Short answer: 200 W covers lights, fans and phones; 400 W is the most common van build for a 12 V fridge, laptop work and Starlink; 600 W+ if you run an induction cooktop or work full days on battery.
| Kit | Daily output at 4.5 sun hrs (75%) | Typical battery | Fits |
|---|---|---|---|
| 200 W | ~675 Wh | 100 Ah LiFePO4 | weekender: lights, fan, phone |
| 400 W | ~1350 Wh | 200 Ah LiFePO4 | fridge + laptop + Starlink Mini |
| 600 W | ~2025 Wh | 300–400 Ah LiFePO4 | full-time remote work, small induction use |
Roof space: a 100 W rigid panel is roughly 40 × 20 in; check your van's usable roof around fans and racks. Get the details for your loads with the daily energy calculator and solar size calculator. Kits typically include panels, an MPPT controller, mounting and cables; batteries and fusing are often extra.
Safety: These are general estimates, not a design. Follow your equipment manufacturer's instructions and local electrical code, and consult a qualified electrician for anything connected to shore power, a house, or high-current batteries.
For most van builds with a 12 V fridge, lights, fans, a laptop and Starlink Mini, 400 W and 200 Ah of lithium works in sunny seasons.
It's common: an alternator DC-DC charger fills the battery while driving, which helps a lot in winter and cloudy weather.
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