Tesla Powerwall 3 vs Fox ESS EP11 Battery Storage is a key comparison for Australian homeowners looking to reduce electricity bills and increase solar self-consumption. Tesla Powerwall 3 offers 13.5 kWh of usable storage, a built-in solar inverter, and powerful whole-home backup during blackouts. The Fox ESS EP11 provides 10.36 kWh of usable capacity, flexible expansion options, and a lower upfront cost.
Both batteries use safe lithium iron phosphate (LFP) technology and store excess solar energy for use at night. However, they differ in power output, backup capabilities, installation requirements, and overall value. This guide allows you to compare capacity, performance, price, backup power, warranty details, and the real-world value of battery options for your home here in Australia.
Powerwall 3 vs EP11 Battery Storage in Australia – Quick Comparison
| Feature | Tesla Powerwall 3 | Fox ESS EP11 |
| System Type | All-in-one (integrated hybrid inverter) | Dedicated DC storage battery (requires external Fox hybrid inverter) |
| Nominal Capacity | 13.5 kWh | 10.36 kWh |
| Usable Capacity | 13.5 kWh (100% DoD) | ~9.32 kWh (90% DoD) |
| Continuous Output | Up to 11.5 kW | Dependent on the paired Fox inverter (typically 5 kW to 10 kW) |
| Battery Chemistry | Lithium Iron Phosphate (LFP) | Lithium Iron Phosphate (LFP) |
| Scalability | Up to 4 units (max 54 kWh total) | Up to 4 units in parallel (max 41.6 kWh total) |
| Efficiency | Up to 97.5% round-trip | ≥ 95% round-trip |
| Weather Rating | IP67 (highly flood/dust resistant) | IP65 (outdoor safe) |
| Warranty | 10 years (unlimited cycles, 70% retention) | 10 years (standard capacity retention guarantee) |
| App Ecosystem | Tesla Mobile App (includes advanced Storm Watch feature) | Fox Cloud 2 App (includes dedicated web monitoring portal) |
What Is Tesla Powerwall 3?
The Tesla Powerwall 3 is a home battery storage system that stores extra solar energy power for use at night, when the sun has gone down, during breakdowns, or simply during high electricity prices. The system, with a high-capacity lithium cell and an integrated solar inverter, is designed to be stored tightly on 1 unit, resulting in simplified installation.
3-phase Tesla Powerwall is capable of delivering the energy where it is needed, either for appliances like a fridge and TV or the entire home. It also interfaces with the Tesla app, enabling homeowners to track energy production, storage, and consumption in real-time. The third-generation Powerwall is for new solar installations with optional expansions by connecting to additional battery units.
Key Specifications
- Battery Capacity: 13.5 kWh
- Continuous Power Output: Up to 11.5 kW
- Built-in Hybrid Solar Inverter
- Up to 4 Powerwall 3 units supported
- 10-Year Manufacturer Warranty
- Indoor and Outdoor Installation
- Tesla App Monitoring and Smart Controls
- Backup Power During Grid Outages
- Solar-to-Grid Efficiency: Up to 97.5% (energylibrary.tesla.com)
Best Use For
- Homes with solar panels
- Large households with high electricity use
- Homeowners wanting backup power during blackouts
- EV owners charging electric vehicles at home
- Households looking to reduce electricity bills
- People who want smart energy management and monitoring (Tesla)
What Is EP11 Fox ESS Battery Storage?
The Fox ESS EP11 is a residential lithium iron phosphate (LFP) battery designed to store excess solar energy for use at night or during power outages. It is a modular battery system that works with compatible Fox ESS hybrid inverters, helping homeowners reduce their use of grid electricity and lower their energy bills.
Key Specifications
- Usable Capacity: 10.36 kWh
- Battery Type: Lithium Iron Phosphate (LFP)
- Nominal Voltage: 403.2V
- Depth of Discharge (DoD): 90%+
- Round-Trip Efficiency: Up to 95%
- Warranty: 10 Years
- Scalability: Up to 4 batteries can be connected
- Installation: Floor-mounted design
- Monitoring: FoxCloud smart monitoring platform
- Backup Power: Available with compatible inverter setup
Best Use For
- Homes with a 5 kW–10 kW solar system
- Homeowners looking for affordable battery storage
- Reducing electricity bills through solar self-consumption
- Storing excess daytime solar energy for evening use
- Homes with moderate daily energy consumption
- Users who want the option to expand battery capacity later
Real Life Performance Comparison: Tesla Powerwall 3 vs. EP11 Fox ESS Battery
The Tesla Powerwall 3 delivers better overall performance for large homes and backup power, while the Fox ESS EP11 provides reliable energy storage at a lower cost. In daily use, both batteries help reduce electricity bills by storing excess solar energy for use at night.
Power and Capacity
Tesla Powerwall 3 offers 13.5 kWh usable capacity and up to 11.5 kW continuous power output. This allows it to run multiple high-power appliances at the same time, including air conditioners, ovens, and EV chargers.
Fox ESS EP11 provides 10.36 kWh usable capacity and is designed for homes with moderate energy use. It can easily power lighting, refrigerators, televisions, and other everyday appliances.
Real-Life Example
A family in Australia with a 10 kW solar system and an electric vehicle can often operate most household appliances overnight using a single Powerwall 3. During a blackout, the battery can keep the entire home running.
With an EP11 system, a similar family can cover evening energy needs and maintain essential appliances during outages, but heavy loads may require additional battery modules.
Customer Feedback
Powerwall 3 owners often praise:
- Fast backup switching during outages
- Easy-to-use Tesla app
- Strong performance with large household loads
Fox ESS EP11 users commonly highlight:
- Good value for money
- Reliable daily solar storage
- Flexible expansion options
Some users note that Tesla’s software experience is more polished, while Fox ESS offers better affordability.
Cost Comparison: Powerwall 3 vs. EP11 Battery Storage
The Tesla Powerwall 3 offers superior all-in-one value for whole-home backup due to its higher continuous output (11 kW) and massive built-in hybrid inverter, despite its higher $13,500–$17,000 upfront price tag.
Conversely, the Fox ESS EP11 provides a lower entry point at approximately $8,000–$10,000 (excluding an external hybrid inverter), making it the more flexible, budget-friendly option for modular expansions up to 41.6 kWh.
Side-by-Side Comparison (With Inverter Costs)
| Feature / Metric | Tesla Powerwall 3 | Fox ESS EP11 |
| Estimated Installed Cost (AUD) | $13,500 – $17,000 | $8,000 – $10,000 (battery unit only) |
| Inverter Included | Yes (Built-in 11.2 kW Hybrid Inverter) | No (Requires external unit) |
| Additional Inverter Cost | $0 (Fully integrated) | $2,500 – $4,500 (Depending on size/phases) |
| Calculated Cost per Usable kWh | ~$1,000 – $1,250 / kWh | ~$860 – $1,070 / kWh (excluding inverter) |
| Continuous Power Output | 11.2 kW | Dependent on paired external inverter |
| System Scalability | Up to 4 units (54 kWh total) | Up to 4 units in parallel (41.44 kWh total) |
| Round-Trip Efficiency | 97.5% | ≥95.0% |
| Thermal & Safety Management | Liquid thermal management | Built-in fire suppression & self-heating tech |
| Standard Warranty | 10 years | 10 years |
Which Battery Should You Choose? Tesla Powerwall 3 vs. EP11 Fox ESS Battery
The right choice depends on your budget, energy usage, and backup power needs. Choose Tesla Powerwall 3 for maximum performance and blackout protection. Choose EP11 Fox ESS solar battery for lower upfront cost and strong everyday solar savings.
For more details, watch our comparison video on Tesla Powerwall 3 vs Fox ESS :
Choose Tesla Powerwall 3 If:
- You want whole-home backup during power outages.
- You have high-energy appliances such as air conditioners, pool pumps, or EV chargers.
- You prefer an all-in-one battery with a built-in inverter.
- You want advanced monitoring through the Tesla app.
- You plan to expand your solar and battery system in the future.
Tesla Powerwall 3 is best for large households that need high power output and seamless backup performance.
Choose Fox ESS EP11 If:
- You want a more affordable battery system.
- Your home has moderate daily electricity consumption.
- You already have or plan to install a compatible hybrid inverter.
- You want flexible battery expansion at a lower cost.
- Your main goal is reducing electricity bills with stored solar energy.
EP11 Fox ESS Australia is ideal for homeowners looking for reliable battery storage without paying a premium price.
Final words
In the Tesla Powerwall 3 vs EP11 Fox ESS Battery Storage comparison, both batteries provide reliable solar energy storage and help reduce electricity costs. Tesla Powerwall 3 is the better choice for homeowners who want higher power output, seamless whole-home backup, and a premium all-in-one system with a built-in inverter. The Fox ESS EP11 stands out for its lower upfront cost, flexible expansion options, and strong value for money.
For large homes with high energy demands, Tesla Powerwall 3 offers superior performance. For budget-conscious homeowners focused on maximizing solar savings, the EP11 is an excellent alternative. The best choice depends on your budget, energy usage, and backup power requirements.
FAQs on Tesla Powerwall 3 vs Fox ESS EP11
Can Fox ESS provide backup power?
Yes. Fox ESS can provide backup power when installed with compatible inverters and backup systems. Backup performance depends on system design and battery capacity.
Which battery is easier to install?
Tesla Powerwall 3 is usually easier to install because it includes a built-in hybrid inverter. This reduces system complexity and minimizes additional equipment requirements.
Which battery offers more capacity options?
Fox ESS offers more capacity choices. Homeowners can select smaller or larger battery sizes and expand storage later as energy demands increase over time.
What is the warranty for Tesla Powerwall 3?
Tesla Powerwall 3 comes with a 10-year manufacturer’s warranty. The warranty guarantees battery performance and energy retention under normal operating conditions.
What is the warranty for Fox ESS batteries?
Most Fox ESS battery systems include a 10-year manufacturer’s warranty. Coverage varies by model but generally provides long-term protection for residential installations.
