This
post by
@seaexplorer got me thinking about the benefits of vertically mounted bi-facial solar panels on Mars.

[Created by Grok on my prompts]
As shown above they would be hung from a simple rail in an East-West orientation.
As has
already been proven on Earth, vertically mounted bi-facial solar panels outperform perfectly sited and angled single sided panels.
Most importantly, hanging flexible bi-facial panels like washing from a line is very simple and easy to do and could be done by SpaceX Optimus robots.

[Created by Grok on my prompts]
Vertically mounted bi-facial panels have the following additional advantages on Mars:
- stay clean as dust falls off and is blown away by the light winds in the thin atmosphere - this is super important as cleaning is a huge labour & time cost in a labour constrained Mars settlement;
- are very lightweight with a much better power density than framed panels and actually far better than current nuclear tech - power density is key because tonnage to Mars is limited even with Starships
- stay cool (for better efficiency) because of excellent air-flow on both sides and because even in still conditions, warmer Mars air doesn't get trapped by the panel, it rises vertically along panel and escapes;
- production better matched to usage: they produce substantial power from the moment the sun rises and keep producing power until the sun sets, providing at least 4 hours per day of additional solar production, thus reducing the time that batteries need to cover loads - less expensive and heavy battery capacity is needed to cover night loads.
- they gain additional light from reflections from Mars surface further increasing electricity production.
While Mars is further from the sun and solar insolation is less than Earth, its atmosphere is very thin and it doesn't have substantial cloud cover so real world solar production should be similar to Earth.
It is possible that multiple Starships could land on Mars with Optimus robots in later 2026 so how to best deploy solar panels is a real & near term issue.