Solar Upgrade verse Running the Generator

[Exile]

Originally Posted by Kenomac

When I run the generator for 45 minutes or so on days my wife is here and we're not moving, is to heat hot water which apparently uses a ton of juice while the batteries are also being charged. Watermaker and cooking all at the same time.

It's actually pretty impressive what you [U]can[U] run just off your batts., particularly the induction cooktop. And when you're motoring I think you said you have a heat exchanger for the h/w? Does your boat have aircon?

[Exile]

Originally Posted by john61ct

Just check your volts are within spec for the starter. But I'd go FLA on that too unless AGM required.

I've used both FLA & AGM's for starter batts. so should be ok. But if I'm using FLA for the house bank I can't see much reason to spend the extra dough to buy an AGM start batt, esp. with my relay system.

T-105 is really "the standard", IMO best stick to that unless real need dictates otherwise.

Probably good advice, and they seem to be much more available. And 675ah seems plenty given that I don't have a purely 12v/alt. energy boat. So far I've seen 105's as low as $129 but have read where they've been had direct from distributors for as low as $95.

Along with the Duracell's you mentioned earlier, I'm reading good reviews about the Deka's sold at Costco, as well as Interstate brand (same as Deka?). Doesn't seem to be any need to go expensive with these particular types of batts. Who knows these days, maybe all 4 brands are made by the same mfg. and just branded differently.

[ranger58sb]

Originally Posted by Exile

For some reason I thought each one of my 8D boxes could hold more than 2 6v GC's as well, but apparently not according to the Lifeline & Trojan websites.

Lifeline 8D: L 20.76" W 10.89" H 8.64"

Trojan T-105: L 10.30" W 7.11" H 11.07"

That could be pretty close to 3x/box, I guess, depending on the actual box measurements. Presumably there's a small bit of space around the outsides of your 8Ds?

10.30" will fit within 10.89". 3x 7.11" will fit within 21.33" given some airspace in your box. If you have any.

Height can be an issue, of course...

-Chris

[john61ct]

Originally Posted by Exile

have read where they've been had direct from distributors for as low as $95.

Suspiciously low, check mfg date, warranty, thoroughly test before installing

Originally Posted by Exile

Along with the Duracell's you mentioned earlier, I'm reading good reviews about the Deka's sold at Costco

No, Deka is East Penn makes the Duracell GCs, best value if you think you can't coddle them.

Costco's aren't quite as good, those and most Interstate made by Johnson Controls (JCI).

But Trojan even better than Deka, if within 25% worth it IMO.

Their RE line is an even bigger step up for robust longevity.

Crown, Superior and U.S. Battery good makers too.

Rolls / Surrette at the top.

[sailorboy1]

I have Trojan t105 s now but had Deka/Penn private label before. They don't seem any different. The golf cart market is tough and I bet any brand is good or they wouldn't survive in the marketplace

[Exile]

Originally Posted by ranger42c

That could be pretty close to 3x/box, I guess, depending on the actual box measurements. Presumably there's a small bit of space around the outsides of your 8Ds?

10.30" will fit within 10.89". 3x 7.11" will fit within 21.33" given some airspace in your box. If you have any.

Height can be an issue, of course...

-Chris

Why didn't I think of that! Just turn 'em sideways. (Goes to how dangerous my little bit of knowledge really is.). Should work given the surrounding airspace but I'll confirm when I'm back on the boat in a couple of weeks. So 225ah x 4 = 900ah(!) plus a bit of extra space in the 3rd box for whatever. Might have to upgrade my alternators & batt. charger a bit, but 900ah could favor switching over to 12v refrig. Boy oh boy this thread could wind up costing me a lot of $$$ . . . .

[Kenomac]

Originally Posted by Exile

It's actually pretty impressive what you [U]can[U] run just off your batts., particularly the induction cooktop. And when you're motoring I think you said you have a heat exchanger for the h/w? Does your boat have aircon?

We have a/c which we haven't used in five years and yes we have a heat exchanger in the waterheater.

Can I offer up a bit of good advice that will probably save you a boatload of money and trouble?

[sailcrazy]

Based on advice that I was given, suggest you buy/install batteries for the purpose they were intended. For the house....use deep cycle batts. But for starting your engine/genset...use a starter battery, ie, a car battery. The battery construction is significanly different, and so is their purpose (multiple recharging at lower amps vs hi amp discharge over short duration). Our system is 6-T105s for the house, and a mx-free start battery to start the engine(55hp) or the genset. As I've written....it's worked flawlessly since installation in 2002.

[Exile]

Originally Posted by Kenomac

Can I offer up a bit of good advice that will probably save you a boatload of money and trouble?

Yes, of course/always! Lemme guess . . . if it's all been working fine all these years then add some solar to supplement and move along to the next system that needs attention. That's been my approach on the electrical & refrig the past 10 yrs., except w/o the solar. But then again just about everything else has broken so I've been busy.

Watchu got?

[john61ct]

Originally Posted by Exile

Might have to upgrade my alternators & batt. charger a bit, but 900ah could favor switching over to 12v refri:

You're already way past minimum for that, many do so with 200A.

Of course have to put back in every day what you take out, that's the real limit. A bigger bank just gives more leeway for poor solar days, may not need to run the genset every day.

Most efficient 12V fridges use around 25-40AH per day depending on insulation and temperatures.

[Exile]

Originally Posted by sailcrazy

Based on advice that I was given, suggest you buy/install batteries for the purpose they were intended. For the house....use deep cycle batts. But for starting your engine/genset...use a starter battery, ie, a car battery. The battery construction is significanly different, and so is their purpose (multiple recharging at lower amps vs hi amp discharge over short duration). Our system is 6-T105s for the house, and a mx-free start battery to start the engine(55hp) or the genset. As I've written....it's worked flawlessly since installation in 2002.

Can't remember if you said you're still on the same house batts. If so, that's 15 yrs. and remarkable. Do you equalize them every so often, or maybe stay plugged in a lot?

[Exile]

Originally Posted by john61ct

You're already way past minimum for that, many do so with 200A.

Of course have to put back in every day what you take out, that's the real limit. A bigger bank just gives more leeway for poor solar days, may not need to run the genset every day.

Most efficient 12V fridges use around 25-40AH per day depending on insulation and temperatures.

Big fridge and a very large separate freezer, but the insulation seems better than most boats of that era. Might require a larger than avg. 12v compressor pulling well above your estimate. Maine Sail had a similar (but probably smaller) 110v Seafrost on his boat & was able to get the factory to swap out the compressor to 12v. Not sure that will work with my 110v water-cooled (holding plate) system. Leaving my refrig the way it is means cranking up the genset well before I need to charge batts., and so there's not much to be gained from a larger capacity battery bank. It all has to fit together . . . .

[sailcrazy]

I wish it was still the original set of batts!!! No, we're on our 3rd set; these were new/installed in 2013. The T105s do well, and last a long time.....but not that long.

[Exile]

Originally Posted by sailcrazy

I wish it was still the original set of batts!!! No, we're on our 3rd set; these were new/installed in 2013. The T105s do well, and last a long time.....but not that long.

That sounds more like the avg. I've seen, namely 5 yrs. But YMMV of course.

[sailorboy1]

The cruisers I've met that don't really know anything about their batteries still seem to get 4-5 years out of 6V golf cart batteries. That works out to like $30/year more expensive and given that they don't experience the constant battery worry stress seems like a fantastic deal!!!