Portable chargers and power banks
What it is: A portable rechargeable battery is small and lightweight enough to tuck into a backpack or carry-on. This type of battery may have conveniences like built-in cables or multiple USB ports to maximize device compatibility.
What it powers: These batteries power small electronic devices, such as smartphones, laptops, tablets, headphones, flashlights, and lanterns. They range in capacity from 7.5 Wh (watt hours) to about 55 Wh. Our larger picks in the guide to portable chargers and power banks top out at about 36 Wh, which is enough to recharge a phone about three times.
Best for…
Pros: Portable chargers and power banks are the easiest and most affordable powering options, and they come in handy well beyond emergencies. You’ll appreciate them on your daily commute, during travel between airports and hotels, or anywhere there’s not a convenient outlet nearby. During an emergency, a fully charged power bank allows you to keep your phone on to check the news, get alerts, and stay in communication with neighbors or concerned out-of-town family members.
Cons: Power banks can’t compete with larger options when it comes to stamina or the types of equipment they can back up. Many of them are limited to USB-C or USB-A inputs and outputs. So they’re truly intended only for electronics; items with a standard plug — basically all housewares, except for maybe an LED lamp on a USB power supply — are excluded. You can find options with standard home outlets in the niche category of portable laptop chargers, which are slightly larger in power capacity, price, and physical size.
Good to know:
- They’re great for evacuations. Portable chargers and power banks are practical power sources when you’re on the go, and it’s ideal to have at least one per family member.
- They’re also great when you’re sheltering in place. Use a larger power source (like a generator or a portable power station) to recharge your power banks.
- And they will make the most of recharges. If you’re relying on a neighbor with a generator, or you’re traveling to access power, power banks can help maximize the value of those trips to recharge your gear.
Power-tool batteries
What it is: These rechargeable batteries work with drills, cordless mowers, and other power tools.
What it powers: These batteries work for tools and job-site gear, such as lights, fans, and radios. They range in capacity from roughly 140 Wh to over 750 Wh per battery. If you invest in an inverter, you can also power some small home electronics (such as lamps, fans, air purifiers, or a power strip for electronics).
Best for…
Pros: A power-tool battery is a particularly appealing option for people who already own a lot of cordless power tools for DIY work. With an inverter — which converts direct current (DC) to alternating current (AC) — you can use these batteries to power home devices that have standard 120 V outlets and USB ports. If you already own batteries from Ego, Ryobi, DeWalt, or Milwaukee, buying the inverter only is a cost-effective way to get backup power.
Cons: This isn’t the best approach for people who don’t already own a lot of cordless-tool batteries. Spreading the costs across multiple pricey, individual tool batteries is one of the more expensive ways (per watt) to get ample backup power. As with other portable battery options, with this one you’re limited to whatever charge level you have on your power-tool batteries when the disaster hits. So this could require some planning (or luck) if your power tools go through long periods of not being used.
Good to know:
- Bigger isn’t better. Some companies offer larger devices that combine multiple power-tool batteries to act as a small generator. But at this point, you’re better off with a portable power station for the price, power, convenience, and stability.
Portable power stations
What it is: This is a large rechargeable battery that can work indoors and be moved from room to room, offering a finite but ample power supply. Think of it as an electric generator that swaps gasoline for battery power.
What it powers: These devices can power laptops, modems, air purifiers, fans, and (intermittently) chest freezers. They range in capacity from about 500 Wh to 4,000 Wh, so they are 10 to 100 times more powerful than a good power bank.
Best for…
Pros: Portable power stations (PPS) have drastically improved over the past decade, thanks to battery technology driven by the rise of EVs. These silent, emission-free units can be safely used indoors to power lights and electronics. You can plug appliances straight into the unit, or you can install additional hardware to connect the PPS through your home’s breaker panel to use household outlets in an outage. When power is available, you can recharge the PPS via a wall outlet, or you can charge outdoors with a gas- or propane-powered generator during an extended outage.
Cons: With many PPS units, it can take a few hours to recharge several thousand watts, but improved electronics are chipping away at that limitation. Solar powering is an option, though that can also be sluggish without a large rooftop array. The EcoFlow NextGen 220W Bifacial Portable Solar Panel we tested drew about 170 watts per hour in peak sunshine; that means it would take at least 10 hours to fully recharge a 2,000 Wh PPS. You can combine multiple PPS units for more capacity, but doing so is really expensive. On a per-watt basis, a PPS costs more than a traditional generator. But the advantages on noise, emissions, and indoor use may make it worth the price.
Good to know:
- It’s good for apartment dwellers. A PPS is a good option if you have limited outdoor access and can’t use a gas-powered generator.
- The tech is improving. You could not find anything like today’s PPS models even five years ago, so you might soon see models that charge faster, cost less, or have some other ability worth waiting for.
Portable generators
What it is: It’s an internal combustion engine for electricity. The smallest options, at 1,000 to 2,000 watts, can be tucked in a trunk for a weekend trip. And the largest types, up to about 9,000 watts, usually live in a home’s garage (and driveway), ideally parked near the breaker panel.
What it powers: Two-outlet generators at the 2,000-watt level can simultaneously support small devices like phone chargers, fans, and lights, but not much more. A 4,000-watt generator can run larger appliances like chest freezers, mini fridges, and window AC units. With a generator this size or larger, you may consider connecting it via the home’s breaker panel, allowing for the backup of whatever you prioritize — your fridge, garage-door opener, the Wi-Fi and TV — or other designated circuits throughout your home.
Best for…
Pros: A portable generator can provide a power source capable of seeing you through an extended outage. There are a lot of feature-rich, well-priced generators that deliver some of the lowest price-per-watt figures you’ll find among all the backup power options you could choose.
Cons: You must use a generator in the right conditions — in a secure outdoor location, with a setup that minimizes the hazards of carbon monoxide emissions, noise, and exposure to weather. These small engines also require upkeep, and if you’re not regularly using the generator, that dormant period followed by sudden use can lead to a malfunction right when you need it. Storing gasoline requires adding fuel stabilizer, and accessing gasoline in the wake of a disaster can be problematic. Theft is also an issue, since a generator’s noise can draw attention, and areas affected by disasters are often targeted by looters in the aftermath.
Good to know:
- Combine it with electric backup. We compared models from Westinghouse, Honda, Generac, and Champion while researching our portable generator guide. And we came to believe a generator really works best in tandem with electric backup solutions (like a portable power station, power banks, and the like), as long as your budget permits multiple purchases.
- Look for dual-fuel engines. These engines can run on either gasoline or liquid propane (LP). Using LP slightly lowers the power capacity of most generators (relative to gasoline), but storing the tanks is easier.
- Determine the size you need. Deciding on a generator size can be tricky, so use a calculator to help determine what you need for your backup plan. We’ve found a 4,000-watt generator to be a sweet spot for many homes, and it often includes popular features like remote start and carbon monoxide minders.
- Back up home circuits. Generators that are around the 4,000-watt level and larger can often be wired into a home breaker panel by an electrician. Even backing up a few circuits can help you get through a long outage with less disruption.
Standby generators
What it is: This is a permanently installed generator, parked on a concrete pad near your breaker panel. It automatically kicks on in an outage and provides uninterrupted power.
What it powers: Residential models, ranging from 10,000 watts to about 26,000 watts, are usually large enough to back up a whole house.
Best for…
Pros: When connected alongside the regular breaker panel, a standby generator provides uninterrupted service through the home’s regular electrical system, and it shuts off when power is restored. Beyond convenience, a standby generator can head off additional damage related to a disaster: The sump pumps stay on to fight off a flood, the heat prevents frozen pipes in an ice storm, and the AC resists mold and mildew growth in post-hurricane heat. Most installations tie into the home’s natural gas service (if you don’t have that, you’ll be looking at a pricier install and a big propane tank). The dual-fuel versatility is attractive, but using LP often slightly decreases the standby’s power output.
Cons: Costs can add up. You may need to pour a concrete pad for the installation, and an electrician has to perform breaker-panel surgery to make the connections. You may need a permit for the work, and then there’s the four-figure price of the generator itself. Your property can also present obstacles: You generally need a flat space that’s about 10-by-10-foot square, with stable soil not prone to flooding; it should be close enough to the home to make practical gas and electric connections yet far enough from the home and windows to avoid carbon monoxide infiltration. Local codes may require it to be a certain distance from the property line, to protect your neighbors. If a disaster disrupts your natural gas service, you may not be able to use your generator when you need it most. Noise is also a drawback. Generac’s noise specs put the 24 kW model at 68 decibels, or “normal conversation” range, but there are enclosures and other sound-dampening measures to mitigate it.
Good to know:
- Standby generators have only gotten better. Generac and Kohler have a long history of reliable customer support. And in recent years they’ve both added new features to their generators: Wi-Fi connections, app-based controls, and system monitoring join other relatively recent innovations, including redesigned engines to suppress noise and improved performance on sensitive electronics.
- They’re more reliable over the long haul. Home battery-backup systems present a compelling alternative to standby generators, but for now this category can claim an edge on proven field reliability and serviceability over the long haul. A regularly serviced standby generator might last decades; that said, a competitive warranty like Generac’s covers you for only five years.
Home battery backup systems
What it is: These large, rechargeable batteries can run a home’s circuits during an outage. The installed systems connect to the home’s breaker panel, to restore power to the home during an outage. Unlike a standby generator, a battery-backup system can operate during non-outage conditions to optimize electricity use.
What it powers: These systems can power a whole house.
Best for…
Pros: Home battery-backup systems are powerful and offer versatility in powering a home during an outage. Many of these products bring together multiple large, PPS-style batteries to create systems that compete with (and even exceed) the capacities of common residential standby generators. You can also customize your configuration, buying only the batteries you need to power a portion of your entire home. Unlike standby generators, these systems can also be useful in non-outage situations. That’s where rooftop solar can play a part, by charging the batteries directly, so the home turns to grid power only when the batteries deplete.
Cons: These systems are expensive, and their costs often exceed those of standby generators if you spec out a system big enough to produce comparable loads of power. All of these products are fairly new, thereby raising as-yet-unanswered questions about their overall lifespan or troubleshooting as they age (the EcoFlow warranty is for five years on this system’s usual components). Prices should decrease as technology improves and market competition increases, and technical advances could make a costly purchase obsolete, or at least less cutting-edge, within the next five to 10 years.
Good to know:
- Consider add-ons. Support devices like EcoFlow’s Smart Home Panel 2 offer additional power management and monitoring capabilities. Switching between grid and battery power can take advantage of variable utility rates by recharging at off-peak hours and discharging during higher-priced periods.
- They’re good for solar-panel owners. When you pair these devices with a solar array, you can continuously offset a portion of your grid power consumption by switching between battery and grid sources and recharging via solar as the batteries deplete.
This article was edited by Jen Gushue and Christine Cyr Clisset.
