New Small Boat Battery(s) & Alternator Questions

[Colin A]

Wow that is a compact mooring field amazing the amount of boats in there. I think Solar is a good idea in your case. Most people underestimate the time they spend getting on and off a mooring to go sailing but in your case you can't get much closer to open water. Because of this I think your engine will have limited time to charge your battery even if your only using it very little.

[skipmac]

I will also vote for solar. Even if the panel is shaded for a lot of the day, it will still be charging at least part of the time and might add more amps than you think.

Also, you might want to look more closely at your energy usage. A small sound system will not draw a huge amount but if you put in even a moderate sized system and crank it up it will suck down amps. Lights can draw a lot as well unless you have LEDs. Don't forget the anchor light burning all night.

[sparrowhawk1]

I'm a solar fan too. but I'm surprised no one else pointed out that running your diesel for 5 minutes at a time is very bad for it. the condensation will age it out faster than if it just sat. I have enough solar so I almost never have to use my engine for charging but if I do I let it run for at least an hour and rev it up to blow out carbon before I shut it down. oh yeah and I keep it in reverse when I'm anchored. Put it in forward for a short burst and then put it back in Reverse for a short burst and then shut her down.

[Schrewsburyduo]

Flexible solar panel (long one) over sail cover. You can even sew the grommets on...
Group 24 flooded (Trojan or something like that) and starting battery (Interstate).

[Codybear]

The harbor is about as crowded as it gets. The swinging moorings all go bump in the night when the wind dies. I found an aerial with the boats in it. If you want to see a somewhat neat landmark in the earlier link, while at 45 degree view, just go S-SW of the harbor and it's what we call the giant orange squeezer.

The lights are led and will be rarely used. Any stereo will be very modest in amperage and connected via mp3 player so no loss from a CD player. And at most 1-2 flush with an electric toilet. That will be the typical usage.

Yes, I know it is going to be rough on the engine. Starting will be one of the first things to do after getting on the boat and I will have to keep it running a bit after the sails are up. About 50% of the time we sail to the slip, but I may have to run the engine, especially if the toilet was flushed. I'll certainly have to run it more than the current 22' boat with an outboard which probably only gets at most 1-2 hours a year. It will be interesting if I even put 10 hours on the engine in a year. In 20-30 years, just be weary about buying a C275 with only 200-300 hours. Looks like solar is really my best option or just have disposable batteries.

For the batteries, I may not be able to go with a Trojan because I think they are too high as the wing nuts are on top of the terminals. I really need to keep the house battery less than 9.5" in height including terminals, so this limits my selection. I'll probably just keep the Exide for now and replace in a couple of years. For the starter, I think I may be able to place an Interstate group 78 (7.375" height) with side posts under the rear bunk.

Hopefully, my link above doesn't cause this to go to the moderator again.

[Codybear]

120 amps it is. Smaller is not an available option on the C275. Over sized won't be a problem with a single FLA house battery.