At first it seems counter productive to deliberately go to lower temperatures and lower overall thermodynamic efficiencies but a charcoal process could be designed to heat a boiler or evaporator in a low to intermediate temperature power plant.
The lower temps would allow for lower cost materials, designs and construction. A Rankine cycle has a good Carnot efficiency at low delta Ts so the overall efficiency mught not be too bad.
Since part of the purpose of the plant is to sequester carbon it isn't all that important to tweak fuel efficiency with the high temp. super heat cycle common at coal fired plants.
The government would then buy the charcoal, mix it with a trace taggent to prevent reselling fraud, and then sell it as a soil amendment, to clean up ground water leaching from toxic sites or just dump it in a landfill to sequester the carbon.
The charcoal stacks could be used as fuel in emergencies or if AGW somehow reverses.
A "Cash for Charcoal" program would create an incentive to gene splice some highly efficient fast growing bio fuel that could be grown in sea water.
The more grid energy you use the more carbon you sequester for a sustainable high economic growth rate.
Who says thermo is the dismal science?
Bret Cahill
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