Chinook RV

Glad I wasn't just telling you everything you already knew while you rolled your eyes (course maybe you still did )

BTW, I have panels that are the same "narrower" dimension as yours (not Renogy) and got them for the same reason: The least roof overhang. (There are some 70 watt panels that are only 13.5" wide, but they are fairly inefficient so are large for what you get (something like 13.6" by 58").

Here is an idea for your future next 200 watts: I was at first going to put all of them on the roof (four panels, 470 watts total) (I have the space because I don't have a TV antenna), but then almost by accident decided to keep two for "ground panels." The way it worked out was this. Before I installed my panels I needed to use them, and plus I just wasn't sure how many watts I wanted, etc.

So I took two 100 watt panels (that I had for another project) and set them up as ground panels with no panels on the roof. In other words, they are on a 25' tether and that joins up to the controller that is inside. Well, after a year of using them I found out two things. One is that 200 watts is more than sufficient for me, year around, and the other is that I LOVE having ground panels and being able to park in the shade but have my panels in the sun (my buddy with roof panels always had to park in the baking sun, but after camping with me for awhile now has ground panels too - so now I have to fight him for the best shady spots ).

So why add roof panels at all when 200 watts is enough for me? Well, the issue is that when I'm traveling from place to place, or doing short stays, I can't always put them out (like say at Wal-Mart, or certain camp sites). Plus if I'm NOT parked in the shade, if I had roof panels I wouldn't have to bother with putting anything out. So for me the best setup is going to be two panels on the roof, and then keep my two ground panels. Then probably at least 50% of the time I can just run on the roof panels. But other times I can put the ground panels out. Say when I'm parked in shade, or in winter when tilted panels are nice (easy to tilt the ground panels and then I never need to bother to tilt and untilt roof panels).

Anyway, just one idea for your second set of panels. May or may not grab you.

My plan is to replace my two group 27 batteries with 4 AGM group 31 batteries with an additional sliding battery tray. Im just not keen on the idea of having loose panels laying around and having to drag them in and out when i want to use them, plus i have a medium size Dog that goes with me every place and i would be concerned that they would end up ruined. I also plan to remove the TV antenna as well as the satellite TV bubble on the roof. I will then build 2 L shaped brackets to mount on the roof and attach the top panel to the brackets with scews, then i will attach ball bearing sliders to the second panel and attach it to the brackets underneath the first panel. I will also have to come up with a lock mechanism that can be released and locked from ground level with a rod. Then later i will add the two additional panels on the other side where the TV antenna is currently.
I lack photoshop skills but heres a basic image of what i plan to do..... I also got an email that the solar kit already shipped via 2nd day fedex so it should be here tomorrow or the next day i guess. I want to have an inverter hooked to the battery bank to convert 12 vdc to 110ac to power an electric house fan and any other household device i may choose to bring along to minimize the need for generator and propane use. I am even considering replacing the dometic fridge with one of the 12 volt compressor style fridge, but i have heard mixed reports on their efficiency. If for instance shtf and the city turned into chaos because of an EMP or other disaster i could load up and head for the hills and not have to be plugged into the grid or have to find propane to heat the thing if its winter time ect....

I'd say you'd have a very good chance of being able to power a compressor refrigerator. I base this on my experience. I have a 375 amp hour AGM bank (I'm a bit "over-batteried" right now with only 200 watts of solar, but that's because batteries should all be the same age and size so I bought them all at once. I don't take them below 75% charged so that I don't "get behind" since I only have 200 watts of solar right now - but I'll be adding roof panels this winter).

So I have 375 amp hours of AGM batteries, and 200 watts of solar (will be more later). I've been running this for just over a year and have only plugged in once (I was staying in a friend's garage and it was pretty tough to get my panels into the sun for more than an hour or two due to shade plus garage, and the receptacle was there...). So basically, I can run indefinitely on my system. I get my batteries up to 100% probably 95% of days.

Granted, I'm not a power guzzler. I come from boats and am used to a fairly parsimonious 12-volt life. But I'm not even using as much power as I could put back with my system. Right now I have a fairly small compressor refrigerator (50 liter), but I'll be replacing it with a 4.7 cu. foot (running the same Danfoss BD35 compressor). I'm thinking my power usage will go up some due to the larger capacity refrigerator, but on the other hand the one I have now is "cooler shaped" with very little insulation, whereas I'll be adding inches of extruded polystyrene to the surround of the "real" one (except the door will remain the same). I removed the absorption refrigerator mostly because I disliked the intrusion into the hallway making it so narrow; but I also didn't mind getting rid of the worries about parking unlevel (I don't camp unlevel, but often might park at an overlook or trailhead that is not super level), and or leaking ammonia or fires. These are fairly small worries statistically, but I still like not having them. But mainly I love the wide entry hall. I went with a shorter refrigerator because I decided to have a counter over it for entry/bathroom type use; but I could have fit a larger one. I also wasn't sure if I would be able to power a larger one, but now I think that I could.

As mentioned above, I don't use lots of AC appliances on inverter. My DC loads are basically lights (LED), computer (plenty, but 12 volt), charging AA batteries (for flashlight and other things), charging phone, running fan (marine fan mostly, so only about .2 amps), and charging power tool batteries. Oh and the big draw, the refrigerator. But so far so good even with just 200 watts. I will enjoy the roof panels so I only have to put out the ground panels when I feel like it. The only times I've gotten below around 85% charged were when I didn't have the panels out for a period of days, so was running purely on battery power. Even then only down to 70% a couple of times. Of course the main thing is how fast can you put it back, and I can get back up to 100% around 95% of days, and to 90% most of the rest of the time (once or twice I ended the day at 85%, but that was literally only a couple of times.

I removed the SurePower separator (it was recalled anyway on my rig) and replaced it with a manual combine switch. Since my solar charger (and AC charger if I ever used it!) are both "smart," and I can keep my house bank up very well with them, I don't have any urge to add "stupid" alternator charging on a regular basis. Not that I have anything against combiners though - if I wanted one I'd add the Blue Sea 7622 without a second thought. I just combine so rarely (and prefer to control it myself) that a switch made sense for me. (I've probably combined three days in the last year.)

I don't know if this is helpful or just TMI - hopefully the former!

PS: Understood about not wanting to deal with ground panels. I wouldn't want to do it with regular aluminum/glass panels. I have a pair of the used-to-be-called flexible panels that are around 1/4" thick and weigh three pounds apiece. They slip right behind the driver's seat back when they are stowed and I barely know they are there. I couldn't do that with glass panels (although glass panels are clearly better for roof use - much sturdier and longer lived). Even though I take good care of them, I'll be surprised if they last five years. But since they allow me to park in the shade.... I'm willing to replace them when I have to. Wouldn't put them on the roof though.

I think i saw your post about interior mods before i actually joined the forum. I like the Dometic fridge in the respect that if one power source fails or isnt available it will use an alternate source, but its just to large to run on DC full time, im afraid i would end up with alot of wasted food. I also considered attempting to cram 4 group 31 batteries in the area beside the OEM house batteries instead of just two. But i decided that it would just be expecting far to much for that floor to support without coming apart, four batteries total is pushing the limits of that small of an area structurally just due to the weight of the batteries combined with bumps in the roads. I do want to remodel the interior and especially the dinette area to open things up like you did, but i will save that for my last chore. I appreciate the input and may holar once or twice when i start installing this solar kit. Do you know what awg the existing wires are on the OEM system? They say i have to replace the wiring with at least 8 awg wires that are included in the kit. Not sure how quickly i will get around to installing the panels themselves because that requires being on the roof and its been between 90 and 100 degrees everyday for over a week now . But i can get wires routed and install the controller and remote monitor ect... Oh and Reyco says they have my order and it wont be ready to ship out for 4 weeks i pretty much expected 4 to 5 weeks but part of me was hoping they had a kit in the warehouse on a pallet ready to go. Just makes me some what nervous that there is over 4200 dollars gone from my bank account for a suspension that i wont see for up to 5 weeks. Oh my other concern with the fridge is that even though i do feed my Dog kibble type dry food, i supplement that with actual meat which i purchase a quantity of, cook up some all at once, put it in containers and store in fridge, but the uncooked portion has to be frozen Yes he is spoiled.... I got him when i busted my head apart and suffered the TBI amongst other injuries, so they prescribed dog therapy so i picked him at 6 weeks old and i treat him like a king to repay the unconditional love he shares with me .

I hear you on backups. With the propane fridge though, they are SO inefficient when running on electricity, that 12 volts is almost useless (as a backup source of power). I mean, they take something in the neighborhood of 20-30 amps if I remember correctly They are just as inefficient on AC power, but if you're plugged in you don't "notice." The DC compressor refrigerators can be had with AC connections as well (it's around $100 extra). Typically that's not extremely needed because if you are plugged in your AC charger is charging so you can run the reefer on DC and it's almost the same thing. But I still got mine with the direct AC option for reasons such as you state. If I have the DC system down for some reason or whatever, I can run the refrigerator directly on AC. I did that just last month at my friend's house actually (for various reasons).

That's not to say everyone should ditch their absorption refrigerator; I'm just discussing options. One "interesting" thing is that if you are equipped to power a compressor refrigerator via solar panels, then it's actually handier than propane in a way. By that I mean that my camping buddy with an absorption refrigerator will have to go get propane, whereas I can just keep "making" my own electricity at the campsite. It's true that one has to get engine fuel and/or dump/fill on a regular basis anyway, but you can do those yourself, whereas sometimes getting propane is a hassle because an "official" person has to do the filling. Then the gas station is open but the propane filler only works 9-5, is sick, is on break, there is a big line, etc. etc. In contrast, now that I only use propane for cooking and heat (and I don't camp in winter up north), my propane tank lasts "forever." That was a side benefit I hadn't really counted on. But of course there is no perfect/one/best solution for most things - so it just depends on each setup/choices/use-case. I primarily boondock, so that's how I'm set up.

Side note on your batteries: I think you are absolutely right not to put in four (which would be around 420 ah, right?). I can't see possibly needing that much, it's a huge amount of weight to carry around, and "extra" battery to buy each time (and they all go bad eventually), and the main thing is the ability to charge back up. If I were doing it again, I might only go for two batteries (250 ah in my case) instead of three, just because I don't think I need to haul around the extra, and that would be 50% of my next battery purchase already in the bank. I'd rather have more panels in ratio, because sure, with huge battery bank you can get through a week of cloudy days, but then you have to put it all back somehow... That said, I'm sure there is a scenario where that would work well (maybe go out for four cloudy days, then plug in at home for a week). But just saying that the hugest battery bank isn't always the best.

On the solar, unless things were changed drastically (and I highly doubt it), don't plan on using the stock wiring or controller. They are way undersized, the controller is poorly located (well, it was on my era - maybe on yours it isn't - on mine it was a good 18' of wire from controller to batteries). That's fine if you want to run fire hose...

I wouldn't even "trust" any manufacturer's suggestion. Not because I think they aren't trustworthy, but rather because it is so easy to calculate the voltage drop for yourself (online calculator). Then you can decide how much power you want to throw away, where you want to locate the controller, what size wire to use, etc. They can throw out reasonable numbers... for their decision on what's reasonable. My ever-mentioned camping buddy had a professionally installed system and it was not sloppy looking or tiny. And yet when we re-did it a couple of years ago, we found legs that had HUGE voltage drop. He was having trouble getting charged back up every day, and his batteries were not lasting very long. We made more than a few changes, but the really big one was eliminated voltage drop. There was lots to get rid of. Now he's back up to 100% every day in the morning, and planning to replace his absorption refrigerator (same one as in the Chinooks) with a similarly sized compressor unit.

If you like, I could run some numbers for you. Not to horn in, but only if you are interested. What I'd need to know is these things:

1) Size of panels (specs not physical size), and length of wire run(s) from panels to controller. Also if you plan to wire in parallel or series parallel.

2) Length of wire run from controller to batteries (or bus bar).

Once you have those figures in hand, then it's a matter of you can have shorter/thinner wires, or longer/fatter wires for the same ultimate specs. If you run the panels in series (i.e. you'd put two in series and then the second two also in series and the two pairs in parallel), then you will double your voltage from panels to controller, which halves the amperage, which halves the voltage drop. In other words, skinner wire over a longer run. (You have to have an MPPT controller to do this effectively.)

Fun to have you on board and doing all kinds of mods

PS: Just read about your pup. Sounds like a great companion, and pup has a great life. Win/win! Keeping a consistent temperature is one of the "advantages" of a compressor refrigerator. I put that in quotes because it's not that an absorption model can't do that. They are just a bit slower to respond to changes (i.e. you put "warm" food in), and they do tend to vary a bit more in my experience. Of course you do have to have the power to run the compressor refrigerator, but it sounds like you will have that. OTOH, one thing at a time, right? (Or should I say "ten things at a time, right? " I try to keep it under an even dozen )

Well before i do anything i have to sit down and read any documentation included in the solar kit along with install instructions and any requirements they may have for warranty purposes ect.... such as minimum wire gauge requirements, controller location, ect... then i can finalize my plan of attack. The fridge thing will be addressed along with the interior remodel at a later date, but i still like to kick around ideas in my head while i wait. I do know the controller is a good quality smart MPPT controller 40 amp with the remote monitor display. I enquired when i ordered as to if it would be ok down in the battery compartment and he told me not unless it has good air circulation in there. That said, it would limit where i can put the thing and would also be the determining factor in wire lengths ect... It may end up having to go in the overhead compartment inside which i didnt want to do really because of the heat it probably puts off. But we will see when it gets here, exactly how large it is ect....

The conventional wisdom was always to put the solar controller as close to the battery compartment as you could, but not IN the compartment. A big reason for that was flooded cell batteries, which can offgas. Now many of them say it's okay if you have other types of batteries (AGM, Lithium, etc.). I still wouldn't put it right above them.

They do put off some heat but not huge amounts. I have mine under the couch mounted to the outside of my battery box and I can monitor the controller temperature - it doesn't get particularly hot. Not that the couch is sealed off underneath of course, and I do have around 4" below and 4" above the controller fins, plus nothing packed up against it.

You don't really want voltage drop anywhere, but *especially* not after the controller (on the way to the batteries). At that point the controller is putting out the very specific voltage you have set it to (depending on the specs in your batteries' manual), and any voltage drop not only wastes power but changes that voltage (that you just so carefully set....). Since it's at its lowest voltage on that leg (around 13-14 volts), it's also more prone to voltage drop for a given wire size and length (the lower the voltage, the higher the amperage, and the more the voltage drop). Before the controller, even with panels in parallel, you might have 17 volts or so, so not as much drop (higher voltage equals lower amperage equals less voltage drop). Also if you lose power on the panel to controller leg, you do lose power (booo), but your controller has not yet put out its specific voltage tailored to your batteries' needs. So the controller may have less power to work with, but it will still put out the programmed voltage. Of course best to minimize it everywhere.

If you run your panels in series pairs, then the voltage coming in will be around 35 volts, so the leg(s) from panels to controller will have much less voltage drop for a given length and wire size. Also the MPPT can then theoretically see adequate voltage earlier and later in the day and harvest it. Of course there are a number of considerations as to setup and etc. Sounds like you are the type who will study up and then proceed. It's great fun to be able to "make" your own power. And so doable now that panels no longer cost as much as they used to (we thought we were living like kings with one 35watt panel years ago on a boat... wow, we can carry less kerosene )