Watts and Watt Hours Explained Simply for First Time Buyers

If you are new to shopping for backup power, the specs can look confusing fast. Watts, watt hours, and capacity all sound similar but mean different things. Here is a simple way to understand them before you buy.

Watts measure power, not capacity

Watts tell you how much power something uses right now, or how much a power station can output at once. A device that uses 100 watts needs a power station capable of supplying at least that much at the same time.

Watt hours measure total energy stored

Watt hours tell you how much total energy a power station holds, similar to how a fuel tank holds gasoline. A 500 watt hour power station can run a 50 watt device for about 10 hours, or a 100 watt device for about 5 hours.

Putting it together

• Watts answer the question, can this device run at all
• Watt hours answer the question, how long can it run

When comparing power stations, watt hours is usually the number that matters most for figuring out how long your essentials will stay powered during an outage. Our GridBackup Home Kit lists both numbers clearly, so you can match it to what you actually plan to run.

Understanding these two numbers takes the guesswork out of buying, and helps you avoid paying for capacity you will never actually use.