The power consumption calculator calculates how units of electricity (kilowatt-hours or kWh) a device draws per hour, per day, per week, and month.

*How to compute electric consumption?*

You only need to know the wattage of the unit, and how long you run it at that wattage.

In the 2 examples below, you will also find how to calculate the electrical bill (cost of running an electric-powered device) using the average price of electricity ($0.1319 per kWh).

Here is how many watts do common household electric-powered devices use.

## Electricity Bill Calculation

Electric consumption depends on only one thing: the power of a device. On a specification sheet, you will find power or wattage (expressed in Watts).

The power consumption calculator above calculates how many kWh a certain device draws. For example, a 1,000 W device draws this many kWh if running for a certain period of time:

We can calculate how much impact this will have on our monthly electricity bill. For that, we need to know the price of electricity. Let’s presume that we run a 1,000 W air conditioner continuously for 1 month, with the average price of electricity being $0.1319 per kWh.

In the monthly bill, we will have to pay for 360 kWh of electricity. Here is how we can calculate the monthly electricity bill:

**Electricity Cost = 360 kWh * $0.1319/kWh = $47.48**

In short, running a 1,000 W unit continuously for a month will, on average, cost about $50.

Let’s look at the 2 examples where we will estimate electricity usage:

### Example 1: Electricity Usage Of 500W Washing Machine Running For 3 Hours

How much electricity will average wash use? Let’s presume that we have a 500W washing machine that runs for 3 hours. Just plug the 500W in the power consumption calculator above, and we get:

We see that the 500W washing machine uses 0.5 kWh per hour. In 3 hours, that is 1.5 kWh. To get the dollar amount, we need to multiply electric consumption by the cost of electricity. If we presume $0.1319 per kWh electricity cost, one wash will cost us:

**Electricity Cost = 1.5 kWh * $0.1319/kWh = $0.20**

### Example 2: Air Conditioner Power Consumption Per Month (3,000W AC Unit)

Summers can be hot. Let’s presume we install a 3,000W mini-split air conditioner (3,000W is equal to about 30,000 BTU). We will calculate how much will be running such a device cost per month if we have it turned on 24 hours per day. Realistically, we run an AC unit for about 8 per day, and we’ll calculate electricity expenditure for that as well.

Let’s use the electricity usage calculator above:

We see that every hour, a 3,000W device uses 3 kWh of electric energy. Running it for a whole month will burn 2,160 kWh of electricity. Let’s calculate the cost of that:

**Electricity Cost = 2160 kWh * $0.1319/kWh = $284,90**

As we can see, running it 24 hours per day will end up in a $284,90 increase in our monthly electricity bill. Realistically, however, we use it 8 hours per day, which will cost us less than $100 per month.

Fantastic, Thanks a lot

Respected Sir

When we use an electric heater with a rating of 1000 watts, how many units does it consume in eighteen hours?

Hi Bahadar, unit of electricity is usually a kilowatt-hour (kWh). 1000 watt electric heater consumes 1 kWh per hour. That 18 kWh in 18 hours, hope this helps.