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There are a number of sticky posts concerning off grid systems that you should read. The first thing that you need to do is find out how many watts each of your items use and then determine how many hours per day you want to use them. Then follow the rest of the trail to find out how big a system you will need and how much it costs.
The sad part of all this is that to go totally off grid you will not be able to run much of anything without spending a real lot of money on a battery system. Most people don't realize that an off grid system is more money than purchasing a very expensive sports car. Then to make matters worse your very expensive batteries will need to be replaced in 3 to 5 years no matter how good they are or how much you use them.
If you want to go off grid then using a small LPG or diesel generator with a very large fuel tank will be less costly then using a solar pv system with batteries. The solar part will help reduce your generator usage during the day but forget about using batteries at night or during a non sunny day. They are just too expensive. -
Deep cycle is a much abused term.Originally posted by warlord2529
Car batteries are cranking batteries that supply short very high current loads and are immediately recharged, and also level out demand fluctuations while the engine is running.
They will not survive many charge-discharge cycles if drained too deeply.
Deep cycle batteries are intended to be deeply discharged before recharging but are not called upon to deliver really high currents at any point.
Hybrid batteries, sold for marine use powering loads while the engine or generator is off, for powering golf carts, etc., can be somewhat deeply cycled, but can also deliver high currents from time to time. Most marine batteries are the hybrid type.
If a battery lists ColdCrankingAmps (CCA) or Reserve Capacity (RC), it is not a true deep cycle battery, but may or may not be a pure cranking battery.SunnyBoy 3000 US, 18 BP Solar 175B panels.Comment
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Deep cycle batteries are the type you would need. But since you don't know how many watts your equipment needs to run I would say you need a whole lot of those 100ah batteries. Along with the batteries you will need a good charger(s) and inverter(s). Again the size and cost will be determined by how many watts you are running and for how long. You work the formula backwards.Originally posted by warlord2529
Lets say you have 1000 watts and you want to run it for 5 hours. That equals 5000 watt hours.
You then divide the 5000 watt hours by the 12 volts to get your battery amp hour rating which would equal 417ah.
Since batteries can't be over used you size your system on your amp hour need times 5 or about 2100 ah. So if you use a 100 amp hour battery that would be 21 of them.
See how this starts to add up. We haven't even discuss the number of pv panels you will need.Comment
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The big tv and Xbox will suck the batteries down very fast. Best place to be in an emergency is with a group of family and friends, not alone in the woods. Sitting duck comes to mind.
A good system, even small one, would be thousands of dollars. Plus the structure and all the rest. I just put in a large shed, which is two stories and 8kw solar and spent over $50k. No batteries either. I think you saw the price of the batteries and ought it might be cheap. However, that is like seeing the price of a good set of tires and thinking a car is not too expensive. To do off grid right takes a good sum of money.PowerOne 3.6 x 2, 32 SolarWorld 255W monoComment
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Just for the heck of it, i got the wattage off the devices i planned on using at a minimum in the hideaway. The laptop reads 65 watts, TV reads 48 watts but says typical use is 28 watts, the Xbox says 120 watts and the small fridge is around 90 watts and 65 watts for a battery charger for cordless power tools plus throw in a 60 watt light to see at night and charging up my cell phone and that about covers it. the ac unit was a bit overboard. not sure if these devices use that much power per hour or every second that there turned on. If anyone wants to come up with the requirements please feel free.Thanks again.Comment
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That is how much energy the use every second when used. You are halfway home, now all you have to do is determine how long you will run each item daily so you can find out how many Watt Hours they consume in a day.
Watt Hours = watts x hours
So determine how many hours you will operate each item and total up watt hours.MSEE, PEComment
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I found a great web site that gives good tips for someone like me that only has a small clue of what there doing. I don't think it breaks forum rules. At least i hope not.
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Please read the stickies at this page:
http://www.solarpaneltalk.com/forumd...ectric-systems
You first need to
Calculate the energy needed by your appliances Volts x Amps x hours = watt hours
Use a solar insolation table to figure the useable sunlight for your area
For off grid, you need 2x the PV wattage x solar hours, to = your Load Watt hours. Also needs
to meet battery minimum charge rate.
Batteries need to be about 8x the Load watt hours.
the actual calculations in the stickies are more correct than my rough paraphrasing above.Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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Yeah he is looking a low 5 digit$ not including any after the decimel point.MSEE, PEComment
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