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Are those two the biggest problems when it comes specifically to biomass? I hear biomass advocates all over the place saying they're the solution, saying: "we'l

Are those two the biggest problems when it comes specifically to biomass? I hear biomass advocates all over the place saying they're the solution, saying: "we'll run entirely on carbon-neutral corn-derived ethanol and the poo from our vegan diets". Wow, that'd be great, but where are the numbers? Many of these claims go without physics-first principles and real numbers to back them up. For instance, using algae, we'd need an incredibly massive commitment of funds to install scrubbers on all the plants across the world. Even if we did that over the next 30-50 years, which we really can't yet because the tech isn't ready, even if a miracle occurred and we did that, that doesn't solve the existing CO2 heating the planet or the negative feedback loops. IMO, the real problem with biomass is the sheer scale of the energy system, it's far too large of an industrial base already for algae scrubbers to be effective. IMO, we need planet-cooling measures, increasing cloud cover, increasing albedo, somethjing to prevent heating and the vicious feedback loops in the arctic and elsewhere. Then, we also need to deal with the CO2, which will still be around even if we reduce insolation and heating. I don't know if algae or CCS or some other method will be used for that, but I see that as secondary to the "easier" cooling mechanisms.

dredmorbius 8y ago
For waste-stream based fuels, consider first that the upper bound on potential is the incoming feedstock, that is, food, and nets to something like 25% of its energy potential. And the feedstock is bounded by net primary primary productivity, also referred to as the photosynthetic ceiling. It turns out that humans already lay claim to 20% of this. Replacing fossil fuels (a prerequisite to acheiving net zero emissions) would require another 20% of NPP, an unlikely scenario. Using crop yields and land area, one quickly realises that under all but the rosiest scenarios, more land is required for biomass fuel production than exists in major technological and industrial nations. So, no, biomass is not sufficient to sustain present per-capita energy use and populations. https://old.reddit.com/r/dredmorbius/comments/2cvap7/the_intractable_problem_of_biomass_for_fuels_is/ https://old.reddit.com/r/dredmorbius/comments/2cvap7/the_int...
- aoner 8y ago
  you can also use the sea with wastewater as feedstock: https://www.nasa.gov/centers/ames/research/OMEGA/index.html https://www.nasa.gov/centers/ames/research/OMEGA/index.html
  - dredmorbius 8y ago
    Interesting, though still bounded by the photosynthetic ceiling, and you're competing with all other marine life.
maxbond 8y ago
To summarize my thoughts on the topic, no we cannot use food crops and arable land for energy production, no biomass is not sufficient, and a nexus of solutions will be required. Managing and integrating those solutions is where the complexity comes into play. If you're deploying a nexus of solutions it doesn't matter as much if some of the technologies are immature, you can structure them to cover each other's deficiencies (similar to the computer security concept of defense in depth). I was mostly responding to the original poster's feeling of hopelessness and arguing that solutions are possible and are being developed.

dredmorbius 8y ago

For waste-stream based fuels, consider first that the upper bound on potential is the incoming feedstock, that is, food, and nets to something like 25% of its energy potential. And the feedstock is bounded by net primary primary productivity, also referred to as the photosynthetic ceiling. It turns out that humans already lay claim to 20% of this. Replacing fossil fuels (a prerequisite to acheiving net zero emissions) would require another 20% of NPP, an unlikely scenario. Using crop yields and land area, one quickly realises that under all but the rosiest scenarios, more land is required for biomass fuel production than exists in major technological and industrial nations. So, no, biomass is not sufficient to sustain present per-capita energy use and populations. https://old.reddit.com/r/dredmorbius/comments/2cvap7/the_intractable_problem_of_biomass_for_fuels_is/ https://old.reddit.com/r/dredmorbius/comments/2cvap7/the_int...

aoner 8y ago
you can also use the sea with wastewater as feedstock: https://www.nasa.gov/centers/ames/research/OMEGA/index.html https://www.nasa.gov/centers/ames/research/OMEGA/index.html
- dredmorbius 8y ago
  Interesting, though still bounded by the photosynthetic ceiling, and you're competing with all other marine life.

maxbond 8y ago

To summarize my thoughts on the topic, no we cannot use food crops and arable land for energy production, no biomass is not sufficient, and a nexus of solutions will be required. Managing and integrating those solutions is where the complexity comes into play. If you're deploying a nexus of solutions it doesn't matter as much if some of the technologies are immature, you can structure them to cover each other's deficiencies (similar to the computer security concept of defense in depth). I was mostly responding to the original poster's feeling of hopelessness and arguing that solutions are possible and are being developed.