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Fortress Power Envy Duo 21 48V Hybrid Solar Inverter
$4,898.00 USD
Pickup available at Shop location
Usually ready in 2 hours
The Fortress Power Envy Duo 21 is Fortress Power's most powerful 48V hybrid inverter, built to handle both residential and light commercial energy needs. With up to 25kW of solar input and dual-phase support (240V split-phase and 208V three-phase), it delivers a reliable 12kW of continuous backup power with up to 16kW export capacity.
Perfectly paired with Fortress Power's 48V batteries, the Envy Duo 21 offers flexible applications from whole-home backup to off-grid living. With built-in AC/DC breakers, rapid shutdown transmitter, and scalability up to 120kW by connecting up to 10 units in parallel, it's a future-ready solution designed for maximum performance and long-term reliability.
Key Features
- High PV Input, Maximum Generation - Handles up to 25kW of solar input, so you can generate more solar production and store more energy from your system - perfect for larger homes or small businesses.
- Flexible Voltage for Any Setup - Works with both 240V split-phase and 208V three-phase setups, giving you compatibility across different grid types without extra equipment.
- Streamlined Battery Integration - Optimized for Fortress Power 48V batteries, delivering 12kW continuous output and up to 16kW peak, ensuring whole-home or business backup without compromise.
- Expandable as You Grow - Expand your system by connecting up to 10 inverters in parallel, allowing your energy capacity to grow as your needs increase - without a full redesign.
Pairs well with: Fortress Power eForce, eVault MAX, and eFlex MAX batteries
Have any questions? Email us at info@solwel.com or give us a call at (346) 432-4228.
Why Buy From Solwel?
- Free Shipping on Orders Over $10,000 - Fast fulfillment from our Houston and Dallas warehouses
- Authorized Distributor - Genuine manufacturer-backed products with full warranty support
- Expert Technical Support - Our team knows these products inside and out. Call us at (346) 432-4228
- Installer Pricing Available - Contact us for volume pricing and contractor accounts
- Stocked in Texas - Reduced lead times for Southwest and national projects
Frequently Asked Questions
What is the maximum solar input for the Envy Duo 21?
The Envy Duo 21 supports up to 25kW of solar PV input, making it well-suited for larger residential arrays and light commercial installations where maximum generation is a priority.
What voltage configurations does it support?
The Envy Duo 21 supports both 240V split-phase (standard U.S. residential) and 208V three-phase configurations, giving it broad compatibility across residential and light commercial grid types without additional equipment.
Can I scale up beyond one unit?
Yes - you can connect up to 10 Envy Duo 21 units in parallel for a total system capacity of up to 120kW, making it a strong fit for growing energy needs or light commercial properties.
What batteries are compatible with the Envy Duo 21?
The Envy Duo 21 is optimized for Fortress Power 48V batteries, including the eForce, eVault MAX, and eFlex MAX. Contact us at (346) 432-4228 for questions about third-party battery compatibility.
Does Solwel offer installation support?
Solwel is a solar equipment distributor, not an installation company. However, we can connect you with certified local installers in the Houston and Dallas area. Call us at (346) 432-4228 or email info@solwel.com.