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Fortress Power

Fortress Power Solo 6.5kW Hybrid Inverter

SKU: OffGrid 6500 Inverter-STD

$1780.46

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OffGrid 6500 Inverter-STD

$1780.46

Product Overview

The Fortress Power Solo 6.5kW is a hybrid inverter that integrates solar, battery, and grid or generator power into a single unit. With a built-in 140A solar charge controller and support for both grid-tied and off-grid operation, it provides a flexible foundation for residential energy systems.

Key Features

Built-In 140A Charge Controller: Efficiently captures and converts solar energy without an external charge controller
Grid-Tied & Off-Grid: Functions as a grid-tie inverter with battery backup or a standalone off-grid inverter
Seamless Backup: Automatically switches to battery power during grid outages for uninterrupted operation
Time-of-Use Optimization: Schedule charge and discharge cycles to minimize peak-hour electricity costs
Scalable to 39kW: Parallel up to six units for larger homes, small businesses, or microgrid installations
Safety Monitoring: Optional current transformers (CTs) for precise load control and overload protection
5-Year Warranty: Included with every unit

Compatibility

Pairs with Fortress Power eBoost and eFlex MAX batteries for a balanced whole-home system. Suitable for home energy storage, off-grid cabins, backup power, and DIY solar projects.

Who Is This For?

A strong fit for homeowners building their first solar system, off-grid and cabin applications, DIY enthusiasts looking for an approachable hybrid inverter, and anyone who needs reliable backup with room to scale.

Product Documents

Spec Sheets

fp-datasheet-solo_0126.pdf

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Manuals & Guides

Solo65K_Installation_Manual_CR2025.pdf

Download

Frequently Asked Questions

Is 6.5kW enough to power my home during an outage?+

A 6.5kW inverter can run essential loads including refrigerator, lights, Wi-Fi router, and a few outlets simultaneously. For whole-home backup including AC and large appliances, consider the Envy 8kW/10kW or Envy True 12kW.

What makes the Solo a good entry-level inverter?+

The Solo offers hybrid grid-tied and backup capability at a lower cost point than higher-wattage models, making it ideal for homeowners starting with a smaller solar array who want battery backup without overspending.

Can I upgrade from the Solo to a larger inverter later?+

Yes. The Solo uses the same Fortress Power battery ecosystem, so if you outgrow the 6.5kW capacity, you can upgrade your inverter while keeping your existing batteries and solar panels.

Does the Solo support time-of-use rate optimization?+

Yes. The Solo's hybrid mode lets you store solar energy during the day and discharge batteries during expensive peak utility hours, reducing your electric bill through smart time-of-use arbitrage.

Ready to order?

Request Quote 978-451-6890