My response to the comments on my previous post. I'll apologize for the way I express myself. I'm an engineer, not a writer. I won't apologize for the analysis.
First a quote: "The future for carbon separation in coal-fired power plants is in integrated coal gasification combined cycle, where CO2 is separated before combustion."
And a response: WTF? So the proposal is to "pre burn" 60% to 80% of the fuel content of coal?
The typical carbon content for coal (dry basis) ranges from more than 60 percent for lignite to more than 80 percent for anthracite
http://www.eia.doe.gov/...
- Heat to Steam Power
http://www.iop.org/...
Calculate the maximum theoretical thermal efficiency of a coal-fired power station that heats steam to 510°C and cools it in a condenser at 30°C.
Answer: Maximum efficiency = E.
E = (THOT – TCOLD)/THOT
E = [(510+273) – (30+273)] / (510+273)
E = 480 / 783
E = 0.61 or 61%
The actual efficiency will be smaller. Students should consider why.
- Steam Power to Electricity
Mechanical losses. Let’s estimate the conversion from Steam Power to Electricity at 90%.
E = 61% x 90% = 54.9%
- Electrical Maximum Power Theorem
http://powerelectrical.blogspot.com/...
The theorem states that in a circuit maximum power is transferred from source to load when the resistance of the load is same as that of the source. Rsink = Rsource. (True for power station as the source resistance and sink resistance approaches zero.)
If Rsink = RSource then efficiency = 0.5
E= 54.90% x 50% = 27.45.
Due to a great amount of engineering, this efficiency is actually about 31% to 33% in a modern stream electrical generation station.
31% of the energy from burning coal is delivered as electricity to the grid. Much less gets to the consumer.
Other losses
Enew is the "new green coal", Eold is the existing coal fired stations.
- Air cooling losses, v evaporative cooling
Enew = 31% x 90% = 27.9%
Eold = 31%
- Sequestration or Carbon capture cost
This is a range, because No large scale carbon capture (sequestration) plants exist, and large scale engineering projects have a track record of cost overruns and low efficiencies. 15% to 35% of the electricty generated is requires to compress and liquify the carbon dioxide. My personal opionion is this number is actually in the 75% to 90% range.
Enew = 27.9 % x 85% = 23.375% to Enew = 27.9% x 65% = 18.13%
Eold = 31%
- Transmission Losses
Typically 50% of the electricity is lost in transmission – which is the reasons for High Voltage DC lines (Less current and no phase lag losses).
Enew = 9% to 11.69%
Eold = 15.5%
At best about 50% to 75% increase in the price of electricity to consumers from Sequestered Electricity Generating Stations, ASSUMING (5) IS CORRECT.
I’d expect the cost of Electricity to at least double.