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creeky
Member
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# Posted: 15 Jun 2015 09:26
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creeky's amazing off grid solar system 2015 edition
Remember: this is top of the line everything
1000 1kw solar panels
1000 solar controller
750 stuff (combiners, wires, fuses)
1500 fancy pants charger/inverter
3000 lithium battery pack 5kw (4kw usable)
500 fridge
giving you 3-6 kw of power daily for 10 years on the battery, 25 years bulk of installation. 10 cu ft fridge
VS: Honda generator (1kw model) and propane fridge
1000 generator
1500 fridge
7750-2500 = 5250 in initial solar cost
savings compared to running a generator using $5 in gas per day.
time gas propane solar
after 1 year 1820 450 5250
year 3 5500 1350 6500 (add 1kw panels, dishwasher)
year 5 9100 2250 6,500
year 10 18,200 4,500 9,500* (new battery pack)
year 20 36,400 11,250 9,500
net savings $40,000 or 2,000 bucks a year.
Hmmm. We can quibble about the numbers. But it takes two years and some months to pay for this really fancy solar system vs gas and propane including some appliance costs.
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littlehouseontheprarie
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# Posted: 15 Jun 2015 09:39
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I want a good solar system and am saving to get one.
But I love my propane refrigerator also.The cost to operate is minimum.
I will probably keep it when I do get the solar system.
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Julie2Oregon
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# Posted: 15 Jun 2015 10:14
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Your system IS amazing, Creeky! And the savings is substantial!
One thing that I know I'll never spring for is a dishwasher. I never use mine now being on the grid with city water and electric. It being just me, I find that it's easier just to wash up my things in the sink after I eat my meal. I feel like I'm working off some of those calories or something, lol.
But you're the solar king around here and you deserve any convenience you want! 
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creeky
Member
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# Posted: 15 Jun 2015 10:49 - Edited by: creeky
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lol. Julie, i'm also a bachelor. so my dishes pile up in the sink until I hear the sounds of evolution creating new life forms. or I run out of dishes. and I have two full sets!
way easier for me to pile plates in a place where I can close the door and nobody can see them. rinse. and then. when i get that day of full sun. push 3 buttons and away we go.
of course I spend the time I save surfing the web 
little. you must live in the US. my propane fridge cost 1.25 a day to run. my much bigger electric fridge paid for itself in propane cost savings the first year. After another year and 2 months I have 500 bucks i get to spend on other stuff.
and that's not including the money I made selling my old propane fridge.
I expect to live another 20 years. x 500/yr. hey I get a bonus 10 grand.
simple economics my friend.
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littlehouseontheprarie
Member
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# Posted: 15 Jun 2015 11:09
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Creeky,
First off I choked reading about your dishes.Reminds me of my old
college days.LOL
Yes I live in the US.I spend about half of that on my daily use on my fridge.
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offgridjunkie
Member
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# Posted: 15 Jun 2015 13:35
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Creeky- What batteries are you using? How long have you been running them? 10 years of service.....really? I have to look into those.
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creeky
Member
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# Posted: 15 Jun 2015 17:21 - Edited by: creeky
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offgridjunkie
Sadly I have 4.25 year old lead acid batteries. the system above is my take on what I would buy today. and is a hint for those thinking of going off grid.  Esp. vs running a genny.
lifepo4. or lfp or lithium ferrous phosphate is relatively new battery tech. it's similar to what mercedes, tesla etc are bringing to us. and balqon already sells lfp ready to plug and play.
has a lot of great advantages. like 10 year service life. no maintenance. no worry about discharging and not immediately recharging. so the two things that kill battery packs (not watering, excess discharge/slow recharge) are taken out of the off grid equation. sweet eh.
the boating community has been using them for over 5 years now and they basically don't buy anything else anymore. the RV crowd is pretty much the same.
if you look at the math it's pretty much break even / slightly cheaper than going lead acid over the lifespan of the battery.
anyway have a google. i have some posts on my blog which you can find through my member info. it details the advantages and an australian fellow who has been running with LFP for 3 years now wrote a cost analysis.
what I find interesting is he doesn't use a propane stove. he and his wife use an induction stove top. with the power in/out profile of LFP it's not a problem.
sort of like my not using a propane fridge. off grid solar has come a long way.
princeton university researchers compared them to the other available off grid battery technologies and they won hands down.
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MtnDon
Member
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# Posted: 15 Jun 2015 18:04 - Edited by: MtnDon
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Quoting: creeky lifepo4. or lfp or lithium ferrous phosphate is relatively new battery tech. it's what mercedes, tesla etc are bringing to us.
I thought Tesla was using the lithium cobalt cylindrical cell like the 18650 cells, not LFP? Or am I behind the times, working with old info?
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creeky
Member
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# Posted: 15 Jun 2015 18:39
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thx. I updated my post.
Mercedes-Benz says only "home- and business-energy storage lithium-ion"
and Tesla is using two different lithium chemistry batts according to ars technica. cobalt which is getting a lot of criticism and they now say is for UPS use. and a nickel-manganese for the daily cycle.
none of which negates you can order an LFP battery today. and the chemistry is well suited to long term energy storage with daily cycling.
google sailboat lifepo4 to see the thread (303 pages last time I was there) on one of the yachting forums. the thread launched in 2010.
btw. 18650 appears to only reference the cell shape and not the chemistry.
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offgridjunkie
Member
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# Posted: 15 Jun 2015 19:38
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Creeky, Darn, I was hoping you were using them. I love the idea and the ability to DOD 80-85% means far smaller battery bank. Don't they also have low charge and discharge rate like c/2 or something.
I am burning up a AGM bank now and project about another year of use before needing to replace it. At that point I think we will really have some good options and I would love a no maintenance 10 year battery bank.
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Gary O
Member
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# Posted: 15 Jun 2015 23:57 - Edited by: Gary O
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Quoting: creeky i'm also a bachelor. so my dishes pile up in the sink until I hear the sounds of evolution creating new life forms. or I run out of dishes. and I have two full sets!
When my wife was out, I'd just eat over the sink, or rather the sink was my dish.
Whatever mess was magically washed away.
aand, instead of fixing something, I'd just eat whatever was left in the fridge, or on the counter.
Ate a leftover salad in a big steel bowl from the counter once.
Wife wanted to know if I'd taken out the compost.
I know I know
Great thread
I'm becoming a believer
and solar is quieter
I'm going to turn off Mr Noisy right now and go to bed
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creeky
Member
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# Posted: 16 Jun 2015 08:35
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Gary O, you. off topic. never.
Offgridjunkie. I'm in the same boat. my batts have been badly abused. especially the first year while I figured things out. Sadly the batteries are still performing well.
as for lfp. Yup. I travel quite a bit and the idea that I can discharge my batteries to 60% soc and then leave them for a year without charging no problem 
it's the most attractive thing about them really. that you don't have to worry about a daily "absorb" charge. so now you can have guests over and burn the midnight electricity and if the next day is raining and heavy cloud. who cares. it'll be sunny soon and you'll catch up on your charge.
plus they are far more efficient charging. None of this lead acid >55% charge efficiency at 90%. What your panels output is what goes into your batteries. So it makes your solar panel set look a lot larger.
really changes the off grid solar equation.
sony's home battery is lfp. and bosch is making an lfp home battery also. here is what bosch says about the lifespan of their home battery
"Another advantage of the lithium battery is its long service life: Renowned independent institutes have calculated that the lithium-ion batteries used in the system last 7000 charge and discharge cycles. In plain text: You can expect a service life of at least 25 years."
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Steve_S
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# Posted: 16 Jun 2015 09:24 - Edited by: Steve_S
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It's a DRAG that I bought the Rolls Surette S-550's now for 2800.00 or so but I needed power this summer. Sure a few companies are making them (LFP, LiIon etc) and more coming on-line but it will be at least 3 years before you can grab a phone and order up some batteries at a reasonable & competitive price.
I expect that my batteries will last a good phew years, being that I'm a Type-A Virgo and it would rub me the wrong way to not care & maintain them.
Now for the 500W Panels and higher voltage output to hit the market next spring, more game changing.
Here's an interesting article on the new generation Bi-Facial panels. Civic Solar & Sunpreme Bi-Facial modules
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creeky
Member
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# Posted: 16 Jun 2015 15:03 - Edited by: creeky
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It's cost on those panels. What do you want. .45/w 17% efficiency or 2.30/w 22% efficiency.
You fibber. With core charge and taxes those batts will push $4k.
You can grab a phone and order lfp and have them in a few weeks today. Still, with the horrible $C the lfp pack would have run you $6k plus taxes across the border.
of course then you would have had a longer life battery with 8kw available. while at 20% dod your Surrette's will give 4. But you can always shorten their life by pushing them harder. 
but ah well. You get to water your batteries for the next 5 or 6 years every month. And don't forget to turn your internet off over night. that's 500 watts saved! and ... don't run the dishwasher or the a/c after dark. and your 2kw solar array. well, with the LA inefficiency more like 1500w.
ahahahahaha. I warned ya. LA is good for small systems. But after dat. meh. not so much.
Hey. It doesn't really matter. Is LFP better? Ya. But your system will last 25 years. The next battery will be some spectacular LFP x 4. So it's all good.
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pizzadude
Member
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# Posted: 16 Jun 2015 15:21
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Very impressive creeky.
Jealous.
Want those lithies🍕
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creeky
Member
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# Posted: 16 Jun 2015 16:25
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me too pizzadude. but I'm stuck with LAs for now. sniff. It's not so bad. Even if I can only run the dishwasher on sunny days and I have to turn the web off overnight.
my niece got back recently from volunteer work in Africa. Funny to think I have 1st world off grid problems. lots of people don't have dishwashers. internet. or even lights. or water pumps.
my solar system would make a whole village happy. Gotta remember sometimes how lucky we are. suffering under the burden of ye olde battery tech.
btw. I posted on your build. your solar system looks really cool my friend. great job. (and I might kid around. but looking forward to seeing steve_s' system built out. should be amazing. good of him to share the buy list.)
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