Independent portable-power decision support · US
Know what must stay on before you buy the battery.
Two free checks size your refrigerator outage or your RV weekend from the hours, loads and recharge you actually have — and say plainly when no portable station fits.
About 2 minutes · No email · No brand choice
Choose your situation
Two live checks. Pick the one that is yours.
- Refrigerator during an outageUC-03Will 1,000 Wh or 2,000 Wh keep your refrigerator cold?One number from your EnergyGuide label and your outage length. You get the hours, the compressor-start gate, and whether daily recharge closes.For a 72-hour outage, 2 kWh can fail without enough daily recharge.Check my refrigerator2 min · one label figureAt riskDead outletStationTemp. vs hours off
- RV or travel-trailer weekendUC-06Is a portable station enough for two nights without hookups?Start from shore power, TT-30, the battery you already own and the loads you will actually run after sunset.Check my RV weekend2 min · no loginEvening loadsNo hookupStation + panel2 nights
Six more situations are planned — coming next
Listed for transparency, not as working tools, and deliberately not clickable.
- UC-01 · plannedHome outage (whole household)A few hours to a full night, mixed household loads.
- UC-02 · planned72-hour family readinessMulti-day plan with a realistic recharge window.
- UC-04 · plannedRouter, laptop & PCSmall continuous loads, long duration, work continuity.
- UC-05 · plannedCPAP & medical-adjacentOvernight continuity with a conservative reserve.
- UC-07 · plannedJobsiteTool inrush, duty cycles, rough handling, noise limits.
- UC-08 · plannedOutdoor & campingPortability first, solar-only recharge realities.
Why it changes the decision
A capacity number cannot answer the three questions that matter.
1,000 Wh on the label is about 765 Wh you can plan on.
Conversion losses and a safety reserve come off before any runtime is shown. The gap between those two numbers is where most bad purchases are decided.
- 1,000 Wh
- on the label
- ≈ 765 Wh
- usable, planned
A compressor start is a pass/fail gate, not a bonus feature.
A unit with plenty of stored energy can still refuse to start a refrigerator. Only after that gate is duration counted — in usable hours, not label hours.
- several ×
- start vs running, briefly
- pass / fail
- peak gate
Duration means nothing if the daily cycle cannot close.
For 72 hours the unit must refill inside the window you actually have — wall, vehicle or solar — or the whole architecture is eliminated, however large it is.
- 72 h
- scenario
- daily loop
- must close
How it works
Three steps, one honest answer.
- 01
Declare your situation
Hours, the loads that must stay on, and what can recharge. No brand and no email.
≈ 90 seconds
- 02
Three gates are tested
Usable energy, the startup peak and the recharge loop — computed conservatively, shown on request.
Same inputs, same answer
- 03
Verdict — or abstention
A named product appears only when dated evidence covers your case. Otherwise you get “none of these fits” and the architecture to look at next.
Ranking fixed before commission
Guides and evidence
Read the reasoning before you trust the answer.
- Research tableXLSX · CSVRefrigerator outage sizing table15 published scenarios, the exact formula, and the gates capacity cannot answer.Open the table →
- Editorial guideBattery backup for a refrigeratorHours per kWh, the compressor gate, and when an installed system is the honest next step.Read the guide →
- Published methodRV sizing methodThe four equations behind the RV check, and the boundaries where it abstains.Read the method →
- Worked casesDecision casesFrozen inputs replayed against the live engine — including one that ends in a refusal.Open the cases →
Independent, dated, published
What you can hold us to.
Independence
No paid placement. A verdict set is ordered from your situation and the dated catalog before any commercial layer is applied; some eligible outbound links are affiliate links, and eligibility is decided before commission.
Dated data
Prices, stock and every volatile figure carry the date they were checked. Values that cannot be verified are marked unknown, never estimated silently.
Published method
Conservative rules, open to challenge, with corrections logged by date. Abstention is a valid output and is displayed as one.
Published by Alexis Marchais — engineer based in France, writing independently for a US audience. Editorial standards · Contact the publisher