- Statoil, Norway’s state
owned oil company, is doing two remarkable things about Sleipner T, a gas
rig in the middle of North Sea. One is the integration of social democracy
and oil wealth. Technicians are paid around NKr600,000 ($100,000) a year,
private rooms with television and ensuite bathrooms, and work two weeks
out of every six. Second, the interaction of an innovative company and carbon
tax, has resulted in limiting the contribution of CO2 to global warming.
Instead of being pumped into the atmosphere, it is reinjected into the
ground, 1,000 meters below the seabed. - CCS, as explained in the
second initiative above, is widely seen as the possible quick fix for
global warming. Currently, coal produces 50% of America’s electricity, 70%
of India’s and 80% of China’s. Its attraction at a time of concern about
energy security is enhanced owing to the possibility of wide distribution
around the globe. Burning coal is the cheapest way of generating
electricity. Coal produces around 40% of the CO2 emissions from energy
use. - Coal has enjoyed a revival
in recent years due to high gas prices. In America some 150 new coal-fired
power stations are on the drawing board. In China, two 500 MW coal-fired
power plants are starting up every week, and each year the country’s coal-fired
power-generating capacity increases by the equivalent of the entire
British grid. - Standard pulverized-coal
(PC) generation can be made a bit cleaner by burning the fuel at higher
temperatures. “Ultrasupercritical” generation can cut CO2 emissions by a
fifth, however, it is not enough if demand goes on increasing. CCS thus
offers an attractive option. - CCS is being done in three
places – at Sleipner; at In Salah in Algeria, where the CO2 removed from
gas produced by a joint venture between BP, Statoil and Sonatrach,
Algeria’s state-owned energy company, is stored in the desert; and at the
Weyburn oil field in Saskatchewan, Canada, where the CO2 produced by a
coal gasification plant in North Dakota is piped across the border and
used to increase the pressure in a partly depleted oil field. This
process, known as enhanced oil recovery (EOR), is in use in 70 oil fields,
around the world, but at Weyburn, unusually, some of the CO2 remains
underground. - CCS is done in four
stages. First, CO2 is separated from other gases. Second, CO2 is moved
along in pipelines. Third, CO2 is injected into the ground. Fourth, CO2 is
stored underground, probably in depleted oil and gas fields or in porous
briny rock. - The constraint is in terms
of the cost of deploying technologies that cover the four stages at a
reasonable cost and at a scale that make some impact on the emissions. It
is estimated that if 60% of the 1.5 billion tons of CO2 that America
produces every year from coal-fired power stations were liquefied for
storage, it would take up the same amount of space as all the oil the
country consumes. - Integrated gasification
combined-cycle (IGCC) plants have been built to foster CSS, where cost is
turned into gas before using it to generate electricity. The resulting CO2
and hydrogen are then separated, the hydrogen used to generate electricity
and the CO2 stored. - GE has bought Chevron’s
IGCC technology. According to GE’s Steve Bolze, cost of generating
electricity from IGCC technology is 20-25% higher than a pulverized coal
plant. It is expected that once the cost of separating carbon in taken
into account, IGCC may be cheaper. Philips Joubert, president of power
systems at Alstom, however, believes that IGCC is not cheaper, even with
CCS. A study by MIT published in March finds that generating electricity
from an IGCC plant with carbon capture is 35% more expensive than
pulverized coal without CCS; but pulverized coal plant with CCS is 60%
more expensive than pulverized coal plant without.
Source: The Economist, June 2nd 2007. (“Dirty King Coal”
pp. 22-24)