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“Let’s Talk Energy”
WINTERSESSION 2017
Program of Topics
Introduction: Why Energy?
Oil/Gas
Alternative Energy
Solar
Wind
Nuclear
Biofuels
Why should we care about energy?
Why should we care about energy?
● Energy powers our world
● Energy consumption correlates with GDP, quality of life
Why should we care about energy?
● Developing countries need better access to energy to enhance growth
○ Two of three Africans have no access to power
● Population growth will increase energy needs
○ Must supply energy sustainably
■ Avoid over-extraction of resources
■ Limit damage from climate change...
A primer on climate change
A primer on climate change
A primer on climate change
A primer on climate change
Energy usage can enhance climate change
● The energy sector is the largest contributor to worldwide CO2 emissions
○ A shift from fossil fuels to cleaner renewables could reduce this
○ Complications:
■ Technological concerns (i.e. intermittency, storage)
■ Longevity of existing fossil fuel plants, economic concerns
■ Political desires
Oil and Gas
❧
What is it?
❧
❧ Crude Oil
❧ Brent vs. WTI
❧ WTI – Light
❧ Brent – Less Light
❧ API Gravity
❧ Sweet vs. Sour
❧ Natural Gas (Shale Gas)
❧ Seismic surveys to locate
❧ About 45% of American natural gas
production and 17% of American oil
production depend on fracking
❧ Combined vs. Open Plants
Where is it found?
❧ Previously, heavily pressurized and
heated packs of dead
phytoplankton ~ hundreds of
millions of years old.
❧
❧ Photo of us reserves of oil and methane
How does drilling occur?
❧
❧
Economics of O/G
❧
❧ A classic economic commodity,
supply-and-demand
❧ Current oil price: flooding of
US markets by OPEC driving
prices down
❧ Solution?
❧ 1.6 trillion barrels proven, 35
billion consumed/year, at least
50 years of oil without anymore
exploration
The future of O/G
❧
❧ Makes 60% of our current
energy consumption, can we
drop altogether?
❧ Benefits: easy energy
storage; high energy density
❧ Natural gas: water
contamination, methane
leakage?
Solar Energy
Technology: Photovoltaic Cells
▶
▶
Energy conversion efficiency:
▶
Commercial cells ~20%.
▶
Research labs demonstrated
~40-50%.
Different materials and
designs.
▶
Cost vs. efficiency?
Technology: Solar Thermal Collectors
▶
Energy conversion efficiency:
▶
(Sunlight to heat) x (heat to electricity): ~ 20%
Trends
▶
0.4% of U.S. energy consumption.
▶
Over 1% of global energy consumption
Future of Solar Energy
Wind Energy
Key terms
Scale
Utility: Large, > 20 MW of electricity
Land or offshore
Distributed (smaller)
Residential, commercial
Horizontal Axis Turbines
Vertical Axis Turbines
History
Originated from windmills used in agriculture
Research accelerated due to...
1970s oil crises
1990s tax credits
Currently ~75 GW of wind energy in the US
~450 GW globally
Picture: 1980s wind farms installed in California
Current Events and Economic Trends
China’s wind construction
Gansu Wind Farm -> Expected to produce 20 GW of power
Europe: becoming established (42% of energy in Denmark from wind)
US: cheaper than coal; comparable to natural gas
Price reduced through recent tax credits
Prices down;
Installations up
Future of Wind Energy
US: More offshore projects?
Large capacity in China and the US
Bladeless turbines and kite systems in development
Improvement of current systems - new materials, dimensions
Projected wind installations by 2030
First US offshore wind: off Block Island (RI)
Roadblocks
Aesthetic displeasure
Threat to birds (?)
Noise
Intermittency/Variability
Reliance on governmental tax cuts
Changes with current political climate?
Biofuels
First and second generation biofuels; biomass
What is a
Biofuel?
-fuel produced through
biological processes
-typically used as
transportation fuels
⚫First Generation – from sugars, grains, or seeds
⚫Alcohols (ethanol, butanol)
⚫Biodiesel (esters)
⚫Plant oil
⚫Second Generation – from lignocellulose
⚫Alcohols (ethanol, butanol) through enzymatic hydrolysis
⚫Thermochemical fuels (methanol, Fischer-Tropsch liquids)
⚫Algae lipids
Pros
Cons
⚫Mostly renewable
⚫Land and resource intensive
⚫“Cleaner”
⚫Food security issues
⚫Potentially carbon-neutral
⚫Infrastructure adaptability
Why Biofuels?
Source: Energy Technology Perspectives. International Energy Agency, 2014
Production
and
Challenges
Source: Lawrence Livermore National Laboratory
Energy Resource
-Goal: commercially produce
energy-intensive biofuels
that can be readily
integrated into current
infrastructure and have
minimal social and
environmental impacts
Estimated Land-Use
Requirement in 2030
(km2/TWh per year)
Ethanol from Corn 347.1
Source: http://www.biofuel.org.uk
Wind
72.1
Solar PV
36.9
Natural Gas
18.6
Coal
9.7
Nuclear
2.4
Source: Energy, Water, and Land. National Climate Assessment 2014
Howitworks
• Currentlyprovide20%ofpower- butmanyareshuttingdown
• Allactivenuclearpowerplantsusenuclearfissiontogeneratetheirenergy
• Fissionistheprocessofsplittinglargeatomsinsmallercomponents
• Thereactionreleasesnucleithatgoontofurthersplitmorelargeatoms
(inducingachainreaction)
• Inareactor,carefuldesignandcoolingmechanismsareusedtocontrolthe
chainreaction
• Thissplittingalsoreleasesimmenseamountsofenergyintheformofheat
• Thisheatisusedtoproducesteamthatfeedsintoturbinethatproduces
electricitywiththehelpofagenerator
TypesofReactorscurrentlyinuse:
• BoilingWaterReactor(mostoutdated)
Keypoints:
• Waterwhichpassesoverthereactor
coreisusedformoderatingthe
reaction,coolingtherodsand
producingsteam
• Dangeroffuelleakmightmakethe
waterradioactiveandspreadtorest
ofreactor
• Typicaloperatingpressureof70 atm
(wherewaterboilsatabout285C)
• GivesaCarnotefficiencyof42%with
apracticaloperatingefficiencyof
around32%
TypesofReactorscurrentlyinuse:
• PressurizedWaterReactor(mostcommon)
Keypoints:
• Herethewaterwhichpassesoverthe
reactorcoretomoderate andcool
doesnotflowtotheturbine.
• Theprimaryloopwaterproduces
steaminthesecondaryloopwhich
drivestheturbine.(sonodangerof
radioactivedamagetoturbinegiven
fuelleak)
• PWRcanoperateathigherpressure
andtemperature,about160 atmand
315C.
• ProvidesahigherCarnotefficiency
• Reactorismorecomplicatedand
morecostlytoconstruct.
TypesofReactorscurrentlyinuse:
• Fast-BreederReactor
Keypoints:
• Coolingandheattransferisdonebya
liquidmetal(usuallysodiumor
lithium)
• Requiresahigherenrichment ofU235thanalight-waterreactor(15to
30%)
• Nomoderatorisusedinthebreeder
reactorsincefastneutronsaremore
efficientin transmuting U-238toPu239
Dangers
• Concernswithwastestorage(wherewillwebein10,000years)
• Previousaccidents(Fukushima,Chernobyl,ThreeMileIsland)
• Relatedtonuclearweapons,proliferation
LookingForward
• Economics:Manyplantsareshuttingdown,solarand
windarebecomingcheapermuchfaster,newplant
designstakeyearstocommercialize
• PebbleBedGascooledreactors(allowsforrefueling
withoutshuttingdownthereactorandsmallerscale
designs)
• saferreactors?
• NuclearFusion
•
•
•
•
Heatatomsuntiltheyfuse(+100MC)
Difficulttocontaintheplasma
Hugepotentialfornetenergypositive
Highcosts
Energy Storage
Importance
Energy Production
Oil/Gas,
Solar,
Coal,
Wind,
Nuclear,
Biofuels,
Hydroelectricity,
etc.
Doesn’t mean much if you can’t store the energy
Demand fluctuates
“Energy storage captures excess electricity at high efficiencies for optimal use during outages, peak
hours, or whenever effective grid management is a challenge.”
Endgame – Sustainability,
Consider – Storage, Economics
Accumulators (Energy Storage Devices)
Categories: Electrical, Mechanical, Thermal, Chemical
• Batteries (Lead Acid, Nickel Cadmium, Lithium Ion, …)
• Flywheels
• Compressed Air
• Thermal
• Pumped Hydropower
• Etc.
Grid-Scale (Centralized) Storage
• Pumped hydropower – “The largest-capacity form of grid-scale energy storage available
today”
Efficiency
Account for 99% Worldwide
70% - 75%
Distributed Energy Storage
Microgrid
Energy Policy
The US in an International Context
Paris Climate Agreement (COP21)
▶
▶
▶
▶
First universal, legally binding, global climate deal
195 countries
Global action plan - avoid dangerous climate
change, limit global warming to 2 degrees Celcius
(compared to pre-industrial levels)
The Obama initiatives for CO2 reduction, cap and
trade program, and sustainable energy
development
Cap & Trade Vs. Carbon Tax
▶
Basic idea: provide economic incentives for reducing pollutant emissions, don’t
need to know where to cut beforehand, encourage new R&D, generate
government revenue
▶
Cap and Trade: Government allocates a specific number of permits to emit
specific quantities of a given pollutant over a time span; can auction and trade
▶ Guarantees falling below emissions
▶ Proposed by Obama administration but not passed
▶ Carbon tax - price on greenhouse gas emissions, charged $ amount
▶ Stable carbon prices, can go cheaper than target (but probably won’t in
near future)
▶
In the US, we have a national market targeting acid rain, regional markets in
nitrous oxide, and state markets in carbon dioxide (CA only)
Trump & Energy
▶ “Unleash America's $50 trillion in untapped shale, oil, and natural gas reserves, plus
hundreds of years in clean coal reserves.”
▶
No more Clean Power Plan
▶
Open more federal lands to energy production… more pipelines? Lower prices?
▶
Bring back coal? Trump will remove regulation, but can’t make coal competitive
▶
Supports nuclear power and hydropower
▶
Solar and wind industry will lose subsidies… but they don’t need government
subsidies to be competitive?