil fuels accounts for more than 40 per cent of the world’s energy-related CO2 emissions (2011, IEA CO2 Emissions from Fuel Combustion).

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Another 25 per cent of emissions come from large–scale industrial processes such as iron and steel production, cement making, natural gas processing and petroleum refining. Demand for fossil fuels is increasing, especially in developing countries, where a significant percentage of the population has no access to electricity. CCS is one of a suite of technologies that will all be required to combat climate change, including renewables, nuclear and energy efficiency. The importance of CCS as one of the tools against global warming is highlighted in a report by the International Energy Agency, which found that CCS could contribute to a 19 per cent reduction in global CO2 emissions by 2050, and that fighting climate change could cost over 70% more without CCS.

IEA Energy Technology Perspectives 2010

CCS can be applied to fossil fuel-fuelled electricity generating plant, such as coal or gas fired power stations. Fossil fuel plants with CCS have a key role to play in providing a balanced energy supply, which can cope with rapid changes in demand, and intermittency of supply, which nuclear and renewables cannot. CCS will play a key role in providing secure, affordable, low carbon electricity in the transition to a low-carbon economy. CCS can also significantly reduce emissions from industry such as cement, steel, petroleum refining and chemical industries, and in many instances, is the only currently viable technology to do so. “CCS has a key part to play in ensuring that we can keep the lights on at the same time as fighting climate change. The International Energy Agency has estimated that globally 3,400 CCS plants will be needed by 2050 if we are to meet our critical target of 2 degrees above pre-industrial levels.”

Chris Huhne, Jan 2011, UK Secretary of State, Department of Energy and Climate Change

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Technology

The current state of CO2 injection technology can best be summarized by the conclusions reached by MIT (Massachusetts Institute of Technology) in their Environmental Assessment of Geological Storage of CO2, namely that: “The technologies and practices associated with geological CO2 sequestration are all in current commercial operation, and have been so for a decade to several decades. Such commercial operations include: enhanced oil recovery, acid gas (CO2) injection, natural gas storage and CO2 pipeline transportation. No major “breakthrough” technological innovations appear to be required for large scale CO2 transportation and storage. All the focus, technologically, is on ‘capture’. Energy from fossil fuels such as coal, oil and natural gas is released in the combustion (burning) process. The emission of CO2 is a by-product of this process. Capture technology can be applied to any large–scale emissions process, including coal–fired power generation, gas and oil production, and manufacture of industrial materials such as cement, iron, steel and pulp paper. In fact, large CO2 emitter industries around the world have applied capture technology for decades. Captured CO2 is used, for example, in the food and beverage industry and in making fertiliser. In systems where the coal is pulverised to a powder, which makes up the vast majority of coal–based power plants in North America, Australia, Europe and China, the CO2 must be separated at fairly diluted concentrations from the balance of the combustion flue gases (gas exiting via a chimney or ‘flue’). In other systems, such as coal gasification, the CO2 can be more easily separated. There are three basic types of CO2 capture: pre-combustion, post-combustion and oxyfuel with post-combustion.

Pre-combustion capture

Pre-combustion processes convert fuel into a gaseous mixture of hydrogen and CO2. The hydrogen is separated and can be burnt without producing any CO2; the CO2 can be compressed for transport. Pre-combustion capture is used in industrial processes but has not been demonstrated in much larger power generation projects. The fuel conversion steps

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required for pre-combustion are more complex than the processes involved in post-combustion, so the technology is more difficult to apply to existing power plants. Pre-combustion capture increases the CO2 concentration of the flue stream, requiring smaller equipment and different solvents with lower regeneration energy requirements. The process involves:

partially reacting the fuel at high pressure with oxygen or air and, in some cases, steam, to produce carbon monoxide and hydrogen

reacting the carbon monoxide with steam in a catalytic shift reactor to produce CO2 and additional hydrogen

separating the CO2 and,

for electricity generation, using hydrogen as fuel in a combined cycle plant.

Although pre-combustion capture involves a more radical change to power station design, most elements of the technology are already well proven in other industrial processes.

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Post-combustion capture

Post-combustion processes separate CO2 from combustion exhaust gases so that the CO2 can be captured using a liquid solvent. The CO2 is absorbed by the solvent and then released when it is heated to form a high purity CO2 stream. The process involves scrubbing the flue with a suitable solvent, such as an amine solution, to form an amine–CO2 complex, which is then decomposed by heat to release high purity CO2. The regenerated amine is recycled to be reused in the capture process. Post-combustion capture is applicable to coal–fired power stations but additional measures, such as desulphurisation of the gas stream, are required to prevent the impurities in the flue gas from contaminating the CO2 capture solvent. Two significant challenges for post-combustion capture involve:

the large volumes of gas that must be handled, requiring large–scale equipment and creating high capital costs, and

The amount of additional energy needed to operate the process.

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Post-combustion capture technology is used widely in the food and beverage industry.

Oxyfuel combustion

Oxyfuel with post-combustion processes uses oxygen rather than air for combustion of fuel. This produces exhaust gas that is mainly water vapour and CO2 that can be easily separated to produce a high purity CO2 stream. The concentration of CO2 in flue gas can be increased by using pure or enriched oxygen instead of air for combustion, either in a boiler or gas turbine. The oxygen is produced by cryogenic air separation (already used on a large scale industrially), and the CO2-rich flue gas recycled to avoid the excessively high–flame temperature associated with combustion in pure ox ygen.

The advantage of oxyfuel combustion is that, because the flue gas contains a high concentration of CO2, the CO2 separation stage is simplified. The main disadvantage is that cryogenic oxygen is expensive. Oxyfuel combustion for power generation is currently being demonstrated at a refurbished power station in Biloela, Queensland.

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CO2 from Power Generation:

The CCS cost case for power generation by different routes has been variously estimated and a 2013 illustrative summary on 2007 $ cost basis is as below. Oxy-fuel combustion which would offer a near-pure CO2 stream after dehumidification has not been covered in this particular analysis as a ‘developmental technology’.

Source: #3002000176 March 2013 Electric Power Research Institute Notes:

1. Integrated (coal) Gasification Combined Cycle (IGCC) 2. Ultra-supercritical (USC) steam generation fuelled by pulverized coal (PC) 3. Natural Gas Combined Cycle (NGCC) 4. LCOE (levelled cost of energy) is one of the utility industry’s primary metrics for the cost of

electricity produced by a generator. It is calculated by accounting for all of a system’s expected lifetime costs (including construction, financing, fuel, maintenance, taxes, insurance and incentives), which are then divided by the system’s lifetime expected power output (kWh). All cost and benefit estimates are adjusted for inflation and discounted to account for the time-value of money.

A rounded calculation based on the above indicates that CCS adds 25 to 45 (2007) US $ to the cost of producing one megawatt hour of electricity, representing between 40 and 75 per cent increase in the cost of generation.

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Range of Cost Estimates for Options for Capture, Transportation and Sequestration of CO2

The range of carbon capture cost estimates from different sources and subsequent transportation and sequestering options have been estimated to be as follows:

There is consensus in the OECD countries that CCS is a key component of GHG mitigation measures as is illustrated by the table below:

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According to the Global CCS Institute (GCCSI), as of April 2010, 238 projects involving CO2 capture, transport and/or storage are either active or planned worldwide. Of these, 80 are large-scale, integrated projects (>1 million tonnes of CO2/year for coal; >500 thousand tonnes of CO2/year for gas), where the entire CO2 capture-transport-storage chain is demonstrated; 9 are already operational, (mainly storage-oriented projects) 2 are under construction and 69 are at planning stages:

21 projects are performing feasibility studies and preliminary engineering design (most mature)

24 projects are conducting pre-feasibility studies and initial cost estimates (moderately mature)

24 projects are undertaking scoping studies (least mature). Out of these 80 projects, 44 are in the power sector and 25 in Europe. Over $26 billion in funding has been proposed by governments globally for large-scale projects.

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Mussafah Project Fact Sheet: Carbon Dioxide Capture and Storage Project

Company/Alliance: Abu Dhabi Future Energy Company (Masdar) and ADNOC

Location: Emirates Steel complex at Mussafah, UAE (United Arab Emirates) Khalifa Port and Industrial Zone (KPIZ) in Taweelah.

Trials: Abu Dhabi Company for Onshore Oil Operations (ADCO) initiated the enhanced oil recovery (EOR) project by test injection of carbon dioxide (CO2) into pilot wells in a carbonate reservoir in the MENA region of Abu Dhabi. Praxair Gulf Industrial Gases LLC, an Abu Dhabi-based subsidiary of Praxair, Inc. supplied the required CO2 and injection operations under a contract with Abu Dhabi Future Energy Company (MASDAR). The project began operations in the fourth quarter of 2009 and continued for two years till the end of 2011. A continuous supply of 60 tons per day (1.2 million standard cubic feet per day) of CO2 was provided to ADCO and was injected into one of the pilot wells. Feedstock: Natural gas Size: 0.8 Mt/yr. of CO2 or approximately 2,200 MT per day Capture Technology: Pre-combustion steel production; CO2 Fate: EOR The 90% CO2 feed stream from the Emirates Steel plant will be compressed, dehydrated and then pumped through 50km of pipeline before being injected in an onshore field, operated by Abu Dhabi Company for onshore oil operations. The project was delayed in January 2011 due to issues with negotiating prices for the carbon dioxide and electricity produced at the hydrogen plant with its two main customers: Abu Dhabi National Oil Company (ADNOC) and Abu Dhabi Water Electricity Authority (ADWEA). A CO2 injection pilot project with EOR at an onshore field completed two years injection in November 2011. The wealth of data collected over the period has encouraged the two partners to go ahead with the Emirates Steel project. The Masdar Initiative was launched in 2008 to deliver Masdar City, the world's first zero-carbon sustainable city. $15 billion is coming from the Abu Dhabi government

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for the project. Included in this venture were plans to build large-scale CCS projects. Masdar and ADNOC take carbon capture, usage and storage project forward at Emirates. Date Modified May 13, 2013

What now? Read more at http://cleantechnica.com/2011/05/05/ccs-demos-grinding-to-a-halt/#TQUm1v9EgcVAee52.99

If as few as 3,200 carbon sequestration projects were in operation around the world, that would be enough to provide more than 15% of the emissions reductions needed for a liveable climate for the next generation, says Juho Lipponen, who heads the CCS unit of the International Energy Agency in Paris. At least 25% of the 30 billion tons or so of new human-caused CO2 emitted each year comes from burning coal to generate power. If we can limit the rise in CO2 to 450 parts per million by 2050, then we have a 50% chance of keeping global warming below 2 degrees (3.6 degrees Fahrenheit) by 2100, say scientists. (While 2 degrees is far from an ideal target, it is politically the most achievable target that is not completely catastrophic.) However, globally there are now fewer than half a dozen full-scale CCS projects in operation around the world. There were as many as 235 proposed CCS projects globally, 45 of them full-scale. Now there is one in the US (Wyoming), two in Norway, one in the Netherlands, one in Canada, and one in Algeria. All but one of these capture carbon from natural gas, which has only about half the greenhouse gas emissions of coal – because that is easier and cheaper to do. Coal is where the greatest need is. But with the collapse of climate legislation that would have put a compulsory cap on carbon, polluter-pays funding for potential projects is now non-existent in the US. Most of the eight or nine projects under way in the United States are now in doubt, says Howard Herzog, who researches sequestration at the Massachusetts Institute of Technology in Cambridge. “A lot of the momentum that has been built up is just going to grind to a halt,” he says. “My hope is that we will see a few projects go ahead and serve as an example of what can be done when the politics turn around.”