Off grid, choosing a system parts or DIY

:blush:Im so excited to find your forum! I really like it. People are sharing and helping each other. This is sweet. Well, I am reading alot to try to self answer some questions I have yet I don't find yet what I am looking for so here goes:

I want to know what to buy. I plan to cycle my major items (A/c, hot water heater, fridge) so that when I wash clothes or use the hot water heater for 1-2 hours per day, I will unplug the A/C. If I am using the A/C I won't use the hot water heater. I don't mind downsizing my plug ins to try to attain my solar system now. Because I dont think I can afford a solar system to support all my needs at the same time, like if I cook, wash clothes, take hot shower, run laptop, lights on, etc. I don't need to be a total yuppy. I can afford $2000 for entire system and I wonder if I can get a system that supports my needs for this money. I may pay a little more but I have been studying alot to try to determine my usage. Kindly critic, help, advise, or make jokes. I contacted Evergreen and will try to get price and see if I can buy from them. I am corporation so I can provide them with TX id number as a wholesaler/reseller since this applies.

I plan to get a hot water heater (hwh) that is 2.5 gall or 7 gall, they seem same in energy demand just maybe wiring is 220 or 110, I have to check that. Heat capacity is 1500 watts it says so that is, i think, 1.5kWh x 2 hours per day x 30=90kWh monthly I may use a timer or just plug it in 20 minutes before my quick shower, is this doable? Probably I'll shower twice per day and use the hot water heater total, 1 hour per day but I estimate for 2, I dunno.

A/C 5 hours per day during season x 800 watts= 4kWh x 30=120 kWh monthly
Fridge 42 monthly
3 lights, usually 1 or 2 in use but maybe 3 so I lean toward safe side. 40kWh
washer-I think 20kWh monthly. I will unplug fridge & make sure A/C & hwh are off
laptop 11 kWh monthly
hotplate 30 kWh mo.
tabletop oven 50 kWh
tools, sometimes I will use drill, etc, then I will unplug fridge, turn a/c off.

Like I said, I really am trying to attain this off grid and don't mind being ultra conservative as long as I can have warm shower, keep fridge cold, use A/C sparingly, use computer alot, and sometimes a radio, I am good. I will get a wood burning stove and hope and trust this will heat the entire container home, that is about 600 sq. ft open design with 160 sq. feet upstairs. i dont know much about gas and dont want to deal with trying to get propane as i dont drive.

Has anyone checked further on the solar generator? And what about the stik? http://www.solarstik.com/stik_vs_gen.php It has turbine AND 2 solar panels. I could not find the price on this, anyone know?
Should I buy pieces for my solar system or buy a DIY kit on ebay? Im in south usa and will have clear space for the panels. my roof will be a metal container. :cry: I hope I didnt say too much, or presume to ask for help as I am new. Excuse me kindly and I really love you guys.:D Oh, I may get a turbine, anybody have advise? And how often do you all use your generator? If there is a cloudy day or rain I can wait a day and just keep the fridge closed, right? I can't afford anything more right now. Any financing leads are helpful. I didnt know if the solar generator can handle my needs to power everything. My monthly expenses must be very low. Im a gal tired from society going to live in the woods. Peace, thank you.

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Off grid, choosing a system parts or DIY

    conservation is good, but for 2 grand you're not going to get much in the way of renewable energy. what you are planning will still use appreciable amounts of power measured in kilowatt hours or kwh. you will need to know better the amount of power you will use during a day and know that you need to replace that and losses in the process. from there you can save for what you may need with further educating yourself in the meantime. a meter called a kill-a-watt can measure the power over a day if you time it and provided the loads are 120vac and not hardwired.
    http://store.solar-electric.com/kiacpomome.html
    to have an off grid goal is tough to achieve and many go grid tied to reduce their bills. it usually doesn't go much further than a breakeven point as many utilities will not pay you cash for power and often have limited time periods usually ending at the year's end. this is cheaper and more efficient to do it this way. to go off grid will involve an inverter that accepts batteries and grid tie with this can be done with less efficiency and more general costs, but the plus is it will operate for some time without the grid depending on the battery ah capacity and the loads you run. if the batteries receive enough of a charge daily to make up for your usage and all losses then it is self-sufficient at that point.
    as to the examples you have shown i doubt that would do anywhere near what you want and stay clear of small wind turbines at this point as they cost more overall than solar pvs do for the power produced. see the examples of pvs shown here to get a better idea of how much power costs when dealing with pvs;
    http://store.solar-electric.com/hiposopa.html
    also, see the costs of inverters here,
    http://store.solar-electric.com/inverters.html
    and here,
    http://store.solar-electric.com/gridtiesolar.html
    some batteries and their costs and capacities here if you elect this route,
    http://store.solar-electric.com/batteries.html
    generators are not as expensive up front, but with lifespans and costs variable depending on the quality and the capacity they have their place along with their disadvantages. with this and more i suggest you educate yourself better by reading more and another good place of reading is home power magazine. i know this is fairly general, but is about as much as i feel i can do for you at this point providing i didn't forget anything.
  • stephendv
    stephendv Solar Expert Posts: 1,571 ✭✭
    Re: Off grid, choosing a system parts or DIY

    Hi and welcome to the forum,

    It's good that you started by summing up your loads to determine how a big a system you'll need. The bad news is that your budget of $2000 is probably around 20 times too small for the loads you listed. To give you some indication of costs, my planned system which will produce 7kWh per day (210kWh/month) will cost around 25000 dollars. Your AC alone is half that.
    You mention that you're willing to unplug appliances while others are running. This just means that you could save on the maximum inverter output and won't translate to a substantial saving in installation costs. Would be much better if you could reduce your total energy usage.

    Before you despair, you said that you're willing to adapt your lifestyle so there are some changes you can make that will reduce your consumption considerably, so let's start at the top:
    - A/C for 5 hours per day. You need to reduce this drastically or get rid of it completely. Consider planting trees around your new home to shade it during summer. If you still can, get lots more insulation installed to prevent your home heating up during summer. If it's possible get some more thermal mass near your building by for example, putting earth around it. See: "earth berm home" in google.

    - All electrical heating, this means oven, table top stove, water heater will have to go. Gas will be your best option for most of these. For water heating a solar thermal systems with a large accumulator tank is much more cost effective that a solar PV system. To cut down on gas usage during winter you could use a wood stove with a back boiler attached. This will let you heat water while you're heating the home.
    If you absolutely must have some form of electrical heating, then you could choose to use it only when you have your generator turned on.

    - The fridge using 504kWh/year HUGELY inefficient. Modern European fridges can do 167kWh/year. I'm sure there will be US equivalents available. Energy star is a good guideline, but really you should go for Ultra-mega-energy star :D

    - The lights will have to be CFL, max 15W each. 5 hours per day = 225Wh per day.

    A backup generator will be an essential to keep costs down. Other forum members seem to be quite pleased with the Honda EU series, this will provide power when there's no sun and when you want to use your electric stove, for example.

    The experienced off-gridders on the forum will give you a better idea of US costs (when they wake up), but just looking at your budget, even if you do all the energy saving measures I described, I still don't think you'll find a complete system for $2000 dollars.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Off grid, choosing a system parts or DIY

    leds may be better for lighting as you can go lower with power requirements and still have good light at that power level.
    i know it sounds like you're in a bad way right now, but there's no 2 ways about it that this stuff isn't cheap.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Off grid, choosing a system parts or DIY

    Regarding the Solar Stik...

    Don't shell out any money until you have designed the system you will need.

    Personally, I think the Solar Stik is bordering on being a scam site--Flowery descriptions of equipment, nearly impossible power output projections, little technical details, and put that up against an impossibly ludicrous comparison with a cheap 3kW genset cost of operation...

    For example, they say that you can generate 1,000 Watt*Hours per day... For my area, a 100 watt full two axis tracking system would generate an average of 765 Watt*Hours per day in July--and much less at other times of the year... If you add the inefficiencies of a battery and inverter, you get down to 520 Watt*Hours per day in July... Again--that is with a fully automatic 2 axis tracker--not something that you adjust 3x per day.

    Just to compare--a gallon of gasoline in a fairly efficient genset (like the Honda eu2000i running around 400 or higher watt load) has better than 5,000 Watt*Hours per gallon of fuel...

    The 100 watt solar stick + battery + inverter electrical output would be the equivalent of just over 0.1 gallons of fuel per day (July)... Or 3 gallons of gasoline per month.

    Now--if you need only a little bit of electricity (you could run a 50 watt light bulb 10 hours a day in July)--a solar+battery+inverter is not a bad solution... But it is a very expensive solution for random use.

    And--adding a 200 watt wind turbine at the top of the pole is both pathetic (i.e., wind turbine will generate almost zero useful power--typically a turbine needs to be on a 30-60+ foot tall tower for any useful power) and given the Solar Stik should be taken down in 30 MPH winds and above (without the wind turbine even attached)--it is not even safe to leave standing unattended. Plus. Could you imagine trying to take the thing down (solar panels + wind turbine spinning) in 20+ MPH winds?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Off grid, choosing a system parts or DIY

    Ok Neil, it semms you say maybe I better stay with electric. Thank you for your considerations. It may have been confusing when I read about a solar user that has 450 watts and produces 300 kwh monthly and powers all regular appliances. Unless I misunderstood, I just hope I can go solar sooonn. But I need to know what it takes. Weeks of research=nill. Deeper into the rabbit hole. I am just asking these questions in hopes someone may answer them. The reason I ask is because I want to hear the answers. So I hope there are noot too many questions again. I am just a gentle kind girl and send my query with adventure and faith and hope and love. I tried to specify my exact solar needs and then try to quantify a solar system but there are just a few details I couldn't find out yet. Much if the expense of solar is the installers. Any job I have ever done myself has been better then any crew of overpriced workers. I am a do it yourselfer. As such I seek to join the others that have gone off grid and I hear about people usng system that cost $800 to power entire home...but I am not as monastic as you may think and I use a washer machine and laptop. I like ht water and dont want to heat it up in a pot as I have done before. I want a hot water heater and after much research deteremined the tankless demands too much for a solar array that I may get right now.

    How much power WOULD I get from a $2000 system? I think I am missing one essential conversion. >> can anyone help me with this by telling me<<< Given the watts of a system and taking into account there will be 2% or 20% loss, or even 50%, how much power do I GET, approx? what is the formula? And I researched painstakingly how much my needs are, and trying to compare accurately, I just don't get it , can anyone tell me??? how to match it up? I need about 2.3 minimum to 10 maximum power each day, what system WILL give me that much? can it be described as WATTS and how many panels, and how many batteries. this way

    I have a question about what you wrote, that if I can fill batteries enough to cover night time, then it is an effcetive system, this sounds like a good guage. I want to get through the day and night and have reliable power. how many batteries do i need to power fridge, a/c at night when there is no sun?

    How reliable is everyone's solar? Does it ' not produce' sometimes, and why and when? Rainy day? or are there common failures?

    What about discharging batteries only 50% or ruin them, I read about this. How do you know when you discharge 50%? or is it safe to just use all in battery? what if my plugged in items are burdening the system, what will happen?

    If a system is 225 x 4 panels= 900 watts and it is a pretty good system so not much losses then how much kWh will it produce, in good sunny area, approximately? Is it about 50% losses? What does a 900 watt system produce, considering perfect sun, and expected losses.

    And if I am able to spend $3000, instead of $2000, what amount of solar power per day can I get? If my daily need is from 2.3 to 10 total, what size system will support that? I hope to learn these things will help me greatly.

    I will install system myself so no install fees, just sweat investment labor. I seek to buy at wholesale since I am able to do so. Therefore a $2000 system may be a retail value of a $2600 system. Peace.
    I want to not tie to grid at all so I would need batteries. anyone can help me with these questions, thanks much.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Off grid, choosing a system parts or DIY

    Here is a nice website solar calculator: PVWatts

    Pick your state/location. Say Houston Texas
    Pick your panel size: 1 kW (or 1,000 Watts)
    Use 0.52 for derating (assume flooded cell batteries+AC inverter)
    Use defaults for everything else for now:
    [FONT=Fixedsys]Results
    
    Month
    Solar Radiation (kWh/m2/day)     
    AC Energy (kWh)
    Energy Value ($ at 9.7 ¢/kWh)
    
    1      3.68          55        5.33   
    2      4.12          55        5.33   
    3      4.82          71        6.89   
    4      4.98          69        6.69   
    5      5.24          73        7.08   
    6      5.53          74        7.18   
    7      5.43          74        7.18   
    8      5.44          75        7.28   
    9      5.40          73        7.08   
    10     5.19          74        7.18   
    11     4.33          61        5.92   
    12     3.34          49        4.75   
    =====================================
    Year 4.79 hrs sun   802kWhr  $77.79[/FONT]
    
    So, you can see that you would get between 49 to 75 kWhrs per month for that location...

    And, yes, if you have particularly cloudy/stormy weather--you will have dramatically reduced output.

    The above numbers are based on ~20 year average measurements. Some years will produce 10-20% less than average (particularly when your stormy months are common) or sometimes more... Most everyone needs a backup genset anyway at times.

    A 1 kWatt system would could you around $3-$5,000 just for the solar panels--and add another $3-$5,000 for inverters, batteries, charge controller, racks, backup genset, etc... (see links that Niel supplied to our host's webstore).

    Does this help? More Questions?

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Off grid, anyone use batteries and is not tied to grid?

    I agree Bill, the Stik with turbine is only about 7 feet high, accordingly won't be in position to catch those winds that are higher up. I found the price of the Stik sans the propeller and it is $5000. The production is listed as exactly what you figured it out, 0.5kWh per day. That is not much for that contraption. Agreed, the website is a teaser marketing bordering on a scam. With all those Army photos, it looks like somebody got a lucrative military contract to sell them Stiks. Wasteful, only second to the 10 million spent on census PDAs only to have them change their mind and then not use the PDAs after they were paid for.

    I also read about a 8 foot turbine length that produces 400 kwh monthly. Cost was about $700. I have been spidering though internet data trying to weed out stuff and study promising stuff. I like the evergreen website Neil sent me and I am surprised about the pricing though. I feel that many manufacturers mark items high to protect distributors - I have direct sales experience thereof - so maybe Evergreens can be found for less. I dont mind signing up as a distrib. as long as they warehouse and ship for me.

    Do you feel Evergreen panels under 135 or over 135 watts is best? Is there a size panel that functions best? I see you all have your solar system array listed in your sign off, that is super... I hope one day soon to also list my solar array. I have been to job sites where people pay $5000 for tiling a bathroom. I come in, do same job for $2200 and did a nicer job with same materials. So I maybe wrong about me getting solar now as I am hoping to just find bargain pricing and install it myself. I am not an electrician but I have wired up many items. I love reading specs and installing things on my own. If an electrician is needed, my habit is to do the work then hire one to inspect. Their signature validates my work and pleases the inspectors. I just want to have power and I am not rich. So it is survival for some folks. geting off grid means I dont have to pay the UTILITY co about $50 monthly x 12 mo = $600 year. In 2 years that is $1200. In 3 years that is $1800. Solar will pay off for me in 3-5 years. But if I need a system that costs $10,000 I cannot do it. I hope to somehow find out how much power a certain size system produces. that will solve a simple mystery for me. The only way I can understand is if i know how many watts is the system and how many kwh it produces. i dont understand that names and letters and numbers of systems that people talk about. And when folks say that Evergreen is good, I belive that to be true, but couple that with specifications, and I can reach a whole new level of understanding. Maybe I have a learning disability but keep in mind many people do.

    I may try to learn what production in hwh does any system give - and reverse engineer the figures to try to learn about a 900 watts system's possible output. If I find a formula I will cry joy. How did you all shop for your solar - how did you find out about what energy a system can produce?:blush: I have been convinced a $2000 system is powerful then I learned it is not much. Then I relearned that it is more than enough. Then I relearned that it won't do. If I had numbers of what I do need or what the system can produce, I may do better. Anyone have any numbers, I'd love to hear about your system? Please tell me how many watts your panels are, then tell me how much energy you get from them. Anyone use batteries and is completely off grid? I am learning this fourm and I see many mistakes I am making so please bear with me. I never used a forum before. This too cool. :pPeace.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Off grid, choosing a system parts or DIY

    The PVWatts program is a good place to start--use 0.77 for Grid Tied solar (utility power and solar panels + GT/Utility Interactive Inverter)... The extra losses are from charging the batteries and losses in DC to AC conversions...

    In the end, spend as much as you can justify on conservation. It is almost always cheaper to conserve than it is to generate your own power.

    Many people here are off-grid--and others, like me, are on-grid and use GT systems.

    To give you an idea of the costs of power (really rough numbers for illustration purposes only, assuming 20 year investment, no taxes or interest payments):

    $0.10 per kWhr: Utility Power
    $0.15-$0.30 per kWhr: Grid Tied Solar Power
    $0.30-$0.50 per kWhr: Hybrid Power (GT power with Off-Grid backup)
    $1.00-$2.00+ per kWhr: Off-Grid power

    In California, with the high priced power we have (I pay $0.09 per kWhr off peak and $0.30 per kWhr summer peak). And we are looking at $0.60-$0.75 per kWhr for penalty peak power (with "Smart Power" meters). So--you can see that I can save money with Grid Tied power...

    But, I have really worked hard to get my average usage down to 200-250 kWhrs per month (natural gas for cooking, heating, hot water, drying clothes) through insulation, double pane windows, CFL lighting, laptop computers, energy star appliances, and just turning things off...

    Off-Grid power is almost never a cost savings unless you must pay for a mile of utility power to your home...

    As you work all of this out--Use the kill-a-watt meter or T.E.D. (The Energy Detective) or similar devices to log your energy usage for your major appliances...

    Myself, and a few others here, have found that they can save upwards of 50% on their power consumption with conservation measures... Many times, it is just the realization that leaving a couple desktop computers on 24x7, kids leaving on the 65" TV, and lack of attic insulation are a killer.

    If you have an all-electric home--using propane for heating/cooking, lots of attic insulation, new high efficiency heat pump, perhaps a desuperheater for hot water, etc. can all help reduce charges...

    Solar thermal/hot water/space heating can also be both a good investment and a DYI type project. But does require more maintenance (pumps, tanks, leaks, etc.) than a good GT system.

    Really run the numbers on any type of Solar RE system... Very seldom are they cheaper than utility power (if you are already connected)... If you are a mile or more from the nearest utility feed--Solar RE Off-Grid systems can be competitive--But, again, if you work hard on the conservation angle first.

    And, with conservation, you are introducing less heat into your home--potentially reducing your A/C costs too.

    -Bill

    PS: Generally, larger panels (100-200+ watt) are cheaper to purchase and install (less mounting hardware, wiring connections, etc.)... As long as you are working with "brand names"--shop on a $$$/Watt basis for your hardware.
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • RandomJoe
    RandomJoe Solar Expert Posts: 472 ✭✭✭
    Re: Off grid, choosing a system parts or DIY

    Just to give you my data point - indicative of probably not much really... :p - I spent about $6,000 for my small off-grid system. And it would be doing good to keep my refrigerator going 24x7!

    It consists of four 135W panels, an Outback FM-80 charge controller, six T-105 batteries, and a 1500W inverter (Samlex, not the top of the line, but pure-sine to keep things happy) as well as all the necessary ancillaries (panel racks, breakers, fuses, so forth). All labor was my own, so not factored into that number. I also managed to score some free wire where it mattered (recovering some heavy-gauge pieces from a mechanical room demolition job) which saved a fair chunk of money.

    The battery bank is large enough to handle the fridge (1.6kWh/day) for a couple days with no charging before dipping below the 50% DOD point. During the summer, my solar panels could *just* keep up with that daily, during the winter I would probably have to supplement with the AC battery charger (either using grid or generator). Note that while I'm not in the *best* solar insolation location, mine is pretty good - 4.9 hours in winter.

    Do note i say "could/would" - while I designed the system to handle the fridge in a pinch, that's only for power outages. Day-to-day use is to run my ham radio bench and office light/computer, a much smaller load. Those items I can keep going for about 5 days with no charging before hitting 50% DOD.

    A large part of why I did this is because it's just plain fun for me! I enjoy playing with electricity and have always had a fascination for solar cells since I was a kid. If it weren't for that, I doubt I'd have spent the cash - and even with that I have a hard time justifying any further additions. Grid power in my area is just too cheap (economically speaking) and there's absolutely no payback whatsoever. Heck, my electric bill rarely goes over $100, even during an Oklahoma summer with the A/C running.
  • Kamala
    Kamala Solar Expert Posts: 452 ✭✭
    Re: Off grid, choosing a system parts or DIY

    I agree with Neil. $2000 won't get a year-round home very far off-grid. I spent $4000 on my 3 season weekend camper. And it's heating/cooling (no A/C) is supplied by propane! I installed the PV system on August 1st. After 2 months of stellar performance I began to think that I had over sized it. No mater how I tried I couldn't discharge the battery bank more than 15%. The next day, it was in float around 2pm. Then came the gray skies of October in Wisconsin. Two weekends ago we ran it down to 60% capacity. When I arrived the next Friday it was back to FUL on the Tri-Metric. When I left last Sunday (10/11/09) I had it back down to 55%! O the woe! :cry: No sun predicted. Deficit charge fears haunt me. I may need a genset after all.

    We'll see.

    K
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Off grid, choosing a system parts or DIY

    sidenote to kamala and apology to op for the sidenote.

    i see you changed you avatar;).

    i was wondering if many people approach you with seeing your setup? maybe not judging by that lonesome spot in the photo.:p

    a small genny would probably do well to offset the slight overexcursions on battery capacity you are experiencing. at least you won't have to run it too long to make a real difference. if you feel the pvs do well enough charging the battery bank during the off times then possibly expanding the battery bank is in order so as to avoid the deep cycles providing the pvs can still handle the extra capacity of the battery bank, ie keeping a high enough charge rate %. of course even without the extra batteries extra pvs may offset the deep cycles somewhat so you may have a few directions to possibly go in.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: Off grid, choosing a system parts or DIY

    I live off grid and run an AC, I have about as minimal a system to do this, did the install my self and got deals on several items (power center $200, 1800 watt Prosine inverter $400) and I have @1300 watt array up and running for @$5000 (less $1000 tax credit) I have yet to buy new batteries for the system($6-800), working with the 4 GC batts I had.

    I can only run an AC(@450watts) for 3-4 hours off of the small battery bank with an average duty cycle (the actual time it runs) of about 40-50%. It cools it off at night and I sleep comfortably. I will also run the Ac during the day at times when the batteries are topped off. I only air condition a room 10x16 with 6" insulated walls, built in the shade, made for this use!

    From Your IP adress it looks like you live in Texas...

    If your desire is to be Off Grid, or the property you want to do this is not practical to run electric lines, I'd plan on isolating a single room and insulating it for this use, including floor and ceiling, air tight exterior door, etc.

    For hot water, or luke warm water, I'd go native, with a water storage container outside warmed by the sun, build a simple box around it with glass on the south side. (Where are you getting water? well pumps draw lots of current over short periods.) Plan on heating water on the wood heater in the winter. Or find a propane heater out of a camper. What are you going to cook on/with? I use a gas stove, propane oven, I have a slow cooker, tiny grill and bread machines for sunny days.

    You'll likely have enough Elec to run a small fridge (I do), or a converter freezer (search the site), I also run a laptop for several hours a night and a couple compact floresents, 10" O2cool fans (lots of volume for the wattage) a mp3 player and amplified speakers or a 40 watt stereo amp (sometimes) I just purchased a TV(/monitor), haven't had one in years.

    Before I decided I had to have AC, I live on a truely minimal system @200 watts of panels, a couple Golf cart batteries, charge controler and MSW inverter, you might be able to get that for $800 delivered (pick up the batteries locally) I only had a couple fans in the summer time, no refridgeration, heated with wood, ran some compact floresent lights, mp3 player, laptop for a couple hours. I showered in the community shower house. I had a poor location and needed to watch during long periods of cloudy weather to not run down the batteries too much.

    Maintaining an off grid system is a dance, you get a feel for it over time and live within your system, in your area, meeting your needs. Or you over build, have backup generators and flip the switch with out thinking supplying not only your needs but your wants and desires...

    Look into your reason for going off grid, it is more expensive than grid connect in almost all situations if the grid is near by. It is NOT GREEN as off grid system rarley if every pay back the energy costs of creating the solar panels and recycling the batteries. Your are fortunate in that your desire for AC will mean your greatest need for electric will be when your creating the most.

    As for buying wholesale just forget it, with starting orders of $50,000+ and average size system sales of 15-20K I doubt anyone would consider opening and account for a $3000 sale. It's currently a buyers market and I doubt dealers are working on much of any margin I paid a bit less than $4 a watt for 920 watts of UL listed blemished panels, delivered, 3 years ago, this year I paid less than $3 a watt for 340 watts of 1st quality UL listed panels. Remember there is a 30% tax credit on solar.
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.