I'm wondering if anyone can respond to these questions: I could be missing this, but how long is it estimated to take for the devices to capture each ton of CO2? If the systems were installed to capture coal plant emissions, I'd imagine that the capture rate would be maximized. However installing the systems outside of those sources might lower the capture rate to the point that the system becomes impractical (i.e. like installing a wind farm in a location that's simply not windy enough on average)
- The cost estimate of $100/ton of CO2 includes only the operational cost of electricity. Is there some kind of a rough estimate for device production cost, system infrastructure cost and operational costs besides electricity (replacing absorbent etc)? On Lockheed rocket programs, we always included these to compare options more fairly. I realize that the report states: "Lacking a demonstration of an optimized system at scale precludes a precise estimation of costs and revenues", but maybe enough is known to make a rough cut now. FYI, on the Space Shuttle program the initial estimate for delivering payloads to orbit was $100/lb. That was a key decision point to justify the program, but in reality the cost ended up being about $1,000/lb. So even the best and brightest were too optimistic or overly simplistic in their approach (i.e. it's very easy to do). A rule of thumb we used on Lockheed rocket programs was to estimate costs in as much detail as possible for both production and operational costs, then we would multiply that by 1.5 times. This was surprisingly accurate when projects were all said and done.. Maybe a factor like this could be used for geoengineering estimates to make them more realistic. Best Regards- Mark Massmann On Saturday, June 1, 2013 11:33:56 AM UTC-7, Greg Rau wrote: > > Our latest offering on abiotic CDR can be found here: > http://www.pnas.org/content/early/2013/05/30/1222358110.full.pdf > > Some highlights: > air CO2 captured and safely stored - check > carbon-negative H2 produced - check > ocean alkalinity beneficially increased, OA and impacts reduced - check > <$100/tonne CO2 mitigated, about the cost of CCS - check > OK, more research is needed to better evaluate all of this. While trying > to locate the funds to do this, perhaps the APS would like to reconvene its > crack, air capture evaluation team and have a go. In any case, constructive > comments and criticism invited. > > Another point we make is that reducing air CO2 need not involve air > capture. By adding hydroxide to regions of the ocean that naturally degas > to the atmosphere (e.g. upwelling systems), excess ocean CO2 is consumed > and the natural ocean CO2 flux to the atmosphere (>300 GT/yr) is reduced > along with the air CO2 burden, sidestepping the need for more difficult air > capture. Air scrubbing is not necessary; cost effective and safe ways of > producing and applying (geo)chemical base to CO2-degassing regions of the > ocean would seem an easier alternative, especially considering that > effective air capture ultimately also requires effective ocean CO2 removal > (Cao and Caldeira). Bio approaches that could reduce CO2 flux to air > include OIF, biochar, and CROPS, but while likely cheaper, these don't also > generate ocean alkalinity and supergreen H2. Other ideas? > > Greg > -- You received this message because you are subscribed to the Google Groups "geoengineering" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/geoengineering?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
