New design for a motorhome ideas - 24 ft

mafemm5109

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I just bought a 24 ft motorhome to live in, which will require a solar system to keep the electricity flowing during working hours, especially since I plan to be doing mostly boondocking. My idea is not to be dependent on grid, but work from anywhere in the US where there is Cellular coverage.

I live in Washington State and will probably stick around until I complete all modifications and have to be reporting back to the office and as you can imagine, the sun availability is one of the worst in the US

I have decided on a 24V system and have established that I will need ~ avg 3000 W - 4000 W max daily (computer, Monitors, furnace fan, lights, water pump and fridge/freezer (low consumption but not dual fuel) . I can definitely live with less but would like to build the system for this capacity and with a bit of margin due to weather conditions.

The RV currently has a 2000 W generator and inverter/charger (not Pure sine wave, unfortunately - Xantrex 459 20), but would like to avoid using the generator as much as possible. Unfortunately, the batteries are (2) lead-acid marine, but not sure yet the Ah, as I just picked it up and left in storage until I am able to make all the changes needed.

System Panels - I have decided to install (4) Trina 400W panels, since the sun in this area is limited - https://store.santansolar.com/product/trina-400w/

Inverter-charger-converter - I like the all-in-one system, Probably the Growatt 3000

https://watts247.com/product/spf-3000tl-lvm-24p/?wpam_id=3

Initially, I thought of installing (2) BN tracer chargers for a 200 Ah battery bank. The reason for (2) chargers was the VOc for these panels (51 V), connecting (2) panels per charger.

For the inverter, I had not made a selection yet, but would have to be ~3000W Pure sine wave.

Batteries: I am considering the BigBattery option, whether (2) 12V - 170Ah (2175 Wh/battery) link below (4300 Wh).

bigbattery.com/product/24v-li-ion-battery-box-free-shipping/

The Powerball would be nice, but unfortunately it is too heavy, at 192 Lbs ($2000 with shipping)

Also from this distributor is a Li-on battery, similar in price and energy capacity (2) for a 24V system, and much lighter, but the life (cycles) not as good.

https://bigbattery.com/product/24v-li-ion-battery-box-free-shipping/

My question is,
Option 1: Install (2) panels to each Growatt/MPP All-in-one system and connect the output of one to the input of the other, or connect them to make a 6000W unit
Option 2: Connect (1) set of (2) panels to the a bus bar to the battery block thru a BN tracer. Connect the other (2) panels to (1) Growatt all-in-one inverter/charger, and to the bus bar for the battery. This one is less expensive, simpler and the "No-load power" would be less.
Option 3: Connect (2) panels in series to a set of (2) panels in parallel, to lower the Voc, but keep the W under 2,000W with a fuse after each set in parallel directly to the Growatt 3000 and then to the battery.

Is this an overkill? Panels are inexpensive, so I though (4) would be better to keep the batteries charged in the Pacific NW

If you have any good ideas/modifications, they would be welcome and greatly appreciated!

Cheers
 

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Craig

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All you really need if you only need 2000-3000 watts is the one growatt. Your panels and a battery.

I'm confused though what is your max load in watts. Maybe that is why you were thinking 2 units
 

mafemm5109

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All you really need if you only need 2000-3000 watts is the one growatt. Your panels and a battery.

I'm confused though what is your max load in watts. Maybe that is why you were thinking 2 units
Thank you, Craig

Yes, but, the max input to the Growatt is 145Voc, 2000W, and the (4) panels are 51 each, (200Voc, 1600W). It could be cured with option 3, (2) sets of panels in parallel, but cautious in case one fails, not to cause a fire....therefore the fuse.

Cheers
 

Forbisher

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It could be cured with option 3,
(2) sets of panels in parallel, but cautious in case one fails, not to cause a fire....therefore the fuse.
2S2P
2 sets of panels in series.
Then parallel connect the 2 sets.
102Voc
I dont think 2S2P needs a fuse.
 
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