# What is the relationship between AMPS and WATTS?

Feb 23,2020 | Will Wilkerson

In the previous blog we went over what a watt was and how to calculate what you need in watts for your solar system. Amps have a similar part to play in the equation, but AMPs are the output that you measure a device needing. Unlike your lightbulb that will already tell you how many watts you need your devices like your cell phone and refrigerator have to be calculated. You have to take the equation from the last blog Watts = Volts (V) x Amps (A). If your refrigerator is 100V and 10 amps you need 1000w.

## AMPS AND AMP HOURS

Watts are the amount of force that can be applied to an outlet. Just like you needed to calculate watt hours you will need to calculate amp hours. Amps will appear as an A, and are the rate of the current, aka how fast it is flowing. How fast the electricity is moving in the wire is amperage/amps.

Amp hours will appear as Ah and is the amount of energy charge in a battery that will allow one amp of current to flow for one hour. For example, 10 amps for 2 hour equals 20 amp hours (10A x 2 hours = 10Ah). If you think of it like water then it is like how much water would fill up a bucket in 2 hours. While water is measured in gallons or liters, electricity is measured in amp hours.

Batteries are generally rated in both volts and amp hours so using the equation is important. The amp hour rating tells you how much energy the battery can store. A 200Ah 12V battery stores twice as much energy as a 100Ah 12V battery. Just like a 2-gallon bucket can hold twice as much water as a 1-gallon bucket.

Comment below about what you want to learn about next or how you understood this better.