# EcoFlow Smart Home Panel 2, EV charger and generator inlet in a Seattle garage

> In December 2025 a Seattle homeowner wanted battery backup, a generator option and an EV charger on one garage wall. The work was a new 100 A subpanel, an EcoFlow Smart Home Panel 2 with a Delta Pro Ultra battery, a 50 A generator inlet with a panel interlock, and a 60 A circuit for an Emporia Pro charger. Seattle SDCI permit 7121395-EL.

*Source: https://hbpowerelectric.com/projects/seattle-smart-panel-ev-charger-generator-inlet/ · HB Power Electric, WA Electrical Contractor Lic. # HBPOWPE758PO · last updated 5 September 2026*

| Fact | Value |
|---|---|
| City | Seattle, King County |
| When | December 2025 |
| Property | Single-family home, attached garage |
| Scope | New 100 A subpanel, EcoFlow Smart Home Panel 2 with a Delta Pro Ultra battery, 50 A generator inlet with a panel interlock, and a 60 A hardwired circuit for an Emporia Pro EV charger. |
| Permitting authority | Seattle SDCI |
| Equipment | EcoFlow Smart Home Panel 2; EcoFlow Delta Pro Ultra; Emporia Pro EV charger; 100 A subpanel; 50 A generator inlet with interlock |

## What the homeowner needed

Three things on one garage wall. Backup that carries the furnace, the refrigerator, the network
gear and a few lighting circuits through a winter outage. A portable generator as the fallback for
night two. And a hardwired charger fast enough to fill a car overnight. The existing main load
center was full, so none of it had anywhere to land.

## Why the subpanel came first

A Smart Home Panel 2 does not create space, it consumes it. Where the room would come from was the
first thing this job had to settle. On site that meant opening the drywall around the existing load
center, cutting in the new enclosure beside it, and patching and priming the wall only after every
circuit had been landed and covered.

## What the Smart Home Panel 2 actually does

It is a transfer and control device, not a battery. Twelve branch circuits land on relay modules
inside it, each one switchable on its own. Separate GRID and GEN inputs feed it, and the Delta Pro
Ultra inverter and battery stacks connect to the power-station ports below. When the utility drops,
the panel moves those twelve circuits off the grid and onto the battery by itself, with nobody
home. Because every circuit has its own relay, low-priority loads can be shed to stretch the
remaining kilowatt-hours.

## Details that mattered here

Interlock kits are listed by panel brand and catalog number, so the kit has to be matched to the
existing load center before the inlet is ordered. Some panels have no listed kit at all, and then a
six-circuit manual transfer switch is the alternative.

Seattle is SDCI territory, not L&I, and under WAC 296-46B-901 the contractor buys the permit before
work starts. We have not photographed the exterior inlet box on this job, so the gallery here shows
the panels and the charger only.

## Frequently asked questions

### Why did this job need a subpanel before the smart panel?

Because the existing main load center was full. Twelve branch circuits had to come out of it and land inside the Smart Home Panel 2, the smart panel needed a feed, and the main panel still had to give up two double-pole slots for the generator backfeed breaker and the 60 A charger. A new 100 A subpanel created all of that room at once, which is why it is the first line on the SDCI permit.

### Can a battery and a generator work on the same panel?

Yes, and that is the point of this layout. The Smart Home Panel 2 has separate GRID and GEN inputs, so a portable generator plugged into the 50 A inlet can recharge the Delta Pro Ultra instead of the house running straight off the generator. The interlock on the main panel is the safety piece: it makes it mechanically impossible to close the main breaker and the generator breaker at the same time.

### Why is the EV charger not on the backed-up side?

A hardwired 48 A charger draws 11.5 kW at 240 V, which is more than the twelve backed-up circuits use together. Putting it behind the battery would drain the stacks during an outage for one load that can simply wait. The charger runs from the grid, or from the generator when one is connected, and the battery stays for heat, food, lights and network gear.

### Is the permit for this job actually public?

Yes. Seattle SDCI electrical permit 7121395-EL is a public record and can be looked up through the Seattle Services Portal by permit number. We publish the number and the scope, never the address. Seattle issues and inspects its own electrical permits, so L&I is not the authority inside city limits.


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HB POWER ELECTRIC LLC · 16125 Juanita Woodinville Way NE, Unit 302, Bothell, WA 98011 · (425) 239-4425 · info@hbpowerelectric.com
Washington Electrical Contractor Licence HBPOWPE758PO (General (01)), valid to 20 October 2027. UBI 605 986 025. $4,000 bond under RCW 19.28.041. Verify: https://secure.lni.wa.gov/verify/Detail.aspx?UBI=605986025&LIC=HBPOWPE758PO&SAW=