Battery Backup Sizing Calculator
Select the appliances you want to power during an outage and your backup duration goal. We'll calculate how much battery capacity you need and which systems are a good fit.
Estimate only. This calculator provides a general sizing estimate based on typical appliance loads. Actual battery requirements depend on your specific equipment, usage patterns, and installation design. A professional assessment is required for accurate sizing.
1. What is your primary goal?
2. How long do you want backup power?
3. Do you have existing solar?
4. Select appliances to power
Select everything you want to run during an outage. Essential loads are pre-selected.
Essential
Comfort
High-Draw
Your Estimate
Estimated Energy Needed
3.4 kWh
Includes 20% buffer for losses
Peak Load
0.4 kW
Simultaneous draw from selected loads
Daily Solar Available to Store
20.0 kWh
~60% of daily production (Fresno avg.)
Recommended System
3× Enphase IQ Battery 5P
15 kWh usable / 11.52 kW continuous
Best for: Enphase solar systems, modular expansion
(559) 355-1025
Battery Systems We Install
We install all major battery brands and help you choose the right system for your home and budget.
| System | Usable Capacity | Continuous Power | Best For |
|---|---|---|---|
| Enphase IQ Battery 5P | 5 kWh | 3.84 kW | Essential loads, smaller homes |
| Tesla Powerwall 3 | 13.5 kWh | 11.5 kW | Most homes, whole-home backup |
| Franklin aPower 2 | 13.6 kWh | 10 kW | Most homes, whole-home backup |
| 2× Tesla Powerwall 3 | 27 kWh | 23 kW | Large homes, extended outages, EV charging |
| 3× Enphase IQ Battery 5P | 15 kWh | 11.52 kW | Enphase solar systems, modular expansion |
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We size and install battery systems throughout Fresno & Madera County.
Tesla Powerwall, Enphase IQ, Franklin WH. License #1063682.