How Many Watts Does an RV Use Per Day?
Last updated: September 3, 2026
First, vocabulary: people say "watts per day" and mean watt-hours per day — an amount, not a rate. Your battery bank stores watt-hours (Ah × volts). This page budgets in Wh, because that's what actually balances.
Budget 1 — baseline 12V loads (no AC, no generator)
| Load | Average draw | Hours/day effective | Wh/day |
|---|---|---|---|
| 12V compressor fridge | 4 A | 10 h (compressor duty) | 480 |
| LED lights | 2 A | 3 h | 72 |
| Water pump | 5 A | 0.3 h | 18 |
| Detection/parasitic (LP, CO, board) | 0.15 A | 24 h | 43 |
| Phones/laptops (via inverter) | — | — | 60 |
| Total | ≈ 670 Wh (≈56 Ah) | ||
Range reality: frugal couples with a 12V fridge land near 40–50 Ah; families with residential fridges or heavy inverter use exceed 100 Ah/day. Your battery monitor over one normal day beats any chart.
Budget 2 — what a furnace night adds
The furnace fan (3–4 A while burning) at a 40% duty cycle for 10 hours ≈ 1.6 A × 10 h ≈ 192 Wh; at 70% duty in hard cold ≈ 336 Wh. It never dominates the propane bill, but it dominates the battery plan on lead-acid banks — see the furnace runtime page for the full breakdown. The propane side of the same night is ≈0.6–1.5 gallons (see propane math).
Budget 3 — air conditioning (the different universe)
| AC duty cycle | Wh per 24 h | Equivalent |
|---|---|---|
| 25% (mild, thermostat discipline) | ≈ 9,000 Wh | ≈ 750 Ah @ 12V — beyond any realistic battery bank |
| 50% (hot day) | ≈ 18,000 Wh | A 3,600 W generator running ≈5 h/day + shore-style loads |
| 100% (extreme) | ≈ 36,000 Wh | Continuous shore power or large genset |
This is the arithmetic behind every "can I boondock with AC?" forum war: the answer is battery chemistry doesn't scale to 18 kWh/day — solar the size of a small roof won't either. AC budgeting is generator/shore budgeting.
Turning budgets into equipment decisions
- Battery: baseline + furnace nights ÷ usable fraction → bank size. The runtime calculator does this per-load.
- Solar: daily Wh ÷ (sun hours × 0.75) → panel watts. See the solar calculator.
- Generator: driven by the biggest start surge (the AC), not the daily average. See the generator calculator.
- Propane: driven by burner hours. See the propane calculator.