Start with what must stay on
Tell us whether your priority is the refrigerator and lights, a home office, selected circuits or larger equipment. Include any air conditioning, pumps or other loads you want reviewed. A designer must consider both the power those loads need at once and the energy they use over time.
We ask about your battery preference in the quote request. If you do not know your outage duration or target loads yet, leave them unknown rather than guessing. The proposal should identify unresolved requirements.
What a Powerwall 3 proposal should identify
We lead with Tesla Powerwall 3 for storage and backup options. Your proposal confirms the battery count, supported loads, required Gateway or Backup Switch, electrical work and compatibility with the proposed system.
- Which circuits or equipment are included in the backup scope?
- What reserve and operating assumptions support the estimate?
- Which site conditions could change the final design?
- What installation and warranty responsibilities are included in writing?
Battery runtime varies with loads, stored charge and conditions. Whole-home backup and uninterrupted operation are not guaranteed.
Three backup questions that a capacity number cannot answer
- Can it support the loads at the same time?
- A list of average energy use does not establish simultaneous power demand or motor startup requirements. Those need appropriate equipment and design information.
- Are those circuits actually backed up?
- The electrical design must identify the circuits, connection equipment and operating configuration. A battery on a proposal does not mean every circuit is supported.
- What assumptions describe the outage?
- Starting charge, reserve, actual usage and recharge conditions affect the result. A worksheet using assumed average loads does not establish a real outage duration.
See Tesla’s backup guidance and work through our illustrative energy budget. Then ask for project-specific confirmation.
Backup and bill management are different goals
Stored energy may be used for later consumption or reserved for outages, depending on configuration and operation. Comparing those priorities helps define what to request in the design. A battery should not be presented as a guaranteed bill reduction simply because one is included.
For a California proposal, ask for the utility-rate and export assumptions alongside battery behavior. See how utility context affects a solar review.
Compare with and without storage
Request the available solar-only and solar-plus-storage scopes when you need to see the cost difference. Keep the system design, cash price, financing terms and electrical work visible in the comparison. We will identify what needs confirmation before you proceed.
Sources and further reading
Source links checked October 30, 2026. Utility terms and offers can change; confirm the terms applicable to your project.