Solar battery profitability and Indevolt's storage solutions

The economic viability of domestic solar storage batteries is facing scrutiny due to shifting energy tariffs in France. While manufacturers often claim a return on investment within five to seven years, updated calculations based on current French regulated rates suggest a much longer period, potentially between fifteen and twenty-one years. This discrepancy is largely attributed to manufacturers using electricity price simulations of €0.34 per kWh, which is approximately 70% higher than the actual regulated rate of €0.2001 per kWh.

Profitability is further impacted by the drop in surplus electricity resale rates, which fell to 1.1 cents per kWh as of June 2026. This makes self-consumption more attractive than selling excess energy, but complicates the math for battery payback.

In response to the demand for accessible renewable energy, the company Indevolt is developing plug-and-play solar storage solutions. Their systems are designed to be stackable, compact, and easy to install for both homeowners and renters. The company aims to democratize solar self-consumption across Europe through a flexible and open system compatible with smart meters and home automation platforms.