Cruisers Forum

Join CruisersForum Today

Thread Tools Rate Thread Display Modes
Old 21-10-2010, 09:35   #1
Registered User

Join Date: Sep 2010
Location: florida
Posts: 153
Can You Ever Have Too Much Reserve Electrical Power ?

Can you ever have 2 many batteries or 2 much reserve capacity ?? My friend owns a golf cart shop and can get me as many 12v golf cart batts as I want ,rated 208 mins of reserve @ 25 amp draw for 25$ a piece. They are takeouts when they refurb carts. They all load test and hydro test out good so why not have 2000 minutes of capacity ??
I have 2 300 watt wind gens to keep them fed .....


chadlaroche is offline   Reply With Quote
Old 21-10-2010, 10:03   #2
Senior Cruiser
rebel heart's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Posts: 6,190
Images: 3
Except for the hassle of moving batteries around every few years to replace them and the weight I can't think of anything off the top of my head.

rebel heart is offline   Reply With Quote
Old 21-10-2010, 10:05   #3
Senior Cruiser
Vasco's Avatar

Cruisers Forum Supporter

Join Date: Apr 2004
Location: Toronto
Boat: CS36Merlin, "La Belle Aurore" Ben393 "Breathless"
Posts: 6,819
The size of your battery bank will be limited by your capacity to charge them. Don't rely totally on your two wind generators.
Rick I
Toronto in summer, Bahamas in winter.
Vasco is offline   Reply With Quote
Old 21-10-2010, 10:23   #4
Registered User
capn_billl's Avatar

Join Date: Aug 2010
Location: Houston,Tx
Boat: Maxum 37'
Posts: 1,587
Where is the shop? I would like a couple of extra. My experience with Batteries is this. Like the poster above you need to keep them charged and that means having charging capacity equal to usage. You have 50amps peak from the generators, and for continuos usage you'll want to be able to recharge bank in approx 1/5th time. Multiply load by time, I.E. you want to run the fridge and anchor light all night without running the generator. 5 amp fridge (run by inverter = 60amp DC/ duty cycle 30%)+ 1 amp lights = 21 amps time 10 hours = 210 amp hours * reserve 20% = 250AMP hours. Those are 80 amp hour batteries so 4 of them will power the example boat all night. a 100 amp charger will recharge them in approx 3-4 hours, your 2 * 25 amp windmills will need a stiff breeze all day. More batteries than that and you wont be able to keep them charged and they will fail.
capn_billl is offline   Reply With Quote
Old 21-10-2010, 10:46   #5
noelex 77's Avatar

Cruisers Forum Supporter

Join Date: Jul 2007
Location: Full time cruising. Currently in the Med.
Boat: Aluminium yacht
Posts: 10,013
With an offer of cheap batteries like that you would be mad not to take advantage of it.

Remember however batteries donít make electricity. You still need to put back what you take out.

The ideal battery bank size is governed a lot by you usage and access to a mains supply.
With the availability of cheap batteries it is sensible to oversize the capacity, but the laws of diminishing returns start to set in so yes you can have too many batteries, where the weight and space taken up outweighs the advantages
noelex 77 is offline   Reply With Quote
Old 21-10-2010, 11:15   #6
Registered User

Join Date: Sep 2010
Location: florida
Posts: 153
when I originally started this whole adventure I was trying to live without a fridge and use just a solar panel. just wanted to make sure i could make 3 days of cloud cover and still run lighting. Now its grown to double wind gens that I had hoped would cover my power needs.
Alas there is now a full time fridge , 2 tvs all kinds of electronic,computer chart plotters radar, wireless router ,fancy LED rope lighting( for the ladies ) inside besides reading lights , lights in the cockpit , 12v swimming pool light for night fishing etc,battery packs for tools,microwave ,crockpot ,rice steamer .And to think i originally was going to BBQ every night??
The boat came with a portable AC unit (the kind from Home Depot) which also dehumidifies. Not sure if its just too much power to run even with a small generator.Leave it or install it ?
I suppose I could add another alternator to the yanmar.... decisions decisions.Maybe I'll carry some extra to sell along the way .......
chadlaroche is offline   Reply With Quote
Old 21-10-2010, 16:06   #7
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 15,103
Our first house bank was 240 Ah,
we replaced this in NZ with a 170 Ah,
now I will go down to 110 Ah or so.

So, by half.

Meanwhile we also:

- doubled the solar bank (energy x 2),
- upgraded our alternator regulator (energy x 2),
- replaced nav lights with LEDs (energy/5),
- replaced laptops with netbooks (energy/2).

It is nice to have a lot of energy but the 'lot' is related to the consumption needs, not to an imaginary fixed number.


barnakiel is offline   Reply With Quote

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Increasing Electrical Power by Solar or Wind james ensor Electrical: Batteries, Generators & Solar 0 02-05-2010 03:11
Power Through Electrical Control Board FraidNot Electrical: Batteries, Generators & Solar 1 22-04-2010 05:43
Battery Capacity - Reserve kcmarcet Electrical: Batteries, Generators & Solar 11 20-10-2009 11:02
Rewiring a relic--power advice? Electrical gurus? Sinuous Electrical: Batteries, Generators & Solar 26 20-02-2009 20:54
??? about electrical consumption/battery power/solar/wind dustinp Electrical: Batteries, Generators & Solar 14 23-10-2007 19:54

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 16:30.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.