Off Grid Solar Load Calculator
Roll up off-grid site loads into daily kWh from device watts and run hours—then size array and autonomy next.
Quick answer
Daily kWh ≈ Σ(Watts × Hours) ÷ 1000. Example: 800 W for 10 h + 200 W for 5 h → 9.0 kWh/day. Next: panel sizing. Hub: Solar calculator.
Quick Off Grid Load Calculator
Defaults: one continuous load 800 W × 10 h.
800 W × 10 h ÷ 1000.
Advanced Off Grid Load Calculator
Presets
Up to three load groups (W × h/day). Spare margin adds contingency.
Off Grid Load Results
Engineering disclaimer
Planning estimate only. Confirm nameplate watts, duty cycles, and startup surges on site before array or battery procurement.
Daily kWh by contingency
| Margin | kWh/day |
|---|
People also ask
- How do I calculate off-grid load? Sum watts × hours, divide by 1000.
- Next after daily kWh? Size the PV array, then autonomy days.
- Same as factory load? Similar roll-up, but off-grid duty cycles and no utility diversity.
Planning guidance
- Array next: Feed daily kWh into the solar panel sizing calculator. Method: how to size a commercial solar array.
- Autonomy: Size storage days with battery autonomy days—not UPS runtime tools.
- PSH: Confirm resource with peak sun hours.
- Hub: Solar calculator.
Typical scenarios
- Telecom hut: Continuous radio + intermittent cooling—watch 24 h loads.
- Remote workshop: Day-heavy tools—hours often 6–10 h, not 24.
- Hybrid site: Partial generator cover—still size PV for critical kWh first.
Formula (quick reference)
Daily kWh = Σ(W × h) ÷ 1000 × (1 + margin%)
Next funnel: how to size a commercial solar array → panel sizing.
Frequently Asked Questions
How do I calculate off-grid solar load?
Multiply each load’s watts by hours per day, sum watt-hours, divide by 1000, then apply contingency margin.
What is the difference from the factory load calculator?
Factory load targets plant demand and diversity for utility/transformer planning. This tool targets off-grid daily energy for PV and battery screens.
Should I include surge loads?
Screen continuous energy separately; motor starts need inverter/surge checks outside this daily kWh roll-up.
What is the next step?
Size the PV array from daily kWh, then screen autonomy days and MPPT current.
Is this for camping kits?
No—industrial/remote-site planning. Avoid portable power-station shopping intents.
How it works
Off-grid daily energy is the sum of watt-hour contributions from each load group, with an optional contingency margin for growth and measurement error.
Worked examples
- 800 W × 10 h + 200 W × 5 h, 15% margin
Base 9.0 kWh → with margin ≈ 10.35 kWh/day.