Can anyone explain to me why the use of olivine, to adjust ocean pH
and thus increase natures CDR, should not be used? It does seem
somewhat dirt simple.
Also, here is an eye opener concerning the importance of maintaining
balance in the marine environment:
Otters and Climate Change
<http://www.loe.org/shows/segments.html?programID=12-P13-00037&segmentID=4>
According to two scientists at the University of California at Santa
Cruz, a small animal could have a big impact on climate change.
Professor Chris Wilmers explains how sea otters could be key to
preserving kelp forests, one of the world’s great carbon sinks.
Best,
Michael
On Friday, August 23, 2013 11:05:20 AM UTC-7, Greg Rau wrote:
Article below. The usual suspects and viewpoints, e.g. :
"Pulling vexing carbon emissions straight from the sky might
become an important way to keep climate change in check. As pilot
projects move forward, the prospect of capturing carbon dioxide
from the air is growing increasingly plausible, though it may be
some time before the technology, the demand and the costs align to
make a dent in global emissions."
To review, pulling those pesky carbon emissions straight from the
sky already annually consumes 55% of our emissions for free, and
the absolute quantity of this "DAC" is (lucky for us) increasing:
http://www.sciencemag.org/content/early/2013/08/07/science.1239207.full
<http://www.sciencemag.org/content/early/2013/08/07/science.1239207.full>
If one is interested in further "denting" global emissions,
perhaps the first thing to do is to figure out how to additionally
accelerate/enhance/modify/engineer these existing, highly
successful systems, rather than ignoring nature and designing a
new air capture process from the ground up.
"....for carbon capture systems [DAC], the main energy sink isn't
so much in collecting CO2 in the first place, but in regenerating
the absorber and making a pure stream of the gas."
Exactly. This is why nature's existing, very successful CRD
assiduously avoids this step and why our attempts at further
"denting" air CO2 should also. On the other hand if CO2 EOR is
your end game, then you are obviously stuck with making conc CO2
while also increasing atmospheric CO2: typically in EOR CO2 in<<
oil CO2 out. How such schemes get mentioned in the context of
saving the planet is something I find breathtaking.
Speaking of actually saving the planet, if you haven't already
done so, there's still time to vote for The Planet Physician's air
capture (and so much more) concept here:
http://climatecolab.org/web/guest/plans/-/plans/contestId/20/planId/1303630
<http://climatecolab.org/web/guest/plans/-/plans/contestId/20/planId/1303630>
and/or vote for this point source CO2 mitigation idea:
http://climatecolab.org/web/guest/plans/-/plans/contestId/10/planId/1304003
<http://climatecolab.org/web/guest/plans/-/plans/contestId/10/planId/1304003>
Your humble messenger,
Greg
CARBON CAPTURE:
Air capture needed as a tool to fight climate change, scientists say
Umair Irfan, E&E reporter
Published: Friday, August 23, 2013
Pulling vexing carbon emissions straight from the sky might become
an important way to keep climate change in check. As pilot
projects move forward, the prospect of capturing carbon dioxide
from the air is growing increasingly plausible, though it may be
some time before the technology, the demand and the costs align to
make a dent in global emissions.
Earlier this year, instruments showed atmospheric carbon dioxide
concentrations rising above 400 parts per million for the first
time in 800,000 years (/ClimateWire/
<http://www.eenews.net/climatewire/stories/1059979974/>, April 24).
Energy consumption, and consequently carbon emissions, is poised
to grow further even as cars, homes and aircraft become more
efficient. Fossil fuels will continue to be the major energy
source in the coming century as countries like China harness this
energy to drive economic development.
As a result, some researchers argue that direct air capture is a
necessary, though not sufficient, component of any climate change
mitigation strategy.
"Our view is that air capture is a pathway that could be quite
important," said David Keith, president of Carbon Engineering, a
firm developing industrial air capture systems. He explained that
controlling emissions at the source makes sense for large
facilities like power plants and factories but scrubbing carbon
dioxide from tailpipes or jet exhaust is too expensive.
The transportation sector accounts for 28 percent of greenhouse
gas emissions in the United States, according to U.S. EPA, so
there is still a critical need for a way to reduce the overall
carbon dioxide produced from mobile sources.
Trapping CO2 in a liquid
Carbon Engineering is addressing this with a box fan-like air
contactor that uses a liquid to sop up carbon dioxide from the
air. The liquid, now enriched, circulates to a regeneration
facility where it releases the carbon in a pure stream under high
temperature.
This pure carbon stream is very useful, Keith observed. Carbon
dioxide is a raw material for certain industrial processes,
drillers use it to squeeze out more oil and gas from depleted
wells and it serves as a building block for liquid fuels.
"We are trying to reduce the risk by using technologies that are
proven," he said. The company is designing a large pilot plant
that will capture 1 kiloton of carbon dioxide annually, due to
come online next year in Alberta.
Putting carbon dioxide to work is an important step toward making
direct capture economically feasible as well as environmentally
sustainable. Unlike a stream from a carbon capture system attached
to a coal-fired generator, an air capture system recirculates
carbon that is already in the atmosphere.
Using this carbon instead of the stuff from the ground to make
gasoline or jet fuel means it offsets humanity's carbon output so
that there is no net change in CO2 concentrations in the
atmosphere, provided the energy driving the process comes from a
carbon-neutral generator.
"When you drive your car and emit some carbon and I capture that
carbon and use it to make fuel for the car, then effectively I've
created a closed loop," said Tim Fox, head of the Energy and
Environment Division at the Institution of Mechanical Engineers
speaking last month at the U.S. Energy Association in Washington, D.C.
Because carbon dioxide is fungible once it enters the atmosphere,
Fox said it doesn't matter where developers build an air capture
system. It doesn't have to be near a specific carbon source and
can use cheap, marginal land, thereby reducing overhead.
Fox suggested that engineers could site air capture systems near
stranded renewable energy sources, like sunny islands or windy,
desolate cliffs.
Would zero-emission vehicles cost less?
However, others are skeptical. "Capture from the air is very
expensive. Those ideas just make it more expensive," said Howard
Herzog, senior research engineer at the Massachusetts Institute of
Technology's Energy Initiative.
Herzog co-authored a study in 2011 that concluded direct air
capture uses too much energy and costs too much to be an effective
strategy to fight climate change (/ClimateWire/
<http://www.eenews.net/climatewire/stories/1059957553/>, Dec. 13,
2011). He said gradually switching to zero-emission vehicles would
likely be cheaper and more effective at reducing emissions than
offsetting tailpipe CO2 with air capture.
In order for air capture to make a difference in the climate, the
technology and economics would have to change radically. "The
first thing that's essential is you have to totally decarbonize
your power system," Herzog said, referring to the energy needed to
feed direct air capture devices. "The second thing, the
electricity, the power you buy from this system, must become
inexpensive. If that's the case, then it starts becoming more in
the realm of possibility."
Still, researchers are pressing on and looking for better ways to
collect carbon dioxide from the air. "I think people are too
pessimistic," said Klaus Lackner, director of the Lenfest Center
for Sustainable Energy at Columbia University. "If you look at the
first-of-a-kind price of a new technology, it's not terribly
informative."
Air capture systems would follow cost trajectories similar to
those of wind and solar energy as the devices get better and
companies build more of them, Lackner said. He noted that for
carbon capture systems, the main energy sink isn't so much in
collecting CO2 in the first place, but in regenerating the
absorber and making a pure stream of the gas.
'Cleaning up' after ourselves
Scientists are therefore concentrating on improving the mechanisms
used to snag and release carbon dioxide. Lackner developed a
mechanism that passively collects CO2 on a membrane and releases
it when wet, thereby avoiding energy-intensive fans and high
temperatures. Kilimanjaro Energy is currently working to
commercialize this system.
The process, however, still requires more energy than capturing
emissions at the source. "The bottom line is, I pay a penalty, but
it's a relatively small penalty, and that penalty is worth it for
going after those emissions no one else is," he said.
In addition, air capture creates leverage that could aid
international climate negotiations. "You could tell, for example,
the coal producers or the coal consumers, 'You should clean up
your own CO2, but if you don't, we will do it on your behalf and
we will charge you for it,'" he said.
One criticism is that directly trying to change the atmosphere
falls within the shadow of geoengineering, so air capture deserves
extra scrutiny. Another issue is that some environmental groups,
like Greenpeace, view carbon capture systems as a moral hazard and
a way to enable complacency. With a way to pull carbon out of the
air, people will not limit their emissions and will do less to
address climate change, the argument goes.
Lackner said the motivation here is actually the opposite: Because
the warming planet is such a threat and current systems aren't
doing enough to solve the problem, researchers need to pursue
every option and don't have the luxury of leaving direct air
capture off the table.
"It's cleaning up after yourself, and it has very little to do
with geoengineering," he said. "I view this as CO2 emissions
control and closing the anthropogenic carbon cycle."
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