In the past few years I've noticed a tendency for people to assume that a hydrogen economy would save us (but where do we get the energy on a scale big enough to make the quantity of H2 that would be required?), that fuel cells would save us (that technology is progressing but, again, when will we get to a large scale?), and that carbon sequestration is the simple answer to the gigantic contribution coal combustion makes to global warming.
An article in the June 11 NY Times discusses the vast amounts of pollutants coal combustion in China produces. There it causes 400,000 premature deaths per year. Burning all that coal has given more people more electricity, so they are leading better lives--a tradeoff the growing Chinese middle class is more than willing to make.
If the US starts turning coal into liquid automotive fuel, our 200 years of coal reserves will rapidly shrink to a matter of decades.
Plan9 on Mon Jun 12th, 2006 at 10:26:44 AM EDT wrote
"I usually see carbon emissions measured in tons. What would be the annual total of CO2 requiring sequestration in tons?"
A metric ton is one million grams. A Petagram is a million metric tons. So 37 petagram CO2 is 37 million metric tons. For every ton of coal we mine, we have to bury 3.7 tons if CO2 in such a manner as to isolate it from the atmosphere for hundreds of years.
"In the past few years I've noticed a tendency for people to assume that a hydrogen economy would save us (but where do we get the energy on a scale big enough to make the quantity of H2 that would be required?), that fuel cells would save us (that technology is progressing but, again, when will we get to a large scale?),..."
We must make the energy to make hydrogen for the fuel cells, and I am afraid that increasing portions of our energy will come from coal.
"...and that carbon sequestration is the simple answer to the gigantic contribution coal combustion makes to global warming"
I see no serious possibility today of effectively burying several tens of millions of metric tons of CO2 per year.
"An article in the June 11 NY Times discusses the vast amounts of pollutants coal combustion in China produces. There it causes 400,000 premature deaths per year. Burning all that coal has given more people more electricity, so they are leading better lives--a tradeoff the growing Chinese middle class is more than willing to make."
Perhaps, until they run out of clean air and fresh water.
"If the US starts turning coal into liquid automotive fuel, our 200 years of coal reserves will rapidly shrink to a matter of decades."
I think this will happen, worldwide, implying for example, that 10 million Bangladeshis must relocate every decade. Not to speak of more disastrous effects.
sidd
