genny then solar.....

[conachair]

Assuming it's a gray day with no wind which do you prefer for charging, a stint with the generator. (Honda eu1 into 20A mains charger in my case) then solar to try and finish off, or solar then genny? I'm tending towards genny first otherwise it can run for ages when the batts are getting towards full putting hardly anything in.

Thoughts?

Also, I'm thinking about splitting the main bank into 2 ( 4 x 6v t-105s) with the solar/wind switchable so that each half can get a proper days charge once in a while with nothing else running off them, I think it must be a rare occurrence for a cruising boats batteries to actually get fully charged.

Thoughts on that one?

Tia

[Kettlewell]

I usually do a generator or alternator run in the morning and/or the evening when the solar is the least and let the solar take over when the sun is highest in the sky. Sometimes you can time the generator charging to coincide with maximum power use--like running the inverter for some reason.

[rebel heart]

I really like my electrical system these days. It's stupid easy, safe, provides all the power we need, and is flexible.

- Keep your bank together aside from a starter battery.
- Wire all of your charging sources to the 12v positive house bus (solar, wind, panels, AC charger, etc).
- Use a Blue Sea ACR to keep the starter battery charged.

Just be flexible. If we motor somewhere for half a day our batteries are topped up. If we (like normal around here) have 12 hours of pure sunshine we're topped up. Night time winds blow 15 knots for 10-16 hours a day so wind generators provide decent output.

Kettlewell is right on about using the generator when you're hitting up the inverter. If you're going to watch a movie, use tools, or otherwise suck down a bunch of juice, put the generator on.

It's hard to come up with a plan in advance though. Ever locale is unique. Some places are overcast until the afternoon, some places are overcast after the morning, some places you get shadows, etc, etc. Just have a bunch of options, keep the banks simple and adjustment-free, and do your thing.

[cfarrar]

Depends, but typically first thing in the morning (neighbors permitting) so the batts accept the highest rate of charge. Shut down the engine or generator once the charge rate drops below X. Let the solar take over. Splitting the banks will result in deeper discharges, so I wouldn't bother.

[conachair]

Originally Posted by cfarrar

Splitting the banks will result in deeper discharges, so I wouldn't bother.

But do you batteries ever get fully charged? I thought I was doing OK until taking SG readings more regularly, takes a looooooong time to get to near full charge. I'm. Not thinking of doing it every day, but occasionally the batts might like it. Easier to equalize as well.

[rebel heart]

Originally Posted by conachair

But do you batteries ever get fully charged? I thought I was doing OK until taking SG readings more regularly, takes a looooooong time to get to near full charge. I'm. Not thinking of doing it every day, but occasionally the batts might like it. Easier to equalize as well.

To me that's more an issue of charging amps. We get to > 14.0v under some small loads every day, otherwise I get a little nervous. But that's two 135 watt panels in the Baja sun. So 250AH a day on our 500AH total capacity bank is completely reasonable.

I've seen people who abuse the hell out of their batteries, draining them low constantly and treating them like hell. We have ~3 year old T105's and they hold charge about as well as they did when they were brand new.

[conachair]

Originally Posted by rebel heart

So 250AH a day on our 500AH total capacity bank is completely reasonable.

Well you're all right then do you Sell to the local grid

[cfarrar]

But do you batteries ever get fully charged?

Yes, on a sunny day at anchor. If cloudy or underway then maybe not. We've got 215W of solar.

[Zil]

You need a Tesla Tower to transmit excess power while you are underway.

[sailorboy1]

Originally Posted by conachair

Assuming it's a gray day with no wind which do you prefer for charging, a stint with the generator. (Honda eu1 into 20A mains charger in my case) then solar to try and finish off, or solar then genny? I'm tending towards genny first otherwise it can run for ages when the batts are getting towards full putting hardly anything in.

Thoughts?

I think that is reasonable. I think the goal would be to use the generator till the amps into the battery is down to what you expect the solar to be able to supply, then just use the solar. This is of course for days when you what to get fully charged.

But I would also not do it unless the batteries got down to less than 75% as the next day could be a lot different. My 290W panel put in 60AH/day avergae last week while it was overcast and rainy for 4 days and the batteries were still fully charged end of each day (boat out on a mooring with the frig on all week).