House of Commons - Science and Technology

Hansard

Archives

Research

HOC Publications

HOL Publications

Committees

Select Committee on Science and Technology First Report

2 BACKGROUND

Definitions

CARBON CAPTURE AND STORAGE

5. Carbon Capture and Storage (CCS) refers to the capture and storage of carbon dioxide (CO₂) from emissions to prevent it from entering the atmosphere. The term 'CCS' refers to the application of carbon abatement technologies to industrial emissions, rather than to biological processes such as the take-up and storage of CO₂ by forests. The term 'carbon sequestration' is often applied to these biological processes, although it may sometimes also be used to denote CCS.

6. CCS can be broadly divided into three stages: capture, transport and storage. An overview of the process as applied to a power plant is provided in Figure 1. In brief, CO₂ is captured from the power plant either before or after combustion, prior to being compressed for transportation and injection into the storage site, typically a depleted oil or gas field or a saline aquifer. Further information on the capture, transportation and storage processes is contained in chapter three.

Figure 1: An overview of the CCS process

7. The objective of this Report is not to provide a detailed technical appraisal of CCS technology, which can, instead, be found in the recently published Intergovernmental Panel on Climate Change (IPCC) Special Report on CCS.[3] Useful and accessible summaries of CCS are also provided by two recent publications from the Parliamentary Office of Science and Technology: POSTnotes 238 and 253 which focus, respectively, on CO₂ storage and cleaner coal technologies.[4] In addition, the House of Commons Environmental Audit Committee will be publishing in early 2006 a Report examining investment options for meeting future requirements for new electricity generating capacity.

ENHANCED OIL RECOVERY

8. Enhanced Oil Recovery [EOR] is a special case of CCS.[5] CO₂ pumped into a near-depleted field dissolves in the oil, making it more mobile and easier to extract. This can lengthen the life of the field and increase the overall yield of oil. EOR is an established onshore technology but it has not so far been used commercially offshore. Although some of the injected CO₂ returns to the surface with the oil, this is recaptured and added back to the CO₂ being injected. The climate change benefit of EOR arises if the CO₂ has been captured from fossil fuel combustion and if most of it is left in the reservoir at the end of its productive life. Further discussion of EOR can be found in paragraph 108.

LEAKAGE

9. It should be noted that throughout this Report the term 'leakage' will be used to refer to the unintended physical release of CO₂ from storage sites or pipelines transporting CO₂ between capture and storage sites. This should be distinguished from the definition of leakage commonly used in climate change discussions to refer to the spatial displacement of sources of emissions from one place to another.

GASIFICATION AND PULVERISED FUEL PLANT

10. There are two main methods for generating electricity from coal: combustion and gasification. The most common type of combustion plant is often called a 'pulverised fuel' (PF) station since the coal is finely ground before being injected into the combustion chamber. Superheated steam is then produced in a boiler and used to drive a steam turbine to produce electricity. Integrated gasification combined cycle (IGCC) plant employ gasification technology. The coal is converted to a synthesis gas (or 'syngas') which is fired in gas turbines to produce electricity. The hot exhaust gases are then used to produce superheated steam to drive a steam turbine, producing further electricity. IGCC is a newer and more efficient technology than PF and there are currently only four coal-fired IGCC plant around the world.[6]

Box 1: Energy And Emissions Units

Climate change policy

11. Climate change has been steadily working its way up the Government's list of policy priorities and formed one of the two key themes of the UK's G8 Presidency in 2005. It is widely accepted that rising atmospheric concentrations of CO₂ are fuelling climate change and ocean acidification and, in recognition of this, the UK, like other countries, is taking steps to reduce its CO₂ emissions. Global atmospheric carbon dioxide levels have risen from 280 parts per million (ppm) to 380 ppm since pre-industrial times - an increase attributed largely to the burning of fossil fuels.[7] Global average temperatures have risen by 0.6 degrees Celsius over the past century and further temperature increases, rising sea levels and a higher frequency of extreme weather events are predicted as CO₂ levels continue to rise.[8] There is also growing evidence of ocean acidification caused by higher levels of atmospheric CO₂ being absorbed by the oceans. This is thought to be exerting a detrimental effect on marine ecosystems.[9] For many years discussions about greenhouse gas emissions have focussed on limiting CO₂ levels to 550 ppm (approximately double pre-industrial levels) but many scientists now argue that even this level of CO₂ could be dangerously high.[10] The latest evidence suggests that atmospheric CO₂ concentrations would need to stay below 400 ppm in order to limit average global temperature increases to 2 degrees Celsius above pre-industrial levels. [11]

12. The UK has committed to meeting the following CO₂ emissions reduction targets:

Kyoto protocol target to reduce CO₂ emissions by 12.5% below 1990 levels by 2008-2012—this represents the UK's share of the EU Kyoto target; and
Domestic targets to reduce CO₂ emissions by 20% below 1990 levels by 2010, and by 60% below 1990 levels by 2050.

13. On current progress, it would seem that the UK is on track to meet its Kyoto Protocol target of a 12.5% reduction by 2008-2012. However, present Government projections suggest that CO₂ emissions will be around 13% below the 1990 level by 2010, significantly short of the domestic target of 20%.[12] Moreover, if the UK continues along its present trajectory, it will have little hope of meeting the Government's longer term domestic target of a 60% reduction in CO₂ emissions by 2050. A comprehensive summary of climate change mitigation in the UK is provided by the House of Commons Environment, Food and Rural Affairs Committee's 2005 Report on climate change.[13]

ROLE OF CCS IN CLIMATE CHANGE MITIGATION

14. CCS provides a potential means of decreasing emissions of CO₂. The technology is generally best applied to large stationary sources of emissions, such as power plant. In 2002, total UK emissions of CO₂ were estimated to be 536 Mt, of which 228 Mt resulted from power generation. Twenty UK power plants alone were responsible for emitting 119 Mt of CO₂.[14] It is expected that fitting a power plant with CCS could reduce associated CO₂ emissions by around 85%, so the application of CCS technology to power plant could have a dramatic effect on CO₂ emissions. BP told us that if CCS was "applied to only 5% of the new electricity generating capacity which the world is projected to require by 2050, the world would have the potential of reducing global CO₂ emissions by around one billion tonnes [1 Gt] a year".[15] CCS also has the potential to contribute to reducing industrial emissions through direct application to energy-intensive processes such as oil refining and steel and cement manufacture. In addition, it may be possible for CCS to contribute to reducing emissions from the transport sector by providing a low carbon means of generating electricity for powering electric vehicles, or hydrogen for hydrogen-fuelled vehicles. This Report focuses on the use of CCS in power generation but the potential for these additional applications of CCS is discussed further in paragraph 39.

15. Clearly, CCS is not the only possible approach to reducing CO₂ emissions and a multi-pronged approach will need to be adopted if reductions are to be made in the timeframe desired. Other elements of the strategy may include reducing energy consumption, increasing energy efficiency and moving from carbon intensive sources of energy such as conventional coal to gas, nuclear and, in particular, renewables. Enhancing sequestration of CO₂ in so-called biological sinks, e.g. forests, could also play a role. The IPCC has produced a number of publications providing detailed information about these various options. The previous House of Commons Science and Technology Committee also published a Report entitled Towards a Non-Carbon Fuel Economy: Research, Development and Demonstration in 2003.[16] While these other measures will undoubtedly make key contributions to mitigating CO₂ emissions, detailed consideration of their respective roles is not within the remit of this Report.

INTERNATIONAL CONTEXT

16. The UK is responsible for around 2% of global CO₂ emissions. Whilst this country is making progress in the right direction, CO₂ emissions from some other countries are not only increasing, but are expected to continue to do so for the foreseeable future. According to the International Energy Agency (IEA), global emissions of CO₂ will be 52% higher by 2030 unless the world curbs its energy consumption and, even if developed nations implement climate change mitigation policies, global CO₂ emissions are still expected to rise by about 30% by 2030.[17]

17. Much of this growth will be attributable to the increasing use of coal by China and India. At present, the US is the largest consumer of coal for power generation but China and India, which have substantial coal reserves, are the fastest growing users. Current global coal-fired electricity generation capacity is estimated to be around 1000 Gigawatts. However, as Dr Nick Riley from the British Geological Survey told us in oral evidence, "China is installing one Gigawatt of coal powered generation a week. That is four megatons of CO₂ a week increase in China just from its coal plant generation".[18] Brian Morris, Head of Carbon Abatement Technologies at the DTI, also told us of his concerns over China and India's plans to build a vast fleet of new coal-fired plant: "Each year they are putting in coal fired power plants equal to the total capacity of the UK […] What is worrying is the possibility of carbon lock in".[19]

18. Current forecasts predict that by 2030, coal-fired power in India and China will add 3,000 million extra tonnes of CO₂ to the atmosphere every year—equivalent to around 13 times the UK's current total CO₂ emissions from power generation.[20] During the same period, emissions from China alone are forecast to grow by as much as those of the entire industrialised world. Other middle income countries such as Brazil may also add substantially to global emissions over this period. It is indisputable that—in the absence of CCS—fossil fuel consumption in countries such as China and India will have a profound and potentially catastrophic impact on global atmospheric CO₂ levels, eclipsing any reductions made by the UK and others. The implications of this are discussed further in paragraphs 67-70.

19. Brian Morris, Head of Carbon Abatement Technologies at the DTI, stressed that China was "very aware of the consequences of climate change [and] the damage that burning coal without trying to control the emissions is going to do not just to the planet but to their own prospects in the future".[21] Mr Morris' view contrasted with evidence given by BP's Gardiner Hill, who said that in his experience, China was "not prepared to invest money on reducing CO₂ emissions".[22] Mr Hill told us: "China has particularly large challenges facing it today. They are not particularly focussed on the issues of climate change; they are much more focussed on providing the energy they need to develop their country".[23] However, Mr Hill proposed that China's concerns over air quality might provide an alternative entry point for promoting the uptake of CCS technologies: "I think when we get to the air quality issues conversation, there is an opportunity for us also to adopt CCS type technologies which will address air quality and start to address climate change. If we can make these links, we can perhaps make inroads to a country like China quicker than we would otherwise if we just went in on the climate change plan".[24] We consider the potential for CCS to help curb the forecast growth in emissions from China and India in chapter four.

UK energy policy

20. On 29 November 2005, the Government launched a fundamental review of UK energy policy. The Government described the purpose of the review as being to "assess progress against the four goals set by the 2003 energy White Paper:

to put ourselves on a path to cut the UK's carbon dioxide emissions—the main contributor to global warming—by some 60 per cent. by about 2050 with real progress by 2020;

to maintain the reliability of energy supplies;

to promote competitive markets in the UK and beyond, helping to raise the rate of sustainable economic growth and to improve our productivity; and

to ensure that every home is adequately and affordably heated".[25]

The statement emphasised that the Energy Review "will consider all options including the role of current generating technologies, such as renewables, coal, gas and nuclear power, and new and emerging technologies, for example carbon capture and storage". Malcolm Wicks, the Energy Minister, has subsequently said: "Within the context of this review, Carbon Capture and Storage is increasingly becoming a serious longer-term option" and told us in oral evidence that the Government was "very, very interested" in it.[26]^,[27]

21. In addition, the UK Climate Change Programme, which lays out the Government's policies for achieving its national target of reducing CO₂ emissions to 20% below 1990 levels by 2010, is currently under review and Sir Nicholas Stern, Head of the Government Economic Service, has also been charged with leading a review of the economics of climate change, due to be published in Autumn 2006.

GOVERNMENT ACTION ON CCS

22. A review of CCS was already underway when the 2003 Energy White Paper was published. The White Paper also included a commitment to facilitate a demonstration of CO₂-based EOR, as well as acknowledging "the potentially significant strategic role that might be played by CCS in longer-term energy security".[28] Over the last three years the DTI has published three reports pertaining to CCS:

Review of the Feasibility of Carbon Dioxide Capture and Storage in the UK (September 2003);[29]
Implementing a Demonstration of Enhanced Oil Recovery Using CO₂ in the North Sea (May 2004);[30] and
Carbon Abatement Technologies (CAT) Strategy for Fossil Fuel Use (June 2005).[31]

23. The CAT Strategy states that fossil fuels will be a major source of energy for decades to come and, if the UK is to meet its climate change targets, they will have to be used much more cleanly than at present. It further acknowledges that technologies to make fossil fuels more environmentally acceptable need to be developed and brought to market. The Strategy identified three technology areas which could deliver carbon savings from fossil use:

Higher efficiency power generation (up to 20% saving);
Co-firing with lower carbon fuels such as biomass (up to 10% saving); and
Carbon Capture and Storage (up to 85% saving).[32]

The modelling work undertaken for the Strategy demonstrated that, under a number of scenarios, CCS would need to be deployed to some degree if the UK was to meet its target to reduce CO₂ emissions by 60% by 2050. The Strategy also emphasised the need for cost reduction, especially at the capture stage, and for demonstration of safe and reliable geological storage. It additionally accepted the need for Government support to enable CCS to become commercially viable.[33] These findings are discussed in detail in the body of this Report.

24. Overall responsibility for CCS technologies lies with the Minister for Energy in the DTI but several Government Departments have an interest in the subject. The DTI Energy Group is responsible for Government policy to stimulate R&D for CCS technologies and enable them to be brought to market by industry. The Office of Science and Technology (OST) allocates Science Budget funding to the Research Councils which are, in turn, responsible for decisions on the scientific merits of specific investments in R&D in universities and Research Council institutes. The Department for the Environment, Food and Rural Affairs (DEFRA) has an interest in CCS technologies due to their potential to reduce carbon emissions from fossil fuels. HM Treasury's involvement relates to overall investment decisions and setting regulatory and investment frameworks which may impact on the development and deployment of CCS technologies. Finally, as discussed in chapter five, the Environment Agency and Health and Safety Executive additionally have responsibilities that relate to CCS technology.

25. Energy policy has been in a state of flux with many recent reviews and initiatives. By the end of 2006 the Government should have done the work necessary to establish a settled policy, at least for the medium term. Previous Government reviews have already identified a potential contribution for CCS in the UK energy portfolio. We now explore how this potential can be realized within wider energy policy and the conditions that would be required to maximise this.

3 IPCC, Special Report on Carbon Dioxide Capture and Storage, Autumn 2005, www.ipcc.ch/activity/srccs/index.htm. Back

4 Carbon Capture and Storage, POSTnote 238, Parliamentary Office of Science and Technology, March 2005 and Cleaner Coal, POSTnote 253, Parliamentary Office of Science and Technology, December 2005. Back

5 Throughout this Report, CCS refers to EOR using CO₂ (CO₂-EOR) rather than other approaches to EOR. Back

6 See POSTnote 253 for further information. Back

7 E.g. Rapid Climate Change, POSTnote 245, Parliamentary Office of Science and Technology, July 2005. Back

8 E.g. See IPCC, Climate Change 2001: The scientific basis, 2001 and Avoiding Dangerous Climate Change, International Symposium on the Stabilisation of Greenhouse Gas Concentrations, Report of the International Scientific Steering Committee, Met Office, May 2005. Back

9 The Royal Society, Ocean acidification due to increasing atmospheric carbon dioxide, June 2005. Back

10 E.g. Rapid Climate Change, POSTnote 245, July 2005, Parliamentary Office of Science and Technology. Back

11 Avoiding Dangerous Climate Change, International Symposium on the Stabilisation of Greenhouse Gas Concentrations, Report of the International Scientific Steering Committee, Met Office, May 2005. Back

12 Greenhouse gas emissions figures released today, Department for the Environment, Food and Rural Affairs press release 134/05, 21 March 2005. Back

13 Ninth Report from the Environment, Food and Rural Affairs Committee, Session 2004-05, Climate Change: looking forward, HC 130-I. Back

14 Department for Trade and Industry, Monitoring Technologies for the Geological Storage of CO₂, Technology Status Report, Cleaner Fossil Fuels Programme, March 2005. Back