Non-renewable energy
Chapter 15
This lecture will help you understand:
Our energy sources
Coal, natural gas, oil use
Depletion of oil supplies
Alternative fossil fuels
Environmental impacts of fossil fuels
Political, social, and economic impacts offuel use
Energy conservation and efficiency
Nuclear power
Central Case Study: Offshore Drilling and the Deepwater Horizon Blowout
On April 20, 2010, the Deepwater Horizon drilling rig exploded in the Gulf of Mexico
Killed 11 people
Spilled 230 million gallons (2,000 gallons/minute) of crude oil into the Gulf
It took 86 days to seal the well
The oil spill was the largest accidental spill in history
Due to careless corporate shortcuts and weak governmental oversight
We are addicted to oil
The Deepwater Horizon’soil spill resulted from our insatiable appetite for petroleum
Particularly for cars
The oil industry has drilled farther and farther out to sea
Increasing risks for major accidents
We must reduce our dependence on oil
We use a variety of energy sources
We use energy in our homes, machinery, and vehicles and in products that provide comfort and conveniences
Most of Earth’s energy comes from the sun
Solar, wind, hydroelectric, photosynthesis, biomass
Fossil fuels are highly combustible substances from the remains of organisms from past geologic ages
Oil, coal, natural gas
Fossil fuels provide most of our energy for:
Transportation, heating, cooking
Electricity is easy to transfer and has lots of uses
Fossil fuels: our dominant source of energy
Global consumption of fossil fuels is at its highest level ever
Resources are renewable or nonrenewable
Renewable energy: supplies are not depleted by our use
Sunlight, geothermal energy, and tidal energy
Nonrenewable energy: once depleted, it cannot be renewed (oil, coal, natural gas)
We will use up Earth’s accessible store in decades to centuries
To replenish the fossil fuels we have depleted so far would take millions of years
Nuclear power: is nonrenewable because uranium ore’s supply is limited
It takes energy to make energy
We don’t get energy for free
To harness, extract, process, and deliver energy requires substantial inputs of energy
Drilling for offshore oil requires millions of dollars for infrastructure to extract and transport the oil
All this requires huge amounts of energy
Net energy is the difference between costs in energy invested and benefits in energy received
Net energy: Energy returned – Energy invested
Energy returned on investment (EROI)
Energy returned on investment (EROI):
EROI: energy returned/energy invested
Higher ratios mean we receive more energy than we invest
Fossil fuels have high EROI
EROI ratios can change
They decline when we extract the easiest deposits first
We now must work harder to extract the remaining reserves
U.S. oil EROI ratios have gone from 100:1 to 5:1
Reserves and use are unevenly distributed
Some nations have large reserves, others don’t
The Middle East has 67% of the world’s crude oil
Russia holds the most natural gas
The U.S. possesses more coal than any other country
People in developed regions consume the most energy
The U.S. has 4.5% of the world’s population but uses 20% of its energy
Developing nations use energy for subsistence activities
Agriculture, food preparation, and home heating
Developed nations use fossil-fuel-driven machines
Fossil fuels are created from fossils
Fossil fuels were formed from organisms that lived 100–500 million years ago
Anaerobic decomposition occurs with little or no air
Deep lakes, swamps
Produces fossil fuels
Three major types of fossil fuels
Coal is organic matter (plants) placed under high pressure
Natural gas is mainly methane (CH4)
Oil (crude oil) is liquid made of hydrocarbons
Petroleum is natural gas plus oil
Formed from organic material (plankton) in coastal marine waters
Biogenic gas is created in shallow water by anaerobic decomposition of organic matter by bacteria
Swamp gas, landfill gas
Thermogenic gas is formed deep underground
Coal
The world’s most abundant fossil fuel
Created 300–400 million years ago
Extracted using three methods
Strip mining - for deposits near the surface
Subsurface mining - for deposits deep underground
Mountaintop removal
Coal helped drive the industrial revolution
Coal is used to generate electricity
Converting water to steam, which turns a turbine
Coal use has a long history
The U.S. and China are the primary producers and consumers of coal
Coal varies in its qualities
Coal varies in water and carbon content and its impurities
It has sulfur, mercury, arsenic, and other trace metals
Coal in the eastern U.S. is high in sulfur because it was formed in marine sediments
Burning coal releases impurities
The Earth holds enough coal to last a few hundred years
Natural gas burns more cleanly than coal
The fastest growing fossil fuel in use today
25% of global commercial energy consumption
It is versatile and clean-burning
Emits ½ as much CO2 as coal, ⅔ as much as oil
It is used to generate electricity, heat homes, and cook
Liquefied natural gas (LNG) I sgas converted to liquid
Can be shipped in refrigerated tankers
Russia leads the world in production
The U.S. leads the world in use
World supplies are projected to last about 60 more years
We drill to extract oil
Oil accounts for 1/3 of the world’s energy use
Oil is under pressure and often rises to the surface
Drilling reduces pressure, so oil is harder to extract
Primary extraction is the initial extraction of available oil
Secondary extraction is when solvents, water, or steam is used to remove additional oil
“Fracturing” breaks rocks to release gas
We lack the technology to remove every bit of oil
Not all oil can be extracted
Technology limits how much can be extracted
Economics limits how much will be extracted
It gets harder and more costly as oil or gas are removed
The amount of “economically recoverable” oil and gas is based on the price of the fuel
At higher prices, economically recoverable amounts approach technically recoverable amounts
Proven recoverable reserve is the amount of a fossil fuel that is technically and economically feasible to remove under current conditions
Secondary oil extraction is costly
Offshore drilling produces oil and gas
We drill for oil and gas on land and under the sea
Drilling rigs are fixed or floating
The Gulf of Mexico has 35% of U.S. oil (10% gas)
It has 90 drilling rigs and 3,500 platforms
Companies must drill deeper and deeper for oil
Up to 10,000 feet deep
Deep water drilling is risky
It took 86 days to plug the leaking Deepwater Horizon’s well
In 2008 Congress lifted a moratorium on off shore drilling
Obama opened up most of the U.S. coast to drilling
The public’s reaction to the Deepwater Horizon’s spill forced Obama to backtrack
Cancelled drilling permits until new safety measures were devised
Oil refineries create petroleum products
Once extracted, oil is refined
Hydrocarbons are sorted for different uses
Oil is used for fuel,
plastics, tar, asphalt, fabrics, etc.
Petroleum products have many uses
We may have depleted half our reserves
We have used half (1.1 trillion barrels) of our oil reserves
Reserves-to-production ratio (R/P ratio):
The total remaining reserves divided by the annual rate of production (extraction and processing)
At current levels of production (30 billion barrels/year), we have about 40 years of oil left
We will face a crisis not when we run out of oil, but when
We hit peak oil: production peaks then declines
Production declines once reserves are 50% depleted
We are facing an oil shortage
Geologist M. King Hubbard predicted that U.S. oil production would peak around 1970
His prediction was accurate, and U.S. production continues to fall
Hubbard’s peak is the peak in U.S. production (1970)
Global oil production is peaking
Predicting an exact date for peak oil is hard
We won’t recognize that we have passed peak production until several years have passed
Companies and governments do not disclose their true amount of oil supplies
Most estimates say oil will peak between 2010 and 2040
Peak production will occur
It will have momentous economic, social, and political consequences
Our lives will be profoundly affected
The long emergency
“The long emergency”: lacking cheap oil to transport goods, our economies collapse and become localized
Large cities will have to have urban agriculture
Fewer petroleum-based fertilizers and pesticides would mean increase in hunger
Suburbs will become the new slums, a crime-ridden landscape littered with the hulls of rusted-out SUVs
More optimistic observers argue that as supplies dwindle, conservation and alternative energies will kick in
We will be saved from major disruptions
Canada is mining oil sands
Oil sands (tar sands) are sand deposits with bitumen
A form of petroleum rich in carbon, poor in hydrogen
Degraded and chemically altered crude oil deposits
Removed by strip mining
Requires special
extraction and
refining processes
Most is in Venezuela
and Alberta, Canada
Oil shale is abundant in the U.S. west
Oil shale is sedimentary rock filled with kerogen (organic matter)
Can be processed to produce liquid petroleum or burned like coal
Extracted by strip mines or subsurface mines
World’s supplies may equal 600 billion barrels
40% is in the U.S., mostly on federally owned land in Colorado, Wyoming, and Utah
Methane hydrate shows potential
Methane hydrate (methane ice) are molecules of methane in a crystal lattice of water molecules
Occurs in arctic locations and continental shelves
Immense amounts could be present
Twice as much as oil, gas, coal combined
We do not know how to extract it safely
Extraction could release large amounts of methane—a greenhouse gas—and cause landslides and tsunamis
Alternative fossil fuels have drawbacks
Their net energy values are low because they are expensive to extract and process
EROI ratios are about 2:1 compared to oil’s 5:1
Extraction devastates the landscape and pollutes water
Immense amounts of water are needed – reserves are in arid areas
Polluted wastewater is held in huge reservoirs
Combustion emits as much greenhouse gases and pollution as oil, coal, and gas
Fuel emissions pollute air
Carbon dioxide is released from land into the air
Driving changes in global climate
Emissions cause severe health problems
Cancer, irritation, smog, poison
Technology and legislation
can reduce pollution
Clean coal technologies
Clean coal technologies are technologies, equipment, and approaches to remove chemical contaminants
While generating electricity from coal
Scrubbers chemically convert or remove pollutants
Coal that contains lots of water can be dried
Gasification is when coal is converted into cleaner synthesis gas (syngas)
Which can be used to turn a gas or steam turbine
These technologies have reduced pollution
But “clean coal” is still a dirty way to generate power
Can we capture and store carbon?
Carbon capture and carbon storage (sequestration)
CCS captures CO2 emissions, converts it to a liquid, and stores it underground or in the ocean
Is planned for the U.S. $1.5 billion FutureGen project
This technology is still too unproven to depend on
The gas may escape and contaminate water or acidify the oceans
It is energy intensive and reduces coal’s EROI
It prolongs our dependence on fossil fuels
Carbon capture and sequestration
Fossil fuels pollute water and air
The Deepwater Horizon’sspill showed that offshore drilling is very dangerous
The Gulf of Mexico suffered many impacts
Countless animals (birds, shrimp, fish, etc.) died
Coastal marsh plants died, leading to erosion
Fisheries were devastated, and fishermen lost jobs
Tourism suffered
Economic and social impacts will last for years
Drilling for oil in the Arctic
Melting ice in the Arctic is opening up new shipping lanes
Nations want to get to oil and gas deposits
Any oil spill will pose severe pollution risks
Icebergs, pack ice, storms, cold, and winter darkness will hamper response efforts
Frigid water temperatures will slow the natural breakdown of the oil
Coal mining devastates natural systems
Most water pollution comes from non-point sources
Cars, homes, gas stations, businesses, storage tanks, the atmosphere, etc.
Mining pollutes water, destroys habitat
Coalbed methane sites pump methane into coal seams, contaminating soil and killing vegetation
“Hydrofracking” is water, sand and chemicals are injected into natural gas wells
Toxic wastewater is sent to sewage treatment plants that release treated water into drinking sources
The public pays the environmental costs
Drilling requires land, roads, infrastructure (e.g., houses)
Pollutes soil and water, fragments habitats
Toxic sludge is stored in ponds
Policymakers are debating opening up ANWR
Directional drilling is when wells are drilled away from a drilling pad, requiring fewer pads
Costs are not internalized in the market price of fuels
Taxpayers paid medical costs, cleanup, etc.
Gas prices and utility bills don’t cover costs of the fuel
Government subsidies keep fossil fuel prices cheap
Residents may or may not benefit
Oil companies provide jobs for millions
107,000 work in the Gulf of Mexico alone
But more work in tourism, service jobs, and fishing jobs
Citizens in developing nations don’t benefit from drilling
Corporations pay off the governments
Few environmental or health regulations exist
Many still live in poverty, without water or electricity
An Ecuadoran court fined Chevron $9.5 billion for environmental and health impacts
A U.S. court issued an injunction to stop payment
Many nations depend on foreign energy
Nations importing fossil fuels are vulnerable to supplies becoming unavailable or costly
Seller nations control prices, causing panic
The U.S. imports 67% of its crude oil
Oil supply and prices affect economies
Hurricanes Katrina and Rita (2005) destroyed offshore platforms, causing oil and gas prices to spike
The politically volatile Middle East has the majority of oil reserves
The U.S. supports nondemocratic leaders
e.g., in Tunisia and Egypt
Following the 1973 oil embargo, the U.S. enacted policies to reduce its dependence on foreign oil
The U.S. has policies to reduce foreign oil
Secondary extraction at old oil wells
A 1-month emergency stockpile of oil
It capped the price domestic producers can charge
Funding research into renewable energy sources
Enacting conservation measures
Drilling in ever deeper waters
Many want drilling in ANWR
But drilling won’t help much and will destroy the nation’s last wilderness
U.S. imports more oil from non-Middle-Eastern countries
The global trade in oil
Oil embargoes and natural disasters (e.g., Hurricanes Katrina and Rita) create panic and increase oil prices
How will we convert to renewable energy?
Fossil fuel supplies are limited
Their use has health, environmental, political, and socioeconomic consequences
Many people and nations are moving toward clean, renewable energy sources
France, Germany, and China are far ahead of the U.S.
We need to prolong fossil fuels through conservation
Lifestyle changes, reducing energy use, technology to improve efficiency
Fossil fuel use has consequences
Energy efficiency and conservation
We need to minimize our use of dwindling fossil fuels
Energy efficiency is obtaining a given amount of output while using less energy input
Results from technological improvements
Energy conservation is the practice of reducing energy use
Efficiency is one way toward conservation
We can extend our nonrenewable energy supplies
Be less wasteful
Reduce our environmental impact
Personal choice and efficient technologies
We can choose to reduce energy consumption
Drive less, turn off lights, buy efficient machines
We don’t have to decrease our quality of life
Reducing energy use will also save money
Energy-consuming devices can be made more efficient
Cars and power plants lose ⅔ of energy as waste heat
The U.S. has become more efficient, but we can do better
Cogeneration is when excess heat produced during electrical generation can heat buildings or produce other power
It can double the efficiency of a power plant
Efficiency in homes, products and cars
Improvements can reduce energy to heat and cool buildings – passive solar, insulation, plants, roof color
Appliances have been reengineered to increase efficiency
Savings on utilities exceeds the appliances’ costs
Vehicles are the best way to easily save fossil fuels
Electric cars, hybrids,
hydrogen fuel cells,
better engines
Automobile efficiency affects conservation
The OPEC oil embargo of 1973 caused increased fuel conservation, but it didn’t last
Without high prices and shortages, there was no incentive to conserve
Government research into alternative energy decreased
Speed limits increased
Policy makers did not raise the corporate average fuel efficiency (CAFE) standards
Low U.S. gas prices do not account for external costs
Low fuel taxes reduce incentives to conserve
CAFE standards
CAFE standards mandate higher fuel efficiency in cars
Fuel efficiencies fell from 22 mpg (1984) to 19 (2004)
They climbed to 21.1 in 2009
In 2009 Congress mandated that cars must get 35 mpg by 2020
European and Japanese cars are twice as efficient as U.S. cars
The Cash for Clunkers program
In 2009, the Obama administration tried to improve fuel efficiency, stimulate economic activity, and save jobs
The “Cash for Clunkers” program paid Americans $3,500 to $4,500 to turn in old cars and buy new, efficient ones