Newbie boat owner here. I have a boat with a 24v battery setup that comes with a charger with an ac electrical outlet, but nothing to plug into. Are there any viable solar options to charge my batteries without costing a fortune? We take the boat out once a week at most.. not sure if that’s even enough time to charge them on solar. Any advice would help!

It sounds like you boat has an onboard battery charger. If it is a male plug then that would plug into an AC outlet to charge your batteries.

you won't see any benefit in just a week, solar is meant more to maintain than to recharge.

not sure what you mean by electrical outlet, if it is a female then it is an inverter (bad idea on a bass boat), if male then probably your charger and just plugs into 120v.

if you can, pop breaker while charging, breaks the circuit so charging is safer. if you don't have one may want to upgrade to this style (in appropriate amperage).

I’d look into a Stealth Charger, it charges the TM batteries when the cranker gets fully charged or you might buy an inverter generator to charge the batteries as much as possible before & after use.

You haven't said if this is a fishing boat with one primary (starting) battery and one battery for an electric trolling motor, OR if you have a primary (starting) battery along with a secondary (backup) for that main battery. Depending on how you use the boat, and what options you have (such as radio/electronics) and how much "run time" you put on the outboard, you may or may not maintain the battery charge level. A trolling motor battery will need extensive charge time immediately after each trip to recharge it.

"Renewable" energy sources are not practical for charging boat batteries - a sufficient solar system would have a substantial cost and size.