How to Read a Power Station Spec Sheet

Capacity: watt-hours (Wh)

The first figure most buyers look at is capacity, stated in watt-hours (Wh). The U.S. Energy Information Administration explains that electricity is measured in units of power called watts, and a watt-hour is the amount of energy used when one watt runs for one hour. On a power station, the Wh figure tells you the total energy the battery can store, like the size of a fuel tank.

A listing may show the capacity as 1,000Wh, 2,000Wh, or 5,000Wh, and sometimes as kilowatt-hours (kWh), where 1kWh equals 1,000Wh. The higher the number, the more energy the station holds, but the listing does not tell you how long that energy will last for any specific device. Runtime depends on what you plug in, so the maker's page is the place to look for supported devices and any runtime estimates.

When a title says "expandable to" a larger number, that is the maximum capacity with extra batteries added, not the capacity in the box. A bundle that includes an extra battery usually states the total capacity in the title, so read the exact figure listed. For guidance on capacity bands, see the best portable power station guide.

Output: watts (W)

Output is stated in watts (W) and tells you how much power the station can deliver at one moment. The EIA notes that some devices need only a few watts, while others need more. On a spec sheet, you will see a continuous output figure, which is the steady power the inverter can supply, and sometimes a surge or peak figure, which is a short burst for starting motors or compressors.

A title may list several watt figures, such as 1,800W continuous and 3,600W surge. The continuous number is the one to compare between models, because it reflects what the station can run steadily. The surge figure is a temporary capability and does not mean the station can run at that level for long.

Output and capacity are different: a station can have a high watt-hour capacity but a lower watt output, or the reverse. Match the output to the devices you plan to run, and check the maker's page for the exact wattage each outlet supports. For a deeper look at output figures, read what is a 2000W inverter.

Battery chemistry: LiFePO4 and others

Most modern listings state the battery chemistry, often as LiFePO4, which stands for lithium iron phosphate. Some use the abbreviation LFP, and others write "lithium battery" without specifying the chemistry. The chemistry affects how the battery behaves, but this site does not make claims about lifespan or cycle count, because those figures are not in the listing data.

Read the maker's battery page for details about the chemistry and any care instructions. A listing that says "LiFePO4" is giving you a specific type of lithium battery, while "lithium battery" alone is a broader term. The chemistry is one factor in price, but it is not a promise of performance. To understand the difference between chemistries, see LiFePO4 vs lithium-ion long-term cost.

Solar input and panels

If a station supports solar charging, the spec sheet will list a solar input figure, usually in watts, and sometimes a voltage range. This tells you the maximum solar power the station can accept from panels. The listing may include a panel in the box, and the title might say "solar generator" to describe the bundle, even though it is a power station with a panel.

The EIA explains that solar energy comes from the sun and is captured by technologies like photovoltaic panels. On a power station, the solar input figure is a limit, not a promise of how fast the battery will charge. Charge time depends on sunlight, panel output, and the station's controller, so the maker's page is the source for that detail.

Panels sold separately are a different purchase, and a bundle with 2 panels will state the total panel wattage in the title. This site does not give charge time estimates, because that data is not in the listing. For more on solar input, read what is max solar input.

Ports and outlets

The spec sheet lists the types of ports: AC outlets, USB-A, USB-C, and 12V outputs like a car port. The number of AC outlets matters if you plan to plug in several devices at once, but the total output is still limited by the inverter's wattage. USB-C ports may support power delivery (PD) for laptops, and the listing will state the wattage of each port.

A 12V output is for devices that use a car-style plug, and some stations have a dedicated port for that. The listing will state how many of each port type the station has, so you can compare based on what you need to connect. The maker's page may list the maximum wattage for each port, which is not always on the listing. See power station output ports explained for more.

UPS and pass-through

Some spec sheets mention UPS (uninterruptible power supply) mode, which means the station can switch to battery power quickly if the wall outlet fails. The switchover time is sometimes stated in milliseconds, and a lower number means a faster switch. Pass-through means the station can charge and discharge at the same time, so you can run devices while the battery recharges.

These features are useful for a desk setup or a home network, but this site does not promise any uptime or protection. Read the maker's page for the exact switchover time and how pass-through works with your devices. For a comparison, see power station with UPS vs dedicated UPS.

Expansion batteries

If a station is expandable, the spec sheet will say so, and the title may include "expandable to" a maximum capacity. Expansion batteries are sold separately, and a bundle may include one, with the total capacity stated in the title. The expansion port is specific to the brand, so only compatible batteries will work.

Compare the base capacity and the maximum capacity to see how much you can grow later. The maker's expansion page will list compatible batteries and how to connect them. This site does not give runtime figures for expanded configurations, because that depends on the load. Learn more in expansion battery options.

What to pick for your situation

Questions

What does Wh mean on a power station?

Wh stands for watt-hours, a measure of the total energy the battery can store. The EIA explains that a watt is a unit of power, and a watt-hour is the energy used when one watt runs for one hour.

What is the difference between watts and watt-hours?

Watts measure the power output at a moment, while watt-hours measure the total energy capacity. A station can have a high Wh capacity but a lower W output, so both figures matter.

What is surge power on a spec sheet?

Surge power is a short burst of higher wattage that the inverter can supply for a brief moment, often for starting motors. The continuous output is the steady figure to compare.

How do I compare two power stations?

Compare the capacity in Wh, the continuous output in W, the battery chemistry, the solar input, and the ports. Read the maker's page for details not on the listing, such as runtime or charge time.