Comment by ihaveone
6 hours ago
It looks like they could have mounted at least 100 solar modules on top, if not 200. That's 600-1200kwDC, given its flat, at 800kwp/kWh, that means for an hour of peak production, after losses, would do at least 300kwh for the smaller size and 600kwh for the larger size. If each trip is around 1150kwh and takes longer than an hour, more than half of the power required could be generated. As solar modules are solid-state devices, seems short sighted to not slam a system on the roof. PV modules are literally just glass sandwiches with wires and DC to DC battery chargers are very efficient. The weight would also be partly counter-acted by using the modules as the skin for the roof.
Your math is far off. If you put 60kW (STC rating) of PV panels as quantity 100 of 600W premium panels on top, in Uruguay, it'll produce somewhere between 6800 to 8100 kWh per month if the panels are perfectly exposed to sun from sunrise to sunset.
If we say it's 7500kWh a month that's something like 250 kWh of production per day, which is a tiny drop in the bucket compared to the amount of energy needed to charge the ferry.