Adding a second house battery bank
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ranger58sb
Guru
????
Would have thought T-105s would be reasonably affordable, and Sam's or Costcos or whatever even less expensive...
How far are you from the border? Road trip?
-Chris
OP
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Lou_tribal
Guru
T105 are around 235$ plus taxes.
For 190$ I can have Similar one shop branded, either princess auto or canadian tire.
I am living 1h from the vermont border this may be another option depending on price, xchange rate and hassle to go there and through customs.
L
Lou:
Ok batteries are expensive in your neck of the woods. But how about the cost of wire, switches, fuses, a combiner or ACR to install a second bank? That has to be more than $500 at your prices.
And I suggested replacing the Group 31s to get a bit more amp hours, have a real deep cycle battery and avoid mixing battery types with the GCs. If the G31s are FLAs you don't absolutely need to do that.
David
Ok batteries are expensive in your neck of the woods. But how about the cost of wire, switches, fuses, a combiner or ACR to install a second bank? That has to be more than $500 at your prices.
And I suggested replacing the Group 31s to get a bit more amp hours, have a real deep cycle battery and avoid mixing battery types with the GCs. If the G31s are FLAs you don't absolutely need to do that.
David
Lou
Did you identify the fridge that is causing all of this discussion? If you did, it has become lost in the discussion, but the fridge is at the heart of the problem. If you are not running a DC only, Dan Foss style fridge, you have far more load on your house bank than you should. That should be corrected immediately.
Then you can address the issues of bank capacity and charging capacity.
If you get your fridge draw under control by changing to the DC only Dan Foss fridge, you will need only 4 GC size deep cycle Lead Acid batteries for all of your house needs. those will be adequately charged, if on the hook, by one hour of genset time every morning and possibly another hour of genset at dinner time. You will want hot water at both of those times, so will be able to maximize the load on your genset while running it for charging.
You should also have a smart 3 stage regulator to take the shore, genset or alternator supplied charging power and feed it judiciously to your new house bank.
You won't need to do all of these necessary changes at once. the order is this:
1 Fridge to Dan Foss DC only
2 Inverter charger of 100 amp capacity with three stage, smart output
3 4 GC sized, Deep cycle LA batteries
4 100 amp alternator with 3 stage, smart output.
Don't try to mix in your existing 2 gp 31 batteries. If you can't bear throwing them out, use them up first, then switch to a new house bank of 4 GC size.
Did I mention the Fridge? Do it now. Don't put up with the power hog that drives you nuts for a moment longer.
Did you identify the fridge that is causing all of this discussion? If you did, it has become lost in the discussion, but the fridge is at the heart of the problem. If you are not running a DC only, Dan Foss style fridge, you have far more load on your house bank than you should. That should be corrected immediately.
Then you can address the issues of bank capacity and charging capacity.
If you get your fridge draw under control by changing to the DC only Dan Foss fridge, you will need only 4 GC size deep cycle Lead Acid batteries for all of your house needs. those will be adequately charged, if on the hook, by one hour of genset time every morning and possibly another hour of genset at dinner time. You will want hot water at both of those times, so will be able to maximize the load on your genset while running it for charging.
You should also have a smart 3 stage regulator to take the shore, genset or alternator supplied charging power and feed it judiciously to your new house bank.
You won't need to do all of these necessary changes at once. the order is this:
1 Fridge to Dan Foss DC only
2 Inverter charger of 100 amp capacity with three stage, smart output
3 4 GC sized, Deep cycle LA batteries
4 100 amp alternator with 3 stage, smart output.
Don't try to mix in your existing 2 gp 31 batteries. If you can't bear throwing them out, use them up first, then switch to a new house bank of 4 GC size.
Did I mention the Fridge? Do it now. Don't put up with the power hog that drives you nuts for a moment longer.
OP
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Lou_tribal
Guru
My fridge is a 110/12V. While working fine it is a bit old. Not sure of the power draw yet. Use it in 12vv at the anchor and 110 at the marina.
I won't need an inverter as almost everything is 12v aboard. I modified all lights with 12v bulbs. The only 110V appliance would the coffee grinder
(water heater is 110v but engine produce water hot enough).
I plan to add solar but not next year. I want to build a roof above my aft deck that will integrate the panels but will be done later.
Looking at gc2 price in US (82USD each at Sam's, thank you Mr John61), I may look at discarding the group 31 and replace this by 8 gc2. One question though, any issue with installing 4 gc2 on each side of the engine? This would equilibrate the charge but will require 6 to 8 feet wires to combine them.
L
I won't need an inverter as almost everything is 12v aboard. I modified all lights with 12v bulbs. The only 110V appliance would the coffee grinder
(water heater is 110v but engine produce water hot enough).I plan to add solar but not next year. I want to build a roof above my aft deck that will integrate the panels but will be done later.
Looking at gc2 price in US (82USD each at Sam's, thank you Mr John61), I may look at discarding the group 31 and replace this by 8 gc2. One question though, any issue with installing 4 gc2 on each side of the engine? This would equilibrate the charge but will require 6 to 8 feet wires to combine them.
L
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Great point! When I replaced my dead Norcold (3.1 cu ft) with a same footprint NovaKool (5.8 cu ft), I gained 87% capacity and save about 40% power. I am considering adding this gizmo to save even more energy and allow the NovaKool automatically defrost.
Fridge Optimizer | Stainless Lobster | Creative Marine Products
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Lou_tribal
Guru
Not sure about my fridge model but looks like your old one with false wood door and I estimate its capacity to something around 3cu.
It is in plans to replace it but available space is very limited due to hull shape that limit rear extend at the bottom of the fridge.
L
Some are concerned with multiple batteries being connected where there is a longer run to some batteries than others. But as long as the wire is big enough (sized for the inverter input if you have one otherwise connect the two with 1/0) then I wouldn't worry about separating one group of GCs from another by 8'.
David
David
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Lou_tribal
Guru
Going to over four times a bigger bank?
Better to keep it all together, each wire same size and length if possible, not like that's a little sailboat?
See "remote pair" diagram here http://www.familymotorsports.com/selfhelp/batterywiringdiagram/batterywiringdiagram.htm
Better to keep it all together, each wire same size and length if possible, not like that's a little sailboat?
See "remote pair" diagram here http://www.familymotorsports.com/selfhelp/batterywiringdiagram/batterywiringdiagram.htm
FF
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"I still have to find out what the current alternator is capable of, not sure of its amperage rating but it is working fine for the current setup."
The Brain , the voltage regulator , will not charge rapidly if it is the std auto / truck unit.
If the stock alt is powerful enough , and has a built in V reg (called a one wire system) remove the alt and have a shop rewire it for an external V regulator .
Then install a 3-4 stage V regulator.
Frequently simply installing a bigger 120v charger with an under 10KW noisemaker does little to improve the charge rate.
Just as a chop chop (square wave) inverter is weak at heavy loads , the small noisemakers also have reduced output in terms of the energy in their output .
The Brain , the voltage regulator , will not charge rapidly if it is the std auto / truck unit.
If the stock alt is powerful enough , and has a built in V reg (called a one wire system) remove the alt and have a shop rewire it for an external V regulator .
Then install a 3-4 stage V regulator.
Frequently simply installing a bigger 120v charger with an under 10KW noisemaker does little to improve the charge rate.
Just as a chop chop (square wave) inverter is weak at heavy loads , the small noisemakers also have reduced output in terms of the energy in their output .
ranger58sb
Guru
A small comment about the word "only." Some AC/DC fridges always run on a Danfoss DC compressor. Apparently (from reading in CF) that compressor actually takes DC but then runs on 3-phase alternating current (I'm unclear what that is). When fed household AC, a converter feeds DC to the compressor... which in turn still runs on 3-phase alternating current.
Without regard to the 3-phase factoid, our (NovaKool) fridges are like that: DC runs them, AC when available gets converted to DC first, and DC runs them. Lou's fridge may be the same.
I'd guess there some "ineffeciency" introduced by the AC-to-DC conversion, but often that'd be while at the dock on running on the genset... not necessarily a big deal. Running on an inverter would be less efficient, but that's when running on the DC setting in the first place removes the invert-and-convert inefficiencies.
As I understand it, ideally all the jumpers should be the same length (and gauge, etc.). Given a choice between one large bank of 6 co-located GC2s and an even larger 8-battery bank of two separately located sets of 4 GC2s... think I'd call it victory at 6x.
Maybe even at 4x, given you've said your anchoring periods aren't particularly long. And you did mention the option to run the genset, so recharging mid-stream apparently isn't out of the question.
In this latter case, though, you could also look at 4x L16s -- even more capacity in the same horizontal footprint -- if you've got overhead clearance, though I don't suppose the prices are as attractive. Still, if you've got overhead clearance, 4x L16s would likely cost less than 6x or 8x GC2s anyway. (Maybe.)
-Chris
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Lou_tribal
Guru
Thank you Chris.
While running our little generator is not an issue I would prefer not to do so if I have the choice. Nothing is more annoying than having the noise of it in a peaceful bay
Only negative aspect of L16 would be the weight, I don't see myself lowering these beast in my engine compartiment without a crane.
L
ranger58sb
Guru
Heh... we had do do something like that, even with the GC2s we installed recently.
We opened an engine room hatch in the saloon, to give us overhead access to the battery box area... and I tied a rope onto each battery, one at a time.
Then wifey stood up above and lifted with the rope while I also lifted down in the engine room, up and into the target battery box. Ended up being surprisingly easier than I had been expecting.
-Chris
Measure the fridge power draw. Then you can confirm the amount of power you need when away from the dock. Without measuring, you are only guessing, which can be a very bad thing, especially with Norcold fridges. My old Norcold AC/DC actually ran on AC all of the time. When away from AC, it had its own inverters, yes there were two of them, wasting power as they inverted the available DC into AC, pulling over 10 amps from the batteries whenever the fridge was running. When I had a knowledgeable fridge guy (Freddy Freezer, at North Shore Refrigeration in North Vancouver) work on the fridge, he replaced teh guts of the old Norcold with a DC only, Dan Foss compressor that still only draws 2.7 amps, runs less of the time than the old ones ran, so saves more than 7 amps.
If you are really planning to put in 8 GC batteries, look at the cost of those, spend 1/2 of that money on modifying your fridge to DC only and you win several different ways.
FF
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"Some AC/DC fridges always run on a Danfoss DC compressor. Apparently (from reading in CF) that compressor actually takes DC but then runs on 3-phase alternating current (I'm unclear what that is)"
The reason for converting DC to pulsating current is so a specific tiny amount of current can be provided.
By using a computer the unit can be run as slow as can be done and still provide the amount of power to move the heat out of the box.
This is by far the most efficient use of power for refrigeration , tho its expensive in terms of complexity.
The computer times how long it ran to satisfy the cooling requirement and will slow the unit to get to optimum performance.
Optimum would have the fridge working 100% of the time at the lowest speed , but the mfg get complaints from folks , "it never shuts off" , so optimum run time is about 50 min per hour.
Optimun rotor speed is similar to the inverter compressor units in modern split system air cond, Mitsubhisy , Panasonic etc.
The reason for converting DC to pulsating current is so a specific tiny amount of current can be provided.
By using a computer the unit can be run as slow as can be done and still provide the amount of power to move the heat out of the box.
This is by far the most efficient use of power for refrigeration , tho its expensive in terms of complexity.
The computer times how long it ran to satisfy the cooling requirement and will slow the unit to get to optimum performance.
Optimum would have the fridge working 100% of the time at the lowest speed , but the mfg get complaints from folks , "it never shuts off" , so optimum run time is about 50 min per hour.
Optimun rotor speed is similar to the inverter compressor units in modern split system air cond, Mitsubhisy , Panasonic etc.
ranger58sb
Guru
While running our little generator is not an issue I would prefer not to do so if I have the choice. Nothing is more annoying than having the noise of it in a peaceful bay
Fair enough, I do get that.
Can't "amortize" noise, of course... but doing a cost comparison of 2x or 4x more GC2s versus a couple bucks$$$ worth of diesel occasionally... might find it'd take a long while to amortize that...
-Chris
BruceK
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Lou, I may have forgotten, but do you have any solar panels?
Even a modest array like mine will keep the fridge and batteries fed during daylight hours(weather permitting),leaving the batts with only the overnight duty.
Some solar can reduce both battery bank size and the need to run the genset.
Even a modest array like mine will keep the fridge and batteries fed during daylight hours(weather permitting),leaving the batts with only the overnight duty.
Some solar can reduce both battery bank size and the need to run the genset.
OP
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Lou_tribal
Guru
Bruce no I don't have any yet.
I plan to build a roof over my aft deck with the solar panels but this will not be next spring as I have some other things to tackle or finish (better not to start everything at once
).But I definitively plan to add a bunch. More energy independent I will be happier I will be
L
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Lou, I think you and I are in the same boat, so to speak. I also wanted greater capacity and independence. After my mods, I was able to go 2 weeks on one fridge without a plug-in, pump-out or reprovision of food and beer. (I did dump trash at the area marina, but could have stored it aboard with little impact.)
CMS recently posted on a thread with his description of the perfect rec trawler electrical configuration. IMO, this post is one of the best posts on a great thread discussing the issue. It's far better to read the expert's words than listen to the rest of us yahoos .
CMS recently posted on a thread with his description of the perfect rec trawler electrical configuration. IMO, this post is one of the best posts on a great thread discussing the issue. It's far better to read the expert's words than listen to the rest of us yahoos .
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Lou_tribal
Guru
Thank you very much to point me to that thread!
If you are able to 2 weeks on one fridge you are my guru lol
I have been always energy conservative. I tossed the microwave as never using it, replaced all lights with led, got no gadget (or almost none) and installed propane as I love to cook and hate to cook on electric.
The last item to tackle is refrigeration which is my hungry man.
Still lot to learn and lot to do!
L
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I should add that I did run my Honda eu2000i a couple of hrs per day on average when I wasn't relocating the boat. Any boat run usually lasts 1.5 hrs minimum so my alternator provides the needed electrons and the engine heats the water.Thank you very much to point me to that thread!
If you are able to 2 weeks on one fridge you are my guru lol
I have been always energy conservative. I tossed the microwave as never using it, replaced all lights with led, got no gadget (or almost none) and installed propane as I love to cook and hate to cook on electric.
The last item to tackle is refrigeration which is my hungry man.
Still lot to learn and lot to do!
L
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OldDan1943
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Thank you Chris.
While running our little generator is not an issue I would prefer not to do so if I have the choice. Nothing is more annoying than having the noise of it in a peaceful bay
Only negative aspect of L16 would be the weight, I don't see myself lowering these beast in my engine compartiment without a crane.
L
Tossed the microwave? How do you reheat the coffee?
OP
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Lou_tribal
Guru
Argh never reheat a coffee, drink it hot, drink it cold but never reheat!
And to make it I am using an old style pressure coffee maker on the propane cooktop.
L
FF
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"Argh never reheat a coffee, drink it hot, drink it cold but never reheat!"
The best coffee is always reheated!
The great commercial coffee makers pass the brew water thru the grounds at about 160F in order not to pull acid from the grounds.
The coffee pot is then placed on a heating pad to bring the temp of the brew up to hot as folks expect.
Look in a resturiant at how they create great coffee.
The best coffee is always reheated!
The great commercial coffee makers pass the brew water thru the grounds at about 160F in order not to pull acid from the grounds.
The coffee pot is then placed on a heating pad to bring the temp of the brew up to hot as folks expect.
Look in a resturiant at how they create great coffee.
BruceK
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FF, you are a great authority on many things but imo, not on coffee. That muck stewing in a glass jug on a heating pad is undrinkable.
Stay with pressure coffee maker Lou. Bialetti type espresso maker?
Stay with pressure coffee maker Lou. Bialetti type espresso maker?
OP
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Lou_tribal
Guru
Yup Bialetti type, in France we called these Italian coffee maker. No electricity needed and descent coffee. Nothing to compare with a real expresso but good enough. I have a spare saeco expresso machine on my desk at work that I barely use, if I increase my power capacity I may add a small inverter to run it, it would be perfect but energy hungry I guess, need to check needed power.
L
OP
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Lou_tribal
Guru
On a side note, I recently replaced my anchor light bulb with a LED one, cheap version at 2.5$ a pair and the result is just amazing. The light is brighter than the old incandescent and use 15x less energy.
L
L
