Question about solar panels and batteries.

[Scott T-Bird]

Because I'll be on a mooring at Santa Catalina Island (approximately 25 NM from Long beach), I'll likely purchase a boat without solar panels and can get a whole system of solar panels, new batteries, etc. Yes, I am planning to spend several days mooring (and might go around the island, it'll be fun).

Your question really relies upon what you find in your new boat. IF the alternator is functioning properly and IF the battery banks provide suitable capacity (typical for a 34' sailboat), a day sail to your new location is entirely feasible without relying upon solar charging. You should <probably> find a house bank consisting of a single battery or a pair of batteries with up to at least 100 to 200 aH capacity or more. But that also depends on the health of the batteries, which you should try to find out. You may also have an auxiliary (or start) battery that may or may not be deep cycle. On your trip, be sure to leave with a fully-charged auxiliary and only use it if necessary to start your engine. As a last resort, your alternator will keep all systems running in the unlikely event that your house bank runs out of juice.

Base your purchase decisions for solar power on your anticipated use (I doubt there will be any need to look for solar just to get the boat to your new destination - assuming that you buy a properly functioning boat).

 

[Tin Kicker]

It actually wouldn't take a lot of solar for what you describe and a quick temporary solution would be just 200-300w of (2 to 3) panels sitting on the deck. While our panels are permanent above the bimini, we run our lights and portable 35L fridge on 200w with no problem.

 

[Captain Larry-DH]

Your question really relies upon what you find in your new boat. IF the alternator is functioning properly and IF the battery banks provide suitable capacity (typical for a 34' sailboat), a day sail to your new location is entirely feasible without relying upon solar charging. You should <probably> find a house bank consisting of a single battery or a pair of batteries with up to at least 100 to 200 aH capacity or more. But that also depends on the health of the batteries, which you should try to find out. You may also have an auxiliary (or start) battery that may or may not be deep cycle. On your trip, be sure to leave with a fully-charged auxiliary and only use it if necessary to start your engine. As a last resort, your alternator will keep all systems running in the unlikely event that your house bank runs out of juice.

Base your purchase decisions for solar power on your anticipated use (I doubt there will be any need to look for solar just to get the boat to your new destination - assuming that you buy a properly functioning boat).

This is the best answer so far.
@madmax asked what it will take to quench his thirst and we turned on the fire hose. We can’t expect him to digest this much info at this stage.
MadMax please ask this question again when you know the details of the boat you are buying. We will ask what electrical loads there will be to satisfy “thirst” (instruments, fridge, radar etc), what battery types and rated capacity, and whether they are separated into two banks (engine start and “house”). It will also be important to consider engine regeneration, so we will ask about engine alternator power. Then we can get specific about things. Good luck boat hunting, and welcome to SBO.

 

[madmax]

This is the best answer so far.
@madmax asked what it will take to quench his thirst and we turned on the fire hose. We can’t expect him to digest this much info at this stage.
MadMax please ask this question again when you know the details of the boat you are buying. We will ask what electrical loads there will be to satisfy “thirst” (instruments, fridge, radar etc), what battery types and rated capacity, and whether they are separated into two banks (engine start and “house”). It will also be important to consider engine regeneration, so we will ask about engine alternator power. Then we can get specific about things. Good luck boat hunting, and welcome to SBO.

Yes I will ask this question again when buying a boat. I'll tell you what the boat has (battery, instruments, fridge, etc). I should be back with new questions in Spring 2025 (that's when I am hoping to get a boat). Thanks so much.

 

[Indysailor]

Lots of unknowns here, like the wattage of the solar panels, how they are are hooked up to the onboard electrical system, what kind of charge controller, etc. I don't know, maybe just buy a couple basic group 27 deep cycle batteries and bring them with you. Use what is on on board knowing you have backup power to install if needed. One thing I know, never trust a used battery or outboard engine that you don't have experience with.