Portable power stations are sold on big numbers: 1,500 watts, 3,600 watts, 7,200 watts. None of them tells you whether your refrigerator will still be running at breakfast.
Watts measure how hard a battery can push at any one moment. Watt-hours measure how much energy it holds. Mix them up and you can spend $2,000 on a box that goes flat by midnight, or on one with far more capacity than you’ll ever use.
I’m using Jackery’s lineup as the yardstick here because it covers the whole range, from roughly 1 kWh portable units to expandable whole-home systems. The sizing logic applies to any brand.
Decide what “emergency” means in your house
During a blackout, almost nobody is worried about the dishwasher. The list is shorter: the refrigerator, Wi-Fi, phones, a few lights, a laptop, and for some people a fan.
The refrigerator sets the clock. The CDC says food is generally safe for about four hours without power if you keep the door shut. A full freezer holds its temperature for around 48 hours. A battery that protects food and communications for a day is a very different purchase from one meant to run central air and an electric water heater.
Do the math yourself
It’s simpler than the marketing makes it look. Take the energy each device uses and multiply by the hours you need.
For the fridge, start with the yellow EnergyGuide label. Say it lists 600 kWh a year. Divide by 365 and you get about 1.64 kWh a day, or 1,640Wh. Inverters and batteries lose some energy as heat, and Jackery’s own refrigerator calculations assume about 85% usable efficiency. On that basis the fridge needs closer to 1.9 kWh of stored capacity for a full day.
Now add the small stuff. A 15W router running for 24 hours uses 360Wh. Four 8W LED bulbs for five hours add 160Wh. Phones barely register. Altogether you’re looking at 2.3 to 2.5 kWh before losses, and nearer 2.9 kWh after them. That is well above the 1 kWh the entry-level units hold, which is why a station that can start your refrigerator may still be unable to keep it going overnight.
What the Jackery sizes mean in practice
Explorer 1000 v2 (1,070Wh, 1,500W output, about 24 lb). It uses LiFePO₄ cells rated for 4,000 cycles to at least 70% capacity. Think of it as insurance for short outages. It will carry a refrigerator through part of a day alongside phones, lights and a router, but asking it to cover a full-size fridge and more for 24 hours is optimistic. Owners’ reports fit that: one ran a refrigerator for about ten hours and had roughly 30% left, and another uses it for fridge and home-network backup during outages that rarely last a full day.
Explorer 2000 v2 (2,042Wh, 2,200W, about 39.5 lb). This is where home backup gets genuinely useful. TechRadar’s reviewer ended up relying on it through repeated rural power cuts, running a fridge, office gear and some high-draw cooking appliances. If your goal is cold food, working internet, a few lights and charged devices until tomorrow, 2 kWh is the size I’d look at first. It still won’t run a whole house.
Explorer 3000 v2 (3,072Wh, 3,600W) and HomePower 3600 Plus (3,584Wh, 3,600W). This is the tier for homes where outages run overnight or the essentials list is longer. The extra output also covers coffee makers and microwaves that can trip a smaller inverter. The 3600 Plus can be expanded with extra batteries up to 21.5 kWh, so you can start small and add later. The price is weight: it’s about 77 lb, and the wheels are there for a reason.
What drains a battery fastest
A refrigerator cycles on and off. A 1,500W space heater doesn’t. Run one for an hour and you’ve used 1.5 kWh before conversion losses, which means a 2 kWh battery that could carry your fridge and router for most of a day is nearly empty in about an hour.
Kettles, hot plates, hair dryers, resistance heaters, portable air conditioners and electric water heating all behave the same way. Size the battery for your essentials, not for life as usual.
The big systems
The Explorer 5000 Plus holds 5,040Wh, outputs 7,200W and supports both 120V and 240V. With expansion batteries it can reach 60 kWh, and it can connect to a transfer switch to power selected household circuits. That’s a home energy system, not a portable battery. It makes sense if you face frequent multi-day outages or can’t tolerate generator fuel and noise. It’s hard to justify if your worry is a fridge full of food twice a year.
What owners like, and what they don’t
The most common praise is simplicity. You charge it, plug something in and read the display. Reviewers have consistently liked the V2 units for compact design, light weight for their capacity, fast charging and easy controls, and TechRadar scored the Explorer 1000 v2 highly for build quality. Jackery has about 4.4 stars on Trustpilot from just over 1,000 reviews, and many owners describe using theirs for refrigerators, home internet, cabins and storm outages. Some started with a small camping unit and moved up to a bigger one for the house.
The complaints are real, though. Trustpilot’s ratings are unusually polarized, with roughly two-thirds of reviews at five stars and about a fifth at one. The negative ones cite dead units, battery drain, shipping problems and warranty disputes. Jackery replies to most of them, but some customers describe slow escalation when hardware actually fails. Reddit shows the same split: years of trouble-free use for some, failed 1000 v2 units and poor warranty experiences for others.
I wouldn’t read that as proof the products are unreliable, because plenty of people use them happily. It does mean warranty support deserves more weight than it would on an ordinary gadget, since this is equipment you buy for the one night it matters.
A footnote on “UPS”
Jackery says the 1000, 2000 and 3000 V2 models have UPS functionality, with a transfer time of about 20 milliseconds. It also says plainly that this is not a zero-interruption UPS and shouldn’t be used for servers or workstations that need truly uninterrupted power. For a fridge or router that won’t matter. For a desktop you can’t afford to crash, it might.
Solar helps, but it won’t fix a small battery
A panel’s rating isn’t what you get all day. Clouds, season, shade and angle all cut into it. Jackery’s figures show this: the Explorer 2000 v2 accepts up to 400W of solar input, and with two 200W SolarSaga panels Jackery estimates about 7.5 hours for a full recharge under its test conditions. Real days will be worse. Buy enough battery for the outage you realistically expect, and treat solar as a way to stretch runtime.
Rough sizing guide
| What you want to protect | Capacity to start with |
|---|---|
| Phones, router, lights, laptop | 500–1,000Wh |
| Fridge and basic electronics for part of a day | about 1,000Wh |
| Fridge, router, lights and devices for roughly a day | 2,000–3,000Wh |
| Overnight outage, several appliances, a comfortable reserve | 3,000–4,000Wh |
| Multi-day outages or selected home circuits | 5,000Wh+ or an expandable system |
These are planning ranges, not guarantees. Check your refrigerator’s EnergyGuide label, put a plug-in watt meter on anything important, and decide whether you’re covering eight hours, a day or three.
Which one I’d pick
For occasional short outages, the Explorer 1000 v2. For getting a refrigerator, communications and basic household gear through a night, the Explorer 2000 v2. If outages are frequent or long, the HomePower 3600 Plus, because you can expand it rather than replace it. And if you need 240V circuits or whole-home integration, you’re shopping for something like the 5000 Plus.
Whichever you choose, start with a list of what you can’t afford to lose when the power goes out, and work out the capacity from that.