We can't "regrow" coal in the same way (across reasonable time scales). (Although burning coal, and planting a corresponding amount of trees and never cutting them down is also an option)
No really, how? Have you invented some new process for long-term carbon sequestration from waste biomass?
These are hard problems that don't lend themselves well to the HN-preferred format of one-line tech solutionism. If it were as simple and easy as all that, we wouldn't be in this crisis to begin with.
There's no need for any sort of "new process for long-term carbon sequestration". We just need to stop taking carbon that is in the process of being sequestered by natural cycles and putting it back into the atmosphere. This is an economic challenge not a technical one.
Recent work[1] has argued that microbal and fungal diversity did not play a significant role in the development of coal deposits, but rather it was a combination of environmental effects that generated swamps where anaerobic conditions prevented plant decay. These conditions still exist today, we are just actively removing them.
Either way you haven't made a case, or provided sources, for why it wouldn't work.
Some methods are apparently snake oil[1]. But others, such as pumping into saline aquifers[2] may be viable (the source on that is naturally suspicious).
1. https://grist.org/article/rule-four-of-offsets-no-enhanced-o...
2. https://www.spe.org/industry/carbon-capture-sequestration.ph...
This perfectly illustrates the problem with overemphasis on 'carbon accounting.' It leads well-meaning people advocate cutting down the last shreds of wilderness on environmental grounds, because this pernicious carbon oversimplification says we're not "getting something" out of that wilderness land.
In truth wilderness cleans air and water pollution, wetlands and forests buffer precipitation to prevent floods and droughts, and large-canopy trees ~single-handedly cycle rain back up and power the terrestrial water cycle (you heard me right, trees cause ~all inland rain). Even if you prefer to exsanguinate nature and reduce it to bean-counting 'ecosystem services,' surprisingly humans do get something from letting carbon rot blissfully undisturbed on a forest floor somewhere.
So it's not quite accurate to say "the carbon will return to the atmosphere without having any energy harvested along the way" -- bugs and fungi are "getting something" too! This seems insignificant, but such decomposition organisms play major ecosystem roles in breaking down air and water pollutants.
To bastardize Arthur C. Clark, "nature is indistinguishable from sufficiently advanced technology."
> Granted, we are speeding up the cycle by burning it now vs rotting over time, [but] the balance of carbon is the same.
Except in this case, that time variable is very important! It's basic math:
The rate of carbon sequestered per hectare per year is constrained by sunlight and photosynthesis, so the only parameter we can tweak to achieve further gains is the time: how long is the average carbon atom removed from the atmosphere? 1 year? 100 years? Because in the latter case, the equilibrium amount of carbon that can be stored (tonnes/hectare) is 100x greater. Try getting a 100x improvement in photosynthesis!
Humans have so far released ~1,600 gigatonnes from fossil fuels, and Earth has 11.9 gigahectares of non-tundra land. Dividing, that requires 134 tonnes of additional carbon stored (as trees, soil, buildings, somehow) per hectare. Forests store up to 600 tonnes/hectare, so this at least seems physically and thermodynamically achievable (unlike most "carbon sucking machine" proposals).
If carbon is stored in biomass at 5 tonnes/ha/year, to sequester 134 tonnes/ha, again by simple division we must store that carbon for an average of at least 27 years. Or longer, if you want to 'alter' less than 100% of Earth's surface. :)
Obviously the only practical way to implement this is to integrate this carbon storage in our agricultural and built landscapes. What we need is high-carbon-density agricultural systems, suburbs, and cities.
Especially when grown specifically, biofuels may have a strong net negative effect as conversion from forest/swamp to arable land releases a huge amount of stored carbon. Burning a forest to grow palm ethanol is a step in the wrong direction.