experts say that existing technology can reduce the carbon dioxide emissions
that may cause global warming, but it's very expensive, and the United
States isn't investing enough to make a difference.
President George W. Bush caught plenty of flak from environmentalists
when he refused to sign the Kyoto Protocol to reduce carbon dioxide
(CO2) emissions. Bush called the plan unworkable and unfair and claimed
it would devastate the U.S. economy without significantly cleaning up
the Earth's atmosphere. The president has acknowledged that CO2
may be contributing to global warming. But he promises there will be
solutions emanating from U.S. laboratories. "America is a leader
in technology and innovation," he says. "We all believe
technology offers great promise to significantly reduce emissions."
It's certainly true that engineers and scientists at universities
across the country are conducting research into technologies aimed at
capturing CO2 and rendering it harmless. The question is whether these
technologies can make good on Bush's claim. The answer appears
to be a qualified yes. "I think that without technology we will
not solve the problem, but technology alone will not solve the problem,"
says Howard Herzog, principal research engineer at MIT's Laboratory
of Energy and Environment. "The technologies exist, but do we
have the political will to pay for them?" Herzog says that currently
the necessary technologies are very expensive, while the market price
for CO2 shifts between $1 to $10 a ton. To make it more viable for companies
to invest in corrective technologies, that price needs to rise to around
$100 a ton. Ultimately, however, as with most technology, the cost of
these solutions should fall once they're in widespread use. Herzog
cites technology used by power plants to control sulphur emissions.
It, too, was initially costly, but as the industry became more efficient,
productivity gains more than offset the costs of the sulphur controls.
"The same thing could happen with carbon dioxide."
Across the country at the Renewable and Appropriate Energy
Lab at the University of California-Berkeley, program director Daniel
Kammen thinks fears about the cost of clean-up technologies are overstated
and agrees with Herzog that prices will tumble rapidly once they're
employed. Kammen says President Bush is right about the technologies,
but that his remarks ring hollow because the United States is not investing
in them. The energy sector invests less than 0.4 percent of revenues
into research and development, he says. That competes poorly against,
say, the pharmaceutical sector, where 15 percent of revenues are shoveled
into R&D. "The costs (of technologies) aren't too high.
What is expensive to do is not to invest."
There's not universal agreement that anthropogenic
CO2 contributes to global warming, but many researchers think the gas
acts like an atmospheric glass ceiling, trapping heat that is bringing
about huge changes in climate that may trigger droughts and floods.
Greenhouse gasses like CO2 result when fossil fuels, particularly oil
and coal, are burned, and about a fourth of these gasses vented into
the atmosphere come from the United States. Research sponsored by the
United Nations estimates that the world's climate has already
risen 0.6 degrees Celsius since the start of the Industrial Revolution
and predicts the Earth's climate could skyrocket another 1.4 to
5.8 degrees Celsius this century.
Ultimately, the best solution will be a reliance on alternative,
renewable energy sources that don't emit harmful pollutants, like
hydrogen, wind, and solar energy. But Herzog says the replacement of
fossil fuels with clean alternatives is 50 to 100 years away. And, given
that 85 percent of commercial energy is fossil-fuel based, an awful
lot of carbon dioxide could be spewed into the air during that period
unless something is done. That's why the immediate emphasis is
on so-called sequestration technologies that either remove CO2 from
the atmosphere or capture it before it's released. The culled
CO2 would then be safely stored away.
Herzog's group studies these technologies and assesses
their social and economic effects. Currently, he says, only two technologies
are economically viable. The first takes carbon dioxide and injects
it into the ground to make oil flow out more easily. The price of the
oil offsets the cost of the CO2. In the United States, oil companies
inject 32 million tons of carbon into the earth. The second is capturing
the CO2 that is a byproduct of the process used to cleanse natural gas.
Historically, the CO2 is released into the atmosphere, but it can be
captured and stored, perhaps underground, as well. It's a bit
more costly than venting the carbon, but the value of the natural gas
still makes it economically feasible. Where to store CO2 poses another
quandary. Two prime possibilities are pumping it underground or sinking
it into the oceans, but scientists still aren't sure that these
are safe options. So there is research underway to determine if they
are environmentally benign solutions.
Beverly Saylor, assistant professor of geology at Case
Western Reserve, is working with the Ohio Coal Research Consortium to
study the engineering and science of geological sequestration. She analyzes
the reaction rates of carbon dioxide with minerals it may come in contact
with underground. Saylor also simulates deep Earth conditions in her
lab to study how CO2 behaves 800 meters below the Earth's crust.
"We could start earthquakes and cause a different kind of carbon
dioxide problem," she notes. Scientists are convinced that CO2
will remain safely stored in old oil and gas reservoirs, but they don't
know for how long. That's a key question. Saylor estimates it
could work for 1,000 to 10,000 years. That's encouraging, but
it's still far from being a precise estimate.
Ocean sequestration also offers some hope. It's
theorized that CO2 dumped into the ocean, two miles below the surface,
will sink to the bottom and stay there for a very long time. Again,
the question is for how long. Also unknown is how carbon dioxide will
react under such great pressure and whether it will harm deep-sea organisms.
The Moss Landing Laboratory at California State University is investigating
another means of using the seven seas to rid the world of unwanted CO2:
ocean fertilization. Here's how it could work: Small plant matter,
phytoplankton, consume CO2 and are in turn eaten by zooplankton (small
animals), which are then gobbled up by bigger fish, and the process
continues on up the food chain. The carbon, now part of dead organisms
or fecal material, sinks to the ocean floor and is remineralized to
CO2 by bacteria through the decomposition process. Scientists at Moss
are considering the effects of supercharging the cycle by adding fertilizers
to promote phytoplankton growth so that even more CO2 can be absorbed.
They are seeding small amounts of iron sulpha—tea
fertilizer—into an area of ocean 800 miles south of New Zealand
and watching to see how it affects the carbon cycle. The results are
then compared with ice cores from the last glacial period when atmospheric
CO2 was low. "Our research could form the foundation for figuring
how much carbon could be put into the ocean," explains Kenneth
Cole, Moss director. The fertilization process is controversial, but
it gets attention because it's an inexpensive way to sequester
huge quantities of carbon. Cole doesn't dispute it may cause other
environmental problems, "but if we start having serious warming
problems we may be forced to consider this."
At the Goldwater Materials Science Laboratories at Arizona
State University, researchers are studying techniques to turn gaseous
CO2 into an environmentally-friendly rock. The resulting carbonate could
be used to refill mine pits in land reclamation efforts. The idea is
to take carbon dioxide from the atmosphere and mix it with certain minerals,
like olivine or serpentine. "We are studying the atomic level
and trying to understand what governs the reaction rates of carbon dioxide
and rocks," says Michael McKelvy, director. But MIT's Herzog
is pessimistic, saying the economics of turning carbon to rock appear
"intractable." We can accelerate what takes nature 100,000
to a million years to do, Herzog admits, "but the cost may be
Dirt is another possible option for storing CO2. Agricultural
schools are looking at changes in farming practices to sequester carbon
dioxide terrestrially. The U.S. Environmental Protection Agency estimates
that of the 1,500 metric tons of carbon the United States puts into
the atmosphere each year, 30 million come from agricultural practices.
Undoubtedly, the manufacturing of herbicides and fertilizers generates
pollution, but just plowing the fields creates masses of CO2. Planting
fields without plowing can cut CO2 emissions significantly, and reforestation
programs can help suck carbon from the atmosphere and siphon it into
the soil. Keith Paustian, professor of soil ecology at Colorado State
University, uses computers and soil analysis to study the impact of
land management practices on carbon emissions. He argues that improvements
in agricultural methods can have the most immediate effect in reducing
emissions. "We don't have a lot of hydrogen cars running
right now, but changes in agricultural practices can have an effect
in the next three to five years," Paustian claims.
Of course, before carbon dioxide can be stored, it first
must be captured and isolated. One futuristic idea comes from Klaus
Lackner, a physicist at Columbia University. He suggests erecting giant
adhesive strips down wind from cities and factories. They would be treated
with a chemical that reacts with CO2, so as carbon dioxide drifts past,
it sticks to the strips and is removed from the air. Separating CO2
from the waste stream of a power plant or factory constitutes about
75 percent of the cost of sequestration, researchers say. It's
costly because it requires either building new plants with carbon-emission-reduction
technologies or refitting existing ones. So engineers are looking into
chemical and physical absorption methods, as well as new membranes to
filter out CO2. Universities also give researchers opportunities to
seek multidisciplinary approaches to the problem. Berkeley's Kammen,
for instance, employs teams of engineering and
public-policy graduate students to investigate potential solutions.
"Sometimes it's just small policy changes that can help
make it easier to adopt certain technologies," he says. For example,
in Kenya, kerosene fuels most households. Not only is kerosene incredibly
polluting, it's costly and the price is unstable.
While Kenyans were interested in solar energy, they didn't
know much about it. So one of Kammen's teams organized a conference
in east Africa, bringing together consumers, manufacturers, and budding
entrepreneurs. One student who attended now writes a column for east
Africans who want to learn how to sell solar panels and windmills. Back
at MIT, Stephen Connors is coordinator for multi-disciplinary research
at the Laboratory for Energy and the Environment. Connors—whose
teams can include such disciplines as engineering, architecture, and
computer science—argues that breaking down the walls between academic
departments should help speed the development of technologies. "The
interesting and challenging topics are at the interfaces between disciplines,
particularly if they have a societal dimension," he says.
Clearly the effort to remove carbon dioxide from the
atmosphere will require a variety of solutions. A paper published in
Science last year, in which 18 engineers and scientists analyzed existing
technologies for carbon reduction, concluded, "It is unlikely
that a single silver bullet will solve this problem." But for
any of those technologies to become fully effective it requires strong
political will. MIT's Herzog says what is needed is a federal
program that's as intense, focused, and as well funded as the
1960s moon-landing program. If it becomes clear that this is one of
the government's top priorities, the necessary R&D, innovation,
and investment will follow, he says. But that remains a big "if."
The Bush White House has backed off from its original stance, calling
the link between global warming and greenhouse gasses "bad science."
It now says the scientific evidence "justifies a serious and measured
response." The technological silver bullets in which President
Bush has placed his faith do exist. It remains an open question, however,
whether the United States is ready to bite down on them.
Lisa Busch is a freelance writer living in Alaska.
She can be reached at firstname.lastname@example.org.