first attempt going off grid

[killakowalski]

ive been looking at going off grid here for a few years now as grid power is becoming so expensive. after talking with a few solar installers i have decided to go with a 48 volt 4000 watt inverter using 4x105 ah deep cycles in series with 3 strings. only lead acid for now but have been looking at iron for later down the track. picked up 15x250 watt one year old panels from an upgrade and plan to run 7 lots of 2 in series to give me enough charge voltage. any thoughts much appreciated. 20160822_164939.jpg

[littleharbor]

As to charge voltage, you will need 3 panels in series to bring up the voltage high enough to charge a 48 volt bank. Good news is you will be able to utilize all 15 of your panels, (5 strings of 3 panels each). Kinda goes without saying, you'll need a MPPT controller in the 80+ amp range.

[Logan5]

Did your POCO increase rates over a dollar per KWH? If the answer is "no" Then plan to pay much much more for off grid. My POCO provides a KWH of power for 11 cents, With battery replacement and limited storage of batteries, you will likely be paying close to or over a dollar per KWH, in my case 89 cents per KWH more than my POCO. You would be much better off with a grid tied system and a generator for power outages. If you must employ batteries, use them as a critical load UPS, only to be cycled in the event of power fail and to get generator started.

[Sunking]

Why do you want to pay 5 times more than the POCO charges you? Are you rich and hate your money? I do not know what the POCO charges you per Kwh, but to go off-grid you are looking at roughly $1Kwh. Me thinks your POCO charges 20-cents or less. Say goodbye to your money.

Fist thing is a 48 volt 105 AH battery cannot handle a 40000 watt Inverter. It will turn the batteries into boat anchors real fast. To run a 4000 watt Inverter at 48 volts will require a minimum 800 AH of battery with 4000 watt panel system charging them up.

[organic farmer]

15x250 panels = 3750 watts.
48 volt 4000 watt inverter
4x105 ah deep cycles in series = 48vdc with 100ah is not much battery.

I did six strings of batteries for 600ah, a little bit better.

I live in a state where the PoCo does not pay you for power, instead you pay a higher rate for being connected to the grid.

Since net-metering installation costs so much more than off-grid systems costs, we went with off-grid. Though we do have grid-assist for when our batteries run low.

It really depends a lot on what you need for your home. Most off-grid homes in my area have much smaller systems. Some of those homes' systems are over 20 years old and still operating great.

[killakowalski]

I don't have a power company. Is going to cost roughly 50k to get power put on. Looks like I'm going to need more batteries.

[SunEagle]

Batteries for your entire off grid system may end up costing more than using a generator for large loads and solar / batteries for smaller loads.

[killakowalski]

I'm learning. Wish i had seen this site before i started doing stuff. Eventually I will get it right. And with a bit of help from this page and some luck maybe it will work out right.

[Sunking]

Batteries could be as expensive as what the POCO wants to run a line. At least the POCO does not come back ever 5 years to tear out the line and replace it. Batteries in 5 years will be more expensive than today. So make sure you know what you are asking for.

[Mike90250]

$50K for a power line is about the same as you will eventually end up paying for PV, racks, batteries, 2 backup generators, charge controllers, wires, enclosures and inverter.

[SunEagle]

I agree with Sunking. $50k may be the low end of the cost.

Depending on what your off grid life style ends up being some people have spent close to $100k on a solar/battery/wind turbine/generator system and still do not live as comfortable as those that live on the grid.

[killakowalski]

So would a 24 volt setup be better for a general house ?

[Sunking]

48 volt even better.

[Logan5]

If you expect anything resembling standard home power, 48 volts is highly recommended. 24 volts is for a small off grid cottage.

[killakowalski]

So more amp hours then for the batteries. ?