Solar battery prices are $6,000 to $13,000 on average or $600 to $1,000 per kWh for the unit alone, depending on the capacity, type, and brand. Batteries with more than 25 kWh capacity for whole-house backup can exceed $25,000, not including installation. How much does the Franklin Home Power system cost? Fully installed, the average price of the Franklin Home Power system (one aPower + one aGate controller) is around $18,000. After claiming the 30% federal clean energy credit* on your taxes, the net cost comes down to $12,600. Picture this: The grid goes down during a summer storm, but your lights stay on, your fridge keeps humming, and your WiFi never skips a beat. That's the promise of solar batteries —but at nearly $11,000. Solar battery costs vary by brand and capacity, and there are several other expenses associated with home energy storage. Depends on battery type (LiFePO₄ or NMC) and capacity (kWh). Inverter: Converts DC to AC, about 10%–20% of the price.