Home Battery or Large Power Station for Outages? Powerwall 3 and IQ 5P Against F3800 Plus and DELTA Pro 3
Summary
An installed home battery keeps the whole house, or the circuits you choose, running automatically and can take the rooftop array's full output; a large portable unit keeps the loads you plug in, costs a fraction installed, and needs no permit. In numbers: Powerwall 3 stores 13.5 kWh and delivers up to 11.5 kW; one IQ Battery 5P stores 5.0 kWh and delivers 3.84 kVA; Anker's F3800 Plus stores 3.84 kWh and delivers 6 kW, expandable to 53.8 kWh; EcoFlow's DELTA Pro 3 stores 4 kWh and delivers 4 kW, expandable to 48 kWh, and listed at $2,799 on October 4, 2026. EnergySage's installed price for a 13.5 kWh battery in our earlier guide was about $15,650.
The four, on the lines that matter for an outage
| Tesla Powerwall 3 | Enphase IQ Battery 5P | Anker SOLIX F3800 Plus | EcoFlow DELTA Pro 3 | |
|---|---|---|---|---|
| Energy per unit | 13.5 kWh | 5.0 kWh usable | 3,840 Wh | 4 kWh |
| Continuous power | 5.8 to 11.5 kW by installed rating; 15.4 kW off-grid option | 3.84 kVA | 6,000 W, 120 V and 240 V | 4,000 W, 120 V and 240 V; X-Boost to 6,000 W |
| Motor start | 185 LRA | 48 A LRA | not stated | not stated |
| Expansion | expansion units; charge up to 8 kW with three | more units, one per 20 A circuit | up to six BP3800, 53.8 kWh | extra batteries to 48 kWh |
| Solar input | 20 kW DC, six MPPTs | none; PV enters through microinverters | 3,200 W over two 165 V inputs | per-port figures not on the page we read |
| Switchover | automatic, with Backup Gateway | automatic, with IQ System Controller 3/3G | manual unless paired with a transfer panel | 20 ms with Smart Home Panel 2 ($1,599, electrician required) |
| Installation | licensed installer, permit | certified installer, permit | none for cord use | none for cord use |
| Price | about $15,650 installed for 13.5 kWh (EnergySage, in our earlier guide) | not listed; through distributors | not re-checked | $2,799 unit; $4,459 with one extra battery |
Where the home battery wins
Hardwired loads, 240 V circuits without a transfer panel, the furnace and well pump, and anything that must stay on while nobody is home. It also charges from the full array: Powerwall 3 takes 20 kW of DC, where the largest portable here takes 3.2 kW. And it is the only option that runs the whole house through a multi-day outage with solar refilling it, which our islanding guide describes.
Where the portable unit wins
Price, time and portability. A DELTA Pro 3 or F3800 Plus is bought, charged and in use the same week, with no permit; it moves to the campsite or the next house; and with a transfer panel added later it can grow into a partial-home system. For the loads in our 24-hour outage guide, a fridge, phones, lights and a router, 4 kWh covers the day without touching the house wiring.
The honest middle
A portable unit with a sub-panel sits between the two: automatic switchover and chosen circuits, at the cost of an electrician and a permit, tied to one brand's large units. Our guide on connecting a power station to the house walks through that route.
Shopping for one? Browse home backup power stations →
Sources
- Tesla — Powerwall 3 Datasheet
- Enphase — IQ Battery 5P Data Sheet
- Anker SOLIX — F3800 Plus Portable Power Station
- EcoFlow US — DELTA Pro 3 Portable Power Station
- EcoFlow US — Smart Home Panel 2
- EnergySage — How much do solar batteries cost? (as read for our installed-cost guide)
We have not tested these products. Specs, prices, stock and terms are as published on these pages on the date above and can change; check the manufacturer or retailer before you buy.