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Fracking: How cheap energy is reshaping America’s environment
Jared Atkinson, MIT Natasha Goss, Harvard
Jordan Wilkerson, Harvard
Controversy
My Background
A note on semantics…
“Unconventional”
Shale gas Shale oil Tar sands
Methane hydrates
A note on semantics…
“Unconventional”
Shale gas Shale oil Tar sands
Methane hydrates
Roadmap for the evening
1. Hydraulic Fracturing: How…and Why?
2. Water Contamination and Induced Seismicity
3. Impact of Fracking on Climate Structure
Roadmap for the evening
1. Hydraulic Fracturing: How…and Why?
2. Water Contamination and Induced Seismicity
3. Impact of Fracking on Climate Structure
Hydraulic Fracturing: How…and Why?
1. Hydrocarbon basics
2. The F-word
3. Why are we doing this?
Hydraulic Fracturing: How…and Why?
1. Hydrocarbon basics
2. The F-word
3. Why are we doing this?
What is…
Hydrocarbon? • An organic compound consisting of carbon
and hydrogen
Adaproject.org
plastic ties row cover irrigation piping polyethylene polypropylene bags and packaging pesticides and herbicides food preservatives fertilizers ballet tights nylon cord polyester everything permanent press beads bracelets pantyhose nylon zippers plastic hangers purses thongs and flip flops earrings ribbons fake fur windbreakers sandals garment bags shoe laces rain coats iron-on patches sneakers sweaters sofa pillow material• tote bags umbrellas ball point pens diskettes thermometer Ink computers business card holders copiers waste baskets calculators printer cartridges microfilm name tags binders erasers
cameras beach balls fishing poles hang gliders vinyl cases footballs glue containers puzzles darts Frisbees golf ball and golf bags shotgun shells ear plugs knitting needles• waterproof clothing stadium cushions earphones yarn kites tennis racquets fabric dye decoys lifejackets nylon strings face protectors volley balls model cars plastic water guns fishing bobbers soccer balls oil paints parachutes fishing cylume light sticks earphones playing cards photographs monofilament fishing lines diving boards poker chips goggles rollerskate and skateboard wheels whistles guitar strings picks rafts ice chests tents
plastic flowerpots hot tub covers sails snorkels• monkey bars photo albums wet suits flippers tennis balls boats insulated boots acrylic toys baby oil laundry baskets waterproof pants baby aspirin bath soap mittens pacifiers baby blankets bibs rattles doubleknit shirts baby bottles disposable diapers baby shoes teething rings nipples and binkies dolls stuffed animals baby lotion allergy medication cotton-tipped swabs inhalers liquid Pepto-Bismol aspirin first aid cream lancets pill cases band aids first aid kits• latex gloves prescription bottles burn lotion glycerin mosquito spray rubbing alcohol chap stick heart valve replacement nasal decongestant surgical tape syringes Vaseline antiseptics
hearing aids anesthetics artificial limbs eyeglasses and sunglasses antihistamines cortisone vaporizers denture adhesives laxatives Bactine oxygen masks stethoscopes prescription glasses cough syrup hearing aids vinegar bottles egg cartons meat trays trash bags breadboxes freezer containers melamine dishware tumblers cake decorations jars microwave dishes utensils candles freezer bags milk jugs vacuum bottles coasters gelatin molds nylon spatulas wax paper coffee pots ice cream scoops oven bags mops drinking cups ice trays plastic containers fabric softener detergent bottles plastic table service drain stoppers dish drainers lunch boxes pudding molds sponges dish scrubber
baggies drinking straws Styrofoam paper cup dispenser measuring cups Teflon coated pans table cloths refrigerator shelves cologne hair brushes lipstick permanent wave curlers perfume hair color mascara• petroleum jelly comb foam rubber curlers shampoo contact lenses and cases hair spray hand lotion shaving foam hair dryers shoe inserts dentures body lotion face masks skin cleanser deodorants moisturizing cream soap holders disposable razors leather conditioner mouthwash sunglasses facial toner lens cleanser nail polish sunscreen tooth brushes toothpaste tubes vitamins synthetic wigs bubble bath soap capsules carpet padding Naugahyde Venetian blinds TV cabinets extension cords picture frames
shower doors Formica• refrigerator lining vinyl wallpaper curtains kitchen carpet shag carpet welcome mats fan blades lamps shower curtain patio furniture swings linoleum upholstery rugs caulking material light switch plates plungers faucet washers clotheslines measuring tape polyurethane stain water pipes electric saws paintbrushes propane bottles wood floor cleaner/wax vinyl electrical tape plastic pipe shingles (asphalt) light panels garden hoses plastic wood spackling paste awnings glazing compound Plexiglas spray paint enamel epoxy paint artificial turf folding doors• floor wax glue house paint paint rollers toilet seats water pipes putty solvents roofing material plywood adhesive sockets propane
antifreeze flat tire fix street paving (asphalt) car battery cases coolant motor oil tires loud speakers bearing grease sports car bodies traffic cones car enamel brake fluid dashboards windshield wipers visors car sound insulation oil filters car seats convertible tops fan belts gasoline ash trays dog food dishes toolboxes• CDs and DVDs balloons dog leashes tape recorders synthetic rubber bubble gum dog toys flashlights nylon ropes bungee straps flight bags disposable lighters cassette player flea collars flutes lighter fluid cigarette cases electric blankets tool racks name tags
Illinois Oil and Gas Association
What is…
Hydraulic Fracturing? • AKA “Fracking”
• The fracturing of rock by pressurized liquid
• Well “stimulation” technique that enhances permeability
Grain
Permeability Porosity
Porosity vs. Permeability
Pore
Pore Pore
Porosity Permeability
Grain
What is… Cheap energy?
0"
20"
40"
60"
80"
100"
120"
1993" 1995" 1998" 2001" 2004" 2006" 2009" 2012" 2014"
US#Do
llar#
Year#
Crude"Oil"
Data from U.S. Energy Information Administration
0"
20"
40"
60"
80"
100"
120"
1993" 1995" 1998" 2001" 2004" 2006" 2009" 2012" 2014"
US#Do
llar#
Year#
Crude"Oil"
Coal""
What is… Cheap energy?
Data from U.S. Energy Information Administration
0"
20"
40"
60"
80"
100"
120"
1993" 1995" 1998" 2001" 2004" 2006" 2009" 2012" 2014"
US#Do
llar#
Year#
Natural"Gas"
Crude"Oil"
Coal""
What is… Cheap energy?
Data from U.S. Energy Information Administration
Hydrocarbon Basics
Geology.com
Shale – “Source”
Hydrocarbon Basics
Sandstone – “Reservoir”
Gas
Shale – “Source”
Minimegeology.com
Hydrocarbon Basics: Conventional
Gas
Sandstone
Gas
Shale
Hydrocarbon Basics: Unconventional
Shale
Permeability Porosity
Is Shale Permeable?
Pore
Pore Pore
Porosity Permeability
Grain Grain
Hydrocarbon Basics: ���“Fracking”
Source + Reservoir + Seal
Hydrocarbon Basics: ���“Fracking”
Source + Reservoir + Seal
Fracturing & Permeability
Hydraulic Fracturing: How…and why?
1. Hydrocarbon basics
2. The F-word
3. Why are we doing this?
Hydraulic Fracturing
The F-Word: Frac Facts
5000-10,000 ft
The F-Word: Frac Facts
Length: 100 - 2000 ft Height: 10 – 100 ft
Width: 1/10 in
Questions?
Hydraulic Fracturing: How…and Why?
1. Hydrocarbon basics
2. The F-Word
3. Why are we doing this?
Why?
Modified from: EIA Technically Recoverable Shale Oil and Shale Gas Resources, 2013
Unconventional Resource
Shale Gas (tcf) World Total: 7,299
Unconventional Resource
US: 1,161
Brazil: 245
FSU: 285
Algeria: 707
Australia: 437
China: 1,115
Mexico: 545
Argentina: 802
S Africa: 390
Canada: 573
Why? Demand = Supply
Modified from: EIA Technically Recoverable Shale Oil and Shale Gas Resources, 2013
Why?���Oh Why?
• Inclusion of shale gas increase the US hydrocarbon resources by 38%
• International Energy Agency (IEA) expects US to become energy independent by 2035
• The US could become a net exporter of natural gas
IEA World Energy Outlook, 2013
Hydraulic Fracturing: How…and Why?
• Conventional resources are globally scarce
• Unconventional resources are plentiful • Hydraulic fracturing increases permeability,
allowing production from unconventional rock • Profit and energy independence are primary
motivators
Hydraulic Fracturing: How…and Why?
We know how it’s done We know the motivation What is the impact?
Questions?
Roadmap for the evening
1. Hydraulic Fracturing: How…and Why?
2. Water Contamination and Induced Seismicity
3. Impact of Fracking on Climate Structure
Water Contamination and Induced Seismicity
1. Does fracking cause earthquakes?
2. How much water does fracking use?
3. Does fracking contaminate drinking water?
Ellsworth 2013
Earthquake frequency in the central US has increased since 2001
After 2001: an increasing number of earthquakes peaking at 188 per year in 2011
Before 2001: 21 “significant” US midcontinent quakes per year
Ellsworth 2013
Earthquake frequency in the central US has increased since 2001
Possible causes:
Improved detection?
Human activity, specifically oil/gas extraction?
Not for quakes of this magnitude post-1970
Accounts for at least part of the increase in seismic activity
Fracking causes microtremors, but not large earthquakes
Small rock fractures are routinely produced during hydraulic fracturing, but unless the drilling intersects a fault and causes it to move, they are undetectable at the surface.
Magnitude scale
10-3
1
10-1
10-2
102
101
M=2 (detectable)
Typical force
Ellsworth 2013
Fracking causes microtremors, but not large earthquakes
Largest to date: Horn River Basin, British Columbia (series of small quakes magnitude 2.2-3.8).
Associated Press
Wastewater injection can cause significant earthquakes
Wastewater from fracking is usually disposed of by injection into deep wells. This step is more likely to cause large earthquakes because it leads to relatively large, rapid, and deep pressure changes.
2011 Oklahoma earthquake
Decreasing injection rates can reduce the magnitude and frequency of earthquakes.
Youngstown, Ohio • Injection in proximity to fault lines led to
earthquakes, the greatest magnitude 3.0 • In response to increasing seismicity, injection rate
was reduced. • Seismicity decreased significantly within a month
of the change.
Questions?
Water Contamination and Induced Seismicity
1. Does fracking cause earthquakes?
2. How much water does fracking use?
3. Does fracking contaminate drinking water?
Fracking is not uniquely water-intensive
• More water-intensive than conventional natural gas and some renewables.
• Refracturing is more resource-intensive than initial fracturing. – Bakken Shale: twice as much water/30% gain in production.
• Less water-intensive than some other methods:
Fracking fluid often can’t be recycled because of its
composition
• Contains compounds other than water for purposes such as: – Corrosion inhibitors
– Thickening agents – Friction reducers
Water Contamination and Induced Seismicity
1. Does fracking cause earthquakes?
2. How much water does fracking use?
3. Does fracking contaminate drinking water?
To dispose of wastewater more safely, we need to know more about existing faults and how they’re affected by adding stress and pressure from the injection of large volumes of wastewater.
US Energy Information Administration (2011)
Fracked wells have been linked to water contamination...
• Eight wells in Pennsylvania and Texas were recently linked by their “chemical fingerprints” to groundwater contamination.
• A paper published this August by Darrah et al. took a closer look at contaminated wells in Pennsylvania’s Marcellus Shale formation.
Darrah et al. 2014
...Which likely results from lapses in well integrity such as leaky
pipes and seals
Concentrations of helium, neon and argon in the methane-contaminated water weren’t consistent with fracking, but were consistent with poor well integrity.
Faulty casing Abandoned-well leakage
Migration from depth
• Injecting wastewater near faults can lead to seismic activity. – Fracking itself is much less likely to do so
• Fracking uses less water than many other nonconventional fuel sources.
• Water contamination from fracked wells has been linked to problems with the well construction and not to the fracking process.
Water Contamination and Induced Seismicity
Questions?
Roadmap for the evening
1. Hydraulic Fracturing: How…and Why?
2. Water Contamination and Induced Seismicity
3. Impact of Fracking on Climate Structure
Impact of Fracking on Climate Structure
What is a Greenhouse Gas?
• Gases in atmosphere retain some heat that Earth is radiating
• More heat absorbing
gas = more heat retained
Transition to Renewable Energy
Coal Natural Gas Renewables
VS
How does it compare to coal?
1 kg CO2 for every kWh produced
emits half that amount!
And that’s the end of that!
…or is it?
New Findings in 2011!
Leaking of Methane: the Other Greenhouse Gas
Methane Amount of methane released is much lower than CO2… So why does it matter?
2007 IPCC Assessment Report 4
Not All Greenhouse Gases are Made Equal
• Global Warming Potential- amount of heat trapped by gas compared to CO2 over a period of time
• Greenhouse gases often expressed as g CO2 equivalents
Greenhouse Gas
GWP (20 yrs) GWP (100 yrs)
GWP (500 yrs)
CO2 1 1 1
CH4 70 25 10
Questions?
Where is the natural gas escaping?
Methane But how much natural gas is lost?
• Leaky wellhead components
• Routine venting
• Transportation • Storage
• Water flowing back to surface
The First Study (2011)
Methane 3.6-7.9% emitted directly to atmosphere!
Howarth et. al. 2011
Let’s Compare it to Coal! G
ram
s of
CO
2 eq
uiva
lent
s pe
r kW
h pr
oduc
ed
55
110
160
270
215
0
*low estimate obtained assuming most advanced technology is used
Modified from Howarth et. al. 2011
Low Estimate High Estimate Low Estimate High Estimate Surface-mined Deep-mined
Shale Gas Conventional Gas Coal
CO2
Methane
High Level of Uncertainty • Relies on very limited amount of data
• Some of this data was collected as early as 1996 • Uses conservative estimates to offset this
Despite using conservative estimates…
• New study released by Allen et. al. in 2013 obtains value of only 0.42% natural gas release
High Variation Among Studies
Allen’s data collection sites were selected by industry Modified from Howarth et. al. 2014
0% 2% 4% 6% 8% 10%
Howarth 2011, conventional gas
Howarth 2011, shale gas
Allen 2013, US average
Petron 2012, tight-sands gas
Karion 2012, shale gas
Brandt 2013, US average
Miller 2013, US average
Leak Rate
Some Emissions Can be Reduced! Capture and storage Flaring
these only reduce emissions from venting
Reasons for High Uncertainty and Variation
• Data from a few sites applied to many sites
• Advancing technology
• Many observation sites are selected by industry
• Data collection occurs infrequently
• Global warming potentials might be calculated differently from study to study
Impact of Fracking on Climate Structure
Is natural gas better for the climate than coal?
Perhaps! Perhaps not…
• natural gas emits half as much CO2 as coal
• extraction processes release methane, a more potent greenhouse gas
• many emissions are accidental • some emissions can be
reduced by capture or flaring
Due to high uncertainty, climate improvement should probably not be a reason to rely on natural gas
Questions?
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