- HONOLULU - At the Natural Energy Laboratory of Hawaii on the sun-splashed
Kona Coast, a pipe drops steeply from coastal lava fields through azure
waters to depths of 1,000 feet. At some point during the next year, scientists
will send liquid carbon dioxide coursing through the pipe and into the
Pacific Ocean.
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- The goal: to find out whether it's safe
to use the earth's oceans as storage bins for massive amounts of carbon
dioxide (CO2) - a greenhouse gas linked to global climate change.
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- For environmentalists, the experiments
represent a red herring that could encourage even greater greenhouse-gas
emissions and divert resources from more valuable climate-change efforts.
But for some scientists, the international project represents an elegant
solution to the worsening problem of CO2 emissions and fossil-fuel dependence.
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- "It will allow us to use fossil
fuels without carbon emissions," says Howard Herzog, a research engineer
at Massachusetts Institute of Technology in Cambridge.
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- Carbon levels in the earth's atmosphere
have gone up about 25 percent since the Industrial Revolution, largely
because of the combustion of coal, oil, and natural gas that supply about
85 percent of the world's energy needs. And that level is increasing.
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- "It's not only the higher levels
that we are worried about," says Gerard Nihous, an ocean engineer
with the Pacific International Center for High Technology Research. "It's
the rate of change. Rapid changes in the atmospheric chemistry might create
rapid changes in climate."
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- Meanwhile, fossil-fuel consumption -
spurred by low oil prices and industrialization in the developing world
- continues to skyrocket. The use of renewable energy, such as wind and
solar power, is lagging considerably. And nuclear energy, which produces
almost no greenhouse gases, is a public pariah. In addition, the cutting
down of forests that soak up greenhouse gases is outstripping reforestation.
Furthermore, scientists say even the expected advances in all of these
energy methods will not be enough to stabilize, let alone reduce, CO2 emissions.
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- How to reduce emissions
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- All these reasons make the industrialized
nations' target for emissions reduction look even more daunting. By 2012,
they want a 5 percent to 8 percent reduction in greenhouse-gas emissions
from 1990 levels.
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- As an alternative and complementary solution,
scientists are proposing injecting CO2 into the ocean. The gas, to be captured
from flue gases and other power producers, will be injected at depths of
1,000 feet or more via pipes that may be based on land or dragged under
specially outfitted oil tankers.
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- By putting the CO2 under high pressure,
the gas will remain in liquid form and stay in the ocean for several centuries
before bubbling to the surface. This, scientists claim, will give humans
the breathing room to continue to use fossil fuels until more efficient
technologies are developed, emissions are reduced, or fossil fuels become
scarce and expensive. The benefits to this proposal are clear. Technology
to capture CO2 with special solvents and convert it into a liquid already
exists. And to capture the CO2, power plants would only need to retrofit
their facilities with new equipment, they wouldn't have to construct a
whole new power- supply system.
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- These two factors mean that CO2 capture
would most likely be considerably cheaper than other solutions.
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- It's happening anyway
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- Most important, say project scientists,
is the fact that the oceans are already the planet's largest reservoir
of carbon gas. They absorb between 50 percent and 80 percent of the carbon
produced by humans. "There's a huge exchange between the atmosphere
and the ocean," says Stephen Masutani, a University of Hawaii engineer
working on the Kona project. "The bottom line is, it's happening anyway."
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- But CO2 storage in deep oceans is no
slam-dunk. Capturing the CO2 from power plants and other carbon emitters
will initially increase the cost of power by 50 percent to 100 percent,
something that will meet resistance from utilities, car manufacturers,
and consumers.
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- How to distribute the cost equitably
among countries is also problematic. Also, funding for CO2 capture - although
dramatically increased over previous years - is minuscule when compared
with government and private funding for clean-burning technologies and
strategies for greenhouse-gas mitigation.
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- Down with 'ocean dumping' Many environmentalists
vow to oppose the CO2 storage, which they have dubbed "carbon dumping."
They say efforts to capture carbon, let alone put it in the deep ocean,
are misplaced. They fear that higher CO2 levels will harm marine life due
to increased acidity, something the scientists hope to study during the
experiments.
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- Critics also note that the oceans are
warming, and they question whether this will result in the CO2 bubbling
up quickly, escaping into the atmosphere.
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- Besides, environmentalists say that figuring
out a way to allow mankind to maintain and even increase current levels
of fossil-fuel consumption is a misguided goal in the first place.
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- "The whole purpose of this exercise
is to stabilize atmospheric gases at a level that will avoid dangerous
climate change," says Gary Cook of Greenpeace USA. "People are
not considering what the implications of increasing fossil-fuel-burning
activities have on that objective. I don't know any environmental group
who is in favor of ocean dumping."
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- http://www.csmonitor.com/durable/1999/04/27/fp2s1-csm.shtml
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