Carbon dioxide and other greenhouse gases (GHGs) are responsible for global warming, the long-term worldwide average warming experienced since the industrial revolution. GHGs arise from human use of fossil fuels for energy. Major emitters of GHGs include both industrialized countries and, in recent decades, developing countries as well. Higher global temperatures cause the extremes of hot and cold, and wet and dry, weather of recent years. This blog examines global warming and its effects.
See the Tabbed Pages for links to video tutorials, and a linked list of post titles grouped by topic.
This blog is expressly directed to readers who do not have strong training or backgrounds in science, with the intent of helping them grasp the underpinnings of this important issue. I'm going to present an ongoing series of posts that will develop various aspects of the science of global warming, its causes and possible methods for minimizing its advance and overcoming at least partially its detrimental effects.
Each post will begin with a capsule summary. It will then proceed with captioned sections to amplify and justify the statements and conclusions of the summary. I'll present images and tables where helpful to develop a point, since "a picture is worth a thousand words".
Thursday, September 19, 2013
The Keystone XL Pipeline Would Significantly Worsen Global Warming
Summary.President Obama is weighing a decision
whether it is in the national interest to approve the Keystone XL
pipeline.It would carry bitumen from Alberta’s tar sands to refineries on
the U. S. gulf coast.He
has said he would not approve the pipeline if it would make climate change
sands oil, being very different from conventional petroleum, requires far more
energy, derived by burning fossil fuels, to extract it for shipment and to
refine it for final use.The high
capacity of the pipeline would transport so much bitumen that, once burned as
refined fuel, it would add between 82.5 million tons and 181 million metric
tons per year of carbon dioxide to the atmosphere, corresponding to at least
1.4% of all emissions from the U. S. The pipeline would commit the U. S. to these emissions for each
year of its operational lifetime, perhaps 40 years or more.
of the Canadian government have visited Washington several times in recent months
advocating assertively for approval of the pipeline.Clearly the Keystone XL pipeline figures
importantly in Canadian political and economic considerations.Those interests do not necessarily overlap
with those of the United States.
energy economy may be considered as a zero sum undertaking, balancing new
investments in fossil fuels with those in renewable energy.It is estimated here that if the investment
in the Keystone XL pipeline were instead directed toward investment in wind
energy, it could result in installation of 1,420 high capacity wind turbines
and construction of a high voltage transmission line 1,563 miles long.This investment would provide many jobs
during construction, making a positive contribution to economic activity in the
President should not approve the XL pipeline.Instead, his administration should promote development of renewable
energy sources as avidly as possible.
extent of warming of the earth’s climate depends not on humanity’s annual rates
of adding new greenhouse gases to the atmosphere, but rather on the total
accumulated amount of such gases added since the industrial revolution
began 150 years ago.Carbon dioxide, the
main greenhouse gas, remains in the atmosphere for a century or even longer
(referring to the large portion not captured by photosynthesis or absorbed into
the oceans).Therefore, even if we
reduce our annual emissions rate we can never lower the accumulated
total, but rather only minimize the new higher accumulated total of
greenhouse gases in the atmosphere.For
this reason it is imperative to migrate away from a fossil fuel-driven energy
economy as soon as possible, and shift toward a renewable energy economy.
the Keystone XL pipeline would commit the U. S. to additional accumulation of
new greenhouse gases from burning this fuel throughout its operational
lifetime, to the extent of at least 1.4% per year of all fossil fuel derived
carbon dioxide emitted by the U. S.Thus
use of Canadian bitumen for the lifetime of the pipeline would add
significantly to the world’s burden of new greenhouse gases.Additionally, extracting and refining tar
sands bitumen requires large amounts of energy, which itself is derived by
burning fossil fuels and creating more greenhouse gas emissions.Accordingly, the pipeline would significantly
and adversely affect global warming if it were approved.The urgings of Canadian government officials
should be rejected.It is not in the
interests of the U. S. to grant approval.
the U. S. should take every opportunity
to develop renewable sources of energy that have very low or zero rates of
emission of new greenhouse gases.Government and corporate policies should be encouraged that promote
migration away from fossil fuel use and toward a renewable energy economy.
Keystone XL pipeline (XL) is an international transport pipeline project
intended to carry bitumen (Alberta tar sands oil) from the Canadian border to refineries on the
U. S. Gulf Coast.Since the project has
an international aspect, involving oil transport across the Canada-U. S.
border, it requires positive review by the U. S. Department of State and
approval by the President.The query to
be resolved is whether this is in the national interest.
While the XL
pipeline application has been pending, President Obama delivered a major speech
on his energy policy
on June 25, 2013.He said he would not approve the application
if the pipeline would make climate change “significantly” worse.
aggressively promoting approval of the pipeline in numerous visits to
Washington.Alison Redford, the Provincial Premier of
Alberta, visited Washington, D.C. for the fourth time in 18 months during the
week of April 8, 2013 to press the case for favorable action on the XL pipeline.
9, 2013Canadian Minister of Natural Resources Joe Oliver met with U. S. Secretary of Energy
Ernest Moniz.Minister Oliver has visited Washington on numerous occasions to promote approval
of the pipeline application.In
addition, Canadian Prime Minister Stephen Harper is reported to have sent a
letter to President Obama
in August 2013 in which Mr. Harper proposed "joint action to reduce
greenhouse gas emissions in the oil and gas sector."By this gesture he seeks to further approval
of the pipeline application.This offer
is a concession to U. S. concerns about greenhouse gases that Canada has not previously made.
The New York Times reported on August 25, 2013 that Canada would find other modes of transporting the
bitumen to the U. S. market and/or other destinations for the
bitumen if the XL pipeline application is rejected. Nevertheless, internal Canadian government documents
released to the Canadian Pembina Institute reveal that Canada has been relying on approval to expand
production of bitumen from the tar sands.
22, 2013]An editorial contributor to the New York
Times reportsthat the Canadian government is
restraining government scientists from free and open communication of their
findings, especially in the fields of climate change, the Alberta tar sands,
and fisheries.The writer concludes “the
Harper [Canada’s prime minister] policy seems designed to
make sure that the tar sands project proceeds quietly, with no surprises, no
bad news, no alarms from government scientists.”
It is clear that
approval of the Keystone XL pipeline is a major issue in Canada, both politically and economically.
of bitumen.Bitumen occurs as a highly viscous fluid or a
soft solid, mixed with sand.Extracting tar sands bitumen
deposited near the surface requires expending about 20% of the energy content
of the bitumen.Deeper reservoirs
require about 30% of the energy contained in it. Obtaining conventional oil, on the other hand,
needs only about 4%. Bringing the bitumen to the surface and freeing it from
the sand mixture requires heating the raw material to temperatures hot enough
that the bitumen flows more freely.The
process produces waste water that now includes toxic heavy metals and bitumen
components that have to be stored to keep the waste from contaminating running
Refining tar sands bitumen takes extra processing
compared to refining conventional petroleum.The additional steps require additional large amounts of energy and use
large amounts of water.
extracting and refining tar sands bitumen is far more energy intensive than
recovering and refining conventional petroleum.
The Keystone XL
pipeline is expected to
transport 830,000 barrels of fuel a day.Refining petroleum yields about 75% of
carbon-containing fractions that are suitable for use as fuels.Although bitumen is different than petroleum,
If bitumen provides the same yield, this writer estimates conservatively that the annual
amount of fuel transported would emit 82.5 million tons of carbon dioxide (CO2)
a year when burned. (This figure does
not include the extra emissions arising from the energy used in extraction
and refining.) This works out to this pipeline alone transporting fuel that
would emit 1.4% of all CO2 produced by burning fossil fuels in the U. S. (fossil fuel data).
Another report estimates annual emissions to be 181 million
metric tons per year, or more than twice as much as the lower estimate.These emissions would continue for the useful
service lifetime of the pipeline, perhaps 40 years or more.Not approving the pipeline and not extracting
this amount of bitumen would prevent this amount of emissions indefinitely into
fossil fuel use, such as by building the XL pipeline, is but one arm of the
energy economy’s zero sum undertaking.In weighing whether
to approve the Keystone XL pipeline, the choice is not whether to approve it or
simply to reject it. Rather the correct
decision to consider is whether to use the funds foreseen for the Keystone XL investment,
prolonging the fossil fuel energy economy, or to shift such investment to expand
renewable energy.A current estimate of the cost of constructing the XL portion of the Keystone system is US$7 billion.Earlier phases of the Keystone system
experienced cost overruns of as much as 100%; if so, the XL portion under
consideration could cost as much as US$14 billion.
noted above, the pipeline, if built, commits us to continued atmospheric
emissions of CO2 over its full service lifetime, perhaps 40 years or
more.If the pipeline were not built and
its intended capacity for bitumen remained in the ground, emissions equal to
about 1.4%/yr of the U. S. total would be avoided.The longer we delay the abatement of
emissions, the more intensive and more expensive mitigation efforts would need
energy is a second arm in a zero sum energy economy.An alternative strategy is to shift the US$7-14
billion investment envisioned for the pipeline into developing industrial
scale, renewable energy sources and energy transmission infrastructure. We
should stop harvesting tar sands oil and build wind farms and solar farms
instead.We should reject new oil
pipelines in favor of new transmission lines to deliver electricity from those
farms to energy consumers.
cost of wind energy generation is falling dramatically each year.A report from the Lawrence Berkeley National
a facility of the U. S. Department of Energy, reports that the levelized cost of
electricity from wind (a measure of the expense incorporating all costs throughout the lifetime of a project) ranges
from US$20 to US$40 per MWh (megawatt-hour, a unit measuring the amount of
energy).It is lowest in the windy
portion of the U. S., the Midwest interior. Broadly, this is the
region that the projected Keystone XL pipeline would traverse.
costs for wind energy based on generation capacity are as low as about
US$1,760/kW (kilowatt, a unit of power, or the rate of generating energy in a
fixed time).The average capacity of
installed individual turbines was almost 2 MW in 2012.Wind power provides an important source of
jobs in the U. S. economy, since the domestic
content of turbines increased from 25% in 2006-2007 to 72% in 2012.
need new high voltage transmission lines to carry power from a renewable
facility to consumers.The American Electric
Power Company estimates costs
for constructing a lower-voltage line (345 kV) at about US$1.1-2.0 million
(2008 dollars) per mile, and for the highest voltage listed (765 kV), a cost of
US$2.6-4.0 million per mile.Most of
this expense comes from direct labor costs (construction, 41%; siting and
management, 8%) and in labor involved in providing the materials (the materials
cost is given as 41% of the total).Thus
it is seen that constructing a high voltage transmission line provides a large
number of high-skilled jobs during the project.
investment in wind energy for the Keystone XL pipeline provides a high amount
of installed capacity.This writer has estimated
investing in wind energy for a cost, US$10 billion, intermediate between the
stated cost of the XL pipeline, US$7 billion, and a 100% cost overrun.The sum is divided evenly between wind
turbines and a transmission line.Using
the information above it is calculated that
investing in 2MW turbines would provide 1,420 turbines; and
investing in a 765 kV transmission line would provide 1,563 miles.
with even larger power capacities
are currently becoming available.Turbines
that can operate at low wind speeds with high efficiency are available.Wind turbines have to be installed with wide
separations, so that original use is retained for a large fraction of the land
that the wind farm occupies.
concluded that investing in the Keystone XL pipeline is not in the national
interest of the U. S., as it contributes
significantly to worsening the problem of global warming.Investment should be directed instead to
renewable energy sources, such as industrial wind farms described here, solar
farms and the like.