Safety warnings
Use your generator as directed. Every generator is different—follow the instructions in your generator’s manual for safe operation and maintenance.
Never run your generator indoors. Always place it outside, at least 20 feet from your home, windows, vents, and your Base battery. Generators produce carbon monoxide, which cannot be seen or smelled and is life-threatening even in small amounts.
Use the right cord. A NEMA L14-30 extension cord (25+ feet, outdoor-rated) is required. Other cords or adapters could be unsafe.
Keep cords in good shape. Don’t use extension cords with exposed or damaged wiring.
Check the port before you plug in. Make sure the Generator Recharge Port and cable are free of rust or debris before use. If anything looks off, don’t plug in—reach out to our team.
Secure the inlet lid. After use, close the lid on the Generator inlet to keep out rain.
How does this extend my backup duration?
When active, the Generator Recharge Port contributes a steady 3kW to power the home in a grid outage. If the home is consuming less than 3kW, the extra power recharges the battery. If the home is consuming more than 3kW, the battery and Generator Recharge Port work together to power the home, draining the battery less quickly. Read more about backup duration here.
The table below outlines some example scenarios for a Single Ground-Mounted Battery (25kWh) with a generator connected.
Charge entering outage / power usage | Low power usage (750W) | Medium power usage (1.5kW) | High power usage (4.5kW) |
Minimum battery charge (20%) | 🔋Battery will fully charge in ~9 hours. | 🔋Battery will fully charge in ~13 hours. | 🪫Battery will fully drain in ~3 hours. |
Medium battery charge (60%) | 🔋Battery will fully charge in ~5 hours. | 🔋Battery will fully charge in ~7 hours. | 🪫Battery will fully drain in ~10 hours. |
Full battery charge (100%) | 🔋Battery will stay fully charged. | 🔋Battery will stay fully charged. | 🪫Battery will fully drain in ~17 hours. |
The table below outlines some example scenarios for a Double Ground-Mounted Battery (50kWh).
Charge entering outage / power usage | Low power usage (750W) | Medium power usage (1.5kW) | High power usage (4.5kW) |
Minimum battery charge (20%) | 🔋Battery will fully charge in ~18 hours. | 🔋Battery will fully charge in ~27 hours. | 🪫Battery will fully drain in ~7 hours. |
Medium battery charge (60%) | 🔋Battery will fully charge in ~9 hours. | 🔋Battery will fully charge in ~13 hours. | 🪫Battery will fully drain in ~20 hours. |
Full battery charge (100%) | 🔋Battery will stay fully charged. | 🔋Battery will stay fully charged. | 🪫Battery will fully drain in ~33 hours. |
How is this different from a generator interlock?
| Generator Interlock | Generator Recharge Port |
Activation | You have to manually switch a breaker and power on your generator to restore power in an outage. | Battery backup is automatic, and you can plug in your generator if you choose. |
Generator Capacity | Your generator must be large enough to support your home’s peak power usage. | Your generator can be smaller as the battery will support high power usage up to 11.4kW. |
Disconnection | Unplugging or powering off your generator cuts off your home power. | You can disconnect your generator without interrupting your home’s power. This gives you flexibility for refueling, maintenance, and quiet hours. |
Home Voltage | Your home’s voltage depends on the quality of your generator. The instability may harm sensitive electronics. | Your home’s voltage remains stable as it is coming from the Base inverter, not a generator. |
What do I need to use the Generator Recharge Port?
You can use nearly any 240V portable gas generator with the Generator Recharge Port as long as it meets the following specifications. We also recommend a few options below.
System specifications
Required Generator Output Voltage | 240V |
Required Generator Receptacle Type | NEMA L14-30R |
Required Generator Running Wattage | Minimum 4kW (4000W) |
Base Maximum Recharge Power | Up to 3kW (3000W) |
Portable generator output voltage rating
The Generator Recharge Port is only compatible with 240V power sources. Do not attempt to use a 120V port on a generator with an adapter cable as it will not work.
Portable generator power rating
While the Generator Recharge Port sends up to 3kW into your battery and/or home, your generator must have a Running Wattage of at least 4kW.
Note that some manufacturers advertise “Peak” or “Surge” Wattage instead, so be sure to check that the true Running Wattage exceeds 4kW. If your generator is not capable of continuous 4kW, it will stall.
For higher fuel efficiency, Base recommends generators with at least 6kW Running Wattage.
Recommended portable generators
We’ve tested and recommend the following generators based on ease of use, compatibility, and reliability.
Option 1: [Home Depot] Generac GP6500 Gasoline Powered Portable Generator
Easy to use with features such as push-to-start and auto-choke
Has CO detection and automatic shut-off
Manual pull-start in case lead-acid battery dies
Big 8 gallon tank
Oil change needed every 100 hours
Assembly: Wheels and handle take ~30 minutes with basic tools (2 pliers, wrenches optional)
Option 2: [Costco] Generac GP9200E Gasoline Powered Portable Generator
Easy to use with features such as push-to-start and auto-choke
Has CO detection and automatic shut-off
Manual pull-start in case lead-acid battery dies
Big 8 gallon tank
Oil change needed every 100 hours
Assembly: Wheels and handle take ~30 minutes with basic tools (2 pliers, wrenches optional)
Option 3: [Amazon] WEN DF680iX Quiet Portable Generator
Quieter, smaller, and easy to roll around
Easy to use with features such as push-to-start and auto-choke
Has CO detection and automatic shut-off
Manual pull-start in case lead-acid battery dies
Smaller 3 gallon tank may need multiple refills per day
Oil change needed every 100 hours
Very little assembly
What cable do I need?
You need to have a NEMA L14-30 extension cord that is at least 25 feet long, which you can get from Amazon or Home Depot. This cord will plug into the Generator Recharge Port on one end and a generator’s NEMA L14-30R receptacle on the other end. Adapters may not be supported; use adapters at your own risk.
NEMA L14-30 extension cord
NEMA L14-30R receptacle on a generator
NEMA L14-30P port on the Base battery
How to connect your generator during an outage
Note that the Base battery system will only accept generator power when the grid is in an outage.
To avoid carbon monoxide exposure, position the generator outside at least 20 feet away from the battery, people, doors, open windows, and vents. Never use a generator indoors or in garages.
Before plugging anything in, start your generator by following the instructions provided in the generator’s manual.
Plug in your NEMA L14-30 generator cable to the Generator Recharge Port first.
Plug in the other end of the cable to the generator second.
The Generator Recharge Port should automatically start sending power from the generator to your Base battery. You may hear your generator respond to the increase in power after a few seconds. Currently, the Base mobile app does not display power from the generator.
If you want to refuel or service the generator, follow the instructions in the next section to disconnect your generator first. Your home backup will not be interrupted as long as your battery does not fully drain.
If the grid comes back, the Generator Recharge Port will automatically stop drawing power from the generator. However, your generator will still be running until you turn it off. Follow the instructions in the next section to disconnect your generator.
Generator Recharge Port in use during an outage.
How to disconnect your generator
Turn off the generator by following the instructions in your generator’s manual.
Unplug the cable from your Base battery, then from your generator.
Wait at least 30 minutes before bringing the generator indoors, as it may continue to emit carbon monoxide fumes even while turned off. See your generator’s manual for specific guidance.
Test your system periodically
Base recommends proactively testing your generator and Generator Recharge Port at least every 3 months to ensure the full system is functional in the event of an extended power grid outage. In order to test the Generator Recharge Port:
Simulate a grid outage by switching the main breaker in your Base system (pictured below) to the OFF position. Access the breaker by unscrewing the black knobs on the dark tinted door.
Follow the above instructions to connect and use your generator as you would during a grid outage.
Verify that the battery is receiving 3kW of generator power in the app.
Power down your generator system following the above instructions.
Reconnect your home to the grid by switching the main breaker (pictured below) to the ON position.
Close the dark tinted door and tighten the black knobs to seal it.
Location of the 200A breaker.
Can I plug in something that’s not a generator?
While some standalone battery products can output 240V power and may work with our system, we don’t recommend using them with the Generator Recharge Port since they will drain fairly quickly. For example, an external 3kWh battery would drain in just one hour. Even if the external battery comes with a solar panel, the power output will likely not be sufficient to keep up.
However, some vehicles have 240V ports that are capable of powering the Generator Recharge Port.
Tesla Cybertruck (see Tesla website for instructions)
Ford F-150 or F-150 Lightning with Pro Power Onboard™ 7.2kW or 9.6kW (see Ford website to check if your vehicle has a 240V cargo bed outlet)
Liability Disclaimers
Base Power does not manufacture, sell, or warrant any generators. We provide only the integration equipment that enables a third-party generator to be used alongside a Base Power battery.
Customers are responsible for selecting, installing, operating, and maintaining any generator used with our system.
Base Power is not liable for any damages, malfunctions, or safety hazards resulting from
Improper use of a generator,
Faulty or non-compliance generator equipment,
Use of the generator during adverse conditions (e.g., indoor use)
Base Power’s warranty does not cover damage caused by generator-related faults.