Whether that's a commercially viable amount or not, I have no idea. And your last point, I agree with. We should certainly make the coal industry include externalities in their price as much as feasible, making for a (more) fair energy market.
No, we should mock people for entertaining the idea and being unable to muster enough knowledge and reason to start being very skeptical. It's basically the same sort of estimation that happens when watching Shark Tank and wondering, "Well, that's a nifty product. What are the margins?" Basic Thermodynamics isn't too far off from accounting. There's a big difference between "works technically, in theory" and "would it work in the real world?" Essentially, you're saying it's okay that people can spout basic science, but still can't apply it in their actual lives in a market economy. Shouldn't that be the lower bar?
I'm saying that the idea is completely compatible with science, and at a cursory inspection seems like a completely viable solution. There's no education problem involved in at least discussing it.
Is coal at ~70% efficiency a better solution than nuclear, solar, wind, hydro, etc.? I'm not sure, but that is sure as hell not snake oil.
If it takes you 30% of the initial energy to get to the heat->electricity phase, then the heat->electricity phase receives 70% of the initial energy. From that point, a 35% efficient transfer means 24.5% efficiency from the initial energy.
http://www.iea-coal.org.uk/site/2010/blog-section/blog-posts...?
My issue with the coal industry is they pushed back on any sort of regulation for 30yrs instead of innovating.
Imagine what they could have done if they had invested in clean coal technology in the mining areas of the US.
Instead, they are now complaining because they got lazy and solar and wind capitalized on their inability to get the job done.
Liquid CO2 boils away (solid CO2, i.e. "dry ice" sublimates) as it cools, so it'll still be released into the atmosphere.
Until you get into the particulars of burning coal and CO2 capture with feasible equipment (which aren't simple), for all you know the loss is 0.1%
The only way that Clean Coal will work is by applying massive subsidies.
I, for one, support these massive subsidies as long as they are applied by MWh produced and are available to all producers, not just the coal burners.
This tells me nothing about economic viability - for a while the solar panel efficiency was rated in single digit percentages, and even today it's low double digits.
With that 30% waste incorporated what is my final cost of a kWh produced by an electric plant that's running 100% on clean coal?
But the real problem is the carbon, which when burned produces CO2. If you take the carbon out of coal, you don't have coal anymore.
"The current episode of global warming is attributed to increasing emissions of CO2 and other greenhouse gases into Earth's atmosphere. " - https://en.wikipedia.org/wiki/Carbon_dioxide_in_Earth%27s_at...
Also in the first few lines of wikipedia you will see that C02 is only 0.04% of the atmosphere. This small percentage has huge effects.
We get energy from coal by burning it then extracting some of the heat. The waste products are basically carbon dioxide and heat.
Clean coal is about capturing that carbon dioxide, which means spending energy to separate the CO2 from other gasses, then liquefy it.
This sequestration process costs about 30% of the energy originally extracted from the coal.
I fully support clean coal since it increases the price of coal fired electricity, meaning coal plants will become uneconomical sooner.