Power Your Future: The Fortress Power Envy Duo 21 All-in-One Inverter

Take full command of your energy with the Fortress Power Envy Duo 21 Inverter, the all-in-one 48V hybrid solution designed to meet the demands of modern residential and light commercial solar systems. This isn't just an inverter; it's the smart, scalable heart of your energy ecosystem. It's the perfect choice for DIY enthusiasts, professional installers, and homeowners in areas with high electricity rates or a need for reliable backup power. The Fortress Power Envy Duo 21 is engineered for peak performance and built to simplify your path to energy independence, no matter the scale of your project.

Key Features

High PV Input Capacity: The Fortress Power Envy Duo 21 accepts up to 25kW of PV input, making it ideal for large residential or light commercial solar arrays seeking maximum generation potential. This allows you to connect to a large solar array to generate and store more electricity, maximizing your return on investment and ensuring power for high-demand applications.
Dual Voltage Compatibility: This inverter supports both 240V split-phase and 208V three-phase applications, making it incredibly flexible for a wide range of grid configurations. This versatility is a key advantage for professional installers and allows for use in diverse residential and commercial settings.
Seamless Battery Integration: The Fortress Power Envy Duo 21kw is perfectly paired with Fortress Power 48V batteries to deliver a stable 12kW of continuous power with a max up to 16kW. This ensures reliable, whole-home or light commercial backup power, providing peace of mind during grid outages.
Scalable System Design: With the ability to parallel up to 10 units for a total output of 120kW, the Fortress Power Envy Duo 21 allows you to expand your system as your energy demands grow. This modular design eliminates the need for a complete system redesign, protecting your initial investment.
Integrated Install-Friendly Hardware: The unit includes built-in AC and DC breakers, and an integrated rapid shutdown transmitter for faster, code-compliant installations. This feature simplifies wiring, reduces installation time, and ensures your system meets the latest safety regulations, including NEC requirements.
Remote Monitoring and Firmware Updates: Monitor your solar production, battery performance, and grid consumption from anywhere via the Fortress Power Mobile App. The Fortress Power Envy 21 also supports remote firmware updates, ensuring your system stays up-to-date with the latest features without the need for an on-site visit.

Safety and Code Compliance: A Foundation of Reliability

Safety is a paramount concern for any solar installation, and the Envy Duo 21 is built with this in mind. It is certified to meet rigorous safety and grid-compliance standards, including UL 1741-SA and IEEE 1547. These certifications ensure the inverter's reliability and safe operation in a grid-connected environment. The integrated rapid shutdown transmitter is a critical component for fire and electrical safety, as required by modern electrical codes. The robust enclosure is rated NEMA4X / IP66, meaning it is highly resistant to dust, water, and corrosion, making it suitable for both indoor and outdoor installations in challenging environments. With features like Arc Fault Circuit Interruption (AFCI), the Fortress Power Envy Duo 21 actively protects against electrical fire hazards, giving you complete peace of mind. For homeowners and installers, this comprehensive safety framework ensures your system is not only high-performing but also fully compliant and secure.

Whether you're looking to reduce your utility bills, achieve energy independence, or prepare for power outages, the Fortress Power Envy Duo 21 is the professional-grade solution that delivers. Its high-capacity performance, scalable design, and advanced features make it the smart choice for anyone serious about solar and energy storage.

Technical Downloads

Fortress Power Envy Duo 21kW Inverter: The Ultimate Solar Power Solution | Solamp

The Fortress Power Envy Duo 21kW hybrid inverter is a powerful and versatile solar inverter designed to provide seamless battery integration, high PV input, and remote monitoring, making it the ideal solution for homeowners and businesses seeking reliable solar power and battery backup.

Unleash the Power of the Fortress Power Envy Duo 21kW

The Fortress Power Envy Duo 21kW is not just an inverter; it's a comprehensive energy management system. As a hybrid inverter, it combines the functionality of a traditional string inverter with the ability to seamlessly integrate with 48V batteries, creating a robust solar energy system for both on-grid and off-grid applications. Whether you're looking to reduce your carbon footprint, save money on your electricity bills, or ensure uninterrupted power during outages, the Envy Duo 21kW delivers unparalleled performance and reliability.

Key Features and Benefits

High Power Output: The 21kW inverter capacity is suitable for powering large homes and even light commercial businesses.
Seamless Battery Integration: Designed to work flawlessly with Fortress Power batteries, providing reliable whole home backup power when you need it most.
High PV Input: Accepts up to 25kW of PV input, maximizing your solar power generation potential and allowing you to harness the full power of the sun.
Remote Monitoring: Stay informed about your system's performance with the intuitive Fortress Power mobile app, allowing you to monitor production, consumption, and battery status from anywhere.
Scalable System Design: Parallel up to 10 units for larger power requirements or future expansion of your solar energy system.
Versatile Application: Suitable for both 240V split-phase and 208V three-phase configurations, making it adaptable to a wide range of residential and commercial settings.

Why Choose the Fortress Power Envy Duo 21kW from Solamp?

At Solamp, we are committed to providing our customers with the highest quality renewable energy solutions. The Fortress Power Envy Duo 21kW embodies this commitment, offering exceptional performance, reliability, and value. When you purchase your inverter from Solamp, you benefit from:

Expert Advice: Our team of Solar Energy Professionals can help you design the perfect system to meet your specific needs.
Competitive Pricing: We offer competitive prices on all our products, ensuring you get the best value for your investment.
Technical Support: Our knowledgeable support team is available to answer your questions and provide assistance with installation and maintenance.
Fast Shipping: We ship your order quickly and efficiently, so you can start enjoying the benefits of solar power as soon as possible.

Ideal for Off-Grid Living and Emergency Backup

The Fortress Power Envy Duo 21kW is an excellent choice for those seeking off-grid living or reliable emergency battery backup. With its seamless battery integration and robust design, this inverter can provide you with the power you need to live independently or weather unexpected power outages. Say goodbye to worrying about grid dependency and hello to energy self-sufficiency.

Technical Downloads

Data Sheet

Installation Manual

Warranty Information (Coming Soon!)

Certifications (Coming Soon)

Charge Controller Accessories

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