Whole-house comparison
How to compare whole-house backup systems
A whole-house label does not tell you which circuits stay on, how long they run, or whether large motor loads will start. Compare the designed system and the installed result—not battery capacity alone.
There are three different buying paths
| Path | What it powers | Connection | Right next step |
|---|---|---|---|
| Portable power station | Selected plug-in essentials | Temporary cords and portable solar within product limits | Measure loads and run the portable calculator |
| Panel-connected modular backup | Selected circuits, depending on the approved system | Supported smart panel or transfer equipment | Compare the exact ecosystem, then obtain qualified electrical review |
| Installed home battery | Designed essential circuits or broader home coverage | Permanent automatic-transfer and energy-management equipment | Obtain site-specific designs and itemized quotes |
Portable products can still be substantial and panel-connected systems can support many circuits. The boundary is the connection method and design responsibility—not a marketing use of the phrase “whole home.”
Compare the system, not the logo
| Representative system | Architecture | Question that changes the decision |
|---|---|---|
| Tesla Powerwall 3 | Integrated battery and solar inverter | Backed loads, motor-start demand, expansion, certified-installer design |
| FranklinWH aPower 2 | AC-coupled installed battery | Retrofit fit, 15 kWh increments, output, whole-home controller |
| Generac PWRcell 2 | Modular installed battery ecosystem | Exact model, cabinet capacity, transfer equipment, generator integration |
| Enphase IQ Battery 5P | Modular AC-coupled ecosystem | Unit count, system controller, outage configuration, commissioning |
| SolarEdge Home Battery | Inverter-linked battery ecosystem | Existing SolarEdge equipment, battery count, backup design, settings |
| Panasonic EVERVOLT | Installed battery configurations | Exact current configuration, inverter, supported loads, installer quote |
| Anker SOLIX X1 | Modular installed battery | Current U.S. specifications, system count, panel integration, installer support |
| EcoFlow OCEAN | Installed home-energy ecosystem | Current configuration, independent evidence, commissioning, support terms |
This is a coverage map, not a ranking or recommendation. Product versions, regional availability, warranties, and supported configurations change. The current manufacturer documentation and the exact installer proposal control.
Eight fields every quote must answer
- 1Backed loads
Name every supported circuit, every excluded load, and any automatic load-shedding rule. Call out HVAC, well pumps, water heating, cooking, EV charging, and other large 240-volt loads.
- 2Usable energy
Record usable kWh at the proposed configuration and reserve setting, separate from nameplate capacity.
- 3Continuous and startup power
Compare continuous output with the coincident load and verify motor-start behavior for the actual equipment.
- 4Outage operation
Document automatic transfer, grid-forming or island behavior, black-start limits, manual steps, and what happens at the reserve threshold.
- 5Solar during an outage
State whether solar can operate while the grid is down, the recharge limit, required hardware, and the assumptions behind any multi-day claim.
- 6Electrical scope
Include panels, service upgrades, gateways, transfer equipment, load controls, permits, utility work, and monitoring.
- 7Total installed price
Compare equipment, labor, required electrical work, permits, monitoring, service, and maintenance—not a battery-only price.
- 8Warranty and support
Separate equipment, labor, performance, and capacity-retention coverage. Identify who services the system after installation.
Require a real outage commissioning test
- Simulate a grid outage and confirm the intended circuits remain powered.
- Start the largest supported motor load while other essential loads are operating.
- Confirm reserve settings, load controls, monitoring, notifications, and manual recovery steps.
- If solar is included, document what the system does when solar is available during an outage.
- Record the final configuration and emergency support contacts before signoff.
A commissioning result is evidence about the installed home. It is more useful than transferring another owner's runtime story to a different house.
Start in the correct lane
If the plan is limited to movable plug-in essentials, use the calculator and rehearse the setup. If it reaches fixed circuits, automatic transfer, rooftop solar, or large 240-volt loads, move to a qualified site-specific design.
Choose the backup pathway →No whole-home manufacturer, installer, marketplace, or referral relationship is active. This guide is quote preparation, not electrical design or an installer recommendation.
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