This guy claims lead acid is superior to Lithium Iron Phosphate in solar applications

[rin67630]

I have Trojan Solar SPRE 06 255. Each has six volts with 255 amps at 100 hour rate. At the 20 hour rate that drops to 229 amps. I have four of these batteries, two in series two in parallel. This comes to 458 AH at 12 volts.

C/100 is just the right rate to run for 4 days off batteries.
With 458 AH at 12 volts and max 50% DOD you can feed... ~28W for 4 days!

If you have 1KW of panels, you may get on a heavy cloudy winter day 60 Ah additionally, so you could push your mean power consumption to a whoppy 33W! Youpeee!

 

[rin67630]

I think you and I are saying the same thing. I can charge my 458 AH of Trojan's at 59.4 Amps. This is not a fast rate.

On the data sheet they say: if charging time is limited, contact us...
You may charge faster for a couple of hours.

 

[HighTechLab]

I remember watching this guy's videos a long time ago when I blew up my first Xantrex 2000w Hi-Freq inverter and trying to learn a thing or two. I saw this video come across my subscription feed and only watched about a minute before realizing it's probably not worth my time. Felt more like a preaching video as compared to much of an educational one.

 

[rin67630]

I'll have to compare it to PVWatts from NREL.

PVWatt does not seem to provide anything to evaluate off grid systems, does it?

 

[hankcurt]

PVWatt does not seem to provide anything to evaluate off grid systems, does it?

Not to my knowledge.

It does incorporate weather data to help provide realistic daily production figures in the table it produces for a given PV array at a given location. I'm guessing that PVGIS does the same, so I am curious to see if they calculate similar production expectations.

 

[rin67630]

Not to my knowledge.

It does incorporate weather data to help provide realistic daily production figures in the table it produces for a given PV array at a given location. I'm guessing that PVGIS does the same, so I am curious to see if they calculate similar production expectations.

Take a look at it, does much more, provides extremely detailed results, and use powerful databases, down to integrating the influence of mountain's shadows. Anyhow here in Germany, the previsions for days with empty batteries were fairly accurate.

 

[schmism]

Knurlgnar is back?!?! what? I was a regular watcher of him but he had a 5 year gap in posting videos.

I was ready to dismiss it as a shill video with a non-listed paid-for-by-trogan but he had informative good videos 5-7 years ago...

 

[Steve_S]

I'd like to point out that FLA companies are far & few between, many are now owned by holding companies which retained the "brand" label.

I've replaced my FLA (now a backup bank) wih LFP which cost e less than if I was going to replicate the FLA installation again. With LFP though I got DOUBLE the storage capacity. 428AH FLA versus 910AH of LFP. LFP charges Faster and requires no watering, babysitting or extra care like FLA. The old adage that everyone always "kills" their first set of FLA is very true, are you willing to chuck big bucks away in < 5 years ?

Compare costs and lifespan plus useable capacity and it really is a no brainer.
If buying Full ON commercial LFP like SimpliPhi, Relion, BatleBorn, Rolls Surette or Trojan LFP your in deep dollar country BUT that is giving you a min of 10 years warranty and properly fully Matched, Batched, Binned identical cells.

Tesla 24V Packs are even selling for around the $1500-$1900 mark but I would not use an EV battery for an ESS, voltage curves just don;t quite cut it with regular equipment.

IF considering options, I very strongly urge you to do due diligence & research your options and consider / weigh them out. It is your wallet to do whatever you want to do but a happy spouse when you do not throw away good money is VERY VALUABLE ! and can make your life so much easier...

PS: FLA offgasses, must be in a vented cabinet and not within a residential space. Some folks ignore or go around it and later regret it...

 

[toms]

I’ve set up dozens of fully off grid systems, you size your batteries to cover one nights useage - and run a generator if your batteries aren’t fully charged at sundown.

This is by far the cheapest (and most reliable) method for power off grid.

Average power use where i live is 20kwh/day, most of my systems are sized for 10kwh overnight. I haven’t seen an off-grid system capable of doing this for less than 100k without a generator. My system is less than 30kAUD.

LiFePO4 is a fraction of the price of Pb.

 

[rin67630]

I’ve set up dozens of fully off grid systems, you size your batteries to cover one nights usage - and run a generator if your batteries aren’t fully charged at sundown.

I design unattended off grid instruments. Running a generator is not an option.

LiFePO4 is a fraction of the price of Pb.

For that usage, being discharged every night, there is no alternative to LiFePO4.

 

[Trukinbear]

It totally depends on your situation, what you are comparing, and how. For my particular situation, the maths indicated there was no other choice than lead-acid, but depending on what my goals were and how I'm comparing it the answer would have been different.

For example, are you comparing x dollar vs x dollar, x Ah vs x Ah, or something entirely different like x Lb vs x Lb when specifying the battery(s) to compare... and then there is usage. So many variables, what is best for me probably won't be best for you, and if it IS probably for an unrelated reason. A comparison between a lead-acid and a LiFoPE battery bank will be very different if with the same usage you are comparing $20,000 worth of each, than comparing 1000Ah of each, or 1000# of each. Your mileage may vary.

 

[Cal]

On the data sheet they say: if charging time is limited, contact us...
You may charge faster for a couple of hours.

I know the RV world fairly well. Despite the documented 10% or 13% charge rate, most RV'ers consider 30% of C20 the max charge rate for LAB.

 

[rhino]

After having to haul four 12V 220AH AGM batteries out of the basement my back thanks me for replacing them with LiFePO4.

I just don't get how you can justify the high maintenance of a FLA compared to LiFePO4. Even an AGM I consider dangerous since mine died by filling the basement with hydrogen gas.

 

[Freep]

For me weight is an issue. The heavier, the better.

That's interesting. Why?

 

[Trukinbear]

After having to haul four 12V 220AH AGM batteries out of the basement my back thanks me for replacing them with LiFePO4.

I just don't get how you can justify the high maintenance of a FLA compared to LiFePO4. Even an AGM I consider dangerous since mine died by filling the basement with hydrogen gas.

Just speaking for myself, the difference in delivered price between the FLA and the LiFePO4 paid for the rest of my system. If I was rich I'd have looked at it differently... maybe.

 

[Steve_S]

When I bought my FLA, anything Lithium was Insane to Lunacy cost wise. Now with LFP at PARITY.. it's a no brainer.

Pssst.... some of us, who live in regions which can be 40C in Summer & -30C in Winter and can make do very nicely with < 4kWh usage a day even with short sun hours in winter may have a slightly different view / opinion. Rule One of Offgriding, conservation is far cheaper than generation & storage.

Weight example.
8 280AH cells @ 5kg each = 40kg/88.1lbs. That is one 24V/280AH/7.168 kWh battery pack.
X2 of above is 560AH, 80Kg/176.2lbs.

8 Rolls Surette S6 L16-HC, (formerly S-550) 55.5 kg (122 lbs) = 444kg/976 lbs. for 24V/956AH gross / 428AH net @ C20.

That says a heap on it's own with price parity for 16 LFP cells vs 8 Heavy Leads.

 

[Trukinbear]

When I bought my FLA, anything Lithium was Insane to Lunacy cost wise. Now with LFP at PARITY.. it's a no brainer.

Pssst.... some of us, who live in regions which can be 40C in Summer & -30C in Winter and can make do very nicely with < 4kWh usage a day even with short sun hours in winter may have a slightly different view / opinion. Rule One of Offgriding, conservation is far cheaper than generation & storage.

Weight example.
8 280AH cells @ 5kg each = 40kg/88.1lbs. That is one 24V/280AH/7.168 kWh battery pack.
X2 of above is 560AH, 80Kg/176.2lbs.

8 Rolls Surette S6 L16-HC, (formerly S-550) 55.5 kg (122 lbs) = 444kg/976 lbs. for 24V/956AH gross / 428AH net @ C20.

That says a heap on it's own with price parity for 16 LFP cells vs 8 Heavy Leads.

At parity with what? Seriously I could have had 986Ah @ 48V delivered to my rural location with California sales taxes paid for less than $5000? I had no Earthly idea. Please point me to deals like that.

 

[schmism]

At parity with what? Seriously I could have had 986Ah @ 48V delivered to my rural location with California sales taxes paid for less than $5000? I had no Earthly idea. Please point me to deals like that.

Lishen 270ah-272ah cell group buy.

Ok, this will be a longish post but I want to lay some foundation before taking orders on these cells. Eve 280ah cells appear to only be available at this point from suppliers that want a premium price for them From everything I can find, Lishen is extremely popular in China but has yet to get...

diysolarforum.com

270-280ah cells drop shipped from china, with support from a US member. ~$1700 per 48v set. 3 sets and all the benfits of LFP vs FLA

 

[rin67630]

[weight]
That's interesting. Why?

Because I place my instruments on other's property I can't dig a concrete basement. I need the weight for stability to hold the panel.

 

[rin67630]

Pssst.... some of us, who live in regions which can be 40C in Summer & -30C in Winter and can make do very nicely with < 4kWh usage a day even with short sun hours in winter

How do you deal with -30C and LiFePo?
With FLA you can refrigerate the shaded and insulated batteries since you have excess energy anyhow.
But in the winter with only scarce energy available, I can't afford to warm up the LiFePo batteries > 0C.