Battery bank selection, makes no sense.

mikga45
mikga45 Registered Users Posts: 17
Good morning everyone. I am new here and after being out of the country for 10 years Which 8 of the years were in Iraq and Afghanistan.

At 55 I made costly mistakes and never planned for getting hurt and not being able to pass my physical again. I have spent the last 2 years penniless in the Philippines.

I built a house here that was about 80 percent complete and I am living in it now. The house finally sold and the girl I am living with will get most of the money. I repaired A/C units for a living, years of heavy lifting Left me a bit wore out, curvature of the spine, hytrotopic overseas in my back,gout, which give me a big blister on the bottom of my feet, the second hernia operation on same side sealed my fate and my medical records pretty much black listed me from ever getting a good paying job again.Last year my foot was almost cut off but that was about 8 months ago, I do not know if I can wear boots again.

I should be getting enough money to buy a 40 year old RV, 1,500 worth of solar, some guns for defense and hunting, fishing rod and tackle. I see no sense in living in the city and paying first, last and security for rent, deposits for utilities, I have no job or income and social security is 6 or 7 years away.I can still work but my days of heavy lifting are over. I have a feeling people will not be lining up to hire me. If I could find even a little part time work, mending fences or repairs at houses or farms it would help to pay gas and internet and food.

I will after 2 months, hopefully be fully off the grid, no propane and using rain water and solar. I use rain water half the time in the Philippines anyway.I know I will need gas for truck and generator.convection over or electric hot plate to cook with, I need to find an old wood stove for heat.

I will need a small freezer for game animals I shoot and fish I catch and then a small fridge for everyday living, my computer will be used all the time. I will make vids and write small ebooks on my journey and my failures or sucess's,to help generate a little income.I have books on amazon now but I have no editor and the books have 1 star reviews and only make about 20 dollars a month.

Sorry for all the talk, now to the question.

I will try to get somewhere arround 5 to 800 watts of solar panels.mppt controller, pure sine wave inverter-2 to 3000 watts.The refridge and freezer will run 24 hours a day, freezers only use 20 dollars a year if you only open the door 1 or 2 times a day, both will likly be a/c current,have no money for dc current refridges.

Battery banks are the confusion for me. trojan t-105 at 220 ah wired in series x 4 batteries will give 24v.That one battery bank cost 600 dollars plus core charge and the bank is only 220 ah. I do not understand what happens to the ah on the other batterys? I understand by wiring in series you create one large battery.I can not afford to run the gen always so the proper sizing of the batteries is important.Also 24 volt system is a better choice for starting circuit such as a compressor on a fridge.I know if had 8 battery I could parrale the 2 banks together for 440 ah, that would be over kill and to much money. I just need to understand how the 880 ah total for 4 battery is used.

Will be in America in less than 3 weeks from now, I was born in Norfolk, VA.

If anyone can make and suggestions it will be helpfull. I will be camping on BLM land up to 2 weeks at a time,I will not be able to setup and permanet water catch systems, i will live off the land the best can, I need to find a black mouth cur because I will be living where the bears and mountain lions live, i will try to purchase a 10 mm glock to carry while walking the trails and fishing. i will need to camp in forests wilderness areas for better supply of food and better chances to fish, my girl is no longer my girl. ;) I will be living alone, no money no honey is true ;)

Comments

  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: Battery bank selection, makes no sense.

    First you must qualify for SSD, file and get that flowing.

    The batteries in series you add Voltage, batteries in parallel you add Amperage.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery bank selection, makes no sense.

    Welcome to the forum.

    When you connect batteries in series the Amp hours do not add up, only the Voltage does. But the power is still there. Vis: http://forum.solar-electric.com/showthread.php?15989-Battery-System-Voltages-and-equivalent-power

    Depending on your location you won't be too disappointed with your battery/panel configuration.
    What you've got is up to 2.6 kW hours DC @ 50% DOD (which you don't want to go beyond). The panels themselves may make the available power a bit more if you can make use of them for daytime loads (after the batteries are charged). The actual AC Watt hours will be less due to the inverter's conversion efficiency and consumption.

    I've got a similar set-up at my cabin: 232 Amp hours @ 24 Volts and 700 Watts of panel. I can squeeze 2.8 kW hours out of it on a good Summer day. It runs a refrigerator with no trouble, but adding on a freezer would prove problematic as that can consume almost as much again. It's amazing how fast small load add up too: if I were to leave the computer stuff on all the time it would use as much as the 'frige per day, even though it's less than half the running Watts.

    800 Watts of panel should provide 25-26 Amps of peak charge current, excellent for 220 Amps hours of batteries. You can also get some idea of what kind of yield to expect at your (future) location using PV Watts (although it's meant for grid-tie really): http://www.nrel.gov/rredc/pvwatts/ In AC terms you can expect this: 800 Watts * 4 hours equivalent good sun * 0.52 over-all efficiency = 1.6 kW hours as a sort of 'good day minimum'. More sun, better use of daylight power, and you can sneak that up a bit.

    Sounds like you're not in a position to make mistakes. Some of the mistakes you want to avoid include buying things twice, so go for the best (most efficient) you can afford to get the first time.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    I am only 55, will have to wait till I am 62 for sn:

    I understand the series and parallel part, where the confusion is- 4- trojan t-105 in series for 24v will give me 225 ah battery bank and it will create one large battery instead of 4 batteris.

    what happens to the remaing 675 AH? The 4 batteries would total 900 ah, I do not understand how the 900 ah are used because if i wire in series it becomes one wattery at only 225ah and no longer 900 ah, why? Do the ah in each of the batterys help when you recharge? you don't want to go less than 50% or you could damage your battery so only I used 112.5 ah my battery would have discharged 50% or are we using the total 900 ah which would be a discharge of 445 ah at 50@ usage. Confusioning. with the battery bank in series be charged fully with 5-750 watts of solar panels? Thanks
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Battery bank selection, makes no sense.

    Ouch. Sounds like you are pushing on ahead.

    You will need propane for cooking/heat, trying to use solar electric for cooking with your small system, will not work well.

    In winter, you will need a generator if you want any electric after day 2 of cloudy weather. I'm in northern calif, and have been on generator for 2 days, and no sun forecast for the next 7 days. 2 hours of sun does not do much. (genset runs 2-4 hours a day to charge batteries, and is quiet at other times)

    If you build a cabin, insulate it well, and use a thermal mass heater like a Masonry Heater. 2, 5 gal buckets of wood a day keeps the whole house over 60F. Rocket Mass heaters, you have to sit and feed them sticks to keep them burning.
    http://www.mha-net.org/documents/what-is-a-masonry-heater/ I have a 80gal water tank connected to mine, it preheats the whole tank to 90F before the propane water heater.
    Powerfab top of pole PV mount | 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-Lister ,

  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Battery bank selection, makes no sense.
    mikga45 wrote: »

    what happens to the remaining 675 AH? The 4 batteries would total 900 ah, I do not understand how the 900 ah are used because if i wire in series it becomes one battery at only 225ah and no longer 900 ah, why?
    As stated earlier, adding batteries in series adds the voltages together, not the amperage, but wiring them in parallel adds the amperage together, not the voltage. Like that old saying, you can't have your cake and eat it too.
    Think of it as a little stream falling 100 feet and the power it could produce. Now think of 10 streams of identical flow, but only falling 10 feet each. The potential power in each case is identical. Same with batteries. Parallel them and you get greater flow, but series them and you get greater voltage. Batteries being the same, the power produced in both cases is potentially the same, but the higher voltage series battery would result in less loss in the wiring.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    A mistake would allow me to live with no electric. I have zero experince with solar and I will read as much as I can on placement of fuses and the correct way to set it up. I have a big background with AC elec... and A/C and heat. I have no play money for mistakes, learning is hard to do without making a few mistakes. the freezer is important and it will be 5 cu in size, estimate comsumer electric bill is only 20 dollars, half of a fridge, A refriderator comsumes a lot of power because it is poorly designed, you open th door on the refridge to get somthing and the box gets warmer and brings the compressor on. If the doors are kept close the compressor will not have to run much, the cooler the boxs becomes the less power it uses, a coldbox might only comsume .9 amps at 12 vac. if the freezer is insulate well and maintains its temp it might only run for a few mins a day. I will have to learn to turn things off and get a laptop with good battery life. by laptop has to be replaced it has a dead battery and now keyboard. i am using the on screen keyboard wth mouse clicks.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Battery bank selection, makes no sense.
    mikga45 wrote: »
    I am only 55, will have to wait till I am 62 for sn:

    I understand the series and parallel part, where the confusion is- 4- trojan t-105 in series for 24v will give me 225 ah battery bank and it will create one large battery instead of 4 batteris.

    what happens to the remaing 675 AH? The 4 batteries would total 900 ah, I do not understand how the 900 ah are used because if i wire in series it becomes one wattery at only 225ah and no longer 900 ah, why? Do the ah in each of the batterys help when you recharge? you don't want to go less than 50% or you could damage your battery so only I used 112.5 ah my battery would have discharged 50% or are we using the total 900 ah which would be a discharge of 445 ah at 50@ usage. Confusioning. with the battery bank in series be charged fully with 5-750 watts of solar panels? Thanks

    Amps or Amp hours alone don't tell the whole story. Power is Watts. In quantity it is Watt hours. Watts is Amps times Volts and Watt hours is Amp hours times Volts. So one 6 Volt 225 Amp hour battery has a total of (6 * 225) 1350 Watt hours in it. If you put two in series you get 12 Volts @ 225 Amp hours, but the total power is now (12 * 225) 2700 Watt hours. Of this you can use up to 50% per cycle before you are running the risk of seriously shortening the battery life.

    If you put the two batteries in parallel they would also be 2700 Watt hours, but as 6 Volts * 450 Amp hours. But 6 Volts is not where system operate, and the greater Voltage used to deliver the power the more efficient the system because Amps generate heat which is power lost.

    So four 225 Amp hour 6 Volt batteries all in series is (24 Volts * 225 Amp hours) 5400 Watt hours.
    As a rule-of-thumb you plan the PV array to provide 10% of the Amp hours capacity in Amps as the peak current at nominal Voltage. Or for this example 22.5 Amps @ 24 Volts. That's 540 Watts, but panels on average put out about 77% of their rating so you need to up the array to (540 / 0.77) 701 Watts.

    Of course you have to make allowances for what panels are available to, so you try to come as close to that as possible. More Watts is better, within reason.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    what about using a wood stove for keeping things warm? Will a convection type microwave use too much power? I cannot afford to buy 2 or 3 lbs of prorpane a day for cooking and heat.will have to cook with campfire if I cannot find a better method, for back up to solar maybe a small motor turning a magnetic alternator.That could almost cancel the heavy use of a generator with gas arroung 3 or 4 a gallon it would be costly.I need to find ways for myself and anyone else that woke up one day and discover your finnacial planning failed and now what? I will have a website and make books on the now what. using alot of gas and propane is a expense many don't have, living in rv parks is expensive. living in the blm lands where there are forests can be dangerous from the 2 and 4 legged type and being isolated from people will be a hard life.shtf just happened to a lesser extense. I will create the what if. For the first few months I will be learning and will be using gas and propane, after that the money will have almost ran out and Had beeter have come up with ways to live or it will get only rougher.
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: Battery bank selection, makes no sense.
    mikga45 wrote: »
    I am only 55, will have to wait till I am 62 for sn:
    Actually no, if you are disabled you can get Social Security Disability any any age. Check with an attorney, they can only take or case on a contingency by law. There are several national firms and the fees are limited to a max of $6000 from your final settlement.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.
    Amps or Amp hours alone don't tell the whole story. Power is Watts. In quantity it is Watt hours. Watts is Amps times Volts and Watt hours is Amp hours times Volts. So one 6 Volt 225 Amp hour battery has a total of (6 * 225) 1350 Watt hours in it. If you put two in series you get 12 Volts @ 225 Amp hours, but the total power is now (12 * 225) 2700 Watt hours. Of this you can use up to 50% per cycle before you are running the risk of seriously shortening the battery life.

    If you put the two batteries in parallel they would also be 2700 Watt hours, but as 6 Volts * 450 Amp hours. But 6 Volts is not where system operate, and the greater Voltage used to deliver the power the more efficient the system because Amps generate heat which is power lost.

    So four 225 Amp hour 6 Volt batteries all in series is (24 Volts * 225 Amp hours) 5400 Watt hours.
    As a rule-of-thumb you plan the PV array to provide 10% of the Amp hours capacity in Amps as the peak current at nominal Voltage. Or for this example 22.5 Amps @ 24 Volts. That's 540 Watts, but panels on average put out about 77% of their rating so you need to up the array to (540 / 0.77) 701 Watts.

    That makes it crystal! Lots of smart people here and it's good to know that for the batteries I will need about 700 watts. I do not know if I will be able to afford 700 watts, I will have to wait and see what i have left after get a old motor home and motorcycle to mount on the back to go back in town when i need something.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    I am not disabled, I just can no longer do the work I did before, I cannot lift a 2 or 300 lb A/C by myself anymore.Maybe I can find some places to park in exchange for free land rent and a small salary for doing maintenance work or something like that. It will be a journey in any event. I had high blood pressure and choleterol on my last no past on medical and the doctor added comments about my body being worn out, worked 7 years in the desert sun 12 plus hours a day and the high altitudes of the afghan mountains, Iam no longer a cadilac but closer to a worn vw beetle, everything still works, can still catch the lady
    s if they don't run so fast, cannot outrun a angry hog, I would have to stay and fight.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Battery bank selection, makes no sense.

    read my pm to you as you do not have to be missing limbs or in a wheel chair or even blind to be disabled.
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: Battery bank selection, makes no sense.
    niel wrote: »
    read my pm to you as you do not have to be missing limbs or in a wheel chair or even blind to be disabled.

    +1 if you can't do your trained job and being over 55 they are unlikely to require retraining then you may have a case.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    When I get back to greenville, sc I will try to find a lawyer who will take my case only If we win and maybe he can deduct is fee from my monthly checks. worth a try. Wonder how long it takes from when you see a lawyer till you actually see your first check? I would guess a year or longer.
  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    I wonder if I am on federal land, BLM parked away from everyonee else if there will be a problem running power tools and installing solar panels on the roof.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Battery bank selection, makes no sense.
    mikga45 wrote: »
    .....If the doors are kept close the compressor will not have to run much, the cooler the boxs becomes the less power it uses,....

    uh, not really, the cooler the box gets, the greater the thermal loss is, and the more power is required to maintain the cooler temp.

    I really think you are over-estimating your solar power production, and under-estimating your usage. When your batteries discharge and stay that way, 2 gallons of $8 gasoline will recharge them, or you can let them die that week and buy $800 dollars of new batteries.

    I think the most efficient DIY generator rigs, are made from Axial Flux designs. I've heard of them powered by steam, or any sort of engine,
    Powerfab top of pole PV mount | 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-Lister ,

  • mikga45
    mikga45 Registered Users Posts: 17
    Re: Battery bank selection, makes no sense.

    If the door is closed and the t-stat is happy the contacts will be open and not draw current, leave the lid off your cooler and the ice melts fast, put the lip back on and the ice will last longer. Newer refridges that are frost free might use circuit boards to control them and timers such as heat pump A/C units. Depends on how the design is on the circuitboard, good common sense is to not leave the door open longer than needed. If the box is to cold the compressor shuts off.