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#### JRP3

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Could that be a reserve capacity rating?

#### roflwaffle

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Well if you cannot afford to pay for the panels, you cannot afford to replace batteries every 3 to 5 years either. Off grid solar will cost you 10 times more than buying the power. And if in Canada, even higher.
Deja Vu! If by 10 times you means ~1+ times to ~7 times the price, sure?

#### roflwaffle

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I found non ( no ul cert)grid tie pannels thin film , for \$.99/watt 1400 watts will get 10,000 miles/year with out losses. used forklift batteries , big ups batteries used , used ups sine wave inverter 3to 5kw \$200 , new charge controller \$500 (Outback). 1400 watts/hr.X5.9 hours / day avarge (north cal ) X 280 days per year = 2,312,800 watt hrs. / year ( 2.3 mega watts/year)
*cough* mWh/year *cough*

#### aeroscott

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I have serious doubts about that. FLA batteries energy density are around 30 to 50 wh/kg. So how much does each battery weigh? 32 volt @ 650 AH they would have to weigh at least 420 Kg or 920 pounds each @ at the extreme high end of energy density of 50 wh/kg.

I believe you said they weigh 325 pounds each or 147 Kg. If they are 32 volt @ 650 AH would be a density of 140 wh/kg. So you are telling us a FLA has a higher energy density than LFP of 100 wh/kg? I seriously doubt that.

I am familiar with RR 32 volt batteries and Rolls Surrette makes a 32 volt 660 AH battery but it weighs in at 1240 pounds or 37 wh/kg. You must be seriously mistaken with either the weight or AH capacity
how many cells / battery ? 6 cells= 12 volts I have a old forklift battery 2000+ lbs , 24 volts , 2000 amp hr. 48kwh if new ( or .048 mega watts LOL)

#### aeroscott

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*cough* mWh/year *cough*
haven't worked with megs before : 1,000,000 watts = 1 mega watt . 20 times better batteries and we will be carrying megs in our cars and my diesel pickup carries about .9 mega watt hr. of output . 80 gallons x 15 hp/ gallon (net ) or 2.7 megs gross .

#### Ferroequinologist

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I could very well be wrong on weight and Ah. I was looking at the label through a vent hole in the battery box (haven't pulled any out yet) and I saw 650, next to a Ah.I suppose they may weigh 650, and have some different Ah. I will pull one tonight and get some really good pictures and such.

#### roflwaffle

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haven't worked with megs before : 1,000,000 watts = 1 mega watt . 20 times better batteries and we will be carrying megs in our cars and my diesel pickup carries about .9 mega watt hr. of output . 80 gallons x 15 hp/ gallon (net ) or 2.7 megs gross .
I'm just teasing. You dropped hours in the last part of your post for some reason.
2,312,800 watt hrs. / year ( 2.3 mega watts/year)

#### Sunking

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I could very well be wrong on weight and Ah.
I was not trying to be hard on you, at least not too hard But something just did not add up. The absolute best energy density by weight for lead acid batteries is around 50 wh/kg and that is for AGM types not FLA. FLA is more like 35 to 40 wh/kg. That is one of the reasons why they suk for EV applications. At 325 pounds for a 32 volt battery I would expect something on the order of 130 to 160 AH at best. It is just not possible to have a density of 140 wh/kg with any lead acid battery. Heck it is a stretch for any lithium to have that high of a density except for like Cobalt.

Honestly I give you the benefit of a doubt because I know they make 32 volt RR batteries in that high AH rating and even higher. But the one I linked to made by Surrette is 660 AH @ the 20 hour discharge rate and that thing weighs 1240 pound wet. So I hope you understand why I brought it to you attention

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