Low Emissions Coal Technologies
What are low emissions coal technologies?
Low emissions coal technologies refer to technologies that are designed to increase the energy efficiency and improve the environmental performance of burning coal to produce electricity. These technologies aim to significantly reduce greenhouse gas emissions, particularly carbon dioxide (CO2), and their associated environmental impacts, as well as reduce waste from the process in coal extraction, preparation and utilisation. They vary in design and the stage of development, from early research and development to commercial application. When used in combination with techniques to clean carbon from greenhouse gas emissions for safe and permanent storage (Carbon Capture and Storage), these technologies can dramatically reduce greenhouse gas emissions from coal and gas powered electricity generation, as well as industrial processes.
Why do we need these technologies?
75% of electricity used in NSW is generated from coal-fired power stations.
Coal extraction is one of the most significant industries in New South Wales. Coal is also the key requirement for two other building blocks of modern society – the production of steel and cement. Not only does coal contribute valuable dollars and jobs to the NSW economy, it also provides 75% of the electricity in NSW.
Although coal provides most of the energy required to power our industries and homes, the burning of coal to produce electricity is a carbon-intensive energy option and emits a substantial amount of greenhouse gas emissions.
NSW’s coal fired power stations accounted for 64.1 million tonnes of CO2 emissions in 2010. This form of power generation emits 40.7 per cent of NSW total greenhouse gas emissions. This figure is likely to rise as the demand for electricity grows.
The use of coal as a reliable and economically sustainable energy source in NSW, and indeed throughout the world, is not expected to change considerably over the near to intermediate term. In a future carbon-constrained world, solutions will be required to reduce the greenhouse gas emissions associated with generating electricity from coal.
Coal accounts for about one quarter of the world’s energy demand and is used to produce 42% of the world’s electricity. Coal energy demand and coal-generated energy are expected to increase by about 1.25 times and 1.50 times, respectively, toward 2035.
While increasing the combustion efficiency of coal will help reduce greenhouse gas emissions, any significant reductions in carbon dioxide (CO2) emissions from coal fired power stations can only be achieved by capturing CO2 emissions before or after the coal is burnt, and then safely storing it in a secure and permanent manner. This is a process known as Carbon Capture and Storage.
International Energy Agency (IEA) analysis assigns a critical role for Carbon Capture and Storage in keeping temperature increases less than 2°C by 2050. In this scenario, Carbon Capture and Storage technologies could account for more than one-fifth (22%) of needed global emissions reductions between 2015 and 2050. Power stations and other industrial sources, such as gas plants, refineries, steel mills and cement manufacturing where Carbon Capture and Storage can be applied, account for 17 gigatonnes (GtCO2), or 57% of global annual energy related CO2 emissions. The scale of potential future deployment of Carbon Capture and Storage is enormous, as nearly 123 GtCO2 need to be safely stored in geologic formations through 2050.
Source: Energy Technology Perspectives 2012, International Energy Agency.
Whilst there have been small scale trials of various Carbon Capture and Storage technologies and six commercial scale gas production facilities, as well as a synthetic fuel and fertiliser facility in operation, there is no fully integrated industrial-scale coal-fired power station built to date. That is, one which demonstrates at a commercial scale the various stages from combustion, separation, transportation and storing of CO2.
What is Carbon Capture and Storage?
Carbon dioxide Capture and Storage uses low emission coal technologies to efficiently burn coal and reduce the output of CO2 emissions, but then also separates out the CO2 and captures it before it is vented into the atmosphere. It is then transported to a suitable storage site and pumped into deep underground rock to be securely and permanently stored away from the atmosphere. The storage site is fully characterised and understood to provide the certainty of permanent storage.
To capture the CO2 it must be first be separated from other gases that result from combustion or processing. Some gas streams resulting from industrial processes, such as natural-gas purification and ammonia production, are very pure to begin with while others may not be.
Three major options are available for the capture of carbon dioxide;
- Post-combustion capture separates the CO2 from the other flue gases using an organic solvent or membrane.
- Pre-combustion capture starts by processing the primary fuel with steam and air or oxygen. The resulting carbon monoxide then reacts with steam in a second reactor. This produces hydrogen for making energy or heat as well as CO2, which is separated out and captured.
- Oxy-fuel combustion capture uses oxygen instead of air to burn the fuel. It results in a flue gas containing mainly water vapour and CO2. The water vapour is removed by cooling and compressing the gas stream. This technology, which is still in its demonstration phase, can capture nearly all the CO2 produced. The need for additional gas treatment systems to produce the oxygen and to remove pollutants such as sulphur and nitrogen oxides, however, lowers the CO2 avoided to about 90%.
To store the CO2 it is compressed into a supercritical state (so it performs like a liquid) and is easier to transport by way of pipeline, road or sea transport to an injection well. It is then injected into a secure and deep underground geological storage formation, often at depths past 800 metres. This can include gas storage reservoirs such as depleted oil and gas fields, un-mineable coal seams and deep saline formations where the CO2 can be monitored long after the closure of the site. Alternative storage methods and options are also being considered such as mineral carbonation and bio-algal sequestration.
The major application of Carbon Capture and Storage is to reduce CO2 emissions from fossil fuel power plants, principally coal and natural gas. However, Carbon Capture and Storage can also be applied to CO2 intensive industries such as cement, iron and steel, petrochemicals and oil and gas processing. The International Energy Agency estimates that by 2050, Carbon Capture and Storage from power generation, industry and fuel transformation could contribute up to 19% of the effort to reduce global CO2 emissions (or 9.4 Gigatonnes of CO2 per year by 2050). Therefore, this group of technologies is expected to play a significant role in dealing with the complex and challenging problem of providing reliable, economical and environmentally sustainable electricity production in a future carbon-constrained world.
What is the NSW State Government doing?
NSW is driving major change in the energy sector, stimulating the deployment of new technologies and lower carbon fuels to ensure our future power supply is cleaner, affordable and reliable. The NSW Government is active in reducing greenhouse gas emissions through a number of initiatives which include:
- Coal Innovation NSW
- Coal Innovation NSW Fund
- Coal Innovation NSW Fund Research and Development Projects
- NSW Carbon Capture and Storage Demonstration Project
- NSW Storage Capacity Project
- 2010 NSW Low Emissions Coal Technologies Summit
Amongst these initiatives was the establishment of Coal Innovation NSW and the $100 million Coal Innovation NSW Fund. Through this Fund the NSW Government is supporting a total of nine projects through a comprehensive $13 million Research and Development program to drive technological developments in low emissions coal technologies that cover the full breadth of coal application in NSW from:
- Fugitive methane emissions from coal mines
- Coal combustion and electricity generation efficiency
- Post-combustion capture of carbon dioxide (CO2)
- Storage of captured carbon dioxide (CO2)
- Public consultation and community awareness
Working in collaboration with others
Through the Coal Innovation NSW Fund, the NSW Government is providing financial support and partnering with such project proponents as:
- Centennial Coal
- Commonwealth Scientific and Industrial Research Organisation (CSIRO)
- Priority Research Centre for Energy, University of Newcastle
- Research Institute for Social Inclusion and Well-being, University of Newcastle
- UCC Energy Pty Ltd
More information on these projects can be found under Coal Innovation NSW Fund Research and Development Projects.
The NSW Government is a member of the Australian National Carbon Capture and Storage Council. The Council brings together key stakeholders to advise the Australian Government on the accelerated development and deployment of CCS in Australia, including a portfolio of industrial-scale demonstration projects in the period 2015-2020 and commercial deployment from 2020.
The Council builds on the work of the National Low Emissions Coal Council and the Carbon Storage Task Force and will oversee the implementation of the National Low Emissions Coal Strategy and the National Carbon Mapping and Infrastructure Plan.
The NSW Government is a member of the Global Carbon Capture and Storage Institute (Global CCS Institute) which works collaboratively to accelerate the worldwide commercial deployment of Carbon Capture and Storage at scale. The Institute connects parties around the world to address issues and learn from each other to accelerate the deployment of CCS projects through sharing knowledge, advocacy and assisting projects. The cross-cutting membership comprises government, industries, research organisations and other interested stakeholders.
More information: www.globalccsinstitute.com.
NSW Trade & Investment is also a participant in the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC), one of the world’s leading collaborative research organisations focused on carbon dioxide capture and storage technologies. It has more than 100 scientists working to develop safe and economic geosequestration technologies. The organisation is also conducting the Otway Project, which is Australia’s first demonstration of deep geological storage (or geosequestration) of carbon dioxide, the most common greenhouse gas. The project will help inform public policy and industry decision-makers, while also providing assurance to the community. The CO2CRC has also developed a CCS Atlas for New South Wales Australia. The Atlas provides a variety of maps and diagrams that summarises a range of geological, topographic, industrial, cultural and other features which influence the extent to which Carbon Capture and Storage may be used in NSW in the future as a greenhouse gas mitigation option.
More Information: www.co2crc.com.au
The Intergovernmental Panel on Climate Chance (IPCC) Special Report on Carbon Dioxide Capture and Storage provides invaluable information for researchers, policymakers, scientists and engineers. www.ipcc.ch.
The International Energy Agency (IEA) is an intergovernmental organisation that conducts a broad programme of energy research, data compilation, publications and public dissemination on the latest energy policy analysis and recommendations on good practices. www.iea.org.
The IEA Greenhouse Gas R&D Programme (IEAGHG) is an international collaborative research programme established in 1991 as an Implementing Agreement under the International Energy Agency (IEA). IEAGHG studies and evaluates technologies that can reduce greenhouse gas emissions derived from the use of fossil fuels. The Programme aims to provide its members with definitive information on the role that technology can take in reducing greenhouse gas emissions. www.ieaghg.org.
The Carbon Sequestration Leadership Forum (CSLF) is a Ministerial-level international climate change initiative that is focused on the development of improved cost-effective technologies for the separation and capture of carbon dioxide (CO2) for its transport and long-term safe storage. The mission of the CSLF is to facilitate the development and deployment of such technologies via collaborative efforts that address key technical, economic and environmental obstacles. The CSLF also promotes awareness and champion legal, regulatory, financial, and institutional environments conducive to such technologies. www.cslforum.org/aboutus/index.html.