PowerLabGallery · Community design

Tiffin Allegro Class A — Lithium Boondocking Setup

rv · 12V system · Flagstaff, AZ

36-foot Class A motorhome with 600Ah LiFePO4 replacing the original 4×6V flooded bank. Rooftop 800W solar handles most days — can run the residential fridge, coffee, and microwave without the genset on sunny boondocks.

Daily load

5,010 Wh

Daily Ah

418 Ah

Battery

1200 Ah LiFePO4

Solar

1200 W

Load budget

LoadWattsQtyHrs/DayWh/Day
Residential Fridge (Inverter)1501101,500
Microwave100010.3300
Coffee Maker90010.3270
TV / Monitor6015300
Starlink751181,350
LED Cabin Light564120
Interior LED Strip121560
Roof Vent Fan1528240
Freshwater Pump6010.848
Furnace Blower3014120
Laptop6013180
Phone Charger103390
CO DetectorCRITICAL112424
LP Gas DetectorCRITICAL112424
Inverter Standby15124360
Smoke DetectorCRITICAL112424

Battery bank

4 × 300Ah in parallel

Your daily consumption is 418Ah. With 2 days of autonomy, you need 835Ah of usable capacity. LiFePO4 (Lithium Iron Phosphate) batteries should only be discharged to 80% depth of discharge, so you need 1044Ah of total capacity. We recommend a 1200Ah bank (4 × 300Ah in parallel), giving you 960Ah of usable capacity — enough for 2 days without any charging.

Solar array

6 × 200W panels · 125A charge controller

Your daily consumption is 5010Wh. With 6 peak sun hours, a 75% system efficiency factor, and LiFePO4 (Lithium Iron Phosphate) round-trip efficiency of 96%, you need 1160W of solar panels. We recommend 6 × 200W panels (1200W total). This array will produce approximately 450Ah per day at 12V. You'll need a charge controller rated for at least 125A. MPPT recommended — higher efficiency at this array size.

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