10 Best Stem Alternatives & Competitors (2026)

Fluence delivers grid-scale energy storage systems with integrated software for asset optimization and market participation. Its strengths include turnkey hardware-software bundles and global project experience, but it focuses more on full EPC delivery than Zitara's narrow on-premise signal correction. Pricing is typically project-based and higher for complete systems; it suits operators wanting end-to-end solutions rather than bolt-on BMS improvements.

Fluence delivers grid-scale energy storage systems with integrated software for asset optimization and market participation. Its strengths include turnkey hardware-software bundles and global project experience, but it focuses more on full EPC delivery than Zitara's narrow on-premise signal correction. Pricing is typically project-based and higher for complete systems; it suits operators wanting end-to-end solutions rather than bolt-on BMS improvements.

AutoGrid offers a flexible DERMS platform for virtual power plants and battery coordination across fleets. Its cloud-native strength lies in predictive grid services and multi-asset orchestration, yet it provides less emphasis on real-time rack imbalance correction than Zitara. Pricing follows SaaS models suitable for utilities managing diverse resources beyond single-site BESS optimization.

ABB provides Ability platform analytics for energy storage with strong emphasis on predictive maintenance. It integrates well with existing electrical infrastructure but centers on general asset health rather than Zitara's trading-signal precision and balancing prioritization.

Tesla Megapack systems include integrated Autobidder software for energy trading and optimization. Strengths are vertical integration and rapid deployment, but the closed ecosystem limits customization compared with Zitara's multi-OEM compatibility. Ideal for new installations seeking simplicity rather than retrofitting existing assets with advanced balancing signals.

Wartsila supplies energy storage solutions with GEMS software for performance monitoring and lifecycle management. It excels in hybrid power plant integration and long-term service contracts but offers broader system controls instead of Zitara's targeted power and balance algorithm replacements. Suited for large infrastructure projects needing vendor-managed operations.

Sonnen focuses on residential and small commercial battery systems with community energy sharing features. Its software emphasizes ease of use and virtual power plant participation, differing from Zitara's industrial rack-level precision. Lower-cost subscription options appeal to distributed deployments rather than utility-scale trading optimization.

PowerSecure delivers microgrid and storage controls with strong emphasis on resilience and utility partnerships. It provides reliable hardware-software packages but less specialized cell modeling than Zitara. Best for critical infrastructure customers prioritizing uptime guarantees over incremental capacity unlocks.