Poll

 What source of power do you use for equalizing your lead acid batteries (ONLY during equalization)?

RE Only (no supplemental source)
8 (38.1%)
RE with grid assist (more than 50% of average current comes from RE)
2 (9.5%)
RE with fossil fuel driven generator assist (more than 50% RE)
2 (9.5%)
Fossil fuel driven generator only
1 (4.8%)
Fossil fuel driven generator with grid assist (more than 50% generator)
0 (0%)
Fossil fuel driven generator with RE assist (more than 50% generator)
2 (9.5%)
Grid only
1 (4.8%)
Grid with RE assist (more than 50% grid)
3 (14.3%)
Grid with fossil fuel driven generator assist (more than 50% grid)
0 (0%)
I don't use lead acid so I don't equalize
2 (9.5%)
I don't use batteries at all
0 (0%)
What's equalization?
0 (0%)

Total Members Voted: 21

Author Topic: Source for Equalization  (Read 4411 times)

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Madscientist267

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Source for Equalization
« on: May 02, 2011, 07:00:29 PM »
Equalization is very 'wasteful' in the sense that a lot of energy goes into the battery that doesn't get stored for later use.

Because so much extra energy is needed to complete the process, not every RE system is up to the task, and may require a supplemental source of power while the batteries are being equalized.

Where do you get this energy from when you equalize your bank?

Please only include energy for the purposes of equalization in your response.

RE includes anything that does not come from the grid or fossil fuels.

Alcohol (if you produce it yourself), woodgas, and biodiesel, as well as pedgen, hand crank, or even gerbil (if it works!) - all fall under RE.

If I've left something out, feel free to add on. ;)

Steve
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How much magic smoke it contains does !

DamonHD

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Re: Source for Equalization
« Reply #1 on: May 03, 2011, 07:04:10 AM »
I use gel SLAs, so don't equalise.  There's always gotta be one!

Rgds

Damon

Madscientist267

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Re: Source for Equalization
« Reply #2 on: May 07, 2011, 06:36:19 AM »
LOL yeah, many possibilities... It's hard to think of them all for a poll... I spent like a day trying to figure out exactly how I wanted to word it to get the best results.

On that same note, ATM, after 5 days, there's only 11 voters.

Surely, there are more than 11 FLA banks out there in use...  ;)

Steve
The size of the project matters not.
How much magic smoke it contains does !

dnix71

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Re: Source for Equalization
« Reply #3 on: May 07, 2011, 07:31:38 PM »
I just kept adding panels until I hit float every day except under really bad conditions. Then I added batteries to get me over the weak days.

Madscientist267

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Re: Source for Equalization
« Reply #4 on: May 08, 2011, 12:13:49 PM »
LOL I think that's the 'disease' part of all this hahaha

Since money is tight ATM, I have fallen into a nook of squeezing every nanowatt out of what I got.

I even went as far as to make a little mod to my (now) primary dump controller so that I'm wasting as little as possible.

I put a switch in it to select between the traditional dump load and an external 'dump gate' as I call it. Rather than just siphoning off the extra juice and getting rid of it as heat, I dump it into the 8D. My general direction over the past couple of weeks has been to use a smaller battery for primary storage so that full charges are more of a daily occurrence. A 220AH battery is a little bit much for just 60W of panel; 36AH is much better suited, not to mention fits into the 'portable' category a bit easier. :)

In the event the 8D does fill completely up, which does happen, a secondary dump controller gets rid of the surplus.

It has a minor drawback; as the 8D approaches 13.8V, and beyond, its ability to clamp gets less and less as the internal impedance rises. The result is that the 36AH set floats a little high (14.65V), even though the controller is set to 14.3V. This is down from 14.4 since summer is essentially here, and they are of the SLA variety (2x18AH).

Steve
The size of the project matters not.
How much magic smoke it contains does !

Ungrounded Lightning Rod

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Re: Source for Equalization
« Reply #5 on: May 08, 2011, 01:38:17 PM »
Equalization is very 'wasteful' in the sense that a lot of energy goes into the battery that doesn't get stored for later use.

With RE sources rather than fuel-driven generators you either have too little generation - and your batteries drain and die - or you have too much generation - and you must dump.  There is no middle ground where things match.

If you have too much generation you can use the surplus to equalize occasionally by moving the dump load setpoint up to the equalization voltage.

Madscientist267

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Re: Source for Equalization
« Reply #6 on: May 09, 2011, 11:06:52 AM »
That's the idea behind this poll; I can regularly charge the 8D, but the inefficiencies at equalization are more than 60W (45) of panel can overcome.

I'm not surprised at the results so far, although I would like to see some more cross section. I fall under the "grid with RE assist" category, since I have to sustain 4A to hold 15V. On the best of days, I may peak the occasional 4A, but can't hold it long enough for it to be useful for that purpose.

This whole 'dump to another battery' thing appears to work very well in my situation... I get a good full charge, just about regardless of weather (to a point), and yet the excess isn't 'wasted' nearly as much. As long as I am cautious with my usage from the 8D, I can maintain a good charge in it and not explicitly dump the surplus as heat. I'll go into better detail with my findings in my main diary entry after I've run it this way for a while. Might be of use for those with smaller systems. ;)

Steve
The size of the project matters not.
How much magic smoke it contains does !

madlabs

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Re: Source for Equalization
« Reply #7 on: June 04, 2011, 08:37:36 AM »
I use my lawnmower/alternator for EQ, simply because it is the only charging source I have complete control of the charge and can hit 15.5 and taper down the amps. My solar only has a relay for control, so I set it to turn off at 15.6 and then run the lawnmower. This way I get as much as I can from solar and taper the chrage nicely.