What do you need to run?
Add your fridge, router, lights and other essentials. Include operating hours and motor startup demand.
Open the outage planner →Home backup, worked out.
Keep the essentials on.
What needs power when the grid goes down? Build your load list, see the battery size you need, and compare systems that fit.
Free tools. No signup. Your assumptions, not a sales pitch.
YOUR ESSENTIALSExample · 24h outage
1.47 kWh needed at the appliances
Refrigerator · 120 W × 8h960 Wh
Wi-Fi router · 15 W × 24h360 Wh
LED lights · 30 W × 5h150 Wh
Battery capacity2.13 kWh
Starting-load screen845 W
90% AC efficiency, 10 W idle draw, 12% reserve. Appliance values are editable examples, not measurements.
Make this plan yours →15 sourced models · US specificationsEcoFlowAnker SOLIXBLUETTIJackery
From question to shortlist
Three steps. Fewer guesses.
Capacity, output and charging are different questions. Check all three before you choose.
Which battery fits?
Compare capacity, continuous output, voltage, expansion and weight across four brands.
Compare power stations →Can solar refill it?
Account for panel size, charging limits, sunlight and appliances using power while you charge.
Calculate solar recharge →Know what is behind the answer
Useful numbers. Visible limits.
We organise manufacturer specifications and build planning tools around them. We do not claim to have physically tested equipment unless a page explicitly documents it.
Read our method →- See the source
Product records link to manufacturer evidence and show when it was checked.
- Change the assumptions
Losses, reserve, operating time and sunlight are editable. An estimate is not a runtime guarantee.
- Choose by fit, not commission
The planner orders suitable base configurations by capacity. Our commercial relationships do not change the calculation.
Read before you buy
The decisions that matter
Battery size vs. power output
Why a large battery can still fail to start an appliance.
Sizing guide →Portable home backup
Outlets, expansion, transfer equipment and what to verify.
Buying guide →DELTA Pro vs. DELTA Pro 3
A closer look at capacity, 240 V and expansion differences.
Read the comparison →Researching rooftop solar instead? See the state guides and solar payback calculator.