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Discussion Starter #1
Ok so heres what I have so far. These are my wattage and daily hour use numbers.

microwave-500w-1hr
gaming console-195w-4hr
portable fan-100w-8hr
curling iron-90w-1hr
Cable box-20w-8hr
well pump-1200w-2hr
15 cfl bulbs-11w-4hr
2 cell charger-4w-8hr
washer-500w-2hr
32in flat screen tv-150w-8hr

Im getting a monthly kwh of 298.506. Which I figure an off grid solar system size of 1809w. So I guess my question is does this sound right? Should I be looking at a off grid system of 2500w? Would 5 100 watt panels generate 500w an hour and over the 5.5 hours of sun I receive in my area give me the 2500w of power I need? Any help would be great thanks.
 

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I'll try to help the best I can, I'm not great on understanding the battery thing but as far as the system I figured you would use 180KW so yes, a 2KW system should work for you. You would need 8 250 watts panels in my opinion.

Again, not for sure about all the battery storage stuff and if that much would over power the batteries. I have the grid tie in system so that is what I'm basing my #'s on.

You may get by with what you posted AFTER your banks are charged. Lot more qualified folks than me on here but thought I would post to get them started. ;)
 

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Wow, you do have some interesting numbers.

A full hour with the microwave? You must use that a lot. A full hour with the curling iron? Wow, you must have some serious hair. TV and cable box on 8 hours a day? Are they part of your work? Two hours of well pump? Wow, you must run a lot of water.

What about refrigeration? (Refrigerator, freezer(s)?)

Conservation is your friend. Solar electricity is still pretty expensive when compared to the grid and trying to use it like you'd use the grid is going to result in either a huge expense for a very large system or frustration at the limited nature of electricity from a small solar power system.
 

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Just howling at the moon
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Ok so heres what I have so far. These are my wattage and daily hour use numbers.

microwave-500w-1hr = 500WH
gaming console-195w-4hr = 780WH
portable fan-100w-8hr = 800WH
curling iron-90w-1hr = 90WH
Cable box-20w-8hr = 160WH
well pump-1200w-2hr = 2400WH
15 cfl bulbs-11w-4hr = 660WH
2 cell charger-4w-8hr = 64WH
washer-500w-2hr = 1000WH
32in flat screen tv-150w-8hr = 1200WH

TOTAL =7,654WH

Im getting a monthly kwh of 298.506. Which I figure an off grid solar system size of 1809w. So I guess my question is does this sound right? Should I be looking at a off grid system of 2500w? Would 5 100 watt panels generate 500w an hour and over the 5.5 hours of sun I receive in my area give me the 2500w of power I need? Any help would be great thanks.
First thing. 5.5 Hours That looks more like the yearly average number instead of the worst month. You need to calculate for the worst case or you will be left in the dark come winter. If you provide a location I can find that number.

By the numbers above you total daily usage would be 7.7KWH. What I didn't see was any phantom loads. They almost always exist. I'd say for safety measures you need to look at about 10KW daily load to cover days that you may need more.

First the battery. One should only use about 20% of it capacity in a day. That is to insure it has a nice long life and gives you 2.5 days atonomy before reaching the 50% level that you should never go below. So:

10KWH * 20% = 50KWH
50KWH / 48V = 1,041 Amphour battery pack.

Incase you're wondering that is 12 of these at $1000 to $1200 each

http://pdf.wholesalesolar.com/battery-folder/surrette/4KS-21PS.pdf

The array.

I'll guess that you have 2.5 hours insolation as that is about average for the US. If you live in the northern part of the states or Canada it'll be drasticly less. To generate 10KWH usable you'll need.

10KWH * 1.2 (MPPT controller) / 2.5H = 4.8KW array

Charge controllers:
2 - 60 Amp MPPT controllers

Inverter size you'll need to look at the list above and figure out how many of them are going to operate at the same time. Total up that number and mulipy by 1.5

WWW
 
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Discussion Starter #5
I live in winnemucca Nevada I'm also hoping I don't need 1200 dollar battery's cause my budget is about 8000 to do this project I there anything I can do to lower the cost? The numbers I put down are kinda a worse case basis.
 

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Just howling at the moon
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Winnemucca has about a 2 hours of insolation in the winter. If you want it cheaper then you'll have to reduce the load.

WWW
 

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If you skrimp on a set of super cheap batteries you will pay more in the long run cause those cheap batteries will have a very short life . . .
 

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Discussion Starter #8
I get the buy now or pay later thing I do but I am operating on a budget of some sort and don't have 12000 dollars for batteries lol. I can cut out the micro the curling iron and the washer no issues we can knock the usage of the well down to about an hour and pretty much cut everything else in half I can live without a lot of stuff it's the wife an son that née stuff lol
 

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Do this:

10--250w panels..................................................................................$2500
6 circuit combiner box/w 5 breakers........ ......$300
Pre-wired power panel...(Outback 3500w & FM80 controller)................$3600
http://www.ecodirect.com/OutBack-FLEXpower-ONE-FP1-1-p/outback-fp1-1.htm
Wire, cables,shipping, etc...................................................................... $500

That puts you at $6900

Buy 8 Deka L-16's @ $250ea from a local Deka dealer...............................$2,000
That will give you 750amp/hrs @24v.

Buy a generator....a 1,000w Honda.....another grand....to make sure you keep the batteries topped off. Run around 1000 bucks.

You're at $10,000.

You could shave a bit here and there......used generator, for example.....assemble and wire your own stuff instead of a pre-wired panel ( but unless you REALLY know your stuff, these are the way to go).....but this is about the bare minimum IMHO to do what you want to do.
 

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Just howling at the moon
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Something not covered, is that well pump 120 or 240? If it's 240 you need to look at replacing it as what TNAndy posted will only handle 120VAC.

And plan on running that generator daily for at least 3 seasons.

WWW
 

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Do this:

10--250w panels..................................................................................$2500
6 circuit combiner box/w 5 breakers........ ......$300
Pre-wired power panel...(Outback 3500w & FM80 controller)................$3600
http://www.ecodirect.com/OutBack-FLEXpower-ONE-FP1-1-p/outback-fp1-1.htm
Wire, cables,shipping, etc...................................................................... $500

That puts you at $6900

Buy 8 Deka L-16's @ $250ea from a local Deka dealer...............................$2,000
That will give you 750amp/hrs @24v.

Buy a generator....a 1,000w Honda.....another grand....to make sure you keep the batteries topped off. Run around 1000 bucks.

You're at $10,000.

You could shave a bit here and there......used generator, for example.....assemble and wire your own stuff instead of a pre-wired panel ( but unless you REALLY know your stuff, these are the way to go).....but this is about the bare minimum IMHO to do what you want to do.
That would be a NICE system!!
 

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Something to think about also is getting rid of the Game console and getting a laptop for games. A LOT less electricity usage.

The sell of the system could cut the cost of a laptop in half.
 

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Something not covered, is that well pump 120 or 240? If it's 240 you need to look at replacing it as what TNAndy posted will only handle 120VAC.

And plan on running that generator daily for at least 3 seasons.

WWW
Yeah.....I started to ask, but didn't.

If he does need 240v, Outback makes an Auto Transformer (PSX-240) that works to provide 2-120v power legs (L1 and L2) that will run 25amp loads. They run around 500 bucks, depending on where you shop.

http://www.firemountainsolar.com/wp-content/themes/fms/pdf/Outback-Autotransformers.pdf

You next option is to step up to twin inverters....about a 2grand upgrade + the cost of the Outback HUB that sync's them in two phase output. That's the route I went.
 

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Discussion Starter #15
well pump is 120 there are no 240 loads in the house at all I have 2 honda eu2000 generators on the house as of now only run 1 unless I'm running the well and I need the 2
 

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Change the well pump to a cistern and slow pump...

Get 2 blue food grade 50 gallon barrels for your cistern
This pump http://sunshineworks.com/shurflo-9300-submersible-pumps.htm

Get a float switch for your tanks like this.

http://www.amazon.com/Float-Switch-...8&qid=1414190739&sr=8-6&keywords=float+switch

Get one of these for your pressure pump.

http://www.amazon.com/Delavan-Diaphragm-60PSI-5-0GPM-Demand/dp/B00F8MIDPO



Get your panels and batteries. You will need 100 amphr @12 volts
and 100 watts of panel.

You can buy a surrette or @ wally world they have a 120 amp hour battery with a 1 year unconditional warrenty. prorated for 5. it's 90 bucks. I challange anyone to find a cheaper battery source.

http://www.walmart.com/ip/EverStart-Group-Size-29DC-Marine-Battery/20531543

This is what I have in service here in north eastern Pennsylvania, cost was about 1500.
I get 300 gallons a day easy.

so your at 8500?

Not bad at all.

The key is using the power wisely.
Don't use moderate power for a long time... Your game console.
Don't use high power equipment... a conventional well pump.
 

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Just howling at the moon
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stan that would be great but i have to get the water up 95 feet from under ground
Not a problem.

See the "We Got Water!" thread

WWW
 

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Discussion Starter #19
What I think I'm going to do is put my two generators on the well pump get a on demand pump and a couple water totes 3 275 gal should work pump the water to the tanks and then pump that to the house with the 12 volt on demand pump kick the well pump off the solar setup all together
 

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Wow! Only 300Kw/mo?!? We just reduced down to 1800Kw/mo. I'm a software engineer and work at home ... so there's always computers and servers running.

... that is 12 of these at $1000 to $1200 each.
So, I'm assuming that if I use 6 times the 'lectricy, I'll need an inline expense of 6 x 12 x $1000? Yeeeeeah ... gonna be grid tied for a while. Oh well ... I'l just wait for vanadium to come down in price :)

Thanks, WWW, for sharing your battery sizing expertise. It's a Rubik's cube to me.
 
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