Fortress Power Envy 8kW and 3 - eFlex 5.4kWh

$12,876.00 $11,404.00 Save $1,472.00
Envy8KW3
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The Fortress Power Envy 8kW with 3x eFlex 5.4kWh batteries is a complete solar storage solution for your entire home. Generate clean solar energy during the day, store it in the eFlex batteries, and use it to power your home at night or during outages.

Features:

  • 8kW continuous power output, expandable with additional batteries
  • 16.2kWh total usable battery storage capacity (3x eFlex 5.4kWh)
  • Works with existing solar panel system (up to 13kW)
  • Backs up your entire home during power outages
  • 90A AC pass-through for grid or generator connection
  • Dual MPPT solar inputs for maximum efficiency
  • Built-in rapid shutdown and safety features
  • Monitor and control your system remotely

Benefits:

  • Peace of mind: Never be without power during outages.
  • Energy independence: Reduce reliance on the grid and save on electricity bills.
  • Increased solar savings: Store excess solar energy for later use.
  • Scalable solution: Add more batteries as your needs grow.
  • Safe and reliable: Lithium Iron Phosphate (LFP) batteries offer long lifespan and durability.
  • Easy to manage: Monitor and control your system from anywhere.

Specifications:

  • Inverter Power Output: 8kW continuous, 12kW peak
  • Battery Capacity: 3x eFlex 5.4kWh (total 16.2kWh)
  • Battery Chemistry: Lithium Iron Phosphate (LFP)
  • AC Input Voltage: 120/240V
  • AC Output Voltage: 120/240V
  • MPPT Inputs: 2
  • Maximum Solar Input: 13kW

Get a Fortress Power Envy 8kW with 3x eFlex 5.4kWh batteries today and experience the power of solar energy independence!

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Fortress Power

"Serious storage capacity and quality with an accessible price tag."

Chris S.

"Great company with a knowledgeable and extremely helpful staff!"

Nick K.

"I installed four batteries and am very happy with all four. The customer support was excellent, they were very easy to work with."

William Jennings

"Had an odd error from eVault Max. Emailed support and they wanted to do firmware update. They had to ship out an adapter but I had tracking info in 90 minutes and they were great to work with. They even took the time to double check the settings in my inverter. It wasn't cheap, but thus far I'm quite happy with the company."

David N.

"I have been in the biz for 38 yrs. The past 15 yrs installing in the Caribbean region of USVI and Puerto Rico. Every residential client has the Fortress Power battery as their ESS. We even have a few light commercial systems using the eVaults with perfect results. We have systems as big as 6 eVaults on 3 Sol-Ark's, down to two 5kW paralleled on back-up systems. The BMS systems make these batteries, hands down the best choice for our clients. I have used many different LPF over the years. None have compared to what we are getting with Fortress. We pay .43kWh, so all our systems are set up as self consumption. That means we need a battery that will handle the loads and handle the environment. Fortress batteries always comes through. I also am very confident in the technical staff. Jing and Eric can answer all my complex technical questions. My company has been installing these batteries going on two years now. I only have happy customers. It is great dealing with a professional company like Fortress. Keep up the great work!!!"

Michael B.

"We have done quite a bit of business with Fortress Power, and they are very friendly, knowledgeable, and easy to work with."

Jason J.

FAQ

View frequently asked questions for Fortress Power Products. Any questions not answered here, contact us by email, chat, or by phone: 1 (302) 244-7703

Does energy storage work well with my solar system?

Yes. On the grid? Absolutely! Energy storage adds a lot of value to your solar systems. It keeps your solar system operating when your utility service is interrupted. Without energy storage, your PV system will be forced to shutdown when the grid is off.

If you live off grid, energy storage enables you to use the clean solar energy to power your home day and night.

Fortress Power also knows you’re a fan of conservation—energy storage saves both your surplus solar energy and your cash since it reduces on grid energy dependence.
Can I use energy storage without solar panels?

Absolutely. For on grid clients, a home energy storage unit  stores energy from your electricity provider. If an outage occurs, home energy storage can provide up to 24 hours of potentially life-saving power. Need more reassurance? Fortress Power offers batteries with larger storage capabilities, completely customizable to your needs. And, like you, we appreciate saving money. When electricity is at its lowest daily rate, our smart energy storage units use that period to charge. When peak electric use occurs, our energy storage units can discharge power to suit your lifestyle.
What about power outage protection?

Power interruptions shouldn’t disrupt your schedule. An energy storage system will keep your solar system operating during grid outages. When paired with solar panels, an energy storage system supplies unlimited energy delivery. The solar panels power your home during the day and use any excess power to charge the battery. At night, the system keeps your space bright. When used without solar panels, power outage support is dependent on battery size and your energy use. Batteries providing at least 12 hours of backup power are safest.
Are home energy storage systems financially beneficial?

You can use the energy storage to shelve your peak usage. When electricity is at its lowest daily rate, our smart energy storage uses that period to charge. During the peak periods, our energy storage system can power your home, reducing your electricity bill. Clients with solar panel installations enjoy a faster return on investment.
What is Lithium batteries lifespan?

We provide a 10 year product warranty and guarantee up-to 6000 cycles, whichever comes first. Speak to our representatives for details.
Why choose Lithium Iron Phosphate over Lithium Ion batteries?

We use Lithium Iron Phosphate (LiFePo4; Lithium Ferro Phosphate) technology – the safest lithium technology in the industry. It’s environmentally friendly and can be fully recycled. While Many other competitors, such as LG Chem, Tesla and Panasonic use cobalt-based Lithium-Ion battery, which has a very poor thermal stability. Any short circuit or cell-breakage can cause thermal runaway and catch fire.

And comparatively, Lithium Iron Phosphate battery deliver substantially higher amount of life cycles. We guarantee up-to 6000 cycles, while LG Chem, Tesla and Panasonic provide less than 3000 cycles.
Are Fortress Lithium batteries widely compatible?

Yes, our batteries are designed to work with all 48V chargers and hybrid inverters. We work well with Schneider, Outback, Magnum, Sol-Ark, Victron, Morningstar and so on. Please Check out this Inverter Compatibility list.

Fortress Power

Fortress Power

Fortress Power is a company that designs, manufactures, and sells lithium iron phosphate (LFP) batteries for energy storage applications. Their batteries are known for being safe, long-lasting, affordable, and easy to install and maintain. Fortress Power batteries can be used for a variety of applications, including backup power, time-of-use, self-consumption, and off-grid.
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