APPENDIX 4
Memorandum from the British Geological
Survey
EXECUTIVE SUMMARY
1. Underground storage of CO2 is the critical
path to decarbonising fossil fuels. Without public acceptance
there will be no CO2 storage. Most concern from the public, NGOs
and regulators is the risk of leakage from geological storage.
This concern needs to be balanced against the current situation
of 100% "leakage" direct to atmosphere from fossil fuel
emissions.
2. Storage integrity will be required for
many thousands of years. Methods and best practice for site selection,
characterization, risk assessment, monitoring and verification
of the CO2 in the subsurface are required. Leakage tolerance thresholds
need to be defined for different fluxes and modes of leakage for
the purposes of carbon trading, environmental protection, health
and safety, and intervention/remediation strategies. Identifying
these thresholds will require deliberate release experiments and
study of natural CO2 seeps.
3. Because of its hydrocarbon infrastructure,
sedimentary basins and large point source CO2 emissions, together
with the need to modernise/replace power plants, the UK is well
placed to lead, develop and take advantage of CCS. With the planned
level of decommissioning of North Sea infrastructure over the
next 15 years there is a brief time window in which to harness
this offshore investment before it is lost.
4. CO2 capture from natural gas streams
and injection into oil fields, for enhanced hydrocarbon production
are well-proven technologies that have been used extensively in
the oil and gas industry for over 30 years, particularly in North
America. There are over 70 such projects. CO2 storage is a passive
bi-product of these operations, only a few of which are being
monitored for storage performance. Dedicated geological CO2 storage
is relatively new with only two large-scale industrial projects,
worldwide (Algeria and Norway) injecting into in aquifers (since
1996 and 2004) at c 1Mt/year scale.
5. Storage estimates for oil and gas fields
can be made relatively accurately. If CO2 is injected as part
of oil and gas production, there are no regulatory barriers for
the UK.
6. Saline aquifers, principally offshore
in the UK, offer even greater potential storage capacities, but
estimating their capacity is more difficult. In addition, greater
risks of possible leakage could be associated with these unproven
"traps". Major research effort should be focused on
improving these estimates. Regulation is unclear outside hydrocarbon
production operations.
7. CO2 capture from power plant, especially
post-combustion, is the highest cost of the CO2 capture and storage
(CCS) chain. Significant efficiency improvements to the capture
process would bring more opportunities to deploy CCS. Transport
costs are dependent on the distance to storage and whether new
or existing infrastructure is used. The most efficient transport
is by pipeline. Costs for geological storage, including subsequent
monitoring, are significantly less than capture.
INTRODUCTION
8. BGS is the national geological survey
(www.bgs.ac.uk) and is a component body of the Natural Environment
Research Council. Since 1992 BGS has been the UK's leading research
centre on the geological storage of CO2. It co-ordinates the
European Research Network of Excellence (CO2GeoNet) and is involved
in the bulk of EC Framework projects on geological storage. BGS
is closely involved with the DTI which recently launched the DTI/DEFRA
Carbon Abatement Technology (CAT) Strategy. BGS participated in
DTI missions to North America and Australia to assess the state
of CCS technology there. It is also involved with the UKERC and
TSEC joint research council initiatives. BGS ran the workshop
on geological storage at the recent G8 energy research workshop
and is on technical working groups of the US led Carbon Sequestration
Leadership Forum (CSLF) and the IEA. BGS is also a member of BP's
scientific advisory board. BGS has co-authored the forthcoming
UN IPCC assessment report on CCS. The benefits of international
collaboration, transparency and close involvement with stakeholders
in developing CCS technologies have been at the core of BGS science
strategy and delivery; a full project list is given in the Appendix.
9. BGS evidence, addressing each point raised
by the Committee, will concentrate on underground CO2 storage.
THE VIABILITY
OF CCS AS
A CARBON
ABATEMENT TECHNOLOGY
FOR THE
UK
THE CURRENT
STATE OF
R&D IN, AND
DEPLOYMENT OF,
CCS TECHNOLOGIES
10. Research on underground storage focuses
on improving storage capacity estimates and on developing technologies
to monitor CO2 both in the deep subsurface (in and around the
storage reservoir), and also at the near-surface (should leakage
ultimately occur). It is likely that for future large-scale implementation,
a typical storage site will need to assess the risks of CO2 storage
to both humans and ecosystems over 5,000-10,000 year timescales.
This will require careful, systematic, wide-ranging, transparent
and auditable risk assessments, which demand an understanding
of the processes that could affect site performance. Reservoir
simulators, geochemical, and geomechanical models are used to
predict these processes and their interactions, combining detailed
site-specific geological models with generic data derived from
studies of industrial-scale demonstrations, laboratory- and field-scale
experiments, and natural analogues. Simulators and models for
CO2 behaviour are still in their infancy. More field trials at
laboratory and industrial scale are needed to history-match and
refine these tools. This will enable confidence with forward modelling
and long term performance prediction. Also needed are a wider
array of monitoring technologies with improved resolution and
sensitivity. Tool testing, monitoring and verification at field-scale
across the spectrum of geology, site conditions and ecosystems
that could apply to storage operations is required.
CO2 injection demonstrations and tests
11. Although there are numerous CO2 injection
operations associated with onshore-enhanced oil production (EOR;
not CO2 storage) in North America and, to a lesser extent, in
Eastern Europe, few have been accessible to researchers. Projects
in which the broad research community is involved include; Sleipner
(Norwegian North Sea) where nearly 1Mt/year has been injected
since 1996 into an aquifer; and an EOR project at the Weyburn
oilfield (Canada) where over 2mt have been injected since 2000. In
2004, CO2 injection into an aquifer started at InSalah, Algeria.
Similar projects are also planned for Norway (2006), Australia
(c 2009). Small-scale field laboratory aquifer storage pilots
(<100Kt CO2) have recently been conducted in Japan, and the
USA. Further small pilots are planned in Australia, Canada, France,
Germany and the USA. A pilot injection into a coal seam has recently
been completed in Poland. In the Netherlands, a small pilot is
injecting into an offshore gas field (K12b). The UK may have its
first large-scale injection at the Miller Field, by 2009 (subject
to commercial decisions by BP and its partners). Miller could
become the first offshore CO2 EOR project in the world.
12. Despite having very different reservoir
properties and conditions, Sleipner and Weyburn have demonstrated
that large-scale CO2 injection is feasible. Monitoring operations
at both sites show that the CO2 plumes in the reservoir can be
satisfactorily imaged using repeated 3D seismic techniques (similar
to echo-sounding) and indicate that, at least in the short-term,
site behaviour can be predicted with reasonable confidence. No
leakage has been detected. Extending predictions into the longer-term
and, in particular, well beyond the monitoring phase is more challenging
and needs further research.
PROJECTED TIMESCALES
FOR PRODUCING
MARKET-READY,
SCALABLE TECHNOLOGIES
13. It is technically feasible to deploy
CCS at industrial scales now. Sleipner and Weyburn are examples
where fiscal and regulatory regimes and technologies are in place
with CCS operating commercially. CCS technology is market ready
for pioneering implementation now in the UK. Technology improvement
requires commercial scale projects to work with and learn from.
14. The low risk of leakage, in early projects,
has to be balanced against the global impacts that will ensue
if CCS is not made commercially viable; this is a matter for governments
to address through policy, fiscal and regulatory initiatives.
COSTS
Storage costs
15. There are few published details of storage
costs. They are field specific. Some details are available for
Sleipner (Torpe & Brown 2004), which refer to the incremental
cost of storage only. The capital costs were approximately US$96
million (based on a projected total storage of 25 MtCO2 = US$3.8/tCO2
stored) and the operating costs are approximately US$7 million/year
(7US$/t stored) respectively. Therefore, total storage costs are
about US$11/t (£6/t) CO2 stored.
Monitoring costs
16. Monitoring costs are minor and have
been estimated (Benson et al 2004) at 0.05-0.10US$/t of CO2 stored
(discounted at 10% per year), 0.16-0.31US$/t of CO2 stored undiscounted,
2.7-5.4p and 8.7-17p per tonne CO2 respectively.
Enhanced Oil Recovery
17. In many oil field conditions, CO2 is
miscible with oil and can be injected to enhance oil recovery
(EOR). There are over 70 CO2 EOR projects in North America. CO2
storage is a passive bi-product of these operations. Offshore
EOR using CO2 has not yet been deployed and costs and risks would
be higher. Economic viability is field specific, dependent on
the oil price, supply of CO2, re-engineering costs of existing
infrastructure and tax regime. Costs will be higher offshore because
of the larger capital and operational investment needed.
GEOPHYSICAL FEASIBILITY
18. Geophysical techniques are feasible
for CO2 monitoring and verification, as part of a technology portfolio
including geochemical, remote sensing and biological monitoring
techniques that include invasive and non-invasive deployment.
There is a need to improve sensitivity and resolution as well
as discover limitations and appropriateness. Some technologies
will apply to all sites; others will be site specific.
OTHER OBSTACLES
OR CONSTRAINTS
19. Major issues connected with large-scale
deployment of CCS in the UK include, large initial capital investment,
ultimate useable storage capacity, possible environmental impacts
and regulation.
Storage capacity
20. Many of the deep reservoir rocks (porous
rock formations) of the UK are suitable for the large-scale underground
storage of CO2. There are opportunities for CO2 storage in
hydrocarbon fields (producing and depleted), other saline water-bearing
reservoirs (saline aquifers) and possibly, to a minor extent,
in coal seams. Storage potential lies mainly offshore beneath
the UK continental shelf, although niche opportunities may exist
onshore.
Storage in oil and gas fields
21. Hydrocarbon fields have entrapped buoyant
fluids for periods up to millions of years. Because of exploration
and production activity, they are geologically well characterized
and their reservoir properties are well understood. The main risk
issue with CO2 storage in hydrocarbon fields is the possibility
that CO2 may eventually leak upwards along pre-existing exploration
and production wells.
22. The CO2 storage capacity of UK hydrocarbon
fields can be assessed with reasonable accuracy because the field
data is in the public domain. However, not all of the theoretical
storage potential could necessarily be exploited economically.
23. Provisional figures are as follows for
the UK (excluding gas and condensate fields for the central and
northern North Sea which have yet to be calculated):
— Oil and gas fields of the East Irish
Sea (between the Isle of Man and Lancashire and North Wales coasts):
1Gt of CO2 (Kirk in press)
— Gas fields of the South North Sea
(between the straits of Dover and Newcastle upon Tyne): 3Gt of
CO2 (Bentham in press, Holloway et al in press)
— Oil fields of the Northern and Central
North Sea: 0.7Gt of CO2 (Balbinski 2001)
24. With the exception of Wytch Farm, onshore
fields are too small for significant CO2 storage. However, some
could be suitable for testing or feasibility trials.
25. Reservoir simulation is required to
make more accurate storage calculations on a field-by-field basis,
particularly of the amount of CO2 that could be stored by EOR.
This is a function of geology and individual field economics and
will be investigated by the UK Carbon Capture and Storage Consortium
(UKCCSC) over the next three years.
Storage in saline aquifers
26. The CO2 storage capacity of the UK deep
saline aquifers is more uncertain than that for hydrocarbon fields,
and should be the subject of major further research. Aquifer storage
likely represents the bulk of the available UK storage capacity
(possibly, together with Norway, the largest capacity in Western
Europe), but there is no standard methodology for calculating
it from the sparse public domain data available. BGS has provisionally
estimated the CO2 storage capacity of saline water-bearing reservoir
rocks in closed structures around the UK as follows:
— East Irish Sea Basin: up to 0.63Gt
of CO2 (Kirk 2005)
— Southern North Sea Basin: up to14.25
Gt of CO2 (Brook et al 2003, Holloway et al in press)
27. No recent estimate has been made for
the Central and Northern North Sea basins or other parts of the
UK Continental Shelf such as the English Channel Basin. An estimate
of 250Gt was calculated in the BGS led Joule 2 (1995) Project
for all the aquifers (open and closed) in the UK North Sea. With
UK emissions at over 0.6Gt/year, a third of which comes from power
generation it is clear that even if only 10% of this capacity
was realized it would serve the UK's needs to beyond the period
of fossil fuel dependency.
Knowledge of potential impacts
28. The generic knowledge that underpins
our ability to make long-term predictive risk assessments is far
from complete and many issues are, as yet, poorly understood (West
et al 2005). A particular challenge is to assess the localised
impacts of CO2 leakage on ecosystems. One way is to study natural
accumulations of CO2 where this has remained underground for thousands
to millions of years or, in some cases, reached the surface.
29. Industrial demonstration projects associated
with hydrocarbon production are unlikely to leak during operational
life, and any short-term, transient leak would be remediated as
part of routine operations. These projects are generally not appropriate
to develop and test the models used in risk assessment to predict
leaks and their impacts. Short-term but well-constrained deliberate
release laboratory and field experiments, and longer-term but
less well constrained natural analogues can provide ideal opportunities
to assess our ability to demonstrate long-term safety and risk.
Well performance
30. Another key issue for long-term safety
is the ability of wells to retain their sealing integrity. CO2,
in the presence of moisture, can attack the cements and metals
used in well completions. While modern wells are designed to minimise
these problems, pre-existing wells will have used traditional
completion materials. If the well integrity fails, then it could
provide a route for the buoyant CO2 to escape.
Regulation
31. Unlike North America, the UK does not
have a history of gas disposal via wells. In the USA there are
over 400 acid gas injection operations into deep saline aquifers,
all carried out under EPA jurisdiction. Appropriate regulation
for CO2 storage is not in place here, outside hydrocarbon production
and related operations. Underground natural gas and hydrogen storage
is conducted in the UK within a regulatory framework.
32. Regulations for storage may be needed
to avoid conflicts of interest between CCS and other activities,
both underground (mining, hydrocarbons, groundwater) and at the
surface (land use, ecosystem and public protection).
33. The IPCC and the European Emission Trading
Scheme (ETS) are both evaluating how CCS may be regulated in order
that avoided CO2 emissions are counted in national allocations
and recognized within carbon trading regulations.
34. Considerable uncertainty remains over
environmental regulation and CCS. Members of the OSPAR and London
Conventions are considering this. Current legislation is being
examined at the European (DG Environment) and UK (DTI/Defra/EA)
levels to see how it might interact with CCS activities and if
there is a need to develop additional regulation.
35. As part of its recent Technology Status
Review (TSR) for the DTI (Report URN05/103), the BGS suggested
some regulatory models for consideration during the lifecycle
of a CO2 storage operation.
THE UK GOVERNMENT'S
ROLE IN
FUNDING CCS R&D AND
PROVIDING INCENTIVES
FOR TECHNOLOGY
TRANSFER AND
INDUSTRIAL R&D IN
CCS TECHNOLOGY
On average DTI has invested c £50k/year
in BGS-driven CO2 storage research over the last 10 years. This
has been to support BGS involvement in EC Framework Projects
Other DTI expenditure (costs not known to BGS).
DTI is supporting Heriott Watt University as
part of a project to examine the feasibility of CO2 storage in
scottish coals. This project is also receiving support from the
Scottish Executive.
A budget of £20 million has been allocated
to DTI for the period 2005-08, with a further £40 million
from 2006-10 to fund CATs. It is not yet decided how much of this
will be apportioned to R&D in CCS (the CAT programme also
includes hydrogen, fuel cells, biomass co-firing and power plant
efficiency R&D).
UK Research Council funding on CCS
— TSEC, NERC, ESRC and EPSRC are currently
supporting the UK Carbon Capture and Storage Consortium through
their TSEC programme (BGS is a participant). This Consortium (http://www.co2storage.org.uk/)
is undertaking a CCS project that will run from July 2005-June
2008. Funding is approximately £2 million spread amongst
14 UK institutes and universities.
— Tyndall Centre. BGS received £55K
between FY2002/3-5/6 from the centre's "Decarbonising Society"
Thematic Programme to support its research into CO2 storage. BGS
does not know how much of the Centre's resources apply to CCS.
— UKERC- BGS is expected to receive
£112k from 2005-10 from UKERC to support its "Carbon
Management" sub-theme. BGS does not know how much of UKERC's
overall budget applies to CCS.
— BGS (NERC) BGS has been investing
an average of £350k (FEC) per year of its own Science Budget
in CCS research since FY2000-1. This has risen to over £500K
(FEC) this year. Future investment at this level is uncertain
because of NERC's financial settlement in SR2004. The bulk of
BGS' spend is to align with, and co-ordinate, CO2GeoNet.
— EPSRC grants for CCS amount to £103k
for FY05-06.
Other UK Government Investment in CCS
In 2005 Heriott Watt and Edinburgh University
were awarded £1.4 million over four years to form the "Scottish
Centre for Carbon Management". BGS is collaborating at its
own cost.
September 2005
Annex
LIST OF CURRENT AND PLANNED EUROPEAN CCS
PROJECTS WITH BGS INVOLVEMENT
JOULE II The first, pioneering feasibility study
of CO2 storage, partly funded by EC FP4 JouleII Programme and
coordinated by the BGS.
GESTCO A preliminary estimate of the storage
capacities of some European member states was made and a decision
support tool created to match sources to storage sites and provide
rough cost estimates. [http://www.nitg.tno.nl/projects/eurogeosurveys/projects/GestcoWeb/]
NASCENT A study of European natural occurrences
of CO2, that provided information on the long-term process associated
with CO2 storage and allowed some predictive models to be preliminarily
tested with analogue systems [http://www.bgs.ac.uk/nascent/]
Weyburn 1 BGS co-ordinated the European research
effort into Weryburn phase 1 CO2 monitoring. The final report
can be fund at www.ptrc.ca
CARNOT—grean energy form coal; study of
potential siting of integrated gasification combined cycle power/hydrogen
plant fitted with CO2 capture in the UK. This was carried out
with Progressive Energy.
NGCAS: Study investigating possible storage
options for refinery and gas processing facilities in Scotland.
CO2NET A European thematic network that brings
together industrial and academic organisations from both capture
and storage areas to provide advice to other stakeholders. [http://www.co2net.com]
SACS/SACS2 The first and second phases of research
centred on the Sleipner injection. [http://www.iku.sintef.no/projects/IK23430000/News/index.html
CO2STORE Techniques developed and continued
within the SACS projects are applied to three more planned small
injection sites in Europe, including more detailed assessments
of long-term risks. [http://www.co2store.org/]
CASTOR Focussing primarily on capture technologies
but also including continued development of monitoring techniques
and investigations of long-term processes. [http://195.167.229.95/QuickPlace/castor/Main.nsf/h-Index/C7F9D7B939137AB400256EC40049C019/?OpenDocument&Form=h-PrintUI]
CO2GeoNet is an EC FP6 Network of Excellence
that brings together 13 organisations investigating various aspects
of CO2 storage to develop common methodologies, collaborative
research programmes and ultimately closer integration. [http://www.co2geonet.com/]
The UK Carbon Capture and Storage Consortium
(UKCCSC) is a new research council funded collaborative project
that will evaluate the role of CCS in the UK as well as some of
the barriers to implementation, within the TSEC http://www.co2storage.org.uk
CO2ReMoVe A new FP6 project focussing on developing
techniques to monitor and verify CO2 storage projects to make
them eligible within the European emission Trading Scheme.
Dynamis. A new FP6 project investigating the
feasibility of large scale power generation from Hydrogen derived
from fossil fuels.
In CACO2- An EC funded Special Action to horizon-scan
international developments in CCS outside the EU. Comprises oil
and gas industry, power utilities and R&D organisations and
represent these stakeholders at the US led CSLF.
EXAMPLES OF
PUBLIC SECTOR
FUNDING OF
CCS R&D IN OTHER
COUNTRIES
USA—US Department of Energy has committed
over $180 million of investment into CCS RD&D since 1998,
with $107.5 million of that announced this year spread over the
next four years.
Australia—CO2CRC receives commonwealth
funds of circa A$24 million (2003-10), with an additional A$111.21
million of public sector support, of which A$14.607 million is
from Geoscience Australia (Australia's national geological survey).
CO2CRC is not the only public funded CCS research being conducted
in Australia.
Norway—The Klimatek programme invested
over NoK300 million between 1992-2000. Since 2002 funding
has been circa NoK50 million/y. In 2005 "GASSNOVA" was
set up which will fund CCS RD&D at a rate of NoK150 million/y
for the foreseeable future.
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