EXECUTIVE SUMMARY

Envision Energy, a green technology company headquartered in Shanghai, China, and European renewable energy producer Kallista Energy have commenced construction of the 193 MW / 386 MWh Neuilly-en-Thelle Battery Energy Storage System (BESS) in Hauts-de-France, France. Construction began in early July 2026, with commercial operation scheduled before spring 2028. The project represents the companies' second battery energy storage collaboration in France following the Saleux BESS project, which entered construction in 2025.

Under the project, Envision Energy will supply its battery energy storage solution and manage the system throughout its lifecycle, including operation, maintenance and end-of-life battery recycling after an expected 25 years of service. The battery system will use lithium iron phosphate (LFP) cells manufactured by Envision AESC. The cells are supplied from the company's 10 GWh battery gigafactory in Hauts-de-France, which has been operational since June 2025, supporting local battery manufacturing and system integration.

Once commissioned, the Neuilly-en-Thelle BESS will provide flexibility services to the French electricity grid, including frequency regulation through reserve markets operated by transmission system operator RTE. The storage facility is designed to help balance electricity supply and demand, improve grid stability, and facilitate the integration of higher shares of renewable energy into the power system.

According to Envision Energy, the storage capacity is equivalent to the daily electricity consumption of approximately 30,000 households. The project is intended to support France's ongoing electrification efforts while strengthening regional energy infrastructure.

According to him, the company's second BESS project with Kallista Energy reflects the continued growth of their partnership based on shared ambitions for Europe's energy transition and supports the Future Energy System by strengthening grid resilience, accelerating renewable energy integration and contributing to sustainable industrial development across Europe.

The Neuilly-en-Thelle project expands Envision Energy's presence in the European battery energy storage market while reinforcing its partnership with Kallista Energy. The project also demonstrates the increasing deployment of utility-scale battery storage systems to provide balancing services, improve renewable energy integration and enhance electricity network flexibility across France.