A path not taken in carbon offset (if not reduction)

[James Bowery]

I suppose I should include a link to the, now defunct, Diogenes Institute website's quasi-spreadsheet macroengineering model to offset all US elex CO2:

https://web.archive.org/web/20220524031001/http://diogenesinstitute.org/index.php?title=Fullspreadsheet

Although Diogenes founder, Charles Sinclair Smith, was going to meet with his college friend and then-Biden cabinet science secretary Eric Lander about this plan, I had to pull the plug on it because the approach produced far more food than the entire world could consume even assuming US levels of protein and even after passing through multiple trophic levels in agricultural feedstock.  

The plan depended on macroengineering scale to leverage industrial learning curve cost reductions and a nation-wide CO2 network approximated in this map with the green indicating a possibly international photosynthetic region to provide some jobs for residents of Mexico:

The scenario active at the time-stamped link I was preparing for Lander utilized off-peak generating capacity to produce NH3 that would be delivered in pipeline network parallel to the CO2.  This produced even more CO2 hence even more algal biomass which is why I had to recommend against.  This is also why I'm fairly confident that land-based agricultural CO2 emissions could be largely eliminated by ocean-based algae photobioreactors.

I should also mention that it took me a few years to find an algae cultivation technology that overcame the OPEX and CAPX problems dogging that approach for decades.  But I found it and it relied on saline flotation medium for the less dense growth medium.  The ocean provides this at the cost of wave barriers.  It also provides sufficient heat buffering to avoid the cost of deep land-based lagoons.  Finally, assuming the wave state is only moderated rather than eliminated it provides mixing action that otherwise must be provided by energy inputs (although the CAPEX of wave provision may still be necessary for time continuity of mixing).

[James Bowery]

One may notice from that site that the "spreadsheet" was actually a very complicated Wiki site, one page per "cell" to be computed or given as parameter.  To do that I had to modify the way the Mediawiki software handled recalculation of its encached web pages so I could edit and have the consequences flow through the resulting model.  

I'll make those mods available if others find working with normal spreadsheets difficult as their models increase in size -- which is what forced me to modify Mediawiki.