Battery Sizing Calculator
How big a battery do you actually need? Enter your total load in watts and the backup hours you want, pick your system voltage and battery type, and get the required Ah plus how many standard batteries that means — instantly.
Note: connecting batteries in series increases voltage, connecting in parallel increases Ah. Match the combination to your inverter's voltage.
How to use
- Enter your total load (W) and how many hours of backup you need.
- Select the system voltage and battery type — DoD (depth of discharge) is applied automatically.
- The required Ah and the number of 200Ah / 100Ah batteries appear instantly.
Tips
- Size from your actual measured load, not the sum of nameplates — not everything runs at once.
- Lithium batteries allow deeper discharge than lead-acid, so you need fewer of them.
- Add a 15–20% safety margin for ageing and cloudy days.
- DoD (depth of discharge) is applied automatically when you pick a battery type.
Formula: Required Ah = (Load × Hours) ÷ (Voltage × DoD × Efficiency). For battery sizing or solar installation: Azlaan Electric AC Solar Center, Faisalabad — 0300-8987448.
Frequently Asked Questions (FAQ)
What does the Battery Sizing Calculator do?
It finds how big a battery you need for your load and backup hours, and how many 100Ah or 200Ah batteries to buy, for UPS and solar systems.
What do I need to enter?
Your total load in watts, the backup hours you want, the system voltage, the battery type, and the inverter efficiency.
What formula does it use?
Required Ah equals load times hours, divided by voltage times depth of discharge times efficiency.
Should batteries be connected in series or parallel?
Connecting batteries in series increases voltage, connecting in parallel increases Ah. Match the combination to your inverter voltage.
Does it tell me how many batteries to buy?
Yes. It shows the required Ah and how many standard batteries that means.