E2E Permit Test 2026-04-29T19:18:47
sailboat · 12V system
Daily load
1,260 Wh
Daily Ah
105 Ah
Battery
300 Ah LiFePO4
Solar
400 W
Load budget
| Load | Watts | Qty | Hrs/Day | Wh/Day |
|---|---|---|---|---|
| RefrigeratorCRITICAL | 60 | 1 | 12 | 720 |
| LED lighting | 30 | 1 | 6 | 180 |
| Inverter idle | 15 | 1 | 24 | 360 |
Battery bank
1 × 300Ah battery
Your daily consumption is 105Ah. With 2 days of autonomy, you need 210Ah of usable capacity. LiFePO4 (Lithium Iron Phosphate) batteries should only be discharged to 80% depth of discharge, so you need 263Ah of total capacity. We recommend a 300Ah bank (1 × 300Ah battery), giving you 240Ah of usable capacity — enough for 2 days without any charging.
Solar array
2 × 200W panels · 42A charge controller
Your daily consumption is 1260Wh. With 4.5 peak sun hours, a 75% system efficiency factor, and LiFePO4 (Lithium Iron Phosphate) round-trip efficiency of 96%, you need 389W of solar panels. We recommend 2 × 200W panels (400W total). This array will produce approximately 113Ah per day at 12V. You'll need a charge controller rated for at least 42A. MPPT recommended — higher efficiency at this array size.
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