Endogenous fuel choice in shippingbetween Fischer-Tropsch, fossil oil, methanol, ammonia, LH2

[fneum]

Implement endogenous fuel choice in shipping between Fischer-Tropsch, fossil oil, methanol, ammonia, LH2.

Given little representation spatial distribution of shipping demand (currently population-weighted):

• Option A: research all the ports and distribute country-level loads according to material turnover
• Option B: implement shipping demands as "copperplate" (i.e. single bus with demands and links to fuel sources)

[euronion]

Option A: research all the ports and distribute country-level loads according to material turnover

I'm not certain, but not all ports might be ports used for bunkering. (Price differences, existing infrastructure, ...) Should be investigated before choosing this approach.

[fneum]

Spatial distribution for H2 (the only regionalised carrier) fixed in https://github.com/PyPSA/pypsa-eur-sec/pull/278