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Interesting stuff!

I recommend starting the batteries out at full. Otherwise it seems you always have curtailment early on... Seems more realistic (charged batteries don't weigh any more than empty ones).

Also, what about fuel cells that run on CH4? It would be interesting to model that. How much CH4 / batteries / solar do you need to kick-start a self-sustaining Sabatier-based colony? Could CH4 storage replace battery storage?

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Completely off-topic, but your assertion about the weight of charged batteries caught my attention. It would seem that E=mc^2 comes into play here. I believe charged batteries actually do weigh more than uncharged, though probably not by any measurable amount.

Depends on battery tech. Metal-air batteries, in which atmospheric oxygen (on Earth) is the cathode, weigh more when discharged.

https://en.wikipedia.org/wiki/Metal–air_electrochemical_cell

100 kWh are equivalent to 4e-9 kg.

Nice suggestion! I’m reading Zubrin’s Case for Mars at the moment, the different possibilities for chemical processes are really extensive. Will look into adding fuel cells.

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