The Precarious Future of Coal

The problem is - we ARE using up the carbon.  CO2 is the lowest form of energy in which carbon exists, so it is not possible to extract energy from CO2.  If carbon is used as energy source, we will always end up with CO2.  Renewable processes either use an external energy source to convert the CO2 to molecules of higher energy (like photosynthesis using solar energy), or use non-carbon processes (solar energy to electricity, nuclear energy etc.)  Irrespective of where the carbon comes from, we will release CO2 from a carbon-based energy process.  If we want to minimise CO2 emissions, we must either replace the energy source, or maximise the efficiency of the total process (i.e. minimise energy losses ALL THE WAY to final use).  The latter will not reduce CO2 per se, but will maximise the amount of usable energy per molecule of CO2 created.

Currently, the main source of CO2 use is still photosynthesis, and ideally we need to reduce the amount of CO2 released only down to the amount of CO2 that can be processed by photosynthesis (sounds easy, but in fact this is a huge challenge!)

The link to the report I read is
uregina.ca/ghgt7/PDF/papers/nonpeer/139.pdf

We seem to be neglecting the volume issue.  Gases, even under extreme pressure occupy significantly more volume than the solids/liquids they replace.  It's still the same number of Carbon atoms.  Not to be too funny, but what happens when the ground "burps" and mass quantities are re-released?

My money's still on bio-cycling with algae as a direct C-reduction vector back to usable oil.

I am involved in driving mine shafts by freezing the soil around the shaft to form a temporary structure while a permanent structure is built.

I am interested in carbon doxide as R-744 (a refrigerant).  At 2000 feet below ground  the pressure of a liquid column carbon dioxide is about 800 psi higher than it is on the surface and at this pressure it will not evaporate down the hole.  It should be easy and cheap to sequester liquid carbon dioxide at a depth where it will not evaporate.

"Economists (and freedom lovers) prefer distributed sources of power (and wealth) over concentrated, centralized power;"
Does this refer to the pitting of the "haves" Vs. the "have nots"?

You may be right, in the end.  But cleaning up the stack emissions de minimus presumes that the other stuff, especially mercury, would be cleaned up too.

The CO2 in my intuition is the stuff that would be really hard to get rid of because of volume.  But maybe I'm wrong.  Maybe using biological means, or catalysts, CO2 could broken down and then recombined in some form at leisure.

Seems to me that carbon sequestration (also could apply to petroleum and natural gas combustion) could possibly be a significant element in a suite of low and high tech responses to the need to cut greenhouse gas emissions of all types.

A big problem I see with coal is all those open pit mines.  And has anyone studied the contributions of methane gas emissions attendant to various types of coal mining opertions and THEIR contribution to global warming.  Especially now that it appears that the contribution of methane deriving from cattle farts--excessive concentration of corn in the diet of cattle (substituting for grass)--may actually be a significant contribution to greenhouse gases.  

Also, off the subject, consider positive effects of niche markets for some technologies.  Thousand mile stretches of virtually uninhabited desert coasts (in Chile, for example, Australia, or perhaps the Arabian Peninsula) could be markets for small scale solar electrical plus desalination systems in very small communities, scientific outposts etc.

Now they depend a lot on very inefficient generators and water trucked in, if that. In solar power/desalination systems a cistern can even be an energy storage device.

Very high initial capital costs (unless one could mass produce standardized multifunction units) but relatively low operating costs.  To become common, however, such systems would need to be nearly maintenance free (A cousin--a mining engineer from Chile--just visited us in New York; that's why the energy needs of such environments is on my mind). Systems would need to function nearly unattended for maximum efficiency.  But maybe way too off the subject.

A drop in the bucket to quench global warming?  Yes, but if combined with billions of others, an element of a fair start. 

There are no silver bullets.

I know some big coal burning companies are looking into this.  Although the amounts of toxic compounds, like Hg, are small, due to the huge amounts of coal burned in some processes, and due to factors like reflux, these compounds are concentrated to amounts that become significant.  However, extracting them in economically vialbe processes still remains a technical difficulty, therefore one of the schools of thought is still to "make them inactive" (e.g.encapsulation in inert material) and dump them responsibly.  But I agree, finding a use for elements contained in toxic waste is far better than dumping toxic waste.  (This opens another debate - should one dump organic molecules, or oxidise them to CO2 and "dump" the CO2?  Which option will be the least harmful IN THE LONG RUN?)

I scored 70% on the test. That said, the most likely proposal for taxing carbon is to place a tax on the fuel at the well-head (oil) or the mine (coal). Wouldn't this discourage companies from investing in expensive carbon removal or sequestering?