Carbon capture analyst: 'Coal should stay in the ground'

December 2, 2015

Serious flaws have been found in a decade's worth of studies about the best way to reduce greenhouse gas emissions and stabilize the climate.

The findings, from the University of Michigan, are released as world leaders at COP21 attempt to negotiate the globe's first internationally binding climate agreement.

The U-M researchers have found that most economic analysis of carbon capture and storage, or CCS, technology for -fired power plants severely underestimates the technique's costs and overestimates its efficiency. CCS involves sucking carbon out of coal-fired power plants' flue gases, compressing it and then injecting it deep underground.

The new analysis puts the cost of reducing with CCS-equipped coal plants higher than any previous study—and most importantly, higher than wind and comparable to solar power. It's the first study to confront the so-called 'energy loop' inherent in the CCS process.

Beyond a one-time 'energy penalty' these plants pay because they have to burn more coal to power devices that capture carbon, the researchers say the disadvantage compounds until fuel costs leap to four times today's accepted estimates.

"The conclusion is that renewables will be a cheaper alternative to reducing carbon emissions from coal, at least in the United States and likely globally," said Steve Skerlos, U-M professor of mechanical engineering, and civil and environmental engineering.

"To us, this means policymakers need to stop wasting time hoping for technological silver bullets to sustain the status quo in the electric sector and quickly accelerate the transition from coal to renewables, or possibly, natural with CCS."

Coal-fired power plants produce nearly a third of the world's electricity. Today, they also emit more than half of the world's energy-sector carbon dioxide—the primary driver of climate change. Scientists recommend reducing CO2 emissions dramatically to keep the planet from warming more than 2 degrees Celsius (3.6 Fahrenheit) over its pre-Industrial average.

CCS has seemed like a viable way to do that. Coal is a relatively cheap fuel and the infrastructure to use it already exists—both in the U.S. and in growing economies like China and India. While CCS is still in the research phase, and not commercially used today, it figures prominently into maps of tomorrow's cleaner energy landscape.

"Every major technological, economic and policy study published in the last decade on how to meet the internationally determined target of 80 percent greenhouse gas reduction by 2050 has relied on the large-scale deployment of carbon capture and sequestration (storage)," Skerlos said.

Reports from 2005 and 2012 by the International Panel on Climate Change suggests that CCS could enable between 10 percent and 55 percent of the nation's total carbon reduction by 2100, for example. And just this year, an international study published in PNAS projects that nearly 85 percent of emission reductions by 2050 could come from coal CCS.

These reports and many more like it don't capture the full picture. The current, flawed projections peg the fuel costs of a CCS-equipped coal plant at $29 million per year more than a conventional plant. The new U-M research calculates the additional fuel cost at closer to $126 million, said Sarang Supekar, a postdoctoral researcher in mechanical engineering and first author of the new study.

"Current energy policy studies are based on cost estimates that greatly underestimate the full energy penalty and costs of CCS for ," Supekar said. "Therefore, they overpredict the role of CCS going forward."

Why the discrepancy? Turns out the studies that recommend CCS be a key piece of the world's future energy portfolio rely on numbers from a 1991 pilot study that doesn't completely account for what Supekar calls feedback effects.

"To capture the CO2, you need to generate more energy," Supekar said. "To get this energy, you burn more coal, which creates more CO2 that needs to be captured. So there's this loop that's happening that needs to be accounted for."

The important number, Supekar said, is a plant's overall 'thermal efficiency.' That's the total amount of heat from coal burning that is converted to useful electricity.

The '91 study, by a researcher at the Electric Power Research Institute in Palo Alto, evaluated the engineering and economic feasibility of using CCS to reduce carbon emissions. It concluded that the process was expensive. It also made clear that implementing CCS would require a choice between accepting lower useful power output and, as Skerlos says "confronting the energy loop"—burning more fuel to keep the power output stable.

The early study opted for lower power output. But later studies that cite it didn't interpret that drop appropriately, nor did they mention the energy loop.

To get a sense of the impact of this omission, a new coal plant's typical thermal efficiency is about 38 percent. Current literature—which largely ignores the energy loop—estimates CCS would decrease thermal efficiency to 26 percent. But the U-M researchers say it's more like 16 percent. This efficiency reduction is the cause of the cost increase.

As more CCS test projects have come online, the community has noticed higher-than-expected energy penalties, Supekar said. His study is the first to quantify what those plants are experiencing. Quantifying it is an important step toward figuring out if the technique makes sense from both economic and environmental perspectives. The researchers say it doesn't.

"The one-line conclusion is that coal should stay in the ground," Supekar said. "It's not efficient to take it out, burn it and put it back. Renewables, and possibly natural gas with CCS technology, will be much cheaper and more efficient."

Explore further: New coal plants would tip Earth to dangerous warming: report

More information: Sarang D. Supekar et al. Reassessing the Efficiency Penalty from Carbon Capture in Coal-Fired Power Plants, Environmental Science & Technology (2015). DOI: 10.1021/acs.est.5b03052

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22 comments

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Shootist
2.3 / 5 (12) Dec 02, 2015
Why? It isn't as if it hurts anything.

"The polar bears will be fine". -- Freeman Dyson

In any case, if you don't support nuclear power you don't support carbon free energy.
TheGhostofOtto1923
4.2 / 5 (15) Dec 02, 2015
Too bad we can't burn it there re Centralia.

Run frack tubes through it, set it on fire, remove the heat from the products of combustion, and store the waste in situ.

It sounds hard but maybe it's not. Neither the coal nor the waste would ever have to see the light of day. Maybe I should do a little research...
TheGhostofOtto1923
4.2 / 5 (15) Dec 02, 2015
There's this...

"This produces a gas, a mixture of carbon monoxide, methane and hydrogen, known as syngas.

"The syngas is taken back to the surface, where it is either burned to produce electricity, or turned into liquid fuel such as diesel.

"This technique costs one third of the price of conventional coal," Mr Courtney says. "And that's being generous to coal."

-Not quite the same. Apparently Lenin was a fan.
leetennant
3.6 / 5 (20) Dec 02, 2015
Even if climate change were not a reality, coal should still stay in the ground. It's expensive, dirty, polluting, destroys ecosystems and unsustainable long-term.
ab3a
4 / 5 (20) Dec 02, 2015
I have no problem with keeping coal in the ground as long as people have some idea of what will replace it. Keep in mind it is a very large portion of the base load of the grid, so ephemeral power sources such as wind and solar are not appropriate replacements.

The primary options are Nuclear, Natural Gas, Hydroelectric, or oil energy sources. Choose one or more, but you must choose and you must have it ready to go in a new plant before removing the base load plants for coal.
Mike_Massen
1.6 / 5 (13) Dec 03, 2015
In relation, take a peek at Hazer who are converting LNG to H2 as feedstock for plastics with carbon produced as quality graphite for (Li-Ion) battery electrodes, they just listed their IPO on Australian stock market yesterday, have "a few shares" in a growing position already through commsec (CBA) online trading brokers:-
http://www.asx.co...do#!/hzr
http://www.hazerg...hnology/
https://www.youtu...9JKGEXKI
They're just down the road from me next to University of Western Australia (UWA) but, re insider trading issues I state no relationship with the co at present, though that might well change l8tr ;-)

My day trades since they listed on ASX yesterday, geesh I've been busy !
http://niche.iine...2015.PNG

Whilst many argue irrelevancies on physorg with negligible understanding of engineering & Maths, I exploit maths for stock positioning, smarter than dull jibes here :P
Mike_Massen
2.6 / 5 (18) Dec 03, 2015
ab3a offered
.. a very large portion of the base load of the grid, so ephemeral power sources such as wind and solar are not appropriate replacements
Might have been traditional view but, is not generally the case in more local regions Eg. Around Perth, in Western Australia where I live we have high power demand for air-conditioning just When solar is at its highest with many solar panels on thousands of houses, more planned & a few have battery storage & with Power-wall etc & co's like
http://www.asx.co...do#!/rfx
as local equivalent we have more distributed inputs.

In respect of accommodating & providing base-load buffer, natural gas (plentiful here) can use H2 produced at point of cracking re Hazer process for power whilst only producing graphite, negligible CO2, it can also take in CH4 from biogas & thus be highly carbon negative.

Grid then becomes the key distribution medium with no need for coal or nuclear...
ab3a
3.9 / 5 (15) Dec 03, 2015
Might have been traditional view but, is not generally the case in more local regions Eg. Around Perth, in Western Australia where I live we have high power demand for air-conditioning just When solar is at its highest with many solar panels on thousands of houses, more planned & a few have battery storage & with Power-wall etc & co's like
http://www.asx.co...do#!/rfx
as local equivalent we have more distributed inputs.


What you're describing is not base load.

In respect of accommodating & providing base-load buffer, natural gas (plentiful here) can use H2 produced at point of cracking re Hazer process for power whilst only producing graphite, negligible CO2, it can also take in CH4 from biogas & thus be highly carbon negative.

Grid then becomes the key distribution medium with no need for coal or nuclear...


It can, but is it built up yet? Is it understood well enough to rely upon for keeping the grid going?
antigoracle
3 / 5 (14) Dec 03, 2015
Ha..ha.. Mutterin' "Bonobo monkey" Mike is a Day Trader.
Hope those he stole from have spread the word, since he'll soon be looking to replenish his losses.
Maggnus
4.7 / 5 (12) Dec 03, 2015
I have no problem with keeping coal in the ground as long as people have some idea of what will replace it. Keep in mind it is a very large portion of the base load of the grid, so ephemeral power sources such as wind and solar are not appropriate replacements.

The primary options are Nuclear, Natural Gas, Hydroelectric, or oil energy sources. Choose one or more, but you must choose and you must have it ready to go in a new plant before removing the base load plants for coal.


But is that not the whole point of the recommendations of the IPCC and other scientific bodies? That is, let's take steps to move us away from fossil fuels as quickly as possible?

Or do you have an argument with "as quickly as possible"?
Zzzzzzzz
2.1 / 5 (15) Dec 03, 2015
There's this...

"This produces a gas, a mixture of carbon monoxide, methane and hydrogen, known as syngas.

"The syngas is taken back to the surface, where it is either burned to produce electricity, or turned into liquid fuel such as diesel.

"This technique costs one third of the price of conventional coal," Mr Courtney says. "And that's being generous to coal."

Syngas is being produced today, in a number of locations at a number of power plants. For example, a power plant recently built in Indiana drives syngas out of coal. The power block is approx. 1/10th of the plant, the rest is the Syngas production plant. Natural gas prices are so low that the plant is running on that, and the Syngas plant sits idle. The Syngas process house load is quite high, so in with US current natural gas prices Syngas is very expensive. I doubt your fracking tube scenario will result in usable Syngas BTW, I've seen GE's process up close.....
ab3a
4.3 / 5 (12) Dec 03, 2015
But is that not the whole point of the recommendations of the IPCC and other scientific bodies? That is, let's take steps to move us away from fossil fuels as quickly as possible?

Or do you have an argument with "as quickly as possible"?


The argument I make are an issue of the limits of what is practical and safe to engineer, construct, and operate. You can interpret that any way you like, but it is the reality we face. Engineering at power levels like this should be done with the utmost level of conservative design or risk disaster that threatens our civilization. Of course the IPCC makes the argument that we're doing that anyway. However, if they are to be taken at face value, then at least it will be a knowable and comprehensible disaster compared to the risks of a large scale failure of a high power, flawed design.

Feel free to prove me wrong, but do it at a scale where the only lives you risk are yours.
Mike_Massen
1.6 / 5 (14) Dec 03, 2015
antigoracle said
.. Mike is a Day Trader
Not exclusively, mainly Electronic Engineer & Food Scientist, dabble progressively since I sold out Palladium stocks 1987 re cold fusion upon analysing power density issues & bought a house ie Nice profit, now preparing for positions with several Aust listed stocks Eg
http://www.asx.co...sjh9.pdf

antigoracle stupid again claims
Hope those he stole from have spread the word..
Not stolen anything, prove your dimwitted claims ?

Robotically same as the nasty Stalking utter dimwit Uncle Ira confusing idle claims by likewise redneck idiots with anything like Evidence !

ie Uncle Ira failed dismally to even THINK to check with site admins of one web forum, you're the same character/low IQ guise as Water_Prophet, TheGhostofOtto1923, jeffensley, ubavontuba all with huge character flaws re confirmational bias, show yourselves up as immensely stupid, dull like fish in a barrel :P

Learn Physics !
Uncle Ira
4.3 / 5 (16) Dec 03, 2015
ie Uncle Ira failed dismally to even THINK to check with site admins of one web forum


Mike-Skippy failed miserablly when all he do about the link I posted up was stamp his feets and threaten to take ol Ira-Skippy to courts. (Also write some really silly emails to the nice peoples at physorg too.)

I wonder what silly thing Mike-Skippy will when I start poking fun at Hazer-Skippys who don't really make anything?
Uncle Ira
4.3 / 5 (18) Dec 03, 2015
P.S. for Mike-Skippy who doesn't think about some people like Ira who has a super CIA type NASA grade computer when he posts his linkums to brag a little.

HazerGroup Ltd (4employees)

Sytructural Monitoring Systems (no employees) careful with this one, they made up a name that was really close to a big multinational type of company.

Star Property Management (2 employees)

Strategic Elements (1 employee or maybe 0 employees)

Nexus Minerals Ltd (1 employee or maybe 0 employees)

Canyon Resources Ltd (1 employee or maybe 0 employees)

Straight Lines Consultancy Ltd (2 employees)

Mac Equity (3 employees and a bunch of hanger-arounders)

Those awesome companies have the exact same address.

Suite 7, 29 The Avenue Nedlands WA 6009 According to Google-Skippy's look at the street view, they must be pretty crowded in the Suite 7 because it's a tiny little building.

Mike-Skippy would be lot happier if he just left Ira out of his postums, eh?
jim_xanara
1.8 / 5 (15) Dec 03, 2015
The problem with antirational is that we're not speaking his language. I'll make an attempt to reply to him in kind.

antigoracle 1.0 / 5 (122) Dec 03, 2015

I'm terrified of Al Gore!


antigoracle 1.0 / 5 (120) 2 minutes later

You are all idiots to not be terrified of Al Gore!


antigoracle 1.0 / 5 (153) 2 minutes later

I'd rather be painted in honey and left tied up on a fire ant mound than shake hands with Al Gore!


antigoracle 1.0 / 5 (153) 2 minutes later

Shite! I'm crapping my pants. I think Al Gore is behind all this!


Hey, Chicken Little, grow a brain and get therapy for your Gore-phobia. We're not here to solve your mental problems. Feckless Al isn't going to tow your trailer away.
jljenkins
2.8 / 5 (11) Dec 03, 2015
IMHO, the current pseudonyms for that anonymous coward have been pretty good, and rank as follows:
1- "1.Loser"
2- "Anti-science"
3- "Anti-rational"

That first one is a veritable ROFLMAO. No truer statement has been made in these pages. It really captures it all. Even if I imagine trying to be a hopeless troll haranguing my least liked cause site, I still would have enough self respect to find greener pastures if I got voted 1/5 EVERY time I opened my mouth. There's a lot of mental illness on display here. Only explanation.
gkam
1.5 / 5 (17) Dec 04, 2015
Somebody ask Ira if he understands carbon capture, the real issue here, not personalities.
gkam
1.5 / 5 (15) Dec 04, 2015
If you want to see some technologies which can eventually make carbon capture unnecessary, go here:

http://www.utilit.../410242/
Mike_Massen
1.6 / 5 (13) Dec 04, 2015
In Australia we have http://redflow.co...rt-grid/
& is also on the Australian Stock Exchange through a mining co shell
http://www.asx.co...do#!/rfx

Suffice to say they are on my list of current stocks & growing too :o)

My eldest son, who completed a degree in chemical engineering 2013, has been keen on Hazer & advised me re the viability of their system as its "his thing":-
http://www.hazerg...hnology/
both he and I have a holding from the IPO which has since increased despite their listing on the ASX just last Wednesday the 2nd Dec 2015
http://www.asx.co...do#!/hzr

& as consequence in discussions with Chevron he's been offered a PhD over 3-4 years
at Curtin University in Bentley, Western Australia, professors offer letter just arrived
on same day Hazer first listed on the ASX - yow !

All great fun but, sad that there are a few still far behind the eightball who fail @ Physics
Uncle Ira
4.3 / 5 (18) Dec 04, 2015
Somebody ask Ira if he understands carbon capture, the real issue here, not personalities.


Somebody ask glam-Skippy why he don't ask Ira-Skippy him self. And while you are asking glam-Skippy about that also ask him why thinks Ira-Skippy has to go by different personalities rules than he does.

Oh yeah, I almost forget. For you guys slow on the uptake like glam-Skippy and the Mike-Skippy, that means how come you whine and cry about rudeness and personalities and at the same time almost every postum you put up is dripping with rudeness and personal insults. If they did not care for Ira-Skippy's style, then they should have not gotten rude and insulting to start with Ira-Skippy. There is a saying about it that has to do with living in a hothouse and flinging rocks at your neighbors, eh?
SuperThunder
1.6 / 5 (13) Dec 06, 2015
For you guys slow on the uptake like glam-Skippy and the Mike-Skippy, that means how come you whine and cry about rudeness and personalities and at the same time almost every postum you put up is dripping with rudeness and personal insults.


My neighbors used to have chihuahuas (pronounced chee-hoo-ah-hoo-ahs), which are cats for people who hate cats, and they would let them roam in packs in the neighborhood at night. They would run up on people coming in and out of their homes and bark and growl like they were going to attack, but when someone took a step towards them they yelped and screamed like they were being disemboweled and ran to a safe distance. Then, they would repeat. Eventually, the neighborhood proper-cats culled most of them.
Some humans also become super aggressive until challenged, then pretend cry and run off to a "larger adult" to lie and try and get their way. Somewhere in evolution violent cowardice branched off of sentience and ran with it.

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