Battery Calculator

Battery Sizing Calculator: How It Works

Use this battery sizing calculator to find the perfect battery size for your home backup needs. Enter your daily energy usage, solar system size (or 0 if you don't have solar), and desired backup duration to get instant recommendations.

Our battery sizing calculator helps you find the exact battery capacity needed to power your home through outages and overnight.

Essential Loads Only

If you only want to power critical appliances during an outage (refrigerator, lights, WiFi, medical devices), enter 30-40% of your total daily usage. For example, if your home uses 30 kWh/day normally, enter 10-12 kWh to size a battery for essential loads only. This significantly reduces battery cost while maintaining backup for what matters most.

What You'll Learn

• Recommended battery size - Exact kWh capacity needed for your home
• Backup duration - How long your battery will power your home
• Installation costs - Complete investment breakdown with the 30% federal tax credit
• Battery comparison - Compare Tesla Powerwall, Enphase, and LG options

Why Get Battery Storage?

Home batteries provide backup power during outages, protect against grid instability, and when paired with solar, enable true energy independence. With increasing power outages nationwide and the 30% federal tax credit available through 2032, battery storage is more affordable and valuable than ever. For more details, visit Energy.gov.