Said It Here

How to figure out what size portable power station I need

Calculating whether a portable power station can handle essentials like a fridge and freezer during an outage is difficult because of confusing math, unknown voltage details, and unpredictable power usage when appliances start cycling. Without clear data, people are left guessing whether a unit will actually meet their needs or if the investment is worth it.

What people tried

Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.

  1. 1
    Using an energy-measurement tool like a Kill-A-Watt meter to track actual power usage
  2. 2
    Testing the setup ahead of time
  3. 3
    Considering a petrol, propane, or natural gas generator instead
  4. 4
    Using an electric vehicle with bidirectional charging as a backup power source
  5. 5
    Buying a larger capacity unit upfront just in case the outage lasts longer than expected

In their words

Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.

DIY Stack Exchange1 person · December 2025

“Help me understand how well/poorly this portable power station might meet our needs. In a place where power outages are not uncommon, and we do not have a generator, I'm trying to decide whether to invest in something like this.”source ↗

“Have I done all that math correctly?”source ↗

“This makes no sense, right? The unit can output both DC (at two voltage levels) and AC. But am I right that without knowing what voltage these 100 ampere-hours are at, this value is useless?”source ↗

nuggethead · DIY Stack Exchange · 12 upvotes
r/homeowners1 person · September 2026

“seeing the outages around Long Island this weekend got me thinking about what we'd actually need to keep running if ours went out overnight: the fridge, a chest freezer, Wi-Fi, a few lights, and phones.”source ↗

“the current discount on the Ecoflow's delta 3 ultra plus has me wondering whether it makes more sense to start with 3kWh?”source ↗

“I don't know how much difference it would make once the fridge and freezer start cycling.”source ↗

Equal-Association818 · r/homeowners · 2 upvotes

Where this came up

People with this problem also raised