Research
Refrigerator outage sizing table
Fifteen transparent scenarios converting an EnergyGuide annual kWh figure into 24-, 48- and 72-hour outage capacity screens. Every assumption is visible, and every gate that capacity cannot answer stays open.
Last updated 10 August 2026
Published 10 August 2026 · Last reviewed 10 August 2026 · Model version 1.0
By Alexis Marchais, engineer and independent decision-system builder. Reviewed quarterly, or immediately after any formula, source or rule change.
The one-sentence answer
An annual kWh figure can estimate a capacity screen, but it cannot certify continuous output, compressor startup, recharge, safety, food safety, or product fit.
The formula
Reproduce every row below with one expression:
Required nominal Wh = (annual kWh × 1,000 ÷ 365 × outage days − declared recharge credit) ÷ (AC delivery factor × retained reserve factor)
Outage days = outage hours ÷ 24. Daily outlet Wh = annual kWh × 1,000 ÷ 365. The two factors multiply to the combined planning factor of 0.765.
Assumptions, stated in the open
AC delivery factor 0.85
An editorial planning factor for inverter and conversion losses. It is not a product measurement and no unit was tested to produce it.
Retained reserve factor 0.90
Ten percent of stored energy is left unallocated and never planned against. Also an editorial choice, applied against the reader.
Combined planning factor 0.765
0.85 × 0.90 = 0.765. This single factor converts outlet energy demand into required nominal capacity in every row of the table.
Recharge credit 0 Wh/day
The published baseline credits no recharge at all. A recharge input is only credited once it is evidenced, which is why the 48- and 72-hour rows leave the recharge gate open.
The 15 scenarios
Annual use 300 / 400 / 500 / 600 / 700 kWh per year, crossed with 24, 48 and 72 hours. Displayed values are rounded to one decimal; the downloads below remain canonical.
| Case | Annual kWh | Duration | Daily outlet Wh | Outage outlet Wh | Recharge credit | Required nominal Wh | 1 kWh screen | 2 kWh screen | Startup surge | Decision status |
|---|---|---|---|---|---|---|---|---|---|---|
| R-01 | 300 | 24 h | 821.9 | 821.9 | 0 Wh | 1,074.4 | Fail — capacity | Pass — capacity only | Verify or measure | Capacity screen only |
| R-02 | 300 | 48 h | 821.9 | 1,643.8 | 0 Wh | 2,148.8 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-03 | 300 | 72 h | 821.9 | 2,465.8 | 0 Wh | 3,223.2 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-04 | 400 | 24 h | 1,095.9 | 1,095.9 | 0 Wh | 1,432.5 | Fail — capacity | Pass — capacity only | Verify or measure | Capacity screen only |
| R-05 | 400 | 48 h | 1,095.9 | 2,191.8 | 0 Wh | 2,865.1 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-06 | 400 | 72 h | 1,095.9 | 3,287.7 | 0 Wh | 4,297.6 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-07 | 500 | 24 h | 1,369.9 | 1,369.9 | 0 Wh | 1,790.7 | Fail — capacity | Pass — capacity only | Verify or measure | Capacity screen only |
| R-08 | 500 | 48 h | 1,369.9 | 2,739.7 | 0 Wh | 3,581.3 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-09 | 500 | 72 h | 1,369.9 | 4,109.6 | 0 Wh | 5,372 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-10 | 600 | 24 h | 1,643.8 | 1,643.8 | 0 Wh | 2,148.8 | Fail — capacity | Fail — capacity | Verify or measure | Capacity screen only |
| R-11 | 600 | 48 h | 1,643.8 | 3,287.7 | 0 Wh | 4,297.6 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-12 | 600 | 72 h | 1,643.8 | 4,931.5 | 0 Wh | 6,446.4 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-13 | 700 | 24 h | 1,917.8 | 1,917.8 | 0 Wh | 2,506.9 | Fail — capacity | Fail — capacity | Verify or measure | Capacity screen only |
| R-14 | 700 | 48 h | 1,917.8 | 3,835.6 | 0 Wh | 5,013.9 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
| R-15 | 700 | 72 h | 1,917.8 | 5,753.4 | 0 Wh | 7,520.8 | Fail — capacity | Fail — capacity | Verify or measure | Recharge gate open / architecture review |
Both files carry the same 15 cases, the model version and the review date, so any figure quoted from this page can be recomputed independently.
Four gates, never collapsed into one
A capacity screen answers exactly one of these four questions. The other three stay visibly open until evidence closes them.
- Capacity
- Screened in the table above. This is the only gate an annual kWh figure can address, and passing it means capacity only.
- Continuous output
- Not evaluated — requires declared simultaneous load. It is never reported as PASS from energy alone.
- Startup surge
- Verify or measure. Compressor startup demand cannot be derived from watt-hours; it must be measured or evidenced.
- Recharge closure
- For any duration above 24 hours with zero credible recharge, the status is “Recharge gate open / architecture review”, not a larger battery.
Abstention and measurement rules
- AR-01MEASURE
Startup watts unknown
Measure compressor startup or obtain comparable test evidence. Capacity cannot establish compatibility.
- AR-02NO FIT
Continuous output below declared simultaneous load
Change product class or reduce declared simultaneity. The load cannot be sustained.
- AR-03ARCHITECTURE REVIEW
Outage above 24 h and no credible recharge path
Test installed backup or a generator-hybrid architecture. Storage alone may only delay failure.
- AR-04VERIFY
Recharge credit estimated but not measured
Use a conservative zero until evidence exists. A speculative input cannot close the loop.
- AR-05HOLD
Product evidence stale, territorial or incomplete
Refresh exact SKU evidence and availability date. A product cannot be exposed on incomplete evidence.
Worked example: 500 kWh per year, 24 hours
- Declared annual energy
- 500 kWh/year
- Daily outlet demand — 500,000 ÷ 365
- 1,369.9 Wh
- Outage outlet demand — 1 day
- 1,369.9 Wh
- Declared recharge credit
- 0 Wh
- Required nominal capacity — ÷ 0.765
- 1,790.7 Wh
That figure is a capacity screen and nothing more. It does not certify that any station will start the compressor, that its continuous output covers whatever else is plugged in, or that a specific refrigerator or station is a fit. Those remain open gates.
Primary sources
- How to use the EnergyGuide label when shopping for home appliancesUS Federal Trade Commission
Reviewed 10 August 2026 · Boundary: Reports yearly energy use. It does not establish outage runtime or compressor startup surge.
- Refrigerator and freezer energy rating online search toolUS Department of Energy
Reviewed 10 August 2026 · Boundary: A model input, not a field measurement of your own unit.
- ENERGY STAR certified residential refrigeratorsUS Environmental Protection Agency
Reviewed 10 August 2026 · Boundary: A certified dataset with annual energy use, limited to listed models.
- Before the Battery methodologyBefore the Battery
Reviewed 10 August 2026 · Boundary: The 0.85 AC delivery factor and the 0.90 retained reserve factor are editorial planning assumptions, not independent tests.
- Before the Battery revision logBefore the Battery
Reviewed 10 August 2026 · Boundary: Dated record of publication, corrections and rule changes for this table.
Version history and corrections
- v1.0 — 10 August 2026
- First publication. Fifteen cases, 0.85 AC delivery factor, 0.90 retained reserve factor, zero recharge credit in the baseline, four separate gates and five abstention rules.
Reviewed quarterly, or immediately after any formula, source or rule change. Every change is dated in the revision log. Found an error? Write to editor@beforethebattery.com or use the contact page; corrections are published with their date.
Run your own numbers
The table is a screen for typical annual figures. The refrigerator check applies the same arithmetic to your declared outage length, running watts, startup watts and recharge, and tells you which gates stay open.
Run the refrigerator check