Last week a three-judge panel of the U.S. Court of Appeals
in Washington ruled that the U.S. Environmental Protection Agency, EPA, had
“substantial record evidence” that greenhouse gases probably caused the climate
to warm over the past several decades, the EPA had concluded that greenhouse
gases are pollutants that endanger human health in 2009. Opponents to that determination had
essentially asked the Court to re-weigh the scientific evidence before EPA and
reach their own conclusion. However, the three judge panel wrote in the opinion
for the case that. “(t)his is not our role.”
Back in December 2009, the EPA officially found that greenhouse gases
in the atmosphere threaten the public health and welfare of current and future
generations the agency, and started on
the path to regulate carbon dioxide, CO2, after the "American Clean
Energy and Security Act”, also known as the Waxman-Markley energy bill was
defeated in the Senate. After collecting CO2 emission data from industry the
EPA “found” in 2012 that the largest carbon dioxide generators are the largest
stationary combustion sources. It was no surprise that the largest (coal)
electrical generation and industrial plants in the nation- big furnaces generate more CO2. For the past decade electrical generation has accounted for
approximately 40% of the carbon dioxide emissions in the United States and
worldwide. At the end of March 2012, the EPA proposed the first Clean Air Act standard for CO2 rule targeted at power plants. The agency plans to phase in industrial
facilities covered by the carbon rules through 2016. Under the new rule, new power plants will have to
emit no more than 1,000 tons of CO2 per megawatt-hour of energy produced. That
standard effectively changes the fuel of choice for all future power capacity
additions to natural gas, nuclear, or the renewable category (with government
subsidies). All existing plants and currently permitted and built in the next
12 months will be grandfathered and exempt from this new rule for now.
Coal electrical generation plants currently produce about
1,800 pounds of carbon dioxide per megawatt-hour of electricity. EPA says the CO2
rule that requires new plants to produce no more than 1,000 pounds of CO2 per
megawatt-hour as creating “a path forward for new technologies to be deployed
at future facilities that will allow companies to burn coal, while emitting
less carbon pollution.” The EPA in their new regulations and Department of
Energy, DOE, in their research grants are pushing forward on the development of
Carbon Capture. In June the International Energy Agency, IEA, released its preliminary 2011 estimates of world CO2 emissions from fossil fuel combustion.
World CO2 emissions rose by 1 billion metric tons, a 3.2 % increase over last
year to reach 31.6 billion metric tons. The
worldwide level of CO2 is now higher than the worst-case scenario outlined by
climate experts just five years ago and within 1 billion metric tons of the
IEA point of no return. (That is the point where mankind cannot hold global
warming at 2 degrees Celsius.)
In 2011 the top four
world generators of CO2 emission from fossil fuels were (from highest to
lowest) China, the United States, the European Union and India who edged out
Russia to take the number four slot. China increased emissions contributed
almost three quarters of the global increase, with its emissions rising by 720
million metric tons, or 9.3% to 8.46 billion metric tons of CO2, primarily due
to higher coal consumption. India’s emissions rose by 140 million metric tons
or 8.7% to 1.75 billion metric tons. Since 2000, China has more than tripled
its installed capacity of coal power plants, while India’s capacity has
increased by 50%. Neither country has used the most efficient designs and
technologies available for those plants and those plants will continue to
operate 24/7 for decades to come.
CO2 emissions in the United States, in contrast, fell by 92
million metric tons in 2011, or 1.7% to an estimated 5.32 billion metric
tons. The European Union increased their CO2 emissions from fossil fuel by
69 million metric tons to approximately 3.56 billion metric tons. Japan’s CO2
emissions increased by 28 million metric tons, or 2.4% to approximately 1.19
billion metric tons, as a result of a substantial increase in the use of fossil
fuels in power generation post-Fukushima tsunami. Russia and Canada reportedly remained
fairly stable from the previous year. Nonetheless, the IEA still believes that
it is still possible to prevent the earth’s temperature from rising more than 2
degrees Celsius if “timely and significant government policy action is taken,
and a range of clean energy technologies are developed and deployed
globally.” One of the key technologies according to the IEA is carbon
capture.
In 2009 DOE supported eleven projects to conduct site characterization
of geological formations for CO2 storage. Carbon capture is really three
activities: Gathering or capturing of CO2 from point sources (power plants,
industrial plants, and refineries), transporting the captured CO2 to a
geological storage site, and injecting the CO2 into the ground for permanent
storage and monitoring the site for eternity. Capturing and transporting CO2
from industrial plants is technologically possible but is currently prohibitively
expensive, though DOE’s National Energy Technology Laboratory and several
universities are exploring ways to bring down the costs or raise the costs of other
energy sources. A significant portion of
the CO2 generated in the United States and the world is not generated from large
stationary point sources, but from cars, homes, and smaller sites. Only about a
quarter of the CO2 generated from fossil fuel combustion annually is generated
at large point sources the only possible capture points. Storing even a portion
of this amount of CO2 would require capturing the gas at many locations around
the country and transporting it to facilities that could inject the CO2 into
appropriate subsurface rock formations. According to the researchers efficient
underground storage of CO2 requires that it be in the supercritical (liquid)
phase to minimize required storage volume.
In order for CO2 to remain in a supercritical phase, the pressure
in the storage reservoir must be greater than about 68 atmospheres and at temperatures
above 31.1°C. (Sminchak et al., 2001). These conditions require that the CO2 be
injected at high pressures, which can only be achieved at depths greater than
about 2,600 feet below the earth’s surface. The supercritical CO2 will be
injected into the geologic formations that are overlain by appropriate sealing
formations and geologic traps that will prevent the CO2 from escaping as the
CO2 injection well remains in continuous operation for years or decades. The
volumes of supercritical CO2 envisioned for carbon capture are huge. A recent U.S.
National Research Council report suggests that carbon capture and deep earth
sequestering could potentially induce earthquakes because significant volumes
of fluids are injected underground over long periods of time. However,
insufficient data exists at this time to evaluate this risk. An IPCC Special
Report on CO2 capture and storage suggests that between 73 and 183 million
metric tons of CO2 could be captured and stored worldwide from both coal and
natural gas energy plants each year (Metz, 2005). The IPCC envision that carbon capture and well
injection would take place at a number of locations, ideally places near to
power plants that produce CO2 to avoid long transportation distances under
pressure.
American Electric Power, AEP, participated in three DOE
funded projects to advance CCS technologies. All were conducted at the
Mountaineer Plant in New Haven, West Virginia (from which some of my power is
supplied within the PMJ Interconnection). AEP planned to replace its pilot demonstration
CO2 capture plant with a larger $668 million Carbon Capture and Storage
facility, which would have buried more than 1 million metric tons of CO₂ a year,
splitting construction costs evenly with the DOE, but failed to obtain the consumer
rate increases necessary to fund the experiment. The project has been
discontinued. In 2010 there were almost 1,400 coal fired electrical generating units in the United States if each were to be converted to carbon capture
operation the total cost would be almost a trillion dollars in construction
costs (assuming no cost over runs) and capture 1.4 billion metric tons of CO2
per year. This would represent 26% of the net annual CO2 emissions of the
United States and increase average electrical rates 25% nationally for just
building the units. Electrical rates would have to increase more if there were
any annual operating costs of the Carbon Capture unit. Actual rate increases
would be regional.
The AEP projects were demonstrations of Alstom’s Chilled Ammonia Process for Post-Combustion CO2 Capture. The process uses ammonium carbonate to
absorb CO2 and create ammonium bicarbonate. This resulting ammonium bicarbonate
is converted back to ammonium carbonate in a regenerator and is reused to
repeat the process. The flue gas, cleaned of CO2, but with the tell-tale smell
of the ammonia reaction, flows back to the stack and the captured CO2 is sent
for storage. Once captured, the CO2 is compressed into a liquid state and is
injected 1.5 miles beneath the earth’s surface. Several major pilot projects, in
Europe have also been cancelled in the last few years because of doubts over
their financial and technical viability. Some are still under consideration for
EU and government funding, but the need to rescue the Euro and European Banks
has taken the financial resources of the European Union. Ayrshire Power in
Scotland, blamed their cancelled plans for a new carbon-capture power station
at Hunterston on the recession and anxieties about winning funding from the
government and the same reasons were given for the cancellation of the
Longannet power station in Fife.
Globally, only a few,
small-scale commercial carbon capture projects are in operation. The oil and
gas fields in the North Sea are the site of the world’s first offshore
commercial CO2 capture and storage project. Carbon dioxide is captured at a
plant located on the offshore natural gas platforms and is stored underground
in a sandstone well approximately 2,600 feet below the sea bed. The CO2 tax
levied on offshore oil and gas operations by the Norwegian government made the
project worthwhile and the drilling rig and available aquifer made it possible.
CO2 is removed from the natural gas produced at the Sleipner field in the North
Sea and re-injected it into a very porous, permeable sandstone and saline
aquifer above the oil and gas reserves. Approximately 1 million metric tons of
CO2 have been stored each year since 2000 when the system went into operation. This
is just a small fraction of the 31.5 billion metric tons of CO2 released into
the atmosphere each year. It appears as
if the United States has passed the point of peak CO2, but the atmosphere of the
earth is interconnected and China and India appear to be increasing their CO2
emissions by 860 million metric tons a year. It matters what kind and how
efficient a power plant is installed in China or India since they will be
sending particulates and CO2 into the atmosphere for decades. Nonetheless, we
have no control over the growth in India and China’s coal fired power supply, nor
in the abandonment of nuclear power by Germany, Belgium, Switzerland and Japan in
the next decade in response to the damage to the nuclear reactors that occurred
in the Japanese Fukushima tsunami.
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