How Many B300K Battery Modules Can You Choose for Home Backup?

Power outages aren’t just inconvenient anymore — they’re becoming a real threat to daily life. Whether it’s unexpected grid failure, seasonal storms, or a push toward energy independence, more families are looking for reliable backup solutions.

That’s where Apex 300 + B300K comes in.

This modular backup system lets you start with just the basics — and scale up to whole-home backup. But one of the biggest questions we hear is:

“How many modules do I actually need?”

The answer depends on:

• What you want to keep running (Wi-Fi, fridge, lights, AC?)
• For how long (A few hours? A few days?)
• Whether you’ll be using solar, oil generator, or just charging from the wall

This guide breaks down the math and the logic. We'll look at real-life home scenarios and help you decide how many Apex 300 units (inverter modules) and B300K units (battery modules) you need — and exactly what each setup can power.

What Appliances You Need to Power

Before deciding how many modules you need, the most important question is:

What do you actually want to keep running when the power goes out?

The answer will vary depending on your home setup, lifestyle, and location. Some users only want to power a few essential items like lighting and WiFi. Others may want enough backup to run refrigerators, cooking appliances, or even the entire home including HVAC systems.

To help estimate your needs, here's a practical breakdown of typical home appliances and how much energy they consume over a day.

Common Home Appliances and Daily Power Consumption

With this table, you can start building a realistic picture of your daily energy needs. A small setup might only need 2–3kWh per day. But for full-home backup with heating, cooling, or charging, the need can quickly exceed 10kWh or more.

Next, we'll walk through what an Apex 300 and B300K can actually deliver—and how to match them to your needs.

Understand What Each Module Can Do

To build a system that matches your backup needs, it's important to understand the role of each component. The Apex 300 + B300K system is fully modular, which means you can expand both power output and energy capacity by adding more units as needed.

Load Table: Medium Backup Use Case

Runtime Estimate:

• With 2× B300K (~5.6kWh usable), this setup can support 2 full days of essential use
• Or run a heavier load profile for 1 full day (including microwave, entertainment, fan cooling)

UPS Support:

• Same as Light Backup: connect grid power to Apex 300
• Use left-side AC outlets for 0ms switch time
• Use Custom Mode to pre-schedule battery usage (eg daytime discharge, night charging)

Charge Strategy:

• Use Turbo Mode for fast recharging from generator or stable grid
• Silent Mode at night to reduce fan noise
• Grid Self-Adaption Mode recommended if using oil generator

Scalability:

• Want to cover more devices or stretch beyond 2 days? Add 1–2 more B300K units
• Want to run AC or power tools? Consider upgrading to the Heavy Backup setup with more inverter output

Heavy Backup — 2 to 3 Days or Larger Load Support

For users who want to maintain more than just essential loads during an outage — this setup supports appliances like a microwave, fan, TV, multiple laptops, or small kitchen devices, in addition to core essentials like a fridge and lighting.It's designed for people who experience full-day outages or recurring blackouts and want a system that allows daily routines to continue with minimal compromise.

Best for you if:

• You want to keep both essentials and comfort appliances running during outages
• You work from home and need to 1× Apex 300
  
• 3× or 4× B300K
  
• Optional
  
  • 2–4× 350W solar panels
    
  • Oil generator for fast recharging
    
  • B300K Hot Swap Strategy (optional expansion battery set for days 3–4)
    

Total Usable Energy:

• 3× B300K = ~8.4kWh
  
• 4× B300K = ~11.2kWh
  Output Power Available: 3,840W (continuous)
  

Load Table:Heavy Backup Use Case

Runtime Estimate:

• 3× B300K: ~2.5 days of heavy essentials
• 4× B300K: ~3 full days without needing to recharge

UPS Support:

• Fully supported — plug fridge, network,lighting into left AC ports for 0ms transfer
• App control via Custom Mode or Time Control Mode (for peak time use)
• All modes available when grid is connected; fallback to direct battery use when off-grid

Charge Strategy:

• Turbo Mode recommended for oil generator
  

• Silent Mode for nighttime charging
  

• Solar recharging can extend daily availability (350W × 4 panels = ~4–6kWh/day in sun)
  

Scalability and Flexibility:

• Can hot-swap B300K modules if used in camping or remote off-grid setups
  

• Can expand to 4 modules per Apex without needing parallel setup
  

• If you begin adding HVAC or large appliances, consider parallel inverter setup (next section)
  

Whole-Home or High-Power Backup — For HVAC, Pumps, or EV Charging

Users who want to power an entire home with full automation, including high-load appliances like central air, water heaters,induction cooktops, and EV chargers. This setup is ideal for households aiming for energy independence and seamless off-grid capability — with smart power scheduling and real-time source switching.

Best for you if:

• You want to back up your entire home, not just a few essential devices
  

• You use central air conditioning, electric water heating, or induction cooking
  

• You need to charge an electric vehicle at full power (up to 11kW)
  

• You already have a rooftop solar system with microinverters, and want to add battery storage
  

• You want the system to automatically switch between grid and battery — no manual control
  

• You plan to set energy-use rules (eg use grid when battery is low,use battery when full)
  

• You want the system to recharge automatically via solar or generator
  

• You may occasionally detach one Apex 300 for portable use without shutting down the home

Recommended Setup

• 2× Apex 300 (parallel via Hub A1)
  

• 4–6× B300K
  

• Optional Add-ons:
  

• Hub A1 for parallel operation
  

• AT1 + Reliance Sub Panel for automatic whole-home switching
  

• SolarX 4K + rooftop solar for high-efficiency charging
  

• EV charger output cable (NEMA 14-50 or Tesla wall connector)
  

Total Usable Energy:

• 4× B300K = ~11.2kWh
  

• 6× B300K = ~16.8kWh
  Output Power Available:
  

• Up to 7,680W continuous with 2× Apex 300
  

• Up to 11,520W continuous with 3× Apex 300
  

Load Table: Whole-Home or High-Power Use Case

Runtime Estimate:

• 4 B300K = ~11.2kWh usable → covers a partial day of high-power use
  

• 6 B300K = ~16.8kWh → can cover a full day of selective whole-home use
  

• Solar or generator is strongly recommended for daily recharge cycles
  

UPS Support:

• Use AT1 + Sub Panel for full-home automatic switching
  

• Appliances should be divided into critical and non-critical circuits
  

• 0ms UPS support available for sensitive loads like servers or CPAPs
  

Charge Strategy:

• Turbo Mode via 50A grid input or generator
  

• SolarX 4K accepts rooftop PV input (up to 30kW array support,auto-down converted)
  

• Supports EV charger power draw if parallel output reaches 240V / 50A
  

Scalability and Flexibility:

• 3× Apex 300 = 11.5kW continuous output
  

• 6× B300K = over 16kWh capacity
  

• Supports microinverter PV systems, hybrid solar + grid input, and Smart Generator integration
  

• Plug-and-play hot swap possible for maintenance or portability (one Apex out, system keeps running)

Quick Comparison Table — Find Your Fit

This table summarizes the four main backup configurations with their use case, required modules, usable energy, and example loads supported.

Additional Notes:

• Energy use varies based on real usage patterns — actual runtime depends on appliance cycles, settings, and user behavior.
  

• Adding solar panels or a generator extends runtime significantly and reduces reliance on grid or battery storage alone.
  

• If you start with Light or Medium, your system is fully expandable — just add B300K batteries or parallel Apex units when needed.
  

• For full home backup with automatic switching, consider adding AT1 + Sub Panel and SolarX 4K for rooftop solar integration.