The short answer
Essential-circuit backup supplies an agreed selection of loads. Whole-home backup covers a broader installation, but its equipment limits and operating rules still need to be defined.
Make two lists
First, list the loads you need during an outage. Then list the loads you would be happy to postpone. Put communications, lighting and any critical equipment into the discussion with the designer.
For equipment on which health or safety depends, obtain a specific resilience design rather than relying on a general household battery estimate.
Compare simultaneous demand
If the essential loads are drawing 0.3 kW at a particular moment, switching on a 3 kW appliance raises demand to about 3.3 kW, before any starting surge. The appliance also consumes additional energy while running.
This distinction helps explain why a list of connected circuits does not establish unlimited use. Starting loads and the complete system’s operating limits need checking.
Get the system boundaries in writing
Ask which circuits and phases are supplied, how separation from the grid is achieved, and what happens when available energy is low. Confirm whether existing solar can operate within the proposed backup arrangement.
Request a commissioning demonstration and accessible handover instructions. Manufacturer examples illustrate possibilities, but do not establish compatibility for another product.
Record the preference in SolarIQ
You can request a Whole Home Backup assessment alongside a solar-and-battery estimate. That records an interest for the installer; it does not mean backup hardware or electrical alterations are included.
Compare the surveyed backup proposal separately, with its own equipment list, coverage and operating conditions.
Before your assessment
Bring these questions with you.
- Essential and deferrable loads.
- Supported circuits and phases.
- Continuous power, starting loads and reserve.
- Commissioning and handover arrangements.