How Many Watts Do I Need in a Power Station? A Simple Load Guide
The single most common question I get, answered with a load calculator you can actually use at home.
How Many Watts Do I Need in a Power Station? A Simple Load Guide
I keep a paper logbook in my shop. Every test, every outage, every charge curve gets written down in pen. Last September, during a three-day grid drop after a windstorm, I ran my entire home office, the fridge, a freezer, and the modem off a single 2kWh unit. The notebook shows I pulled a steady 410 watts at peak, and the station barely broke a sweat.
The single most common question I get is some version of: how many watts do I need in a power station? Not amp-hours, not total capacity. Watts. People want a number they can hold onto. Here is the number: most households need between 1,500 and 2,000 watt-hours of capacity, and a continuous output of at least 1,800 watts. That covers a fridge, a freezer, internet, and lights for a day or two. If you want to run a space heater or a well pump, you are in a different class entirely.
I test these things personally. I run constant loads, log voltage and wattage every fifteen minutes, and graph the discharge curves. I thermal-image the cases at full load. If a manufacturer claims 2,010Wh, I want to see at least 1,900Wh on my meter before I say anything nice. The numbers below come from that testing, not from marketing pages.
The Short List
| Product | Price | Rating | Best For | My Verdict |
|---|---|---|---|---|
 Anker SOLIX S2000 |
$599 | ½ | Home office + fridge backup | The best 2kWh unit I've tested. Half the size of the competition. |
 Jackery HomePower 3600 Plus |
$1,899 | Whole-home backup with wheels | Stout, reliable, but the solar controller is a headache. | |
| EcoFlow Delta 3 Plus | $749 | Fast charging and app control | Solid mid-range pick, but the app is buggier than Anker's. | |
| Bluetti AC180 | $449 | ½ | Budget buyers who want LiFePO4 | Good value, but the 1,800W inverter is the ceiling. |
| Goal Zero Yeti 1500X | $1,199 | People who already own Goal Zero gear | Overpriced for the specs. You're paying for the brand. |
The Winner: Anker SOLIX S2000
I paid $599 for this on sale, and my logbook says "excellent deal" next to the entry. The S2000 delivers 2,016Wh of capacity and a 2,400W AC output. I ran a constant 500W load on it and got 3.9 hours before the low-voltage cutoff. That matches the math. The fridge test I did ran 35 hours on a single charge, which is what Anker claims, and that's rare.
The thing that got my attention is the size. At 36 pounds, it's half the weight of other 2kWh units I've tested. The Jackery 3600 is 77 pounds. The EcoFlow Delta 3 Plus is 52 pounds. The Anker is genuinely one-handed, which matters when you're hauling it from the garage to the kitchen during an outage. I carried it 50 yards to my van without stopping. That's not a workout, that's just carrying something.
The app is the best in the class. Charging schedules, time-of-use modes, and energy tracking with line graphs that are the closest thing to a logbook any app has built. I run my APC UPS into it as an extra buffer, which sounds redundant until you've had a brownout kill a BMS mid-cycle. Pass-through mode works as advertised: outputs stay live when AC is connected, battery kicks in if input voltage drops.
Here's my criticism. The front panel gives you almost no control. You're forced into the app for meaningful configuration, and if the app hangs, which it does occasionally, you're blind. For a piece of survival gear, that dependency bugs me. I want to be able to set charge limits from the panel, not just from my phone.
Cost per day math: if this unit lasts the advertised ten years, which is realistic for LiFePO4 chemistry with the 80%/90% charge limits enabled, $599 divided by 3,650 days is about 16 cents a day. That's cheap insurance for keeping your fridge alive.
[Check price on Amazon]
Best Value: Bluetti AC180
The AC180 is the budget pick, and it's honest about what it is. 1,152Wh of capacity and an 1,800W inverter. That's enough for a fridge, internet, and lights for about 12 to 14 hours, depending on the fridge's duty cycle. I measured a 4.2 cubic foot fridge drawing 85W average, so the math puts you at roughly 13 hours of runtime.
What I like: it's LiFePO4, it's 37 pounds, and it has a standard AC input. No proprietary connectors. The app is basic but functional. It does what it says on the box.
What I don't like: the 1,800W inverter is the ceiling. You can't run a space heater on this thing. Space heaters draw 1,500W continuous, which leaves you almost no headroom, and the runtime would be under an hour anyway. This is a fridge-and-phone station, not a whole-home backup. Know what you're buying.
At $449, it's 75% of the Anker's capacity for 75% of the price. That's fair. But you're giving up the app quality and the adjustable charge limits that extend cell life. If budget is the constraint, get the Bluetti. If you can stretch, get the Anker.
[Check price on Amazon]
What to Look For
Continuous output vs. surge output. The number on the box is surge, which lasts milliseconds. The continuous output is what matters. A fridge needs about 600W surge to start the compressor, but only 80-150W to run. A power station with 1,800W continuous output handles that easily. If your continuous output is below 1,000W, you're limiting yourself to phones and laptops.
Capacity in watt-hours, not watts. Watts tell you how much power it can push. Watt-hours tell you how long it can push it. A 2kWh station running a 500W load gives you four hours. That's the math. Don't buy a station with under 1,000Wh unless you're only charging phones and a laptop.
LiFePO4 chemistry. This is the only chemistry worth buying in 2024. The 15-year lifespan claim is real, but only if the BMS doesn't kill the pack first. The Anker S2000 uses prismatic LiFePO4 cells, which are safer and more robust than cylindrical. Check the spec sheet for cell form factor.
App quality. The app is part of the product. A station with a buggy app is a station with a broken UI, no matter how good the cells are. I've had firmware updates disable outputs mid-update during a minor outage. That was the opposite of comforting. Look for adjustable charge limits (80%/90%), which extend cell life, and make sure the app shows stale status indicators so you know when the data is old.
Solar charging is a top-off, not a full recharge. Anyone who tells you otherwise lives in Arizona. I tested two 200W panels on a Jackery in Wisconsin winter sun and got about 100W per panel. That's enough to offset drain, not recharge from empty. Budget for wall charging or a gas generator for real outages.
Frequently Asked Questions
How many watts does a refrigerator need? A standard 20 cubic foot fridge draws 1,200W surge to start the compressor, then settles to 80-150W running. Over a day, it cycles on and off, so average draw is around 50-80W per hour. A 2kWh station keeps it alive for roughly 24-35 hours. I tested this. It's true.
Can I run a space heater on a power station? Technically yes, but it's a terrible idea. A 1,500W space heater will drain a 2kWh station in under an hour and a half. A 3.6kWh station gets you maybe two and a half hours. Space heaters are grid appliances. Use a gas generator or a propane heater for heat.
Do I need the app? For basic use, no. Plug something in, press the button, it works. For charge limits, charging schedules, and energy tracking, yes. The Anker app is genuinely useful. The Jackery app hangs and shows outdated status without telling you it's stale, which is dangerous in an outage. Check the app before you buy.
How long will a LiFePO4 station last? The cells are rated for 3,500 cycles to 80% capacity. At one cycle per week, that's 67 years. Realistically, at daily use, you're looking at 8-10 years before you notice meaningful degradation. I won't speculate beyond that without a teardown or manufacturer datasheet to back it up.
Final Verdict
The 2kWh class is where the value is right now. $599 for the Anker S2000 is the sweet spot, and it's the one I keep in my van. If you need whole-home backup, the Jackery 3600 Plus is stout and reliable, but budget for the wheels because 77 pounds is not a backpack. If you're on a tight budget, the Bluetti AC180 gets you a fridge and lights for two nights.
For the love of god, don't buy a station with proprietary solar connectors unless you're ready to pay the accessory tax. And if you see a review that quotes marketing specs without a Kill A Watt on the output, ignore it. That's not reviewing, that's reading a spec sheet out loud.
I'm buying another S2000 on Prime Day if there's a sale. This is the kind of gear you want redundancy in. The notebook says so.