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Solar Battery Calculator
Size a battery bank for your solar system.
Capacity (kWh) = daily consumption × autonomy days / depth of discharge. Amp-hours = kWh × 1000 / voltage.
How it works
Capacity (kWh) = daily consumption × autonomy days / depth of discharge. Amp-hours = kWh × 1000 / voltage.
Worked example
10 kWh/day × 2 days / 0.8 = 25 kWh. At 48 V that is 521 Ah.
Recommendations
- Do not discharge below 20% to protect the battery
- Lithium batteries allow deeper cycling than lead-acid
- Add 20% for aging and cold weather
Tips & advice
- Match battery voltage to your inverter
- Keep batteries in a ventilated, temperate space
- Plan for winter days of low solar production
Fuel Consumption Calculator
Find your real fuel consumption from a full tank test.
Fuel Cost Calculator
Know the cost of your trip before you leave.
Weeks Between Dates Calculator
Find out exactly how many weeks separate two dates.
Months Between Dates Calculator
Know how many months separate any two dates.
Solar Battery Calculator
Size a battery bank for your solar system.
Use the calculatorInvoice Generator FAQs
Yes, all 20 home calculators are 100% free, private and run entirely in your browser. No account needed.
They use standard industry formulas. Always round up for materials and confirm with a professional for structural work.
The calculators use metric units (meters, liters, m³). Convert imperial measurements beforehand if needed.
No. Calculations happen instantly in your browser and nothing is sent to any server.
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