3 ms·

Even though GP's mechanism doesn't explain global warming, it does explain the nigh-impossibility of developing technology that can carbon-capture us out of thi

Even though GP's mechanism doesn't explain global warming, it does explain the nigh-impossibility of developing technology that can carbon-capture us out of this mess. Biomass is basically solar-powered carbon sequestration. If each year of fossil fuel consumption corresponds to the energy of 400 years of biomass, and we've been burning "too many" fossil fuels for 50 years, then to get out of this mess we would have to cover 50x400 = 20,000 Earth's with solar panels hooked up to carbon capture machines. It's way worse, if course, because photosynthesis is more efficient than solar panels, and there's inefficiencies in carbon capture, but you get the idea! We've used up way, way, WAY too much energy making tiny explosions and now we have to undo each and every one of them.

throwaway09223 5y ago
Your example incorrectly assumes the entire solar constant went toward carbon sequestration and this is obviously not the case. The overall energy efficiency of the natural photosynthesis to sequestered carbon process is not inherently more efficient than man-made alternatives. The efficiency of the PV cell is just one small factor. A much more accurate way to calculate sequestration potentials is to measure their energy cost and multiply by available energy.
- el_nahual 5y ago
  It's just a Fermi estimate. Feel free to multiply/divide by ten (or even 100!) in either direction. The main point is that we're not going to carbon capture our way out of this--at least not with anything resembling modern technology.
  - philipswood 5y ago
    I'd put my money on directly modulating incoming solar radiation instead From the first time I saw the animations of the planned Starlink fleet, I started wondering if one could use a satelite fleet to manage incoming solar radiation. I've commented about it a few times before. https://news.ycombinator.com/item?id=18474244 https://news.ycombinator.com/item?id=18474244
  - throwaway09223 5y ago
    But your estimate is demonstrably off by at least a factor of ten thousand. The thrust of this paper is that it takes 90 tons of ancient biomass to result in 1 gallon of gasoline. This is a reduction of 30,000 to 1. This is the opposite of an efficient system. The vast majority of solar input and related carbon captured from the atmosphere by ancient plant matter is not being utilized by modern fossil fuel systems. The point of this paper is that the ancient photosynthesis to fossil fuels process is incredibly inefficient. The "400 years" isn't indicative of the energy we're consuming today -- it's indicative of the extremely low percentage of solar energy that ends up captured inside fossil fuels. We absolutely can carbon capture our way out of this. Again, you can do some pretty basic math on known sequestration techniques to disprove your conclusion.

throwaway09223 5y ago

Your example incorrectly assumes the entire solar constant went toward carbon sequestration and this is obviously not the case. The overall energy efficiency of the natural photosynthesis to sequestered carbon process is not inherently more efficient than man-made alternatives. The efficiency of the PV cell is just one small factor. A much more accurate way to calculate sequestration potentials is to measure their energy cost and multiply by available energy.

el_nahual 5y ago
It's just a Fermi estimate. Feel free to multiply/divide by ten (or even 100!) in either direction. The main point is that we're not going to carbon capture our way out of this--at least not with anything resembling modern technology.
- philipswood 5y ago
  I'd put my money on directly modulating incoming solar radiation instead From the first time I saw the animations of the planned Starlink fleet, I started wondering if one could use a satelite fleet to manage incoming solar radiation. I've commented about it a few times before. https://news.ycombinator.com/item?id=18474244 https://news.ycombinator.com/item?id=18474244
- throwaway09223 5y ago
  But your estimate is demonstrably off by at least a factor of ten thousand. The thrust of this paper is that it takes 90 tons of ancient biomass to result in 1 gallon of gasoline. This is a reduction of 30,000 to 1. This is the opposite of an efficient system. The vast majority of solar input and related carbon captured from the atmosphere by ancient plant matter is not being utilized by modern fossil fuel systems. The point of this paper is that the ancient photosynthesis to fossil fuels process is incredibly inefficient. The "400 years" isn't indicative of the energy we're consuming today -- it's indicative of the extremely low percentage of solar energy that ends up captured inside fossil fuels. We absolutely can carbon capture our way out of this. Again, you can do some pretty basic math on known sequestration techniques to disprove your conclusion.