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One of the Charm co-founders here. Great questions, and you're correct the point is to find an economically profitable basis for sequestration. 1. In North Ame

by pkrein 8y ago

One of the Charm co-founders here. Great questions, and you're correct the point is to find an economically profitable basis for sequestration. 1. In North America alone we have 32,000 gigatons of geological sequestration storage capacity... about 900 years of global carbon dioxide emissions. https://en.wikipedia.org/wiki/Carbon_capture_and_storage https://en.wikipedia.org/wiki/Carbon_capture_and_storage 2. We looked at generating electricity, and many others have built and operated biomass-to-electricity plants. The economics don't work out... electricity is very cheap. Most of the biomass-to-electricity plants in California are closing up shop now. 3. Hydrogen may be a byproduct of some plastics manufacturing processes, but not nearly on the scale consumed. 4. Yes, hydrogen is a (cleaned up) biochar volatile! We consume most of the biochar itself as the energy source for heating the gasifier. Any excess biochar will be sold as soil amendment.

hanniabu 8y ago
What's the flow rate you guys want to achieve and what's the allowable variance?
- pkrein 8y ago
  Flow rate of biomass or hydrogen? Per unit we expect roughly 10-20 tons per day of biomass, and 0.5-1 ton per day of hydrogen. Allowable variance is low, but depends on the customer.
  - hanniabu 8y ago
    Was referring to the biomass. So at 10-20 tons per day, I'm guessing you go through a hopper worth roughly every 10-15min?
    - chimere 8y ago
      10-20 tons per day is commercial scale. The prototype in this article was much smaller - running around 0.3 t/day.
chimere 8y ago
Also the USGS has this super cool map of potential CO2 storage in (under) the US: https://co2public.er.usgs.gov/viewer/ https://co2public.er.usgs.gov/viewer/
HillRat 8y ago
Fascinating stuff. If you’re using BECs rather than waste product, have you started to look into how to minimize full-lifecycle energy usage? (Plus water, nitrogen, agricultural crowding-out, etc.) And are you trying to scale up to a centralized production model, or focusing on on-site hydrogen production with logistics from the farms?
throwaway5752 8y ago
Thanks for the reply - it's a very cool and clever idea. I can't emphasize how much I hope you succeed.
strainer 8y ago
"In North America alone we have 32,000 gigatons of geological sequestration storage capacity" I suspect that is a tendentious estimate, considering no indicative amount of CO2 has yet been geologically sequestered and observed for effects. The wikipedia article has a graphic with CO2 being pumped into a "deep aquifer".
- semi-extrinsic 8y ago
  Well, we've had the Sleipner CO2 injection in the North Sea going since 1996 at close to 1 million tons per year, with extremely close monitoring including 4D seismic. There's hundreds of scholarly articles out there with field data and modelling of that case. I think we have some pretty good estimates of how it works by now.
  - strainer 8y ago
    Thankyou, then that is one useful test project. I hold doubts towards what seems to be mostly oil company sponsored research. It is one thing to have estimates for massive geological capacity for CO2 storage, a different thing to claim that capacity exists and that an environmentally sound industry could be developed to fill those, seismically sensed, deep subterranean environments.

by pkrein 8y ago

hanniabu 8y ago

What's the flow rate you guys want to achieve and what's the allowable variance?

pkrein 8y ago
Flow rate of biomass or hydrogen? Per unit we expect roughly 10-20 tons per day of biomass, and 0.5-1 ton per day of hydrogen. Allowable variance is low, but depends on the customer.
- hanniabu 8y ago
  Was referring to the biomass. So at 10-20 tons per day, I'm guessing you go through a hopper worth roughly every 10-15min?
  - chimere 8y ago
    10-20 tons per day is commercial scale. The prototype in this article was much smaller - running around 0.3 t/day.

chimere 8y ago

Also the USGS has this super cool map of potential CO2 storage in (under) the US: https://co2public.er.usgs.gov/viewer/ https://co2public.er.usgs.gov/viewer/

HillRat 8y ago

Fascinating stuff. If you’re using BECs rather than waste product, have you started to look into how to minimize full-lifecycle energy usage? (Plus water, nitrogen, agricultural crowding-out, etc.) And are you trying to scale up to a centralized production model, or focusing on on-site hydrogen production with logistics from the farms?

throwaway5752 8y ago

Thanks for the reply - it's a very cool and clever idea. I can't emphasize how much I hope you succeed.

strainer 8y ago

"In North America alone we have 32,000 gigatons of geological sequestration storage capacity" I suspect that is a tendentious estimate, considering no indicative amount of CO2 has yet been geologically sequestered and observed for effects. The wikipedia article has a graphic with CO2 being pumped into a "deep aquifer".

semi-extrinsic 8y ago
Well, we've had the Sleipner CO2 injection in the North Sea going since 1996 at close to 1 million tons per year, with extremely close monitoring including 4D seismic. There's hundreds of scholarly articles out there with field data and modelling of that case. I think we have some pretty good estimates of how it works by now.
- strainer 8y ago
  Thankyou, then that is one useful test project. I hold doubts towards what seems to be mostly oil company sponsored research. It is one thing to have estimates for massive geological capacity for CO2 storage, a different thing to claim that capacity exists and that an environmentally sound industry could be developed to fill those, seismically sensed, deep subterranean environments.