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This sounds downright revolutionary. Could someone with domain knowledge comment if this is really such a new thing?

The press release says,

>In chemical looping, the coal isn't burned with fire, but instead chemically combusted in a sealed chamber so that it doesn't pollute the air. A second combustion unit in the lab does the same thing with coal-derived syngas, and both produce 25 thermal kilowatts of energy.

How much coal does it take to produce those 25 kW? You'd think efficiency is what most readers would want to hear about at this point because everything else sounds pretty great.

A page linked [1] from the press release states that

>New technologies that use fossil fuels should not raise the cost of electricity more than 35 percent, while still capturing more than 90 percent of the resulting carbon dioxide.

but it is unclear if this is mostly due to the price of extra coal or the equipment itself.

[1] http://researchnews.osu.edu/archive/looping203.htm




You'd think efficiency is what most readers would want to hear about at this point because everything else sounds pretty great.

It's necessarily less efficient than coal power without CO2 capture. From these slides [1] they estimate 35%, vs. 39% for a conventional coal plant, and 29% for a different type of CO2 capture (post-combustion CO2 scrubbing with monoethanolamine [MEA]).

...but it is unclear if this is mostly due to the price of extra coal or the equipment itself.

Mostly equipment/capital [1].

[1] http://www.netl.doe.gov/publications/proceedings/12/co2captu...


coal isn't burned with fire, but instead chemically combusted

I'd like some clarification on the difference between "fire" and "chemical combustion"


One definition of "fire" demands "oxygen from the air":

https://www.google.com/search?q=define+fire&oq=define+fi...

The fuel here doesn't react with air, but with a solid oxidiser (Fe2O3). It's a solid-solid reaction, whose products are gases (CO2 and H2O). Just like a solid-fuel rocket.


And how is CO2 form Fe2O3 different than CO2 from the air? Is it just that it is easy to capture? Then what?


It's not different, but it's a pure gas and not mixed with a ton of nitrogen that air combustion exhaust would be. That makes it trivial to capture (literally just pump it through a compressor into a tank).

One important point, though, is that the sequestration problem is not actually addressed here. This just gets you conveniently-produced tanks of CO2 (or crates of dry ice, whatever). What you do with that to keep it out of the atmosphere is still an open problem.


Thank you, now it makes some sense. These press releases are next to useless.




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