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Chpt. 7: Non-renewable Energy Sources
Energy may be our most important resource, and energy availability may ultimately limit economic and
population growth. Abundant energy makes it easy to be sustainable because it can be used to produce
essential resources such as food and potable water where they are scarce. For example, countries like the
United Arab Emirates are turning desert into oasis using desalinization plants because they have little fresh
water but abundant seawater and energy stored in oil. However, many areas of the world are experiencing
energy shortages. Furthermore, most of our energy comes from burning fossil fuels, which adds the
greenhouse gas CO2 to the atmosphere, intensifying global warming. To become sustainable, our society must
transition from non-renewable fossil fuels to renewable energy sources. Having covered oil in Chpt. 5, we will
review environmental problems associated with use of the remaining non-renewable energy sources.
Introduction
Energy comes in many forms, including chemical, mechanical, electrical, heat, and light. We use energy
to perform work, i.e., to move matter, usually by converting it from one form that stores it to another. For
example, fossil fuels and electrochemical batteries store chemical energy. To propel conventional autos that
have internal combustion engines we burn gasoline or diesel to convert the stored chemical energy to
mechanical energy. Electric cars convert chemical energy stored in electrochemical batteries to mechanical
energy, with the added advantage that they don’t emit CO2.
Some forms of energy are more useful than others. Heat is considered low quality energy because it is
dispersed. It is commonly a by-product of mechanical work; the more heat produced by friction and lost, the
less efficient is the mechanical device. Electricity is a high quality form of energy because we can transport it
through conductive wires, store it in batteries, and use it to make other forms of energy. We also can use it for
electronic communication, which makes it indispensable to modern society. As a result, we typically convert
other forms of energy to electricity. For example, mechanical energy in flowing water or steam is converted to
electrical energy using a turbine. According to the second law of thermodynamics, each time we convert other
forms of energy to electricity we lose some energy, but the increased utility of electricity balances this loss.
Energy availability is what most likely limited human population in the past. Humans first obtained
energy from biomass (wood and dung), then coal, and finally energy-dense oil (National Science Board 2009).
Global energy consumption increased dramatically during the 20th century i. Abundant energy has allowed
humans to multiply and increase their standard of living to levels never previously reached (Kellogg and
Pettigrew 2008). Energy from oil fueled the green revolution of the 20th century that quadrupled agricultural
productivity worldwide, allowing the global population to increase at an exponential rate. We currently use oil
and the energy it provides to make fertilizers and pesticides, to run the machines that plant and harvest crops
and till the soil, and to transport the harvest to market. We use energy to pump groundwater to the surface for
irrigation in arid regions, transforming deserts to productive cropland. With unlimited energy, we can turn the
most inhospitable environment into heaven on Earth. However, as we’ll see below, we do not have unlimited
energy, and even worse, our use of fossil fuels may make Earth inhospitable. Like Faust, we make a devil’s
bargain when we choose to use fossil fuels for energy.
Experts expect the global consumption of energy to double between now and 2050 due to increases in
global population and of wealth resulting from the globalization of markets ((Friedman 2008), pp. 38-9). In
their Annual Energy Outlook report published in 2010 the US Energy Information Administration (EIA)
predicts that overall energy demand will increase 36% between 2009 and 2035 (Figure 1). They add that
renewable energy “will have to play a central role in moving the world onto a more secure, reliable and
sustainable energy path (EIA 2010).”
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Figure 1. Primary energy use by fuel, 1980-2035. From IEA Annual Energy Outlook (2010).
Developed countries consume a disproportionately high amount of energy. For example, the US makes
up 5% of world population, but accounts for 25% of the energy consumption. Fossil fuels account for roughly
80% of US energy consumption (Figure 1), but they are non-renewable resources. The energy-dense liquid oil
is the most valuable fossil fuel. It is the primary source of energy in the US (Table 7-1), and provides ~95% of
the energy used in transportation ((EIA 2010), Table A2). However, as discussed in Chpt. 6, oil is in
increasingly short supply. This has major implications for the world economy and the energy security of
nations like the US.
Table 7-1: US Energy Use by Source in 2008 (EIA 2010)
Energy source
% US Energy
% of electricity
Petroleum
38
1
Coal
22
51
Natural gas
24
17
Nuclear
8
21
Renewable energy 6
Biofuels
1
9% total
renewables
*is this primary or secondary energy? Check.
A common feature of all societal collapses is that human population density became too great for the
environment to support (MacKay 2009). Because renewable energy sources are diffuse (have small energy
densities), they alone cannot meet demand in areas of the First World with high population density and energy
consumption. Meeting the energy needs of these areas as fossil fuels become scarce will be a challenging
technological problem, and may require the import of electricity produced in low-density areas using
renewable energy sources. Because useful energy is limited, energy supply may set physical limits to economic
and population growth in the near future.
To discuss energy and power supply and demand we must first introduce their scientific definitions and
units of measure. Energy is a measure of how much work can be performed. In this book we will try to
consistently use the kilowatt-hour (kWh) as a measure of stored or used energy. Power is the rate at which we
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use energy in kilowatt-hours per day (kWh/d). The total amount of energy used to do work depends on the
rate at which you use the energy (power) and how much time you work: energy (kWh) = power (kWh/d) x time
(d). As noted by MacKay (2009), "One kilowatt-hour per day is roughly the power you could get from one
human servant. The number of kilowatt-hours per day you use is thus the effective number of servants you
have working for you." As of 2009 Americans consume an average of 250 kWh per person day, meaning that
they have 250 “energy slaves” doing work for them every day. Europeans consume half of that, but that does
not include the embodied and transport energy of imported goods, which raises it to about 165 kWh/day
(MacKay 2009).
Efficiency is the ratio of the work output to the energy input; sometimes power is used in place of
energy because power is the rate of energy use. We calculate it as a fraction, with values ranging from zero
(completely inefficient) to one, or as a percentage from zero to 100%. For example, fuel efficiency measures the
distance traveled (miles) per amount of fossil fuel energy (per gallon of gasoline). Lighting efficiency expresses
the amount of light (lumens) per quantity of power (watts). Electrical efficiency is electrical power used per
amount consumed. Efficient systems use most input energy to do useful work; inefficient systems use much of
the input energy to produce wasted heat or noise.
Energy supply is classified as either primary energy or secondary energy. Primary energy is energy
captured from nature that is used directly. Secondary energy is produced by converting primary energy to a
more useful form such as electricity or hydrogen. Some energy is lost during the conversion of primary to
secondary energy, usually about one-third.
Table 7-2: Percentage of Total Primary Energy Supply (TPES) and World CO2 Emissions by Fuel in 2005*
Energy source
Oil
Coal
Natural gas
Nuclear power
Hydroelectric
Combustibles
Other
Percentage of TPES
34
26
21
6
2
10
1
*From (Richter 2010)
Percentage of world CO2 emissions
40
40
20
0
0
0
0
Besides ensuring a sustainable energy supply, we also must strive to mitigate GCC by reducing
greenhouse gas emissions. Energy use is responsible for 70% of greenhouse gas emissions. More specifically,
70% of the excess CO2 in the atmosphere comes from burning of fossil fuels, the other 30% coming from
deforestation. Energy use is divided into four categories, each of which have different problems and will require
different solutions to decrease greenhouse gas emissions. In the US primary energy use and greenhouse gas
emissions (CO2e) for these categories are transportation 29% and 27%, industrial 32% and 12.4%, residential
21% and ?%, and commercial 18% and ?%. Natural removal of excess greenhouse gas from the atmosphere will
take centuries. Thus, reducing greenhouse gas emissions by reducing energy use, substituting alternative
energy sources, or capturing and storing greenhouse gas released by fossil fuel burning is essential for the wellbeing of future generations (Richter 2010). No single technology can sustainably and affordably meet global
energy demand without greenhouse gas emission. The most effective approach will be to substitute a mixture of
known energy technologies for fossil fuel burning. As stated in “Building a Sustainable Energy Future: US
Actions for an Effective Energy Economy Transformation,” “Sustainable energy includes a wide range of clean,
equitable, reliable, renewable, secure, and economically viable energy strategies and solutions that value
environmental and ecosystem stewardship (National Science Board 2009)." In this chapter we will explore the
problems posed by use of the non-renewable energy sources coal, natural gas, and nuclear power. To measure
the total environmental impact of these energy sources, we need to measure the impact at every stage of their
life cycle, from cradle to grave, a process called Life Cycle Assessment.
Life Cycle Assessment
To assess whether a product is green people often look only at the operating costs. For example, an
energy-star rated refrigerator is considered green because it uses less electricity and therefore will cost less to
operate. That doesn’t necessarily mean it is the greenest choice. What if extraction of raw materials for that
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refrigerator damaged an ecosystem, resulting in loss of environmental capital? What if children manufactured
it in a sweat shop that was an unsafe and unhealthy working environment, causing loss of social capital? What
if it leaked poisons after disposal, causing further loss of environmental capital? To estimate the true cost of
any product we have to look at its effect on economic, social, and environmental capital at every stage of its life.
Life Cycle Assessment (LCA) is a form of Full Cost Accounting (FCA) that adds up the capital costs
incurred at each stage of a products life, including raw materials (R), production (P), use (U), and disposal (D).
In this section we will use LCA to estimate total energy costs = R + P + U + D of specific products and activities.
A subset of the total energy is the embodied energy, the energy used to manufacture the product = R + P.
LCA gives a complete picture of products’ environmental impacts. It shows which parts of the life cycle
most negatively affect the environment and should be targeted for reduction. For the consumer it’s useful for
comparing the impacts of two competing products. Sometimes the result of a LCA is a resource footprint or
emission footprint. For example, the carbon footprint is a measure of the mass of cumulated CO2 emissions
through the life-cycle of a product (Hertwich and Peters 2009).
LCA requires large amounts of data. For example, to estimate the total energy cost of a car, you would
need to know how much energy was consumed for use, maintenance, and disposal, for production of every car
part, and for production of the raw materials for every part. You would have to add up the energy costs
through the entire supply chain, a formidable task. Only recently have these types of calculators become
available. A good example is the Economic Input-Output Life Cycle Analysis (EIO-LCA) calculator at created
by the Carnegie Mellon Green Design Institute ii. It calculates embodied energy and greenhouse gas emissions
in CO2e for a wide range of products and activities. Table 7-3 shows that $1 million of cattle ranching
economic activity consumed 18.8 TJ energy. Energy was consumed to produce the grain fed to the cattle, to
transport the grain and the meat, to produce the fertilizers, pesticides, and antibiotics, and to operate the
Confined Animal Feeding Operations (CAFOs, more on this later). In addition, energy was used to mine and
distill the oil and to produce the electricity used at all stages of the life cycle. The EIO-LCA calculator also tells
us that $1 million of cattle ranching economic activity has a carbon footprint of 8550 MT CO2e (Table 7-3). Per
dollar of economic activity the amounts of energy consumed and CO2e produced are larger for cattle farming
than almost any other economic activity. If you are an investor concerned about the environment, you should
choose portfolios that don't invest in cattle farming.
Table 7-3: Embodied energy (TeraJoules) per million dollars of economic activity for each sector of the
cattle ranching industry
Sector
Total
Energy
TJ
Coal
TJ
NatGas Petrol
TJ
TJ
Bio/Waste
TJ
NonFossElec
TJ
Total for all sectors
18.8
3.39
3.36
9.58
0.213
2.23
Cattle ranching and farming
7.33
0
0.410
5.73
0
1.19
Power generation and supply
4.42
3.22
0.941
0.156
0
0.101
All other crop farming
1.18
0
0.078
0.890
0
0.209
Petroleum refineries
1.05
0.000 0.279
0.677
0.051
0.037
Grain farming
0.786
0
0.077
0.599
0
0.110
Truck transportation
0.609
0
0
0.603
0
0.006
Oil and gas extraction
0.519
0
0.424
0.044
0
0.051
Fertilizer Manufacturing
0.488
0.004
0.437
0.008
0.006
0.033
Pipeline transportation
0.165
0
0.126
0
0
0.040
Other basic organic chemical
manufacturing
0.149
0.025
0.070
0.015
0.028
0.011
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During the fuel use phase power plants emit 10 billion tons of CO2 per year, about one quarter of global
CO2 emissions. The US accounts for about 2.8 billion tons, 25% of that total iii. The 12 biggest CO2 emitting
power plants in the US are all coal-fired power plants iv. Carbon dioxide is also emitted during the raw material,
production, and disposal phases of fuel use. Table 7-4 shows LCA estimates of the amount of CO2 emitted per
unit of electricity produced for different primary sources of energy, called the emission intensity. Low
values mean lower greenhouse gas emissions. Table 7-4 also shows the amount of water consumed to produce
one kWh of electricity.
As mentioned previously, coal emits the most CO2 per unit energy (kWh), followed closely by oil.
Natural gas emits 62% as much CO2 per kWh as coal, a significant improvement, but still much higher than the
non-fossil fuels. To mitigate GCC we must phase out coal, oil, and natural gas as energy sources, and replace
them with solar, biomass, wind, geothermal, and hydroelectric. Although nuclear has a small carbon footprint,
it is a non-renewable and therefore non-sustainable source of energy, and it has many safety concerns that
make it less attractive than the renewable energy sources (discussed in detail below). Table 7-4 also shows that
the water intensity of biomass is two orders of magnitude higher than any other energy source, making it a
poor choice for arid regions that need to conserve water. Armed with this information, let’s look at other pros
and cons for each energy source.
Table 7-4: Carbon Dioxide and Water Intensities of Energy Sources*
Energy
CO2 intensity
source
(l/kWh)
Solar
26
Biomass
21
Wind
6.7
Geothermal 8.4
Hydro
11
Coal
530
Natural gas
330
Oil
500
Nuclear
17
Photovoltaic
Thermal
* Data from (Cho 2010).
H2O intensity
(l/kWh)
360
0
5.3
17
1.9
0.6
1.6
2.6
0
3.2
Coal
Never mind when fossil fuels are going to run out; never mind whether climate change is happening;
burning fossil fuels is not sustainable anyway (MacKay 2009).
Coal is a black or brown sedimentary rock formed from the remains of fossilized plants. Most coal
formed in swamps during the Carboniferous period (360-290 Million Years Before Present (MYBP)). Because
coal takes millions of years to form, it is considered a non-renewable resource, meaning that coal use is
unsustainable. Assuming a constant rate of consumption, current global reserves of coal would disappear in
about 300 years (MacKay 2009). However, coal consumption has been increasing at an exponential rate. In
the business as usual scenario, we will deplete coal in 60-90 years (MacKay 2009). It’s not the timing of
complete depletion that matters; it is the timing of peak production, which will be much sooner. For example,
coal production in Britain peaked in 1913, and since then its global influence has decreased.
In the US we have abundant coal. This combined with generous federal subsidies make coal the
cheapest form of energy. Using coal instead of oil can reduce US dependence on foreign oil and make us less
vulnerable to Peak Oil. However, coal is the dirtiest source of energy. It has the largest carbon footprint,
meaning it emits more CO2 per unit energy over its life cycle than any other energy source (see Table 7-4). Coal
burning releases more CO2 worldwide than any other human activity. It supplies 50% of electricity but releases
more than 70% of the electrical sector’s CO2 emissions ((Brown 2009), pg. 214). Coal burning also releases
toxic metals like mercury, sulphurous and nitrous oxides that contribute to acid rain, and particulates and
ozone that contribute to ground-level air pollution. In addition, coal mining (mountaintop removal, fly ash
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settling ponds, etc.) is very harmful to the environment. Adopting Carbon Capture and Storage (CCS)
technology would reduce CO2 emissions but would not solve all of the other problems associated with coal use,
and would also make coal much more expensive.
Coal companies are coming under increasing pressure as the public becomes aware of these problems,
and in classic corporate fashion are responding with an advertising campaign that makes a joke of the truth.
They respond by saying that coal is a clean fuel, when in fact it’s the dirtiest fuel available. If you have ever held
a piece of coal, perhaps on Christmas in a year you were “naughty,” you know that it is dirty. You touch it and
your hands turn black. If you burn it, you will see lots of dirty smoke, and when you finish burning it you will
have a pile of ashes. It’s very similar to charcoal: both form by partial oxidation (burning) of organic matter,
usually cellulose-rich plant material such as wood, and both are dirty.
In 18th century England where coal was the preferred fuel, a layer of black soot covered every exposed
surface. It was not coincidence that surgeon Percivall Pott discovered cancer in England then. He noticed that
chimney sweeps often had testicular cancer. This was because the sweeps, usually orphans pressed into hard
labor, were forced to take off all of their clothes so they could fit inside a chimney. They would climb the
chimneys naked to clean them, and black soot always covered their bodies, which eventually gave them cancer.
Clean coal is an oxymoron, similar to “healthy cigarettes,” which cause cancer just like coal. However, the most
dangerous effect of coal is not the pollution released when it burns, nor the fly ash that remains after burning;
it is the huge amount of CO2 it releases to the atmosphere.
Despite these problems, President Obama and many members of Congress are pushing for development
of “clean coal” technologies. Why? Because even with an all-out push to expand the use of non-renewable
energy and nuclear power, most countries will still get most of their energy from fossil fuels for the next few
decades. The US probably cannot reduce the energy derived from fossil fuels below 60% by 2030 (EIA 2010).
Consequently the IPCC, acknowledging that coal will remain an important source of energy, advocates the
development and use of CCS to reduce CO2 emissions from coal (IPCC 2007). So is it possible for coal to be an
environmentally friendly source of energy? Here we look in detail at three topics related to that question. We
will show that mountaintop removal causes serious environmental damage; that coal-fired power plants release
too much toxic heavy metal pollution and cause acid rain, but solutions exist to reduce the severity of these
problems; and that CCS can potentially eliminate greenhouse gas emissions from coal-burning power plants,
which would make coal a much more attractive source of energy.
Coal Mining: Mountaintop Removal
One problem associated with all forms of coal mining is that coal usually contains sulphide minerals
such as pyrite FeS2 that dissolve in water when exposed at the surface. This process makes the water acidic,
resulting in Acid Mine Drainage (AMD). Acidic water is very good at dissolving toxic heavy metals, so
AMD can mobilize these metals and transport them to locations where people can be exposed. Heavy metals
are also more bioavailable in acidic water, meaning plants more readily take them up before animals consume
them. Bioaccumulation occurs when contaminant input to an organism is faster than output so that the
concentration of the contaminant in the organism increases. Biomagnification causes the concentrations of
contaminants such as heavy metals to increase as they move up the food chain, that species at the top of the
food chain (e.g., humans) are exposed to the highest concentrations. Bioaccumulation and biomagnification
make the release of heavy metals to the environment during coal mining and burning a serious health risk.
We mine coal in a variety of ways. Coal beds are sedimentary layers that are often flat and flat-lying. If
the coal bed, or seam, is close to the surface, miners can strip off the overburden (rock layers above it), a
process called strip-mining. This approach is inexpensive, but if no one reclaims the land after mining it can
cause extensive environmental damage. Proper reclamation requires that miners cover the coal tailings and
exposed bedrock with soil and contour it to approximate the original land surface. Historically underground
coal mining was the most common coal mining practice, but strip mining and mountaintop removal mining
have superseded it because underground coal mining is very unsafe and expensive. Coal comes mostly from
strip mines in the western US and mountaintop removal mines in the eastern US.
In the Appalachian Mountains mountaintop removal is the preferred form of mining. It involves
piecemeal removal using dynamite of the parts of a mountain that overlie a coal seam. Only recently has our
society become aware of the extensive environmental and safety problems associated with mountaintop
removal. The main problem is that miners dump the overburden into stream channels, contaminating the
streams and blocking their flow. The first scientific study to evaluate the effects of Mountain Top Mining with
Valley Fills (MTM/VF) (Palmer, Bernhardt et al. 2010) concluded that it can cause permanent loss of
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ecosystems in the filled valleys; that the frequency and magnitude of floods downstream of mined areas
increase; and that valley fill can contaminate water and lead to decreases in stream biodiversity, even long after
mining ceases. Of particular concern is the mobilization of the heavy metal selenium (see section on heavy
metals), which was found at unsafe levels in 73 out of 78 surveyed streams (Palmer, Bernhardt et al. 2010).
Bioaccumulation and biomagnification of selenium have led to the publication of safety advisories that
recommend limiting consumption of fish caught in states such as Kentucky and West Virginia affected by
MTM/VF. Residents of MTM/VF affected areas have higher rates of mortality and of many health problems
compared with the general population, and post-mining mitigation has not been effective at reducing
environmental and health problems.
In 2009 the EPA said that it won't hold up applications for mountaintop removal for coal mining v. This
was a very disappointing development, as most environmentalists assumed that the Obama administration
would ban or severely restrict mountaintop removal mining. The administration probably realized that going
cold turkey is not practical, as coal supplies 50% of our electricity, and 15% comes from mountaintop removal vi.
The US does not yet have a substitute for coal obtained by mountaintop removal.
A recently recognized threat of mountaintop removal coal mining is the potential for terrorist attacks on
the huge storage ponds it creates at high elevations. Coal slurry ponds hold the waste produced by washing
mined coal. These ponds are usually located near the mountaintop removal mining site, at high elevations in
areas with high relief. Typically billions of gallons of toxic slurry are held by an earthen dam. These storage
ponds are inherently unstable. A small earthquake, a terrorist explosion, or most likely heavy rainfall, would
be enough to cause each dam to collapse and flood the underlying communities. Because the dams are usually
composed of soil, heavy precipitation can cause failure by saturating the dams with water, which would add an
enormous amount of weight and cause each dam to collapse under its own weight. These risks caused the EPA
to classify 44 storage ponds in 26 communities as high hazards, meaning that failure of the dams and
uncontrolled release of the slurry could cause death and significant property damage. As part of their
inventory efforts, they had planned to reveal the locations of the ponds publicly, but the Army Corps of
Engineers decided that the EPA should not reveal the locations because of national security concerns.
Dynamiting a dam could destroy underlying communities and cover large areas with toxic sludge. Recognizing
the potential for terrorist attacks, the Obama administration decided in early June of 2009 that it would not
release the locations of coal slurry storage ponds (they backpedaled on 6/30/2009). Clearly the practices of
MTM/VF and associated storage of coal slurry in mountainous areas are dangerous and unsustainable.
Residents of Appalachia are divided over whether to allow mountaintop removal mining to continue.
Those who have jobs with coal companies are unwilling to give them up. Yet mountaintop removal coal mining
and its associated lifestyle are unsustainable. The mines in their towns will be closed within a generation.
Sustainability means that they should give their children the same or a better lifestyle than they have. If they
can’t manage without coal mining, what do they expect their children to do? This is a serious social problem
with no easy answers.
Unfortunately many coal mining companies make no efforts to reduce the environmental and social
impacts of their activities. Perhaps the worst example of this in all of corporate America is Massey Coal. The
movie “Sludge” shows how a subsidiary of Massey, Martin County Coal, released 306 million gallons of coal
slurry into Wolf Creek in eastern KY in 2000, which contaminated local drinking water. A Martin County Coal
representative told residents that the slurry posed no health threats because everything in the slurry could be
found in the periodic table. Once the Bush administration took office they stopped the EPA investigation and
fired the lead investigator. They ordered Massey to pay a fine of only $110,000, which amazingly was later
lowered to only $5,500.
Coal companies will continue to break laws as long as the government punishes them only with
minuscule fines. Massey has routinely violated environmental regulations with impunity. By 2008 Massey
had accrued fines of roughly $2.4 billion for violations of the Clean Water Act; in 2008 it agreed to pay $20
million to the US EPA. Also in 2008 Massey paid $4.2 million in civil and criminal penalties resulting from a
mine fire in West Virginia in 2006, the largest financial settlement for a single event in the history of the coal
industry vii.
Recently Massey was involved in a lawsuit that reached the US Supreme Court. A competitor, Harman
Mining, refused to sell a coalmine to Massey, so Massey bought all of the property surrounding that mine and
prevented Harman Mining from entering their own property. Harman Mining sued Massey in court and won
$50 million, but Massey appealed it to the State Supreme Court. Massey’s chief executive Don Blankenship
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arranged donations of $3 million to get Brent Benjamin elected to the West Virginia Supreme Court of Appeals
(the $3 million was spent on a character assassination campaign against Benjamin’s opponent). When
Massey’s appeal made it to the Court of Appeals Benjamin refused to recuse himself from the case, and cast the
deciding vote in favor of Massey. Harman Mining appealed to the US Supreme Court, which ruled on June 8,
2009 that Benjamin’s refusal to step aside deprived Harman Mining of the constitutional right to a fair
hearing, thus restoring Harman Mining’s $50 million claim against Massey. It seems that their chronic
disregard for the law finally caught up with Massey, as competitor Alpha Natural Resources bought the
company for $7.1 billion in 2011. Yet it hardly seems that justice was served, as Don Blankenship is retiring as a
multimillionaire when he should be in jail.
Coal will not be a safe, environmentally friendly energy source until the government bans the use of
MTM/VF and coal slurry ponds. Environmentally friendly methods of mining and disposal exist, but they cost
more. Coal companies have externalized the environmental and social costs of coal mining, which has kept
coal as the cheapest source of energy in the US. Until Americans start to pay the true cost of coal, they will
continue to destroy communities in Appalachia, and the remaining communities will face the risk of
catastrophic floods from failure of slurry ponds.
Mountaintop mining in eastern Kentucky
In October 2010 I traveled to eastern Kentucky to learn about the effects of MTM on the
community. We were fortunate to be able to tour an ICG coal mine in Hazard, KY, and to meet with
some prominent opponents of MTM, including Tom Fitzgerald, director of the Kentucky Resources
Council, and Erik Reece, author of "Lost Mountain." Most of the community clearly supported coal
mining, but a vocal minority of opponents included people like Beverly May who had to fight coal
companies to save their homes. After saving her neighborhood from MTM, Beverly became an
activist with Kentuckians for the Commonwealth and was featured in the documentary "Deep
Down." Her story made me wonder if coal supporters would become opponents like Beverly if coal
companies threatened their homes. Why are people willing to let corporations destroy their
neighbors’ homes and write it off as "progress?" The devastating effects of MTM became apparent
when we toured the property of Daymon Morgan, an army veteran who has been fighting for decades
to prevent a coal company from destroying his land. Because he is too old to walk through his
forested backyard, he hopped in his ATV to take us for a tour. He showed us the herbs and trees that
grow in the wild. Then he took us over the ridge to see his neighbor's property: it was a bald patch of
rock and dirt, with rubble strewn along its length. The contrast between Daymon's beautiful forest
and the ugly coal mine was so overwhelming that a student started crying.
Traveling through Hazard, KY made me realize the scale of MTM. When I started teaching
Geology, I would tell amazed students that the 1980 eruption of Mt. St. Helen blew 1300 feet of rock
from its top. In Hazard alone I must have seen ten mountains that had that much rock removed from
their tops. Humans have exceeded nature in destructive capacity.
Perhaps we could live with MTM if coal companies returned mine tailings to their original
location at the top of the mountain rather than dumping them into stream valleys where they
contaminate the water. If coal companies restored the land surface to its "approximate original
contour" and then replaced the soil and planted new trees, the environmental and aesthetic
objections would mostly disappear. However, coal companies insist on using the cheapest mining
methods, and don't view "restoring the land" as part of their job. Thus, they continue to turn much
of Appalachia, one of the most beautiful areas I've ever seen, into a wasteland. For more information
see "Leveling Appalachia: The Legacy of Mountaintop Removal Mining."
Coal Burning: Toxic Heavy Metals, Acid Rain, and Fly Ash Retention Ponds
Coal contains sulphur and nitrogen, and releases them to the atmosphere as sulphur and nitrous oxides
during burning. These oxides react with water in the atmosphere to form sulphuric and nitric acids. These
strong acids can decrease the pH of rainwater to values below four (Langmuir 1997). Acid rain has caused
serious ecological damage in areas such as New England that are downwind from many coal-fired power
plants. Acid rain has made 6% of lakes in New England uninhabitable for many species of minnows. Sulphur
emissions have been greatly reduced by an emission trading system (cap and trade) established by Congress in
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1990 as an amendment to the Clean Air Act. This has provided power utilities with a strong incentive to use
low-sulphur coal and to install scrubbers that remove sulphur oxides from the exhaust air in smoke stacks.
Coal also contains radioactive and toxic elements. It contains trace amounts of the naturally-occurring
radioactive elements uranium and thorium. These elements get concentrated in the fly ash produced during
burning. Most of the fly ash is recovered for disposal, but some escapes to the atmosphere, exposing people
who live downwind of the plant to low levels of radiation viii. In fact, coal-fired power plants expose people to
higher levels of radiation than nuclear power plants (McBride, Moore et al. 1978). The toxic heavy metals
mercury, arsenic, and lead also become concentrated in fly ash. Around 1,300 coal-fired power plants across
the US collectively emit some 50 tons of mercury annually into the air, the largest single source of mercury
emissions to the air in the US ix. Mercury is the most toxic naturally occurring element: it is a neurotoxin and it
biomagnifies in the food chain, reaching its highest levels in a mother’s breast milk, which puts mothers and
infants at greatest risk. The Environmental Protection Agency agreed to set new rules to decrease emissions of
mercury, soot, and other chemicals from coal-fired power plants by Nov. 16, 2011 x.
The radioactive and toxic elements contained in coal are concentrated in the fly ash collected from coalfired power plants. Unfortunately the EPA does not regulate the disposal of fly ash. As a result, coal companies
dispose of it using the cheapest method possible: they simply dump it as a water slurry into holding ponds
enclosed by earthen dams. These fly ash retention ponds are disasters waiting to happen. A pond behind the
Kingston coal-fired power plant in eastern Tennessee collapsed on December 22, 2008, releasing 1.1 billion
gallons of coal fly ash slurry. The largest fly ash release in US history, it covered up to 300 acres in a layer of
toxic coal fly ash sludge up to 6 feet thick xi. The cleanup will take years to complete and will cost the Tennessee
Valley Authority (TVA) near $1 billion. We can guess that there are roughly as many coal fly ash slurry ponds
that will eventually collapse as there are coal-fired power plants in the US, about 1300.
Carbon Capture and Storage
Carbon Capture and Storage (CCS) aims to eliminate the release of the greenhouse gas carbon dioxide
from the smokestacks of coal-burning power plants. The US is relying on the still undeveloped technology of
CCS to make coal-burning power plants "clean” by capturing and storing all of the CO2 underground. CCS
holds promise for mitigating AGW. However, it will make coal-produced electricity much more expensive and
take decades to set up on a large scale. Furthermore, CCS alone won't make coal clean because it doesn't solve
many other problems associated with coal mining, burning, and waste disposal.
The US government's first effort to develop the technology was the FutureGen Industrial Alliance,
which aimed to construct a pilot plant to test coal gasification, hydrogen production, and CCS technologies. The
Bush administration promoted FutureGen for years until it abruptly killed it in 2007, claiming that rising costs
made it unaffordable. The administration made its decision one month after the Alliance chose an Illinois
location for the plant over the two competing locations in George Bush's home state of Texas. This gives you
some idea of why the US made so little progress in energy technology during the Bush administration: they
based decisions only on politics (see the discussion of corn-based ethanol below as another example). The
FutureGen project was modified and restarted as FutureGen 2 in August 2010.
CCS has several problems. First, it is energy-intensive, meaning that power plants with CCS must burn
20-44% more coal to generate the same amount of electricity (Viebahn, Vallentin et al. 2009). Second, largescale application of CCS technology is unlikely before 2020. If the US expands the use of coal, it will build
many coal-fired power plants within the next decade before CCS technology is available (Viebahn, Vallentin et
al. 2009). Third, it is costly. Adding CCS to a coal-fired power plant would increase the cost of electricity
produced by 50%. Fourth, better alternatives to fossil fuel CCS plants exist; greenhouse gas emissions for
electricity produced by solar, thermal, and wind are only 2-3% of emissions from fossil fuel CCS plants
(Viebahn, Vallentin et al. 2009). And many unanswered questions remain: Where would we inject the CO2,
given the anticipated NIMBY (Not In My Back Yard) objections? What is the probability of it escaping, perhaps
explosively, after injection? Who would be liable if this happened? CCS may not be a panacea.
However, given that expansion of non-renewable energy sources cannot keep pace with demand, it
makes sense to try to make abundant coal a cleaner energy source. We are making progress: American
Electric’s Mountaineer Power Plant is the first plant in the world to use CCS. Scrubbers at the plant remove
98% of sulphur dioxide emissions and 90% of nitrogen oxides (Biello 2010). Although they capture only 2% of
CO2 emissions, the project represents “proof of concept,” and they plan to expand the CCS capacity. Power
utilities are already building more plants with CCS, including the resurrected FutureGen plant and plants in
France, Germany, and China. Many other CCS plants are in the planning stages (Biello 2010). Although these
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projects cost billions of dollars and may double the cost of coal-produced electricity, companies are moving
forward in anticipation of binding CO2 emissions standards resulting from an international climate change
agreement.
Expanding the use of coal without CCS and mining reform would be the biggest mistake the US could
make. Conventional coal use leads to mountaintop removal, pollution, failure of coal slurry retention ponds
(e.g., Martin County, KY 2000) and fly ash retention ponds (e.g., Kingston, TN 2008), and maximum CO2
emissions and global warming. Scientists like well-known Climatologist James Hansen have become so
concerned about this possibility that they have dropped their impartiality and have become anti-coal activists.
Police arrested Hansen on June 23, 2009 for blocking a highway in front of a West Virginia coal plant. Several
states have already banned the construction of new coal-fired power plants. Until banning mountaintop
removal mining and the construction of power plants without CCS makes coal truly clean, the US must make
every effort to decrease conventional coal use and to replace coal with sustainable, renewable, nonpolluting
energy sources.
See Clean Coal Air Freshener parody: http://www.youtube.com/watch?v=W-_U1Z0vezw
Clean Coal: http://www.youtube.com/watch?v=PLZ-hvVVGmY&NR=1
The True Cost of Coal
It should be obvious by now that the true cost of coal is much greater than the market cost. If we use
Full Cost Accounting to calculate the true cost, which includes the loss of social and environmental capital,
incorporates the social. Recently the US National Research Council (NRC) published a report in which they
estimate the external costs of energy sources (USNRC 2010). Making the hidden costs of energy production
public may spur policy changes that correct the failure of the market to produce accurate price signals. The
NRC used LCA to evaluate external costs and benefits related to health, environment, security, and
infrastructure for each type of power production over its entire life cycle. Because it had been previously
identified as a large external cost, the NRC focused on air pollution, especially the effects of emissions of
particulate matter (PM), sulfur dioxide (SO2), and oxides of nitrogen (NOx). They found that most external
costs were related to health, particularly premature mortality. In part this finding resulted from a lack of data
to assess the external costs resulting from loss of ecosystem services or nongrain agricultural crops. Most
external costs are incurred during fuel use, i.e., during electricity production. Damages resulting from
emissions of PM, SO2, and NOx from coal-fired power plants in 2005 amounted to roughly $62 billion, or $156
million on average per plant (USNRC 2010). These external cost estimates do not even include the effects on
global warming, which the NRC treated separately due to large uncertainties. Ten percent of the plants
produced 25% of net generation and accounted for 43% of the damages. The average damage is 3.2¢ per kWh,
which added to the current economic cost of about 3¢ per kWh more than doubles the price of coal, making it
more expensive than any other form of energy. Five percent of the plants have non-climate related damages
greater than 12¢ per kWh. Plants with the highest external costs per unit of power generated should be
targeted for early closing. Options include converting them to biomass- or waste-burning facilities. The latter
is particularly attractive because it reduces the need for landfill space.
Table 1-5: Fuel Sources Used to Produce Electricity*
Electricity
Source
Current
supply
Current
Current Cost Pros
Cost
(per KWh)#
(per KWh)*
Cons
Coal
49%
3¢
< 1¢
Domestic supply
Highest GHG
emissions,
coal mining, air
pollution
Natural gas
20%
4.7¢
3¢
Least land required; Clean;
Mostly domestic supply
GHG emissions,
drilling
Nuclear
19%
3.3¢
No GHG emissions associated
with use;
Domestic fuel supply
Radioactive waste;
Uranium mining and
transport
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< 1%
3.4¢
No emissions
No fuel or water consumed
Solar PV
38¢
CSP
12-18¢@
Intermittent supply
Can be far from
customers
* (Wald 2008), after US Energy Information Administration
# http://greenecon.net/understanding-the-cost-of-solar-energy/energy_economics.html
@ http://www.businessworld.in/bw/2009_09_14_Google_Plans_New_Mirror_For_Cheaper_Solar_Power.html
Now we know that the true cost of coal is greater than that of any other type of fuel. Americans will save
large amounts of money and be safer and healthier if the US phases out coal-burning power plants as quickly as
possible.
Natural Gas
Natural gas consists primarily of methane plus minor amounts of other light hydrocarbons. It is
associated with oil because it forms from similar material through similar processes. When oil is buried deeper
than the oil window, it transforms at the higher temperatures to natural gas. The associated oil and gas rise
until they become trapped by an impermeable layer. The less dense gas often rises above the oil, so when a drill
penetrates the overlying impermeable layer the gas is released explosively. This process caused the Deepwater
Horizon disaster. Methane that escapes to the atmosphere is considered a pollutant and is a potent greenhouse
gas. It has a half-life of only seven years in the atmosphere because it reacts with atmospheric oxygen to form
CO2 and water.
Natural gas is considered a “clean” fossil fuel because burning it emits less CO2 and sulphur per unit
energy than other fossil fuels, so it causes the least environmental damage than coal or oil. It is the fuel most
commonly used for heating. Worldwide natural gas provides 21% of TPES and 20% of greenhouse gas
emissions (Table 7-2). It is an efficient and safe fuel for automobiles, with an octane rating of 135 (Deffeyes
2001). Worldwide there are about 10 million autos fueled by natural gas. Natural gas can also be used to
produce hydrogen for use in autos with hydrogen fuel cells. Natural gas is also used to synthesize ammonia for
use in fertilizer production. For these reasons, energy experts expect natural gas to fill the gap during the
transition from coal and oil to sustainable renewable energy sources (Meadows, Randers et al. 2004).
Natural gas can be obtained from sources other than oil fields. Sediments on the continental shelf
contain large volumes of methane stored in clathrates or “methane ice.” However, we have yet to develop a safe
method for extracting natural gas from these deposits. Most biofuel production methods transform biomass to
natural gas through bacteria-mediated anaerobic decay. The same processes occur in swamps and landfills,
where bacteria obtain energy by catalyzing the breakdown of heavy hydrocarbons to form methane (swamp
gas). Decomposition of organic material in landfills and sewage also produces methane. Landfills used to burn
off produced methane to prevent explosions, but it becoming more common for landfills to recover it for use as
a fuel. Similarly, sewer treatment plants in large cities such as Los Angeles and New York City are starting to
recover produced methane and use it to produce electricity.
Hubbert (1956) used his empirical method to create a resource production curve for natural gas in the
US. Roger Naill (1973) used a system dynamics model to do the same. Although the approaches were very
different, the results were similar: nearly Gaussian-shaped production curves that peaked in the early- to mid1970s, consistent with what was observed. Numerous system dynamics studies of fossil fuel production have
confirmed the accuracy of the Hubbert approach for estimating peak production xii. However, exploration in the
US and worldwide has since uncovered large natural gas reservoirs, and improved drilling and recovery
technologies like hydrofracking have further increased natural gas reserves. Technology improvements have
roughly doubled natural gas reserves since Hubbert made his first prediction, and unlike oil, deeper drilling
may discover more (unlike oil, natural gas is not restricted in depth to a "window"). In North America
estimates of Peak Gas range from 2001 to 2013. Globally we have a larger global reserve of natural gas than oil,
enough to last 100 years at current rates of consumption (Deffeyes 2001). Russia has the largest natural gas
reserves, followed by Iran and Qatar.
One downside of natural gas is that it takes up more volume than liquid oil and gasoline, making it
more expensive to transport. Currently natural gas is transported under pressure and is highly flammable,
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which may result in dangerous explosions and fires. Another controversy has opened up about the
environmental safety of the process of hydrofracking, which is now commonly used to extract natural gas from
impermeable rocks, usually shales, at depths from 2500 to 4000 feet. Water and chemicals are injected under
very high pressure to fracture the underlying impermeable rocks, making them permeable so that natural gas
can be extracted. The movie “Gasland” released in 2010 and nominated for an Academy Award for best
documentary brought the dangers of this process to the public’s attention. Much of the concern centers on the
use of proprietary chemicals that mining companies inject into the subsurface to lubricate and prevent
corrosion during the natural gas extraction process. These chemicals, which the mining companies refuse to
identify, can potentially contaminate groundwater supplies, and some well owners in Pennsylvania near
hydrofracking sites claim that the process has contaminated their water supplies. Ironically, the mining process
is exempt from regulation under the Clean Water Act.
Roughly five hundred power plants in the US use natural gas to produce electricity. External nonclimate related damages from natural gas fuelled power plants from from emissions of SO2, NOx, and PM in
2005 amounted to roughly $740 million (USNRC 2010). The external costs per kWh were much lower than for
coal, with an average of 0.16¢ compared with 3.2¢ for coal (USNRC 2010). We conclude that because it is a
relatively clean-burning fossil fuel, use of natural gas is preferable to coal. However, prices of natural gas will
continue to rise since we are at or near the peak of global production. Use of natural gas as an energy source
should eventually be phased out to mitigate AGW unless it employs CCS to eliminate emission of CO2 produced
during burning.
Nuclear Power
“And Lord, we are especially thankful for nuclear power, the cleanest, safest energy source there is.
Except for solar, which is just a pipe dream.” – Homer Simpson, The Simpsons
Nuclear power is an important energy source. Worldwide, 440 nuclear reactors produce 16% of global
electricity needs and about 20% of electricity in the US (Wallace 2005). Worldwide it produces 6% of TPES
(Table 7-2). However, in the US nuclear power has always been a controversial energy source. Opposition is
based on safety concerns, the lack of long-term options for storage of radioactive waste from nuclear reactors,
and the high costs of power plants. As a result, nuclear power plant construction came to a standstill in the
1980s. However, recent concerns about AGW have renewed interest in nuclear power. Nuclear power plants
do not emit CO2, making them an attractive option for mitigating AGW.
Historical data and modeling show that nuclear (along with wind) is the safest form of energy, with the
lowest death rate per unit energy of all forms of energy ((MacKay 2009); (OECD and NEA 2010)). Planned 3rd
generation mini-power plants are even safer. However, concerns about lack of storage facilities for nuclear
waste continue. The recent nuclear disaster in Japan has also called the safety of nuclear power plants and the
practice of storing nuclear waste in pools on-site into question. We will examine the pros and cons of nuclear
power in detail.
Uranium Supply
Nuclear energy comes from the nuclei of atoms. In atoms the nucleus stores nuclear energy and the
electrons store chemical energy. The nucleus contains more than one million times more energy than the
electrons, so the mass of fuel and waste for nuclear energy is about one million times smaller than for sources
of chemical energy such as fossil fuels (MacKay 2009). For example, 2 g of natural uranium in a fission
reactor produces the same amount of energy as 16,000 g of fossil fuels, and the proportions of waste produced
are similar. This gives nuclear energy a distinct advantage; MacKay (2009) believes that the volume of waste is
so small that “nuclear waste is only a minor worry, compared with all the other forms of waste we are inflicting
on future generations.”
Atoms with medium-sized nuclei are the most stable, i.e., they have the lowest energy per unit mass.
Thus, splitting a large nucleus, such as that in uranium, into several medium-sized nuclei releases large
amounts of energy. The products of a nuclear fission weigh less than the reactants, and the difference is the
mass converted to energy according to Einstein’s famous equation E=mc2, where c, the speed of light, is a very
large number.
Most of the energy produced in nuclear power plants comes from the fission of an isotope of Uranium
235 U, where 235 is the atomic mass (the number of protons plus neutrons in the nucleus) and 92 is the atomic
92
number (the number of protons in the nucleus). This isotope makes up 0.7% of natural uranium, but we must
enrich it to 3% before we can use it as fuel in a burner reactor.
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Uranium is not a renewable resource. The peak in global uranium production occurred in 1980 (Vance
2006). Yet the most recent and comprehensive report estimates that more than 100 years supply exists at
2008 rates of consumption, and that even if consumption grows rapidly, we would consume less than half the
identified resources by 2035 (OECD 2010). However, 100 years supply from land mines does not qualify
traditional nuclear power as a sustainable energy source. For example, Mackay (2009) regards one thousand
years supply of a resource as a minimum to be considered sustainable. On the other hand, extraction of
uranium from seawater could greatly increase the supply of fissionable uranium. MacKay (2009) calculates
that seawater extraction of uranium used in inefficient “once-through” fission reactors could globally produce 7
kWh per day per person for 1600 years (the overturn time of oceanic circulation). Using fast breeder reactors
that are 60 times more efficient than once-through reactors would increase that to 420 kWh/d per person,
more than even Americans consume (MacKay 2009). Thus, nuclear fission could be a significant source of
sustainable energy.
Nuclear Reactors
Nuclear burner reactors include a core, control rods, coolant, and reactor vessel xiii. In the reactor
neutrons smash into 235U atoms, splitting them apart and releasing energy. This also releases neutrons that
can split other atoms. Control rods absorb neutrons and moderate the rate of reaction, allowing the nuclear
“chain reaction” to continue at a constant rate. Nuclear fission releases energy primarily as heat, which power
plants use to boil water. The resulting steam flows upward and pushes the blades of a turbine hooked up to an
electrical generator. In the famous Chernobyl accident operators pulled the control rods too far out of the
reactor, causing 235U nuclei to fission too fast. This increased the temperature until the fuel became so hot that
it melted through the bottom of the containment vessel, the only full “meltdown” that has ever occurred. In
contrast to nuclear power plants, nuclear bombs initiate an uncontrolled, runaway fission process that
suddenly releases a huge amount of energy. Fortunately, nuclear explosions are not possible in nuclear power
plants.
Designs for US nuclear power plants are not optimal or standardized, making power plants expensive to
build and maintain. For example, France has only one nuclear power plant design, which decreases the cost
per unit through economies of scale. Every power plant in the US is different, meaning that each plant has
been custom-built at great expense, and whenever a part breaks a replacement part must be custom-fabricated
at great cost. If the US chooses to start building new nuclear power plants, it should settle on a single, optimal
design to reduce costs and increase safety and efficiency.
Adopting new third-generation “mini” nuclear reactors would partially or completely solve problems
associated with nuclear power production xiv. The new mPower nuclear plant is a 125-megawatt reactor that is
about 10% of the size of older plants and can provide electricity for about 100,000 homes. Decentralizing
nuclear power production by building many small reactors rather than a few large reactors more evenly and
fairly distributes the risk, making it more equitable. Also, it reduces line transmission loss and the need to
build high-capacity transmission lines. The manufacturer, Babcock and Wilcox Company, claims that “each
mPower reactor that is brought online will contribute to the reduction of approximately 57 million metric tons
of CO2 emissions over the life of the reactor. xv” Furthermore, throughout its projected 60-year lifespan it would
store the SNF in underground pools, at least temporarily negating the need for transportation and storage at a
centralized location. Older plants thermally polluted rivers by releasing their cooling water downstream, but
the new reactors would be primarily air-cooled. Placing the containment structures underground would
increase safety. Thus, the new generation of nuclear power plants may solve many problems that have plagued
the industry in the past. The TVA hopes to finish construction of the first of these plants by 2018.
Obstacles to the Expansion of Nuclear Power
Several obstacles prevent growth of nuclear power in the US. First, a large part of the public resists
expansion of nuclear power because they fear all things nuclear. Nuclear power will always be associated in
people’s minds with the use of nuclear bombs in WWII and the fear associated with proliferation of nuclear
warheads during the Cold War and the accidents at Three Mile Island and Chernobyl. Furthermore,
radioactivity is particularly frightening to people because it is invisible and outside their normal experience.
Fear makes people irrational, and as a result, I have never convinced any opponents that nuclear power is safer
than other forms of energy, though I have the statistics to prove it. Despite the fear it invokes, nuclear power
has a remarkable safety record in the US. The only significant nuclear power plant accident ever in the US was
the Three Mile Island accident in central Pennsylvania in 1979, a minor accident that released very little
radioactivity into the environment. Producing electricity with a nuclear reactor is one of the safest activities in
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which our society engages. An individual living near or working in a power plant faces far less risk if it is a
nuclear plant rather than a coal-fired power plant. Even the levels of radiation exposure near power plants are
higher for coal-fired than nuclear. Individuals face far less risk living near a nuclear power plant than driving a
car, walking along a street, smoking, bicycling, or swimming. Environmentalists argue that accepting the risks
associated with nuclear power plants is illogical, but many of them choose to buy and smoke marijuana, which
is far riskier for both the individual (lung cancer, accidents caused by slowed motor response) and society
(thousands of people killed, many of them innocent, in the Mexican drug wars in 2010). Furthermore,
historical data (MacKay 2009) and probabilistic safety assessments considering both immediate and delayed
fatalities (OECD and NEA 2010) show that nuclear power is much safer than coal power. We conclude that
substituting a nuclear reactor for a coal-fired power plant with the same production capacity would save lives.
So opposition to nuclear power based on its safety record is illogical.
The most important obstacle to growth of nuclear power in the US is that we have no site to store the
radioactive Spent Nuclear Fuel (SNF) from fission reactors. For these reasons, no electric utility companies
applied to the Nuclear Regulatory Commission for a license to operate a new nuclear power plant for more than
20 years. However, the recent recognition of the need to reduce CO2 emissions has reopened the debate:
should we expand the use of nuclear power in the US? Nuclear reactors do not emit CO2 or any other
pollutants, giving them a decided advantage over fossil fuel-powered plants. When we consider the entire
uranium fuel cycle, we find that mining uranium and producing fuel rods consumes fossil fuels and emits CO2.
Though estimates vary widely, the carbon footprint of nuclear power is far lower than all fossil fuels (Table 74). Moreover, if we start to tax energy produced by burning fossil fuels, then nuclear power may become
economically competitive. Proposed cap and trade programs to reduce CO2 emissions would make nuclear
energy more economical by internalizing the social cost of carbon emissions, which would increase the
economic cost of fossil fuels. With the renewed interest in nuclear energy there are now two dozen applications
pending for new nuclear power plants. However, several questions remain unanswered. Can the US choose a
site and build a facility for storage of SNF? If not, is the current industry practice of storing spent nuclear fuel
(SNF) on-site in pools safe? And would nuclear energy still be cost-effective if we include the cost of waste
disposal?
The answer to all of these questions may be no. After the federal government spent $13.5 Billion
developing a high-level nuclear waste disposal site at Yucca Mountain, about 100 miles northwest of Las Vegas,
Nevada, newly elected President Obama announced that the government was abandoning the project xvi. When
reporters asked the President’s science advisor why, after waffling for several minutes he finally said, “We can
do a better job.” Considering that our country spent more than 30 years developing the Yucca Mountain site,
and that 30 years later finding a site that is acceptable to all parties will be even harder (the NIMBY syndrome),
I am not holding my breath. The Yucca Mountain project fell victim to politics. Senate majority leader Harry
Reid represents the southern part of Nevada that includes Yucca Mt., where resistance to the project has always
been strong, and he followed through on his vow to kill the project.
Even if the US had followed through, the Yucca Mountain facility would not have been large enough to
accept all of the waste we would have produced by the time it opened. The US currently has 103 operating
nuclear power plants (Wallace 2005). By law, the capacity of the Yucca Mountain facility was limited to 70,000
tons, of which 63,000 tons were designated for SNF and 7,000 tons for defense waste. However, estimates are
that by 2050 the US will have 84,000 tons of SNF (Carter and Pigford 1998). The US now has SNF at more
than 100 sites in 42 states (Long and Ewing 2004), and we have now eliminated our only option for safely
disposing of it. The federal government now pays large annual fines to the utility companies for breach of
contract: they had promised to take the SNF off the hands of the utility companies by now, but utilities still
store SNF at every nuclear plant.
One possible solution to the SNF problem is to use breeder reactors that reprocess the fuel, which is 60
times more efficient than the once-through reactors we currently use. Recycling the waste sounds like a good
choice from an environmental standpoint, as it would reduce how much SNF must be disposed of and the
required amount of environmentally harmful Uranium mining. However, breeder reactors are very expensive
and difficult to operate. Also, they produce plutonium, which raises risks associated with waste disposal and
proliferation of material that can be used to make atomic bombs.
If in the future we build a centralized storage facility, the waste will be so radioactive that by law we will
have to monitor it for one million years. According to Kellogg and Pettigrew (2008), “The energy needed to
run even so much as a light bulb, let alone a full security operation guarding spent fuel, for the duration of
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nuclear waste’s radioactivity would rival that of all the energy ever produced by all of the world’s nuclear power
plants combined.” Thus, they argue, uranium fuel production and waste disposal would consume far more
energy than fission reactors produce, making the EROEI of nuclear power less than one, which would mean
that nuclear power is an unsustainable form of energy. However, this argument fails to take into account the
economic and technological benefits of producing power today, which is an investment that spurs economic
growth and may lead to the development of new energy-producing technologies. Like other investments, the
benefits are compounded over time, so over a million years the economic returns would dwarf the cost of
operating a light bulb for one million years. Furthermore, the argument shifts the timeframe for decisionmaking to a million years, while our sustainability-driven decision making operates on a timescale of hundreds
to thousands of years. So the energy produced by fission reactors today is worth the energy used to ensure safe
storage of waste in the future.
A problem associated with nuclear power in the past has been that it is highly centralized, with a few
large power plants. Plans for waste disposal have been even more centralized, with the goal to store all of the
nation’s waste in one site, originally at Yucca Mountain. This leads to an unequal geographic distribution of
risk, and the resulting lack of equity has led to large-scale opposition to nuclear power. The equitable,
sustainable solution would be to decentralize nuclear power production and waste disposal.
Nuclear power suffered another setback when the M 9.0 earthquake struck northern Japan March 11,
2011, generating a 30 foot high tsunami that washed away everything for ~1/2 mile inland and that damaged
several nuclear power plants. At least three nuclear reactors lost cooling water due to damaged pumps or
ruptured pipes, and three reactors suffered partial meltdowns with releases of large amounts of radiation to the
environment. One reactor had two hydrogen explosions that occurred when the zirconium casings on the fuel
rods heated to temperatures > 2200°F and reacted with water to produce H2 gas, which exploded when it came
into contact with atmospheric oxygen.
The nuclear disaster in Japan has highlighted the dangers associated with on-site storage of SNF in
pools. SNF recently removed from reactors is even more radioactive than the fuel inside the reactor (due to
production of short-lived isotopes such as 137Cs, 131I, and 90Sr in the reactor) but has no protective container
surrounding it like the reactor fuel, which is encased in 6 inch-thick steel walls. The pools at several nuclear
plants lost their cooling water, so the SNF is heating up. Experts believe that if the SNF reaches high enough
temperatures, the zirconium casings could ignite and cause an explosion that would strew radioactive materials
over large areas xvii. Zirconium casings in the SNF pool of the Unit 4 of the Fukushima Dai-chi complex already
caught fire. The SNF rods could completely melt down if water is not returned to the pools soon xviii. Experts in
the US have been calling for a safer form of SNF storage called dry-cask storage xix, but only 25% is stored this
way because it is more expensive than pool storage xx. Even when dry-cask storage is used, SNF must first cool
off in pools for 5-8 years after being removed from the reactor before they can be transferred to casks.
These problems will likely strongly increase resistance to the construction of new nuclear power plants
in the US, especially in areas like the west coast that are vulnerable to major earthquakes and tsunamis.
Nuclear power plants are very safe under normal operating conditions, but natural hazards can make them
become very dangerous. Once again, the precautionary principle applies: we did not anticipate an earthquake
and tsunami of the magnitude seen in Japan in March 2011. Now we realize that nature can destroy any
safeguard system we devise. It is safer to rely on renewable sources of energy like solar and wind because they
do not use hazardous materials that can endanger people during extreme events. Americans have had the
hubris to build a nuclear power plant on the San Andreas fault. Doubtless the engineers who designed it
thought it could handle anything nature could dish out. Maybe now we will give nature a little more respect by
not placing inherently dangerous facilities in areas prone to extreme hazards, or better yet, by not building
them at all.
Republicans are now strongly pushing for the expansion of nuclear power in the US. They are trying to
restart the process for establishing Yucca Mountain, Nevada as the nation's high-level nuclear waste repository.
This would make sense if they had exhausted all of the more attractive options, but they rarely mention solar
and wind, and when they do, they usually dismiss them as inadequate sources of energy. Many smart people
have already determined that the US can meet its energy needs with solar alone (see Chpts. 8 and 9). In the US
renewable energy sources are limited not by thermodynamics, but by a lack of political will. Why try to ram
nuclear power down the throats of the many people who are strongly opposed to it, when we have better
options that no one objects to xxi?
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Summary
So what are the advantages of nuclear power plants? They have near-zero CO2 and pollutant emissions,
the supply can last more than one thousand years if we use breeder reactors or extract uranium from seawater,
and nuclear energy is safe compared with other forms of energy production. What are the disadvantages? The
nuclear fuel cycle releases small amounts of radiation to the environment at every stage. Nuclear reactor
accidents pose a very small but real risk. Terrorists or hostile countries could steal enriched uranium destined
for fission reactors or plutonium from breeder reactors to make nuclear bombs. The US has no permanent
SNF disposal facilities, and won’t have any for at least twenty more years. Finally, nuclear power is not costeffective: electricity generated using nuclear fission reactors is more expensive than electricity produced using
natural gas or coal (Table 7-5). However, as noted previously, including externalized costs makes coal power
more expensive than nuclear power.
Nuclear power is a very complicated, expensive, centralized form of energy production that requires
much government involvement (regulation and oversight), has a very vocal but shrinking opposition, and big
potential problems. Decentralized, renewable energy sources pose fewer risks and may be more cost effective.
Because it can theoretically obtain sufficient energy from safer renewable sources alone, the US should start
building new nuclear power plants only if an all-out effort to rapidly build new renewable power plants
nationwide and to decrease demand through conservation and efficiency measures fails to satisfy our energy
needs. However, we will show below that in many countries and regions, primarily those with high population
density and insufficient available land such as Japan and Europe, low-energy density renewable energy sources
cannot provide enough energy to meet current energy needs. In those cases relying on nuclear energy would be
better than coal.
Conclusions
The many problems caused by coal mining and burning earn it a spot in the ABCs of unsustainability:
autos and airplanes, beef, and coal. Coal is the least preferred energy source, followed by oil and natural gas.
Nuclear power should only be used in cases where safer renewable energy sources are inadequate. We will take
a detailed look at sustainable energy production in Chpt. 8, and sustainable energy consumption and policy in
Chpt. 9.
Brown, L. (2009). Plan B 4.0: Mobilizing to Save Civilization. New York, NY, W.W. Norton & Co., Inc.
Carter, L. J. and T. H. Pigford (1998). "Getting Yucca Mountain Right." The Bulletin of the Atomic Scientists
March/April.
Cho, A. (2010). "Energy's Tricky Tradeoffs." Science 329(5993): 786-787.
http://www.sciencemag.org/cgi/content/summary/329/5993/786.
Deffeyes, K. S. (2001). Hubbert's Peak: The Impending World Oil Shortage. Princeton, New Jersey, Princeton
University Press.
EIA (2010) "Annual Energy Outlook 2010." www.eia.doe.gov/oiaf/aeo/.
Friedman, T. (2008). Hot, Flat, and Crowded: Why We Need a Green Revolution - and How It Can Renew
America, Farrar, Strauss and Giroux.
Hertwich, E. G. and G. P. Peters (2009). "Carbon Footprint of Nations: A Global, Trade-Linked Analysis."
Environmental Science & Technology 43(16): 6414-6420. http://dx.doi.org/10.1021/es803496a.
Hubbert, M. (1956). "Nuclear Energy and the Fossil Fuel." Drilling and production practice.
IPCC (2007). Climate Change 2007: The Physical Science Basis. Contribution of Working Group I to the Fourth
Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, U.K. and New York,
NY, USA, Cambridge University Press.
Kellogg, S. and S. Pettigrew (2008). Toolbox for Sustainable City Living. Cambridge, MA, South End Press.
Langmuir, D. (1997). Aqueous Environmental Geochemistry. Upper Saddle River, NJ, Prentice Hall.
Long, J. C. S. and R. C. Ewing (2004). "YUCCA MOUNTAIN: Earth-Science Issues at a Geologic Repository for
High-Level Nuclear Waste." Annual Review of Earth and Planetary Sciences 32(1): 363-401.
http://arjournals.annualreviews.org/loi/earth.
MacKay, D. J. C. (2009). Sustainable Energy - without the hot air. Cambridge, England, UIT Cambridge Ltd.
www.withouthotair.com.
McBride, J. P., R. E. Moore, et al. (1978). "Radiological Impact of Airborne Effluents of Coal and Nuclear
Plants." Science 202(4372): 1045-1050.
http://www.sciencemag.org/cgi/content/abstract/202/4372/1045.
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Meadows, D. H., J. Randers, et al. (2004). Limits to Growth: The 30-Year Update, Chelsea Green.
Naill, R. (1973). The discovery life cycle of a finite resource: A case study of US natural gas. Toward Global
Equilibrium: Collected Papers. D. H. Meadows and D. L. Meadows. Cambridge, MA, Wright-Allen
Press: 213-256.
National Science Board (2009) "Building a Sustainable Energy Future: U.S. Actions for an Effective Energy
Economy Transformation. ."
OECD (2010). Uranium 2009: Resources, Production and Demand, OECD Publishing.
OECD and NEA (2010). Comparing Nuclear Accident Risks with Those from Other Energy Sources, Nuclear
Energy Agency, Organisation for Economic Co-Operation and Development. NEA No. 6861.
Richter, B. (2010). Beyond smoke and mirrors: Climate change and energy in the 21st century, Cambridge Univ
Pr.
USNRC (2010). Hidden Costs of Energy: Unpriced Consequences of Energy Production and Use, National
Academy of Science.
Vance, R. (2006). What can 40 Years of Red Books Tell Us? World Nuclear Association Annual Symposium.
Wald, M. L. (2008). "Can Nuclear Power Compete?" Scientific American Earth 3.0 18(5): 26-33.
http://proxy.library.vanderbilt.edu/login?url=http://search.ebscohost.com/login.aspx?direct=true&db
=buh&AN=36570719&site=ehost-live&scope=site.
Wallace, M. J. (2005) "Testimony before the U.S. Senate Committee on Energy and Natural Resources,
Hearing on the Department of Energy's Nuclear Power 2010 Program."
see Income_vs_Energy_use_over_time: drag the clock at the bottom back to 1965 and hit “Play”
http://www.eiolca.net/
iii http://www.sciencedaily.com/releases/2007/11/071114163448.htm
iv ibid.
v The Tennessean, 6/1/09.
vi http://pubs.usgs.gov/pp/p1625c/P1625C.pdf
vii http://en.wikipedia.org/wiki/Massey_Coal
viii See http://www.epa.gov/radtown/docs/coal-plant.pdf
ix http://www.epa.gov/hg/about.htm
x http://www.msnbc.msn.com/id/33448828/ns/us_news-environment/
xi http://en.wikipedia.org/wiki/Kingston_Fossil_Plant_coal_fly_ash_slurry_spill
xii http://www.systemdynamics.org/DL-IntroSysDyn/energy.htm
xiii http://www.youtube.com/watch?v=fjgdgAhOzXQ&feature=related
and http://www.youtube.com/watch?v=u0VjHg0juz4
xiv The Tennessean, June 11, 2009, “TVA plans mini nuke reactor for Tenn.” by Bill Theobald and Dave Flessner.
xv http://www.babcock.com/products/modular_nuclear/, retrieved 12/13/2010.
xvi http://www.nevadaappeal.com/article/20090306/NEWS/903069981/1070
xvii Release of 137Cs is of particular concern because its decay releases a hard gamma ray that can penetrate human
skin.
xviii Erik Talmadge and Mari Yamaguchi, AP, 3/17/2011
xix AP, "Pools for spent fuel could pose a danger,” 3/17/2011
xx Anne Paine, The Tennessean, 4/11/2011,
http://www.tennessean.com/article/20110411/NEWS11/104110335/Storage-used-nuclear-fuel-rods-TVA-plantselsewhere-stir-concern?odyssey=tab|topnews|text|FRONTPAGE
xxi Maybe this isn't a good argument. Most of the opposition to nuclear power is even more irrational than
Republicans support for it.
i
ii
U
U
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