A line-by-line proposal checklist for home battery quotes: usable kWh, continuous and surge power, protected loads, permits, commissioning, and a scoring rule.
Final Decision
Quick answer: A complete home battery proposal states battery count and usable kWh, continuous power, surge (peak) power with duration if the manufacturer publishes one, gateway hardware, a protected-load list by circuit, panel or busbar interconnection work, permits and permission to operate, commissioning, incentive assumptions with an effective date, and financing costs. Score each item present, vague, or missing before you compare price. Checked September 23, 2026.
Best for
Homeowners comparing battery quotes in US.
Wrong fit
Off-grid cabins, RV systems, marine systems, or commercial storage projects.
Tradeoff
A lower quote is not better until the backup design, usable kWh, surge power, and incentive assumptions match.
Read a battery quote by checking what it states, line by line, before you compare totals. A fair proposal names the battery count, usable kWh, continuous and surge power, backup design, gateway hardware, protected loads, panel or interconnection work, permits, commissioning, incentive assumptions, and financing costs.
The goal is not to pick the biggest battery. The goal is to see whether the proposal in front of you is actually complete, so a low number is not just a missing line item in disguise.
Before comparing totals, check the costs commonly excluded from a first home battery quote: panel and utility service work, gateway hardware, trenching, permits and interconnection, commissioning, removal, and finish work. Require each category to be marked included, excluded, or not yet assessed.
If the installer offers a loan, lease, or PPA alongside the cash price, get the cash price in writing first. A financed monthly payment is not comparable to a cash total until you know what home battery financing actually costs on top of the hardware and labor.
The proposal checklist
This is the row-by-row version of the quick answer. A proposal does not need to solve every row in your favor, it needs to state an answer for every row.
Line item
What a complete proposal states
Why it matters
Battery count and usable kWh
Number of units and usable capacity, not just nominal capacity
Usable kWh is the number that actually backs up your house
Continuous power
The kW the system can sustain, per unit and combined
The short-burst power rating and, if the manufacturer publishes one, how long it lasts
Motors (AC compressors, well pumps) draw a brief surge well above running watts; a battery can trip on start-up even when its continuous rating looks fine on paper
Gateway or backup controller
Exact make, model, and quantity
The hardware that islands the home from the grid during an outage
Protected-load list
Which circuits are backed up, ideally by breaker number, not just "essentials" or "whole home" as a phrase
Whether your existing panel and busbar clear the interconnection math, or what has to change
Battery inverters share the busbar with your utility feed; older or fully loaded panels often cannot take a battery without upgrade work. Full math in the panel upgrade cost guide
Permits and permission to operate
Who files, who pays, and that the system cannot legally run until the utility signs off
Skipping this step, or not knowing it exists, is how a homeowner ends up running an uninspected system
Commissioning
Startup, app and gateway configuration, a test of backup transfer, and a documentation handoff
This is the step that proves the system actually does what the quote promised, not just that it is wired in
Incentive assumptions
Which programs, at what dollar amount, with an effective date
Incentive levels change; a number with no date is not verifiable
Financing costs
Loan dealer fees, lease or PPA escalators, or confirmation the price is cash
A financed monthly payment is not comparable to a cash total
Surge power: the number most quotes skip
Continuous power tells you what a battery can run steadily. Surge (peak) power tells you whether it can start a motor at all. Manufacturers publish this differently, and not every one states how long the surge lasts. These are the three most-quoted whole-home systems, checked directly against their own datasheets on September 23, 2026:
System
Continuous power
Surge/peak power
Duration
Tesla Powerwall 3
11.5 kW AC
185 A locked-rotor-amps (LRA) motor-start rating
Not published by Tesla
Enphase IQ Battery 5P (US)
3.84 kVA per unit
32 A peak output current (7.68 kVA), plus up to 48 A LRA "Power Start"
3 seconds at 32 A; 25.6 A (6.14 kVA) sustained to 10 seconds
FranklinWH aPower 2
10 kW / 11.5 kVA
15 kW peak; 25 kW transient; 185 A LRA load-start
15 kW for 10 seconds; 25 kW for 1 second
A quote that only states continuous power has not shown you the number that decides whether a central AC compressor, well pump, or sump pump actually starts. If your installer cannot answer what the surge rating is for the exact hardware on your proposal, ask them to pull it from the datasheet before you sign, not from memory.
Protected loads: ask for a circuit list, not a promise
"Whole-home backup" and "essential loads" are backup-design phrases, not proof of what actually happens during an outage. A complete proposal lists the circuits by breaker, with running and starting watts for anything with a motor. The whole-home vs essential-loads guide has the full circuit-by-circuit wattage table (refrigerator, furnace blower, sump pump, well pump, central AC, and more) to check your installer's list against.
If your proposal names a backup design but never lists the circuits behind it, that is a gap to close before signing, not a detail to assume later.
Permits, permission to operate, and commissioning
Two steps get skipped over in a lot of sales conversations, and both matter more than most line items on the invoice.
Permission to operate (PTO) is the utility's written sign-off, issued after a local inspector approves the completed work, that the system is cleared to run. Pacific Gas & Electric's own solar guidance states plainly: "For safety reasons, don't turn on your system until PG&E gives you official written permission to operate it." The exact process and typical timeline vary by utility, so confirm your own utility's steps and timeline rather than assuming PG&E's process applies everywhere; ask your installer who files for PTO and who is responsible if it is delayed.
Commissioning is the startup and verification work after the hardware is physically installed. The industry's own Energy Storage Installation Professional task list, published by NABCEP, describes commissioning as including a commissioning protocol, a visual inspection, communication and system tests, verifying that backup (islanding) transfer actually works, and a documentation handoff: a commission report, test results, signed permits, the permission-to-operate confirmation, and as-built drawings. A proposal that never mentions commissioning has not told you how, or whether, the installer proves the system works before leaving.
Score the proposal
This is our own review heuristic, not an industry standard. Score each of the ten rows in the checklist above: 2 points if the proposal states it with a specific number or named item, 1 point if it is mentioned but vague, 0 if it is missing entirely. Add it up out of 20.
16-20: The proposal is specific enough to compare on price and design.
10-15: Send the copy-paste email below before you sign anything.
Under 10: Treat this as a placeholder, not a real quote. Get a second proposal.
A high score does not mean the price is fair, only that you can tell what you are pricing. Run the number itself through the quote calculator or our free quote review.
Copy-paste email to send your installer
If your proposal is missing rows, send this instead of guessing:
Subject: A few items missing from the proposal
Hi [installer name],
Before I compare this to other quotes, could you confirm the following in writing:
Usable kWh and continuous power for the exact battery model quoted
The surge/peak power rating for that model, and how long it holds if published
Gateway or backup controller make, model, and quantity
The protected-load list by breaker, with which circuits are backed up
Whether my panel or busbar needs any work for the interconnection, and why
Who files for permits and permission to operate, and the typical timeline
What commissioning includes, and whether I get a written test/completion report
Which incentive programs and dollar amounts are assumed, and their effective date
Thanks, I just want the full scope before I decide.
[Your name]
Quote red flags
No usable kWh shown, or usable kWh not distinguished from nominal capacity.
Continuous power is stated but surge/peak power is never mentioned, even for a design that has to start a motor load.
No utility or state incentive assumptions shown, or a number with no effective date.
Gateway, trenching, panel, permit, or interconnection work is left as "as needed" with no allowance or cap.
Installer refuses to explain the backup-loads design or cannot name the protected circuits.
Permits, permission to operate, or commissioning are never mentioned in the proposal at all.
Commercial note
Home Battery Guide may earn from affiliate links or flat-fee referrals to named vetted installers. Rankings do not move with compensation. We do not sell the same lead to multiple installers, and a referred installer quote still has to pass the same quote check.
FAQ
Can I compare two quotes by total price only?
No. One may include panel work, whole-home backup, or a second battery. Compare scope first, then price.
What is surge power and why does my quote need it?
Surge (or peak) power is the short burst of output a battery can supply above its steady continuous rating, which is what actually starts a motor like a central AC compressor or well pump. A quote that only lists continuous power has not shown you whether your specific loads will start.
What is permission to operate?
It is the utility's written authorization, issued after a local inspector approves the work, that clears the system to run. The system should not be switched on before it arrives. Ask your installer who files for it and the expected timeline for your utility.
Should I send the installer my competing quote?
You can, but first understand the line items. Otherwise the conversation turns into discount theater instead of scope clarity.
What we could not verify this run
Tesla's own datasheet states a 185 A locked-rotor-amps motor-start rating for Powerwall 3 but publishes no duration for that figure. Third-party estimates of how long that surge lasts exist but are not a Tesla-stated number, so we left it out rather than repeat an unverified figure.
Permission-to-operate timelines and filing responsibility vary by utility. We verified Pacific Gas & Electric's own description as a representative example, not as a claim that every US utility follows the same process or timeline.
These guides are built from public specifications, primary program pages, utility documentation, manufacturer materials, and repeated buyer questions that show up in quote and installation decisions.
Manufacturer and installer responses can clarify pricing bands, warranty terms, support footprint, and common mistakes. They do not move a page up the shortlist on their own.
