Need advice on setting up Solar for my 5th wheel

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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #32
    Re: Need advice on setting up Solar for my 5th wheel

    Well, if I was soliciting business, I would have someone that could place a bid to a customer that would work for the customer. A bad reflection on the company they work for.
    If I was shopping at a vehicle dealer and asked for a heavy duty truck that would handle heavy loads, I would expect them to give me a quote on a truck, not a car.
    One of these solar dealers gave me a quote on a bank of batteries, when I told them I had 6 batteries. Now, would a customer be more inclined to buy from them, or less inclined....
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #33
    Re: Need advice on setting up Solar for my 5th wheel

    Right on charge controller and minimum array Wattage. Extra Wattage, even to the point of exceeding the controller's output maximum, will keep the output higher for longer and/or in more varied lighting. As animatt said flat panels on the roof won't be optimum sun angle.

    Monocrystaline panels are the most efficient per area. Something like 18-20% as opposed to polycrystaline (aka multicrystaline) at 14-16%.

    One problem with large Wattage panels: they are very large physically and therefor difficult to manage and mount, especially on an RV application where you can't sink a bolt anywhere you like. There are a few threads on here dealing with others' experiences in putting panels on RV's; search and read so that you know what you're getting in to before you buy any panel. One problem that cropped up was a certain panel meant to be mounted by clamps only; no holes to put bolts through. Fine for a house or ground mount but a bit difficult for something that rolls down the road.
    Aren't these folks selling these systems schooled in what a customer needs?

    I've not seen any indication of it. Most places just sell stuff based on profit and popularity. They simply can't be bothered doing the math and working it out. Like offering a single 100 Watt panel with a 30 Amp controller and saying "it's perfect for" everything. Why, some of them even claim the panels work in all weather!

    NAWS has the sense to fund the forum full of people who know stuff. They don't ever tell us "push these" either. That separation of design and sales is the best thing they could have done. And no, we don't work for them so there's really no retail motivation in the advice given.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #34
    Re: Need advice on setting up Solar for my 5th wheel

    One issue with mounting panels flat to roof (no tilt)... It all depends on how much power you need and when/where you will be camping.

    During summer--Panels mounted flat to roof work pretty well almost anywhere in the US.

    During winter--Flat mounted panels can have significantly less output--Especially as you move north (or south, away from the Equator). US one of these tools to figure out your hours of sun for locations and seasons that you panel on dry camping:

    http://rredc.nrel.gov/solar/calculators/pvwatts/version1/
    http://solarelectricityhandbook.com/solar-irradiance.html

    PV Watts for Minot North Dakota:

    "Station Identification"
    "City:","Minot"
    "State:","North_Dakota"
    "Lat (deg N):", 48.27
    "Long (deg W):", 101.28
    "Elev (m): ", 522
    "PV System Specifications"
    "Array Type: Fixed Tilt"
    "Array Tilt:"," 0.0"
    "Array Azimuth:","180.0"

    "Results"
    "Month", "Solar Radiation (kWh/m^2/day)"
    1, 1.52
    2, 2.60
    3, 3.50
    4, 4.86
    5, 5.95
    6, 6.37
    7, 6.37
    8, 5.54
    9, 4.12
    10, 2.73
    11, 1.56
    12, 1.20
    "Year", 3.87

    "Station Identification"
    "City:","Minot"
    "State:","North_Dakota"
    "Lat (deg N):", 48.27
    "Long (deg W):", 101.28
    "Elev (m): ", 522
    "Array Type: Fixed Tilt"
    "Array Tilt:"," 60.0"
    "Array Azimuth:","180.0"

    "Results"
    "Month", Solar Radiation (kWh/m^2/day)
    1, 3.78
    2, 4.86
    3, 4.74
    4, 5.19
    5, 5.23
    6, 5.12
    7, 5.36
    8, 5.56
    9, 5.18
    10, 4.61
    11, 3.38
    12, 3.01
    "Year", 4.66

    You will get over 2x the hours of sun in deep winter with a 60 degree tilted array next to the Canadian boarder.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #35
    Re: Need advice on setting up Solar for my 5th wheel

    Thanks Bill appreciate it
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  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    #36
    Re: Need advice on setting up Solar for my 5th wheel
    BB. wrote: »
    One issue with mounting panels flat to roof (no tilt)...

    And one other issue... if they are mounted flat to the roof without an airspace between them and the roof, that will reduce their output even further.

    --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #37
    Re: Need advice on setting up Solar for my 5th wheel
    vtmaps wrote: »
    And one other issue... if they are mounted flat to the roof without an airspace between them and the roof, that will reduce their output even further.

    --vtMaps

    So I need to have an airspace to maximize the output? That will work if so, because of the curvature of the RV roof. But if they do need to be flat, I can do that as well.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #38
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    So I need to have an airspace to maximize the output? That will work if so, because of the curvature of the RV roof. But if they do need to be flat, I can do that as well.

    Airspace will help keep the heat down in the panels. Usually its recommended to be 6", but you may not be able to manage that much (going down the road air flow can create lift on panels trying to pull them off). The hotter panels get, the lower the Voltage goes.
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #39
    Re: Need advice on setting up Solar for my 5th wheel

    OK, got that makes sense. I will mount them the way they should be mounted, might have to use more mounting feet or brackets.
    Just got another bid... he wants to sell me 9 panels. This is driving me crazier than I already am..

    Just for your info, I will copy the bid for your comments.. no names of the company or people, wasn't this one; AWS.
    I have put together an estimate for an 80 amp solar charging system that features a dual Solar Boost 3024iL core, and (9) solar panel kits consisting of an assortment of 160W and 135W panels. The actual panels used would be determined during the pre-installation walk-through, but for ballpark estimating purposes, I chose to go with this configuration. This 1315W system is capable of replacing up to 395 Amp hours per day back into your 624 Amp hour battery bank.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #40
    Re: Need advice on setting up Solar for my 5th wheel

    Look real closely at the solar boost brand controller. ... I don't think they work with the Vmp of most GT style panels. You might lock your self into "12 volt" panels with a older design controller.

    Look at the Midnite, outback, Morningstar, Rogue, Schneider, etc brands of MPPT controllers. You probably would be better off in the future.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #41
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    Just for your info, I will copy the bid for your comments.. no names of the company or people, wasn't this one; AWS.
    I have put together an estimate for an 80 amp solar charging system that features a dual Solar Boost 3024iL core, and (9) solar panel kits consisting of an assortment of 160W and 135W panels. The actual panels used would be determined during the pre-installation walk-through, but for ballpark estimating purposes, I chose to go with this configuration. This 1315W system is capable of replacing up to 395 Amp hours per day back into your 624 Amp hour battery bank.

    Avoid this one like the plague.
    First up is a Blue Sky charge controller (3024iL model) which is not a good unit compared to many others. For one thing it is not an 80 Amp controller. On 12 Volts it can do 40 Amps. It has input limitations as well.
    Second is the assorted panels. All work together, will they? Same Vmp so they can all be parallel? Same Imp so they can be put together is series? Probably not. Sounds like he trying to sell stuff on hand - possibly stuff he got stuck with.
    Third item: replacing Amp hours? That may be what is done but that's not how you look at it. 1315 Watts actually could produce 84 Amps on a 12 Volt system. Output is not constant nor is time fixed so saying it can replace 'X' Amp hours is not sensible.
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  • animatt
    animatt Solar Expert Posts: 295 ✭✭✭
    #42
    Re: Need advice on setting up Solar for my 5th wheel

    The idea why people keep stating 80amp controller is that is the big favorite around here. midnite classic lite 150v at normal operating temps it is an 80amp controller

    It is one of the better controllers around. And if kept cool could even do up to 96amps vs most controllers limited at 60amps. This allows one controller to do all panels. Keeps install cheaper and more simple. You could do multiple controllers of another brand but why would you want to spend more. The link i posted to is a cheaper version if really strapped budget.
    But for minimally more you could get full version.midnite classic 150v
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #43
    Re: Need advice on setting up Solar for my 5th wheel

    Thanks Cariboocoot, even as new as I am to this, I smelled a rat. This Solar business might be filled with a bunch of old time 'snake oil' salesmen. I wonder how many folks jump in and buy the wrong products for their needs..
    Thanks for the info Bill, I will refer to the brands making my choice.
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #44
    Re: Need advice on setting up Solar for my 5th wheel

    Thank you, copied and printed for my file. I love the Art Novu ? Deco? design, anyway, love it.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #45
    Re: Need advice on setting up Solar for my 5th wheel

    I will avoid characterizing other store offerings. They may make sense when looking at the big picture and what they stock locally.

    We try for education and doing your own paper designs first. Then you can make better informed decisions based on your needs.

    There are many ways to configure a solution.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • unyalli
    unyalli Solar Expert Posts: 121 ✭✭
    #46
    Re: Need advice on setting up Solar for my 5th wheel
    animatt wrote: »
    The idea why people keep stating 80amp controller is that is the big favorite around here. midnite classic lite 150v at normal operating temps it is an 80amp controller

    It is one of the better controllers around. And if kept cool could even do up to 96amps vs most controllers limited at 60amps. This allows one controller to do all panels. Keeps install cheaper and more simple. You could do multiple controllers of another brand but why would you want to spend more. The link i posted to is a cheaper version if really strapped budget.
    But for minimally more you could get full version.midnite classic 150v
    And don't forget the wizbang jr. Not only can one controller handle 150 volts on the input and put out 80 amps it can end bulk charging when it's actually done not based on a guess.

    -Jeff
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #47
    Re: Need advice on setting up Solar for my 5th wheel

    A few more questions and comments;
    I have decided to go with the Midnight Solar Classic 150 MPPT controller, one item down.. I have the Bogart Trimetric 2020 monitor, the Magnum MS-2012 Inverter/Charger with the ME-ARC 50 remote, and the ME-BTS15 Battery temperature sensor. The battery bank is 6- 225AH Batteries
    Since I have plenty of room on the roof, I could go with a less expensive array; Poly/Mono? I think the Poly are cheaper per watt?
    Another question is voltage of the panels, does it matter what voltage they are with my choice of Controller? and can they be mixed? My want is to have all Voltages the same, but I don't really know enough to make this a buying decision.
    I want as many watts as possible for my batteries and reserve for cloudy, partially shaded panel and so on. I am thinking 6? I know the wattage of the panel matters, but probably too many watts needed for 4. For rough-road use, maybe a extra-large panel, or panels bouncing down the road laying flat is not too good of an idea.
    I want the max I can get, and will size my load accordingly.
    Thank you for your help in this, I want to move on to the ordering stage, but still a bit foggy on what I need.
    Thanks, Ozz
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #48
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    A few more questions and comments;
    I have decided to go with the Midnight Solar Classic 150 MPPT controller, one item down.. I have the Bogart Trimetric 2020 monitor, the Magnum MS-2012 Inverter/Charger with the ME-ARC 50 remote, and the ME-BTS15 Battery temperature sensor. The battery bank is 6- 225AH Batteries

    If you have the Classic & the WhizBang Jr. you don't really need the Bogart Trimetric.
    Since I have plenty of room on the roof, I could go with a less expensive array; Poly/Mono? I think the Poly are cheaper per watt?

    Usually. Not always. Shop around.
    Another question is voltage of the panels, does it matter what voltage they are with my choice of Controller? and can they be mixed? My want is to have all Voltages the same, but I don't really know enough to make this a buying decision.

    Array Vmp has to be high enough to charge the batteries. For a 12 Volt system that means >17. The panel Voltage should all be the same for best results. An MPPT controller can down-convert higher array Voltage to system Voltage, but it can't adjust for various panel Voltages. If they are too far apart you lose power.
    I want as many watts as possible for my batteries and reserve for cloudy, partially shaded panel and so on. I am thinking 6? I know the wattage of the panel matters, but probably too many watts needed for 4. For rough-road use, maybe a extra-large panel, or panels bouncing down the road laying flat is not too good of an idea.

    Six 225 Amp hour 6 Volt batteries = 675 Amp hours @ 12 Volts. You need at least 1050 Watts for this. Stop thinking in numbers of panels: only the Watts matters for power output. A panel may be 130 Watts or 315 Watts: same number, big difference in power (and fitting them on the roof).

    There may be an advantage to smaller panels in that they might suffer less from mechanical stress of the bumpy road. Very large sheet of glass, trying to flex over the area ... smaller may be better. I wonder if any of the RV guys have first-hand experience with large vs. small for reducing breakage?
    I want the max I can get, and will size my load accordingly.
    Thank you for your help in this, I want to move on to the ordering stage, but still a bit foggy on what I need.
    Thanks, Ozz

    Very often mobile applications come down to "how much panel can fit". It sometimes isn't enough for complete charging, but it can increase the run time. So you may have to run the gen while making breakfast and Bulk up the bank, then let the panels take over and finish the charging.
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #49
    Re: Need advice on setting up Solar for my 5th wheel

    I already have the Trimetric, do I need to buy the Whizbang Jr?
    I need at least 1050, would it hurt to oversize for cloudy days, or shading, if so how much oversizing is OK?
    I can fit 9 or more on the roof, I don't want to run the gen if possible, and I was thinking about the smaller panels being more stable.
    Thanks again.
    Ozz
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #50
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    I already have the Trimetric, do I need to buy the Whizbang Jr?

    I believe it comes with the Classic now.
    I need at least 1050, would it hurt to oversize for cloudy days, or shading, if so how much oversizing is OK?

    Well if you max out the 80 Amp controller you'd have a potential peak charge rate of 11.8% which is fine (not into the area of low acceptance/high heat). That would take about 1250 Watts on 12 Volts.
    I can fit 9 or more on the roof, I don't want to run the gen if possible, and I was thinking about the smaller panels being more stable.
    Thanks again.
    Ozz

    Nine of what size? Higher Wattage panels aren't more efficient (except for the 2-4% difference between poly and mono) they're just larger. The 260's I just put up are 40" x 65". I didn't find them to be much more difficult than the 175's I already had, except for the physiological effects of the intervening years between installations (translation: I'm not as young as I used to be).
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  • unyalli
    unyalli Solar Expert Posts: 121 ✭✭
    #51
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    I already have the Trimetric, do I need to buy the Whizbang Jr?

    In short ending amps.
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  • BB.
    BB. Super Moderators, Administrators Posts: 33,613 admin
    #52
    Re: Need advice on setting up Solar for my 5th wheel

    A little longer reply--The Midnite controller families can use the Wizbang Jr. current shunt to measure current into/out of the battery bank.

    So the charge controller actually "knows" the battery charging current and stop charging when the battery charging current falls below ~1% of rated capacity (200 amp battery bank drops to 2 amp charging). Loads do not "confuse" the controller or make it "guess" at what is happening and need an Absorb timer to reduce the chances of overcharging.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #53
    Re: Need advice on setting up Solar for my 5th wheel

    Thanks Bill for your post. I see now It is a sensor for the Midnight Contoller. not just an instrument to monitor and record. I will get it. I might be able to use the same shunt. Can a shunt be shared? I wouldn't see why not.
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  • unyalli
    unyalli Solar Expert Posts: 121 ✭✭
    #54
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    Thanks Bill for your post. I see now It is a sensor for the Midnight Contoller. not just an instrument to monitor and record. I will get it. I might be able to use the same shunt. Can a shunt be shared? I wouldn't see why not.

    Absolutely. Check the wizbang install doc. http://www.midnitesolar.com/pdfs/Whizbang_manual.pdf
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #55
    Re: Need advice on setting up Solar for my 5th wheel

    Hmm, thought I posted something..

    I will order it if it doesn't come with it.

    I need at least 1050, would it hurt to oversize for cloudy days, or shading, if so how much oversizing is OK?
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #56
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    Hmm, thought I posted something..

    I will order it if it doesn't come with it.

    I need at least 1050, would it hurt to oversize for cloudy days, or shading, if so how much oversizing is OK?

    Considering that the MidNite can also be programmed to limit charge current, over-sizing isn't a problem until it gets to the point where you have a lot of money tied up in PV that basically doesn't do anything most of the time. Really I wouldn't go beyond what the max Amps is for the charge controller @ Voltage. The Classic can actually handle up to 96 Amps @ 12 Volts, so that's about 1500 Watts.

    The problem with over-paneling for cloudy days is that it doesn't help much: "cloudy" is a vague term that ranges anywhere from 1% power drop to 100% power drop and you never know which you'll get. When even a little bit of haze is blocking the sun power drop off can be quite dramatic.

    Settling for whatever array size above minimum you can get from the best panel deal you can find that will fit in the space you have without going over the controller's ability would be my suggestion.
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #57
    Re: Need advice on setting up Solar for my 5th wheel

    Thank you so much for all your help and being patient with a newby and my multitude of questions. I am getting closer, have a 2" thick file, I will weed through it and put together a possible order.
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #58
    Re: Need advice on setting up Solar for my 5th wheel

    Hello,
    I have on my wish list and what will fit on my roof of my RV; 3-315 Watt SW 315-XL Mono panels VOC 45.6 V VMP 35.5 ISC 9.35 Amps Imp 8.71 Amps
    also 2-190 watt JTM-190 72M panels, VMP 36.5 volts DC IMP 5.20 amps VOC 43.8 volts DC ISC 5.83
    I want a remote read and control on the controller, or controllers so am wanting to go with the Midnight Classic 150 controller. Question is do I need 2 of them for this set-up?
    I would like for them to match somewhat if so. I hate to buy to of the $600 + controllers.
    Thanks.
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #59
    Re: Need advice on setting up Solar for my 5th wheel

    The two different panel types are not compatible. The Vmp difference is around 24%, which is far too much for them in parallel. (Having recently experimented with >10% array Vmp I found 20+% power loss with; pretty large.)

    Three 315 Watt panels = 945 Watts. On a 12 Volt system = 60 Amps. MidNite Classic 150 will handle 96 Amps on a 12 Volt system.

    Two 190 Watt panels = 380 Watts. On a 12 Volt system = 24 Amps. MidNite Kid will handle 30 Amps on a 12 Volt system.

    That's what I would do, rather than buy a second $600+ controller for 24 Amps.
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  • OzzJim
    OzzJim Solar Expert Posts: 37 ✭
    #60
    Re: Need advice on setting up Solar for my 5th wheel
    Cariboocoot wrote: »
    The two different panel types are not compatible. The Vmp difference is around 24%, which is far too much for them in parallel. (Having recently experimented with >10% array Vmp I found 20+% power loss with; pretty large.)

    Three 315 Watt panels = 945 Watts. On a 12 Volt system = 60 Amps. MidNite Classic 150 will handle 96 Amps on a 12 Volt system.

    Two 190 Watt panels = 380 Watts. On a 12 Volt system = 24 Amps. MidNite Kid will handle 30 Amps on a 12 Volt system.

    That's what I would do, rather than buy a second $600+ controller for 24 Amps.

    But could I get a remote panel or readout with the Midnite Kidd? Wouldn't you want a remote readout of the controller is under the floor space in the Rv and you had all the other controls and panels up in the living space? or is the smaller system not a bid deal to monitor and observe?
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  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    #61
    Re: Need advice on setting up Solar for my 5th wheel
    OzzJim wrote: »
    But could I get a remote panel or readout with the Midnite Kidd? Wouldn't you want a remote readout of the controller is under the floor space in the Rv and you had all the other controls and panels up in the living space? or is the smaller system not a bid deal to monitor and observe?

    You'd be amazed how much I don't look at my charge controller.

    The Kid does have networking capability (RS232/USB) so it could be monitored remotely by computer, as can the Classic. Ask the MidNite people how well the two can co-ordinate (with Classics you can have the Follow Me function use one controller as Master and others as Slave). Also ask about using one shunt/WhizBang Jr for both (the Classic alone keeping track of output for both should be fine).

    On the whole it would not be a big concern as the Kid & its array would be contributing mainly during Bulk charging; the Classic with the larger array would be doing most of the work. Lots of people manage to combine two completely different charge controllers with no ill effects.
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