Battery Backup With a Generator Plug: How the FOX ESS Hub G2 Gets a Tampa Bay Home Through a Hurricane
The question we hear most from Tampa Bay homeowners after a storm season is some version of: "Do I want a battery or a generator?" For eighteen years Fused Solar and Roofing answered that by installing standby generators. In 2026 our answer is a battery that knows how to run a generator, and the piece of equipment that makes that possible is the FOX ESS Fox Hub G2. This article explains what the Hub does, how an outage actually plays out with one on the wall, and how it compares with the Tesla and Enphase approaches.
What the Fox Hub G2 is
The Fox Hub G2 is a 200 A smart hub that sits between the utility meter, your main panel, the FOX ESS inverter and battery stack, and, if you have one, a generator. According to the FOX ESS datasheet (V2.0, May 2026), it detects a grid failure and disconnects in under 20 milliseconds, so the lights do not flicker; it carries the whole house on battery power; it has three smart circuits it can switch off by itself (one 240 V and two 120 V); it has a wired generator input with a two-wire auto-start; and it supports up to four FOX ESS inverters on one Hub. It is Type 3R rated for outdoor mounting, runs silently with no fan, and carries a 12.5-year warranty, the same as the FOX ESS inverter and batteries.
What we put with it
Our standard FOX ESS package in Tampa Bay is the PowerQ 11.4 kW all-in-one hybrid inverter with five EQ4000 lithium iron phosphate battery modules stacked under it, 19.85 kWh in total, expandable to 27.8 kWh on the same stack. The 11.4 kW of continuous backup power runs the whole home including central air conditioning. Panel-level monitoring and rapid shutdown come from Tigo units on every solar panel. Everything mounts outside on an exterior wall.
How an outage plays out
Hour zero. The grid drops. The Hub opens in under 20 ms. The house is on battery. If it is daytime, the solar array keeps producing and the battery keeps charging. Nobody inside notices unless they are watching the app.
The first evening. The air conditioning is running and the battery is doing the work. In the FoxCloud app you set the battery level at which the smart circuits shut off. The pool pump, the second AC or the dryer, whatever you put on those three circuits, drops out on its own when the bank reaches that level. The kitchen, the lights, the internet and the main AC stay on.
Day two or three, if the clouds stay. This is the part a battery alone cannot handle and where most battery owners start rationing. With a generator wired to the Hub's terminal, the Hub starts it on the two-wire contact when the battery is depleted, carries the house, and shuts the generator down as soon as solar is back on the panels. The generator runs for a fraction of the hours it would on its own, uses a fraction of the fuel, and you never walk outside to flip a transfer switch in the rain.
Grid returns. The Hub reconnects, the battery tops back up on solar, and the system goes back to cutting your bill every day. That is the other half of the case for a battery over a generator: the generator only earns its keep during an outage, while the battery works 365 days a year.
Why a battery first, generator second
We installed generators long enough to know their weak points in this climate. They sit at ground level, where storm surge and salt water reach them. They need fuel during the exact week fuel is hardest to get. They need oil changes and weekly exercise cycles. And they are loud, which matters when the whole street is running them. A battery mounts on the wall above surge level, is silent, has no fuel and no maintenance beyond an annual inspection, and starts in milliseconds. For most Tampa Bay homes the battery wins outright. The Hub's generator input is for the homeowner who already owns a generator, or the one who wants the belt and suspenders of a two-week outage plan.
How Tesla and Enphase handle the same job
Tesla Powerwall 3 backs up the house through a Backup Gateway 2 or Backup Switch. Generator integration is not listed on the Powerwall 3 datasheet, and shedding loads needs a separate smart panel or load controller. Enphase backs up through the IQ System Controller; generator support requires the 3G version of that controller, and load shedding likewise needs a separate device. Both are capable systems, and Fused installs and services both. The difference is that FOX ESS puts the transfer, the smart circuits and the generator terminal into one 200 A box, which means fewer devices, fewer permit line items and fewer things to coordinate on install day.
Sizing it right
At the site review we look at four things: the size of your electrical service and main panel, which loads you want backed up and which can be shed, whether a generator exists or is planned, and where the stack and Hub will mount outside. Five battery modules is our standard because it covers a typical Tampa Bay home with AC through a night; homes with two air handlers, a pool and an EV may want six or seven. The Hub's four-inverter capacity means the system can grow later without replacing anything.
Frequently asked questions
Q: Does the generator charge the battery?
A: The Hub's job is to carry the house on the generator when the battery is depleted and hand back to solar and battery as soon as it can. How the generator interacts with battery charging depends on configuration, and we set it up with you at commissioning. What matters day to day is that the generator starts and stops by itself.
Q: What size generator can I connect?
A: The Hub's generator input is rated well above anything a residential standby or portable generator produces. We size the connection to your generator at the site review and wire it to the Hub's dedicated generator conduit.
Q: Do I need a smart panel like SPAN?
A: Not for the three circuits the Hub manages. If you want per-circuit control of every breaker in the house, a SPAN panel is still available, and Fused is SPAN-certified. Most homes find the three Hub circuits cover the loads worth shedding.
Q: Can the Hub work with my existing solar?
A: The Hub pairs with FOX ESS inverters. If you have solar from another brand and want a battery, we can add FOX ESS AC-coupled, or FranklinWH, depending on your inverter. We tell you which at the site review.
Specifications in this article come from each manufacturer's published datasheets: FOX ESS PowerQ (V1.6, July 2026), EQ4000 (V2.3, October 2026) and Fox Hub G2 (V2.0, May 2026) from us.fox-ess.com; the Tesla Powerwall 3 2024 North America datasheet; and Enphase's IQ Battery 5P specifications. Check the current datasheet before relying on any figure; manufacturers revise them.
Fused Solar and Roofing is a licensed roofing (CCC1331058), electrical (EC13014750), and building contractor (CBC1252064), all three in-house, serving Hillsborough, Pinellas, Pasco, and Manatee counties since 2007. Fused Solar and Roofing is an EnergySage Elite Installer with a 5.0/5 rating and 21+ verified reviews, independent verification, earned not purchased.
Thinking about a battery, or a battery with a generator? See the FOX ESS system we install at https://fusedsolarandroofing.com/fox-ess-battery, or request a site review at https://fusedsolarandroofing.com/contact. Battery systems are priced after a site review; we do not publish battery prices because the panel, wiring and backup scope change the number.
