Watt To Watt Hour

4 min read Jun 26, 2024
Watt To Watt Hour

Watt to Watt-Hour: Understanding the Difference

When it comes to measuring energy, two common units of measurement are watts (W) and watt-hours (Wh). While both units are used to express energy, they represent different aspects of energy consumption. In this article, we will explore the difference between watts and watt-hours, and how to convert between the two.

What are Watts (W)?

Watts are a unit of power, which is the rate at which energy is used or produced. In other words, watts measure the amount of energy consumed or produced per unit of time. For example, a 100W light bulb consumes 100 joules of energy per second.

What are Watt-Hours (Wh)?

Watt-hours, on the other hand, are a unit of energy, which is the total amount of energy consumed or produced over a period of time. Watt-hours take into account not only the power consumption but also the duration of time the energy is used. For example, if a device consumes 100W of power for 1 hour, it would have consumed 100Wh of energy.

Converting Watts to Watt-Hours

To convert watts to watt-hours, you need to know the duration of time the energy is used. The formula to convert watts to watt-hours is:

Watt-Hours (Wh) = Watts (W) x Time (hours)

For example, if a device consumes 500W of power for 2 hours, the total energy consumption would be:

Wh = 500W x 2h = 1000Wh

Real-World Applications

Understanding the difference between watts and watt-hours is important in various real-world applications:

Electricity Bills

Your electricity bill is usually measured in watt-hours (kWh). The cost of electricity is based on the total amount of energy consumed, which is calculated by multiplying the power consumption (watts) by the duration of time (hours).

Battery Capacity

Batteries are often rated in watt-hours (Wh), which represents the total amount of energy the battery can store.

Renewable Energy

In renewable energy systems, such as solar panels, the output is usually measured in watts. However, the total energy produced is calculated in watt-hours, taking into account the duration of time the system is generating power.


In conclusion, watts and watt-hours are two distinct units of measurement that are often confused with each other. Watts measure power, while watt-hours measure energy. Understanding the difference between the two is crucial in accurately measuring and calculating energy consumption in various applications. By using the conversion formula, you can easily switch between watts and watt-hours, ensuring accurate calculations and measurements.