My 12v Solar Panel Plan.. I would like feedback..

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  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    For the record, I'm not a fan of AC GFI either. I've seen numerous "false trips" and failures of what are very expensive devices. On the whole, I'd only use it for an outlet/service where there's a chance that a person might become the alternate power-to-ground pathway - like around sinks and such.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Maybe I'll ditch the Xantrex SW Pro 1000 idea, and get a Ramsond Sunray 1500/3000 Pure Sine inverter... its $260.. has 3 15 amp outlets and meters.. draws less than 1 amp standing..

    Attachment not found.

    Anyone use Ramsond??
  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    albert,
    if you get one let us know after some time how you like it, any pitfalls, and things you like about it.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    niel wrote: »
    albert,
    if you get one let us know after some time how you like it, any pitfalls, and things you like about it.

    The pricing is close on the 2.. (Xantrex and the Ramsond)..

    The Ramsond has 3+ reviews 4 stars on Amazn, and the Xantrex Pro SW1000 has 13+ reviews and 5 stars..

    Its going to be a toss up.. either way I'll be doing a review.
  • nielniel Solar Expert Posts: 10,311 ✭✭✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    sorry as i meant on the ramsond as most of us are already familiar with the xantrex.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Final notes.. [just to clear up some units--not Watts per Hour, just Watts--that is the rate; Watt*Hours is the total power used/generated. -Bill]

    3- Solar Cynergy (or equal) 140watt panels @ 7.82 amp max each... 12vx7.82a (93.84) x 3 panels =281.52 watts.. x 5 hour avg.. = 1407 watt*Hour
    1- Solar Cynergy (or equal) 100watt panel @ 5.81 amp max = 69.72watts = 348watt*hour per day (est. 5hr avg.)
    Total watt*hours possible for 4 panels = 1755 watt*hours and about 29 Amps VDC.

    1- MorningStar Pro 30 Charge Controller
    4-T105 220ah batteries (=440ah bank)
    1-Inverter TBD.. but leaning toward the Xantrex SW1000 Pure Sine at this time..
    1- Combiner box with all separate fuses for the PV panels..

    This sound like a decent starter??
  • BB.BB. Super Moderators, Administrators Posts: 29,497 admin
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Albert, I edited you post to Watts and Watt*Hours to match what (I think) you are trying to say. We do not use Watt/Hour or Watts per Hour as a unit here... Watts is the Rate; Watt*Hours is the total used.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    One thing that needs to be understood: the Watt hours from the panels is not the same as the usable AC Watt hours coming from the inverter.

    You have three 140 Watt panels and one 100 Watt which total 520 Watts. You have 5 hours of equivalent good sun. Assume an over-all system efficiency of 52%: 520 * 5 * 0.52 = 1352 AC Watt hours possible from the panels.

    You have a 440 Amp hour @ 12 Volts. Assume 25% DOD, that's 110 Amp hours @ 12 Volts = 1320 Watt hours DC, about 1188 Watt hours AC (90% inverter efficiency). This is good because you want the panel potential Watt hours to be greater than the batteries'.

    Your 520 Watts of panel will provide approximately: 520 * 0.77 / 12 = 33 Amps of peak charging current, which is (33 * 100 / 440) a 7.5% rate. That falls within the 5% - 13% standard.

    In my opinion this system would work.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Do you think the Morningstar Pro 30 Charge Controller will handle it ok.. its rate at 30 AMPS..
    and this will be 28.91 Amps (on the max per the panel specs).. though I doubt all panels will max at the same time..
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    ywhic wrote: »
    Do you think the Morningstar Pro 30 Charge Controller will handle it ok.. its rate at 30 AMPS..
    and this will be 28.91 Amps (on the max per the panel specs).. though I doubt all panels will max at the same time..

    It shouldn't have any trouble. As you say the panels won't all max ... possibly ever. As the sun comes up enabling the panels to put out peak current, so does the battery reducing the need for peak current. It won't be put to the limit as panels can't exceed their maximum current.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    It shouldn't have any trouble. As you say the panels won't all max ... possibly ever. As the sun comes up enabling the panels to put out peak current, so does the battery reducing the need for peak current. It won't be put to the limit as panels can't exceed their maximum current.

    I was going to do 4 of the 140 watt panels @ 7.82Amp each.. but that would ring out to a 31.28 amp maximum??

    Do you think I could safely do the 4 of the 1 type and be safe with those combined number??
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    ywhic wrote: »
    I was going to do 4 of the 140 watt panels @ 7.82Amp each.. but that would ring out to a 31.28 amp maximum??

    Do you think I could safely do the 4 of the 1 type and be safe with those combined number??

    You can't really damage the controller by giving it a little bit of extra current that it will probably never really see. Morningstar's specs on the PS 30 say "about 500 Watts on 12 Volts". If you're really concerned you can do no better than to contact them and ask what the upshot of running potentially higher than max current in. They're very helpful in these matters.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    I guess the other obvious thing is.. is the FULL 7.82 amp going to make from the panel down 18' of 8AWG to the controller..

    Looks like a 1.52% voltage drop for 18'.. 3' of 10 AWG on the panel and then 15' of 8 AWG going to the controller...

    Called MS just now and the stated I should be fine.. just put a 30A fuse/breaker just ahead of the PV imput to be sure..
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    The current won't be a problem on 8 AWG, and you'll only have about 1.5% Voltage drop so it should be good.

    Getting excited now? Almost time to flip the switch? :D
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Yup.. now I am considering the MorningStar Pro 30 Controller with Meter vs. without.. the price difference is $60 between them..

    Heres without meter

    Attachment not found.

    and with the meter

    Attachment not found.

    The meter will tell me AMPs coming in from the panels, the battery voltage, and the load draw though I was advised not to hook the AC inverter to the load terminals..

    The standard one only has LED's and no meter..

    I was trying to be cheap but a meter to tell me something about the panels (and battery status) would be nice I think..

    I saved about $90 by ditching the Midnite Solar combiner and brewing my own combiner..

    Would you get the metered version??
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    I am addicted to the multi-display of my MX60. ;) It's just full of fun information. If you want to see what's going on, get the meter. Otherwise you'll never know how close to peak output the panels get. You'll only know if the batteries get charged, or not.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    I was going to install a LP gas INDOOR water heater Eccotemp LP-12.. $340..

    To go with a Shurflo 2088 12VDC pump 2.8 GPH and 45 PSI (7amp max when running).. (it will be on a switch for when I need water) and I plan on using a small (non-voltage) pre-pressurized tank to keep things more 'even' flowing..

    But I found a 12v 250 Watt adjustable heating element from Missouri Wind Sun for $70..

    or I can buy a Bosch/Ariston GL4 120VAC/12.5AMP/1500 watts 4 gal model for $170.. which again I would turn on 1 hour before the nightly shower..

    or the other oprion is the Eemax EMT4 4 gal model for $182 and is 120VAC/10AMP/1200 watts.

    What option would you take for this idea?? Do you know of anything under 1000W usage on 110VAC or anything on only 12VDC with no gas involved???
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    I dislike electric heating of any type. I'd go with gas. Having used both for a number of years.
    But I found a 12v 250 Watt adjustable heating element from Missouri Wind Sun for $70
    Avoid this. 250 Watts is not going to heat much water or not too hot. An ordinary electric kettle is 1500 Watts.
    .. or I can buy a Bosch/Ariston GL4 120VAC/1500watts 4 gal model for $170.. which again I would turn on 1 hour before the nightly shower..
    For electric heat, this would be better. It may take rather longer than 1 hour to heat the water though, depending on how cold it is when it comes in. That is a big load on a small solar power system.

    I'd still go with gas. Or maybe you want to embark on another project and build a direct solar hot water heater? If you've got the sun to run the panels, one of those will give you much more efficient hot water than going through the electric stage first.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    I agree the Eccotemp LP model would probably be the best option.. Its $340 and then just some LP (and they make a gas grill adaptor type fitting if I get into a pinch)... I think someone said 18 hours on 1 20LB tank.. I was thinking the bigger RV size tanks outside would be good.. then hardline it in.. (note.. I need portable LP tanks as my local LP place won't drive down my bumpy road..)..

    I'll do a build on this PV array as I get the parts in..

    Going to start with buying the wires and small breakers first..
    Then the controller, then inverter,.. and do a mock up setup..
    Then when I am ready to GO back to my property I'll order the panels for delivery and get the batteries locally..

    The other project is the plumbing parts.. like $250 worth of fittings and PEX piping..

    Going to do a bag under the plane for $50 (upto 50 lbs).. Lol.. Did it my last trip with 32 lbs of basic tools and cordless 18v drill.. Came home with just a carry-on with my clothes..

    Thanks for all the help.. Keep you ALL posted..
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    After some behind the scene tips via PM's... I am going 24v... using 12v panels in series..

    I'm starting with 6*130W Kyocera 17.6VMP/7.39CMP/21.9VOC (for $1203), 1 MorningStar TriStar TS45 controller w/meter face, & Samlex PST-1000-24A Sine Inverter.. Going to series in pairs of 2 for 3 pairs total.. and 780 Watts of panels..

    This will leave me wiggle room to add 6 more panels (3 more strings in series) and still be below the 45 amp limit of the TS45 at 44.34 amps.. and the VOC should not become an issue with the higher rating of the TS45.. should be ablt to get to 1500 watts worth of PV if I want to at some point..

    Totals up to $1833 without the batteries.. going with at least a 220ah bank.. more then likely 440ah after I hit the Sams..

    The 24v panels for 760 watts of panels (lesser than the 780w above) ranged in price from $1255 to $1390 pending on the dealer used..

    Im going to order the MS TS45 controller and grab a local 12v panel, cheapy 12v battery & 12v inverter and play with my setup here in PA to test some things.. then when I'm ready to fly to TX.. take the 24v inverter and go..
  • themaxx69themaxx69 Registered Users Posts: 23
    Re: My 12v Solar Panel Plan.. I would like feedback..
    One thing that needs to be understood: the Watt hours from the panels is not the same as the usable AC Watt hours coming from the inverter.

    You have three 140 Watt panels and one 100 Watt which total 520 Watts. You have 5 hours of equivalent good sun. Assume an over-all system efficiency of 52%: 520 * 5 * 0.52 = 1352 AC Watt hours possible from the panels.

    You have a 440 Amp hour @ 12 Volts. Assume 25% DOD, that's 110 Amp hours @ 12 Volts = 1320 Watt hours DC, about 1188 Watt hours AC (90% inverter efficiency). This is good because you want the panel potential Watt hours to be greater than the batteries'.

    Your 520 Watts of panel will provide approximately: 520 * 0.77 / 12 = 33 Amps of peak charging current, which is (33 * 100 / 440) a 7.5% rate. That falls within the 5% - 13% standard.

    In my opinion this system would work.

    I'm still a noob, but I thought you could achieve system efficiencies of 80-90%?? If you do everything the "right" way and use the most efficient equipment, ie mppt or micro inverters and proper cabling.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    themaxx69 wrote: »
    I'm still a noob, but I thought you could achieve system efficiencies of 80-90%?? If you do everything the "right" way and use the most efficient equipment, ie mppt or micro inverters and proper cabling.

    Component efficiencies can be high. Inverters will run 90%, so will charge controllers. Wiring losses can be kept below 3%. Batteries ... around 80%. But the over-all system efficiency is bad mainly due to the charging/discharging of the batteries and the large potential Watt hours harvest that can not be had once the batteries are charged.
  • themaxx69themaxx69 Registered Users Posts: 23
    Re: My 12v Solar Panel Plan.. I would like feedback..

    What if most of your electrical demand is while the panels are producing power and your demand is less than what the panels are producing?
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Once the batteries are full and the load demands are met the panels produce no additional power, even though they could; there's no place for it to go.

    This is the big efficiency difference between off-grid and grid-tied: with the GT system there is always someplace for the power the panels can produce to go (the grid). Hence GT systems are far more efficient over-all. Hybrid systems (GT with battery back-up) fall in between the two.
  • CariboocootCariboocoot Banned Posts: 17,615 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..

    I should mention that the panels themselves usually operate at an average output around 80% of their nameplate rating. That's the first big drop, and many things can affect it.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    themaxx69 wrote: »
    What if most of your electrical demand is while the panels are producing power and your demand is MORE than what the panels are producing?
    ^^^ Edited for opposite question...

    Using these numbers:
    You have three 140 Watt panels and one 100 Watt which total 520 Watts. You have 5 hours of equivalent good sun. Assume an over-all system efficiency of 52%: 520 * 5 * 0.52 = 1352 AC Watt hours possible from the panels.

    You have a 440 Amp hour @ 12 Volts. Assume 25% DOD, that's 110 Amp hours @ 12 Volts = 1320 Watt hours DC, about 1188 Watt hours AC (90% inverter efficiency). This is good because you want the panel potential Watt hours to be greater than the batteries'.

    If you divide the max for 5 hours (above 1352) by 5.. you get 270.4 watts per hour... If the A/C draws 550 watts (55 amps) per hour (5-6K btu unit).. you'd still be negative 279.4 watts (28 amps DC) for every hour the A/C runs.. I'm thinking a 220ah battery bank could work with A/C.. if ran with full power to the panels.. If your tried for 3 hours.. you'd kill your 220ah bank about 39% and have about 61% in it when you turned the A/C off.. You'd want the panels to still have sun for another 1-2 hours after you cut the A/C off if you plan on running stuff at night.. Obviously a 440ah bank would be better.. again will full power behind it..

    Another reason I switched to more PV panel wattage..
    I'm starting with 6*130W Kyocera 17.6VMP/7.39CMP/21.9VOC (for $1203), 1 MorningStar TriStar TS45 controller w/meter face, & Samlex PST-1000-24A Sine Inverter.. Going to series in pairs of 2 for 3 pairs total.. and 780 Watts of panels..

    780 * .52 eff. = 405.6 * 5 hours = 2028 watts per day.. for that it would be a negative from the bank of 145 watts (14.5 amps) per hour for every hour the A/C was running... the bank after 3 hours of run would be negative only 43.5 amps.. and would have 176.5ah (80.2%) left for night use if need be..
  • themaxx69themaxx69 Registered Users Posts: 23
    Re: My 12v Solar Panel Plan.. I would like feedback..

    Why not just reposition your panels when you start using the AC? Then take a minute every hour or so to move them again slightly? Then your production jumps way up and battery loss goes down. I thought in an off grid system, battery use is what you want to minimize, given that it is by far the biggest expense, over time. And with 4 or 6 panels, making a simple adjustable system would be easy.

    I am thinking of making and selling small tracking kits because the are so cheap compared to big commercial ones and at least here in AZ, from my initial observations gives close to "full power" from sun up to down minus any cloud cover which isn't often. 12 hours of peak production is a heck of a lot better than a 5 or 7 average.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    themaxx69 wrote: »
    Why not just reposition your panels when you start using the AC? Then take a minute every hour or so to move them again slightly? Then your production jumps way up and battery loss goes down. I thought in an off grid system, battery use is what you want to minimize, given that it is by far the biggest expense, over time. And with 4 or 6 panels, making a simple adjustable system would be easy.

    I am thinking of making and selling small tracking kits because the are so cheap compared to big commercial ones and at least here in AZ, from my initial observations gives close to "full power" from sun up to down minus any cloud cover which isn't often. 12 hours of peak production is a heck of a lot better than a 5 or 7 average.

    I have another post about panels.. yes they will be adjustable for turning and angle.. they will be on posts.. I agree if I have to turn 4 panels after lunch to get more juice I'd be silly and lazy not to..
  • themaxx69themaxx69 Registered Users Posts: 23
    Re: My 12v Solar Panel Plan.. I would like feedback..
    ywhic wrote: »
    I agree if I have to turn 4 panels after lunch to get more juice I'd be silly and lazy not to..

    That's what I'm talking about!:D

    For people who don't want to deal with putting a post and concrete(could possibly do without) in their yard, which wouldn't be much for a small pole and rack supporting say under 100lbs or so, I was thinking about just bolting a pole to say a corner on the house or patio or something like that. Preferably around a corner beam of something like a patio. Much easier than pole in the yard and out of the way.
  • ywhicywhic Solar Expert Posts: 612 ✭✭
    Re: My 12v Solar Panel Plan.. I would like feedback..
    themaxx69 wrote: »
    For people who don't want to deal with putting a post and concrete(could possibly do without) in their yard, which wouldn't be much for a small pole and rack supporting say under 100lbs or so, I was thinking about just bolting a pole to say a corner on the house or patio or something like that. Preferably around a corner beam of something like a patio. Much easier than pole in the yard and out of the way.

    New cabin on 11 acres.. no porch or railing..

    Going to do posts in the ground.. 1 per panel... starting with 6 panels.. fun-fun-fun..

    And so it starts with the 6 breaker combiner box.. $35.. (using it inside)..

    CombinerBox6.JPG

    and the 15 amp breaker... 48VDC/120AC/240AC.. (I am at 3,570 ft for those that may say 10,000 feet..)

    15AQOBreaker.jpg

    I like the fact I can do upto 6 series into the one combiner panel.. its 9" x 12 1/2"..

    Heres my layout 1/2" per square scale.. :p

    layout.jpg

    For my testing here in PA (with a 12VDC panel) I will use my 32VDC max car panel I made last week..

    combinerbox.jpg
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