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NBS-3B1Y - Strategic Corporate Sustainability
10th December 2014
FrackingA solution to the UK Energy
Problemsor
An unacceptable step too far?Keith Tovey ( 杜伟贤 ) : MA, PhD, CEng, MICE, CEnv
Reader Emeritus in Environmental Science, University of East Anglia
Recipient of James Watt Gold Medal 1
FRACKING
Definitions• “ a method of mining in which cracks are created in
subteranean rocks to obtain gas, oil, or other liquids”.• Hydraulic Fracturing using high pressure liquids is
usual way of creating cracks• Fracking is the slang term for Hydraulic Fracturing
Tonight’s Talk• What is Fracking? Physical Resource and Definitions• Fracking – technical issues and examples • Impact of Fracking on UK Energy Supply • Where have conventional/unconventional wells been
drilled in UK & Economic Issues• Fracking – Environmental Impacts [seismic etc]• Summary and other issues
2
Fracking: Some Definitions
•Unconventional Gas: •Tight Gas: -found in relatively low permeability rocks such as sandstones and limestone. Some fracturing may be needed to enhance extraction
3
• Conventional Gas: - predominantly methane with other hydrocarbons, carbon dioxide, nitrogen, hydrogen sulphide etc,
Found trapped in relatively porous media capped by an impermeable stratum. Gas migrates upwards to a capped area.
• Shale Gas: - found in ultra low permeability shales. Extensive hydro fracturing needed to extract gas
Sandstone
Schematic geology of natural gas resources
Land Surface
Coal Bed Methane
Tight Sand Gas
oil
Conventional Associated
Gas
Seal
Diagram based on US Energy Information Administration
Gas rich Shale
Conventional Non-associated Gas
4
Fracking: Some Definitions• Dry Gas: - predominantly methane with little if any co-
products such as ethane, propane etc.
• Wet Gas: contains appreciable proportions co-products of hydrocarbon such as ethane, propane, and butane which may be in liquid or gaseous form.
• Co-products may be liquefied as LPG or converted into petrol and add value to gas produced.
• WET GAS is defined as having more than 0.1 US gal of condensate per 1000 cuft.
• Reserve: Total Amount of gas in Reservoir: Three figures: Proven, Probable, Possible
• Resource: Amount of gas which can Technically and/or Economically be extracted - typically 10-20% of Reserve
5
Where Shales are located in UK
6
Biological decay of organic at shallow depthsBiogenic methane
Organic matter “cooked” at depth and pressure Thermogenic methane in Shale
Biogenic and Thermogenic methane can be distinguished by isotopic means
Typical Fracking Installations
• A single Fracking Well in Pennsylvania
7
Large ponds (0.5 – 1ha) are needed to hold Flowback Water.
Aquifer
Horizontal Drilling
Hydraulic Fracturing
Shale
Drilling through Aquifer & Rock Layers
Borehole
Schematic of a Shale Gas Well
9
Aquifer
Cemented Steel Casing
Shale Formation
Cement pumped through borehole to surround casing
High pressure fluid mixture creates numerous paper-thin fractures
throughout shale.
Small fractures free trapped gas which flows into perforated
casing and up to surface.
Schematic of a Shale Gas Well
10
Fracturing fluids contain ~ 94% water, 5% sand and up to 1% of additives such as ACID, SCALE INHIBITORS, BIOCIDES, FRICTION REDUCERS AND SURFACTANTS.
Fluid is injected under pressure to stimulate cracking of the Shale. The sand props the cracks open to promote gas flow.
Diagrams based on Tyndall Report (2011b) and Royal Society Report (2012)
Fracking in a Horizontal Well
11
The casing has multiple annual rings some which can slide longitudinally to open valves for fracking.
Well and Pad Configurations
12
Cuadrilla are proposing up to 10 wells per Pad
In US, typically up to 6 wells per Pad
Pad
1 – 2km
Output from a Single Shale Gas Well
Output declines by 95% over first 3-4 yearsTotal output over 20 years is equivalent to two 3 MW wind turbines 13
Estimated Gas Production: Cuadrilla Scenarios for Bowland-Hodder Shale (2014–2040)
Low Medium High
Cumulative Production (bcm) 19.7 40.3 76.7
Wells 190 400 810
Well Pads 19 40 81
Average annual production (bcm) 0.73 1.49 2.84
Average annual production as a percentage of UK consumption (91bcm)
0.8% 1.7% 3.2%
Water volume (m3) 1,679,800 3,359,600 6,719,200
Flowback Water (m3) – for treatment 785,838 1,571,675 3,143,350
Truck Visits 181,750 363,500 720,000
Average Truck Visits per weekday 26 53 106
Production in single year (bcm) 0.29 -2.12 0.58 -3.57 0.58 -4.90
From Tables 2.13 – 2.14 of Tyndall (2011b) Report
Maximum Cumulative Production from Blackpool Area over the 25 years would be ~76 bcm or 10 months current UK supply
Average household consumption of water ~ 180 m3/year
14
Gas Production and demand in UK
15
Import Gap
Impact of temporary switch to coal generation
Gas supply has become critical at times – e.g. at end of March 2013 – down to 6 hours supply following technical problems on Norwegian Pipeline.
Rakteem Katakey: (Bloomberg Press) –
The Ukrainian crisis is poised to reshape the politics of oil by accelerating Russia’s drive to send more barrels to China, leaving Europe with pricier imports and boosting U.S. dependence on fuel from the Middle East.
China already has agreed to buy more than $350 billion of Russian crude in coming years.
Such shifts will be hard to overcome: Europe, which gets about 30 percent of its natural gas from Russia, has few viable immediate alternatives. The U.S, even after the shale boom, must import 40 percent of its crude oil, 10.6 million barrels a day that leaves the country vulnerable to global markets.
Impact of Ukraine Crisis
16
Based on Figure 3.1 in Tyndall (2011b) Report
The most optimistic scenario data from above are used Electricity Scenario assumes •similar split of gas use for electricity / non-electricity demand•5% improvement in efficiency for CCGT generation plant•Maximum generation from Fracked gas = ~36.5 TWh by 2030
Estimates of Total UK Production of Fracked Gas
17
Assumptions in Electricity Scenarios
Assume Highest Projection for Fracked Gas
Future Demand – Climate Change Committee (2011) estimates• Assumes significant growth in electricity for electric vehicles
and heat pumps• Alternative demand – limited growth in electric vehicles and
heat pumps.
Fossil Fuel/Nuclear Generation• Existing Nuclear / Coal Stations close as published
09/09/2013• New Nuclear completions at one reactor per year from 2021.• New Coal with CCS as demonstration schemes @ 300 MW per
annum from 2020 & 1000 MW per annum from late 2020s• Gas including Fracked Gas will cover any shortfall between
DEMAND and COAL + NUCLEAR + RENEWABLE GENERATION 18
Impact of Fracked Gas on Electricity Generation up to 2030
Renewable Electricity Generation Futures[Load Factors based on weighted averages over last 5
years]
Wind
Other Renewables: Solar, Marine, Biomass, Hydro• Solar installation rate increases to 1 million houses a
year from 2020 – 40% houses fitted by 2030• Tidal and Wave – up to 2 GW by 2020 and significant
expansion thereafter with Severn Barrage completed by 2025 19
Impact of Fracked Gas on Electricity Generation up to 2030
Wholesale prices are over 2.5 times what they were in 2004Domestic Prices have risen by ~ 100% over periodLess than10% of rise can be attributed to support for renewables
Cost of Energy
20
UK no longer self sufficient
in gas
UK Government Projection in 2003 for 2020
Oil reaches $130 a barrel
Langeled Line to Norway
Severe Cold Spells
wholesale prices updated to 16th September 2014
21
Our looming over-dependence on gas for electricity generation
Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030.
Existing Coal
Existing Nuclear
Oil
Data for modelling derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030.
0
100
200
300
400
500
600
1970 1980 1990 2000 2010 2020 2030
TW
H (b
illio
ns o
f uni
ts (k
Wh)
)
Existing Coal
UK GasImported Gas
New Nuclear?
New Coal ?
Existing Nuclear
Other Renewables
Offshore WindOnshore Wind
Oil
Data for demand derived from DECC & Climate Change Committee (2011) - allowing for significant deployment of electric vehicles and heat pumps by 2030.
• Limited electric cars or heat pumps
Version suitable for Office 2007 & 2010
Fracked Gas
Fracking: Economic Issues
• Viability of a Shale Gas Well – defined by EUR (Economic Ultimate Recovery).
• According to recent research (Bloomberg Feb 2013) • “the cost of shale gas extraction in the UK is likely to
be significantly higher than in the US”.• Cost of gas produced is reduced if high value co-
products are present in “WET” gas. [Many (most?) wells in US are WET ].
This advantage is unlikely to be significant in UK where much of gas is likely to be “DRY”.
Comments such as: "We will continue to drill to hold leases, and will
continue to drill in the wet gas. But there will be little if any drilling in the dry gas areas“
are becoming increasingly common in US.
22
Fracking: Economic Issues• Claims are made that Fracking will reduce cost of gas
in UK - Evidence often cited from US.• BUT nowhere has the price of exactly how much
Fracked Gas will cost been indicated.• How can claims be made that it will be cheaper if this
information in is not forthcoming?• Even with most optimistic scenarios, Fracked Gas will
NOT be significant until after 2030.• Over concentration on Fracking is diverting attention
from the pressing issues of the Capacity Gap looming post 2015
23
11 th May 2014: Financial Times:
$1tn of new oil and gas projects ‘uneconomic’
“The cost of developing many new oil and gas assets
is well over $100 per barrel”.
“In the current environment many projects do not
make sense from a cost perspective.”
Fracking: Carbon Emissions
24
Climate Change issuesFugitive emissions from shale gas exploitation will be higher than conventional gas extraction.Direct use of gas
• conventional - 199 – 207 g/kWh*
• fracked gas - 200 – 253 g/kWh* depending on regulationElectricity generation
• Conventional gas using CCGT ~ 360 – 430 g/kWh• Shale gas using CCGT ~ 423 – 535 g/kWh *
• Coal ~ 837 – 1130g/kWh *
• Fracked gas would help in decarbonising electricity supply in comparison to coal.
• BUT coal use in generation is set to decline significantly. • Fracked gas is worse than conventional gas and much
worse than nuclear or renewables and increase in gas use would jeopardize decarbonisation of Energy Supply.
* Data from Mackay& Stone (DECC 9th September 2013).
Fracking: Seismic Issues• Richter scale (ML) is a logarithmic scale• An increase by 1 indicates an energy increase of 10 times • Suggested UK Threshold level for reporting Fracking - 0.5
– i.e. ground movement associated with traffic. Some say threshold should be 1.0
• Fracking induced events in Lancashire caused earthquakes of magnitude 1.5 and 2.3 or 10 and 64 times the energy of the threshold
• Christchurch earthquake was 640 thousand times larger• Fukushima earthquake was 400 million times larger• Threshold of 0.5 at depth would not be perceptible: 10 – 12
traffic incidents a day might trigger this limit.• Consequences of Lancashire incidents
– Small events up to 0.5 occurred during Fracking. The 1.5 & 2.3 events occurred 10 hours after Fracking ceased - below level of the occasional earthquake in UK.
– [some damage reported at base of well, but no damage to casing through aquifer]. 25
Perception of Seismic Events
Magnitude UK frequency Impact at surface
1.0 100s per year Not felt, except by a very few under especiallyfavourable conditions.
2.0 ~ 25 per year Not felt, except by a very few under especiallyfavourable conditions.
3.0 ~ 3 per year Felt by few people at rest or in the upper floors of buildings; similar to the passing of a heavy truck.
4.0 ~ 1 every 3–4 years
Felt by many people, often up to tens of kilometres away; some dishes broken; pendulum clocks may stop.
5.0 1 every 20+ years
Felt by all people nearby; damage negligible in buildings of good design and construction; few instances of fallen plaster; some chimneys broken.
26
Seismic effects of Fracking usually have magnitude ~ 0.5 to 1.0. One Lancashire event reached 2.3
Incidence of Earthquakes in UK 1382 – 2012
Red dots – NaturalBlue dots – coal mining
Historic Seismicity in UK
>54 – 53 - 42 – 3<2
Magnitude
Royal Society Report (2012)27
Methane Contamination of Groundwater
The dramatic videos on You-Tube of tap water igniting were claimed to be caused by Fracking. Naturally occurring biogenic methane was the cause in most cases, and not FRACKING.
These are Peer Reviewed Journals
28
Distribution of Fracking Wells in Dallas – Fort Worth Area
Impact of Large Scale Development of Fracking
If US model is followed
UK may require several tens of thousands of wells to make a substantial contribution to Energy Supply.
29
Aftermath of extensive drilling in Wyoming
30
Summary of Key Issues (1)
• There are significant Reserves of Shale Gas in UK
But do not confuse Reserves with Resource
• Most optimistic Resource extraction would potentially provide between 7.5 & 10% of electricity generation by 2030, although could be 2 – 2.5 times that figure by 2050
But there are more important issues in Energy Security, Climate Change and Affordability to address post 2015
• Developers are evasive in giving an actual maximum cost per GWh gas produced. Unless this is no more than current wholesale price, Statements such as
“Fracking will result in cheaper Gas”
cannot be justified and are extremely misleading.
• Output from a single well drops by 80+% in first 2 years of operation. Large scale extraction in UK could lead to tens of thousands of wells in UK.
31
Summary of Key Issues (2)• Seismic Risk is very small indeed• Contamination of ground water by methane / other chemicals
might occur in a well failure or spillage for surface facilities.• Over dramatic videos of ignition of water from taps are
misleading as these are often of biogenic methane• Adequate Regulation needed, but this will increase costs.• Large quantities of water are needed • Sand and Additives (some of which are toxins) are added.• Flowback Fluid ~ 50% of injected fluids contains
contaminants as above and naturally occurring chemicals and naturally occurring Radioactive Material (NORM).
32
In Summary• Fracking could marginally help to improve Energy Security in
UK• Questionable whether it would in fact be cheaper than at
present• Climate Change Targets would be jeopardized if there were a
consequential shift from Renewables and Nuclear
33
The following slides were not used in the actual presentation, but have been in previous versions
34
Imported Gas: Where does the UK gas come from?
35
Exports go primarily to Belgium and Ireland
Gas is traded on the international Market and prices have become significantly more volatile since UK became a net importer.
Differences between Sandstone and Shale
Sandstone Shale
Large PoresMicroscopic Pores
From British Geological Survey Presentation 36
Yellow dots show locations where gas has flowed
Location of Wells drilled for Gas and Oil.
37
Sources of information• DECC (2012) Shale Gas Briefing Notehttps://www.gov.uk/government/uploads/system/uploads/attachment_data/file/48332/5057-background-note-on-shale-gas-and-hydraulic-fractur.pdf• DECC (2013) About shale gas and hydraulic fracturing (fracking)https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/226040/About_Shale_gas_and_hydraulic_fracking.pdf• EIA (2013) Annual Energy Outlook 2013 http://www.eia.gov/forecasts/aeo/• Mackay DJC & Stone J (2013) Potential Greenhouse Gas Emissions Associated with Shale Gas
Extraction and Use. DECC https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/237330/
MacKay_Stone_shale_study_report_09092013.pdf• Royal Society (2012). Shale Gas Extraction in the UK
http://royalsociety.org/policy/projects/shale-gas-extraction• Smith, N.; Turner, P.; Williams, G.. 2010 UK data and analysis for shale gas prospectivity. In:
Vining, B.A.; Pickering, S.C., (eds.) Petroleum Geology : From Mature Basins to New Frontiers : Proceedings of the 7th Petroleum Geology Conference. Geological Society of London, 1087-1098. (see also
http://nora.nerc.ac.uk/13090/)• Tyndall (2011a). Shale gas: a provisional assessment of climate change and environmental
impacts.http://www.tyndall.ac.uk/sites/default/files/coop_shale_gas_report_final_200111.pdf• Tyndall (2011b). Shale gas: an updated assessment of environmental and climate change
impacts http://www.cooperative.coop/Corporate/Fracking/Shale%20gas%20update%20-%20full
%20report.pdf• UKOOG (2013) Community Engagement Charter: Oil and Gas from Unconventional Reservoirs https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/225851/
Publication_UKOOG_communityengagementcharterversion6.pdf• Osborn, SG, A Vengosh, NR Warner, RB Jackson. (2011). Methane contamination of drinking
water accompanying gas-well drilling and hydraulic fracturing. Proceedings of the National Academy of Sciences, U.S.A. 108:8172-8176, dx.doi.org/10.1073/pnas.1100682108.
• Molofsky, LJ, Connor, JA, Albert S. Wylie, AS Tom Wagner, T & Farhat, SK (2013) Evaluation of Methane Sources in Groundwater in Northeastern Pennsylvania Vol. 51, No. 3–Groundwater: 51 (no 3): 333–349 DOI: 10.1111/gwat.12056
http://onlinelibrary.wiley.com/doi/10.1111/gwat.12056/abstract38
