Solar, Battery & EV Power Calculator
Size a setup for your appliances, or check how much emergency range a power station can add to your electric vehicle. We do the math and match you to the best gear.
1. What do you want to power?
Enter watts and hours/day for each device. Not sure? Use the dropdown for typical values.
2. Your situation
How the math works (and our assumptions)
- Daily energy = Σ (watts × hours) for every device.
- Battery needed = daily energy ÷ 85% inverter efficiency ÷ 85% usable target × days of backup × safety margin.
- Solar needed = daily energy ÷ (70% real-world solar efficiency × your peak sun hours) × safety margin.
- Safety margin pads for cloudy days, battery aging and heavier-than-planned use. Off-grid pros size for the worst-sun month.
- Surge matters: motors (fridges, pumps, AC) spike 2–3× on startup. We make sure the station's continuous output clears your biggest single device.
1. Which EV?
We'll estimate how much driving range a portable power station can add in an emergency.
Can a power station really charge an EV?
Short answer: for emergencies, yes — but only a little. A big power station holds 1–4 kWh; an EV battery holds 60–200 kWh. So you're adding tens of miles to get to a real charger, not filling the tank.
- Energy needed = miles ÷ your EV's efficiency (mi/kWh) ÷ 85% charging losses.
- You need a station with a 1,500W+ output to run a portable Level 1 EV charger at all.
- Efficient cars (Tesla Model 3 ~4 mi/kWh) get far more range per kWh than heavy trucks (Cybertruck/Lightning ~1.6–1.9 mi/kWh).
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Recommended power stations
Need more capacity? Package options
For this much energy, an expandable unit with add-on batteries — or a DIY battery bank + inverter — is often better value than one big all-in-one.
Matched solar panels
Estimates only — verify specs before buying. Some links are affiliate links; see our disclosure.