# kwh vs watts: What Is the Difference?

## kWh Vs Watts Overview

Contents

Kwh vs watts: What Is the Difference? As far as electricity usage is concerned, knowing the difference between a watt (W) and kilowatt-hour (kWh) is important if you want to have better control of your electricity bill. You cannot save energy if you don’t know how much energy an appliance with a specific power rating would consume if it runs for a certain amount of time.

### Watt vs Kilowatt-hour

To know the difference between a watt and a kilowatt-hour, you would have to differentiate between power and energy first. In the simplest terms, power is the rate of consumption or production of energy, whereas energy is the capacity of a physical system to generate or perform work.

In this case, watt (W) is the unit of power, whereas kilowatt-hour (kWh) is the unit of energy. You can use the power rating of an appliance (in kilowatts) multiplied by the hours of usage of the appliance to determine how much energy the appliance will have used (in kWh) within a specific amount of time.

In conclusion,

The main difference between watts and kilowatt-hours is that a watt is the unit of power, whereas a kilowatt-hour is the unit of energy. When calculating your electricity bill, your supplier will be interested most in the kWh value, as this is the value that is multiplied by the cost per kWh to provide the total cost of electricity for a given period.

## kWh Formula for Manual Calculation of Energy Consumption

### kWh formula

When calculating your monthly or yearly electricity bills, the most important factor will be the total amount of energy that you have used over that period. As long as you know what values are required and how to derive the energy consumption from these values, there are different ways to evaluate the total energy used.

However, you can use formulas as an easy and direct way to calculate the kWh value that is required when evaluating your electricity bills.

## What are the formulas used to calculate kWh?

There are two formulas that you can use to calculate energy consumption. The most ideal formula to use will depend on whether you are working with watts or kilowatts. When working with watts, the energy (E) in kilowatt-hours (kWh) is gotten by multiplying the power (P) in watts (W) by the period (t) in hours (h) divided by 1000 watts per kilowatt. Here’s the formula:

E (kWh) = P (W) x t (h) / 1000 (W/kWh)

When working with kilowatts, on the other hand, the formula is easier and shorter. To calculate the total energy (E) in kilowatt-hours (kWh), you are only required to multiply the power (P) in kilowatts (kW) by the period (t) in hours (h). Here is the complete formula:

E (kWh) = P (kW) x t (h).

In conclusion,

The formulas shown above will come in handy when calculating the energy that your appliances consume over a specific period of time. It’s, however, easier to calculate the energy in kilowatt-hours when working with kilowatts as compared to when working with watts. Nevertheless, once you have the kWh value, it’s easier to determine your electricity cost whether on a daily, monthly, or yearly basis.

## How to Convert kW into kWh

If you are the one who pays the electricity bills in your home, it’s more than likely that all your bills are based on kilowatt-hour (kWh) usage. The problem is that not all of us know much about this unit of energy. However, since this measurement dictates how much we pay at the end of every month, it’s a good idea to know how we can derive it from the unit that the majority of homeowners are familiar with: kilowatts (kW).

### Deriving kWh from kW

In the simplest terms, a kilowatt-hour is simply the amount of energy that will be used if you left a 1,000-watt device running for one hour. In that light, kilowatt-hours can be thought of as the power (kW) used over a certain period of time, expressed in hours. As such, to derive kWh from kW, all that we have to do is multiply the kW rating of a device by the number of hours that it has been used.

Let’s say that we’ve used a 1,400-watt oven for half an hour. To calculate the energy used in kWh, we will first convert the watts into kilowatts by dividing them by 1,000 (1400/1000 = 1.4 kW). Next, we can convert the kW into kWh by multiplying the kW by the number of hours that the appliance has been used (1.4 x ½ = 0.7 kWh).

Final word,

To convert kW into kWh, we will have to know the kW rating of an appliance, as well as the number of hours that it has been used. That’s because energy (kWh), is power (kW) used over time (h). Once you know how to determine how much energy the appliances that you are using consume over time, it will be easier to confirm the accuracy of your bills.

## Using a kWh Cost Calculator to Determine Your Electricity Bills

There are various reasons why you might want to calculate the cost of the electricity that you have used, whether on a monthly or yearly basis. By doing so, you can make energy-saving decisions where possible to cut down on unnecessary costs. You can opt to do the calculations either manually or automatically using an online electricity cost calculator.

### Manual calculation

You can calculate your electricity bill using two formulas. The first one will help you to determine the energy consumption while the second one covers your electricity cost. To calculate the Energy in kilowatt-hours (kWh) per day, use the following formula:

``E (kWh/day) = P (W) x t (h/day) / 1000 (W/kW)``

Next, you will have to calculate the electricity cost using the following formula:

``Cost (\$/day) = E (kWh/day) x Cost (cent/kWh) / 100 (cent/\$)``

### Automatic calculation

Instead of calculating your electricity costs manually, you can use the many electricity bill calculator tools that are available online. To use the calculators, the values that you need to know are:

``````Energy price
Power consumption
Usage time``````

Once you’ve inputted these values into the cost calculator, the calculator will automatically display the yearly cost for the electricity that you use.

In conclusion,

Electricity cost calculation has never been much easier with the introduction of online electricity cost calculators. If, however, you are a math fan, you can always use the manual method to calculate your daily electricity bills. By doing so, it will be easier to confirm whether you are receiving accurate bills at the end of every month.

## How Much Energy Will a 100-Watt Light Bulb Consume in 24 Hours?

As far as electricity consumption is concerned, power and electrical energy are two vital elements. Power, denoted by watts, is the rate per unit time, by which electrical energy gets transferred by an electric unit.

Electrical energy, on the other hand, is the capacity of an electrical circuit to do work by creating an action, which can be electrical, thermal, mechanical, and more. Electrical energy is mainly denoted by watt-hours (Wh), or kilowatt-hours (kWh). In the majority of cases, however, it is represented using kWh.

### So, how much electrical energy can a 100-watt bulb consume in 24 hours?

If you want to determine how much energy a 100-watt bulb would use up if left operating for 24 hours, you would first have to convert the watts into kilowatts. In this case, 100 watts into kilowatts would be (100/1000 = 0.1 kW).

To get the energy consumed in a specific period of time, we multiply the power by the number of hours. In this case, if you left the bulb on for 24 hours, the total energy used would be (0.1 x 24 = 2.4 kWh).

With this value, you can then calculate how much it would cost to run the bulb for those 24 hours, depending on the individual rates charged by your supplier.

In conclusion,

The amount of energy that a 100-watt light bulb will consume when left on for 24 hours can easily be calculated by multiplying the wattage of the bulb by the number of running hours. Since electrical energy is mostly denoted using kWh, you will have to divide the value that you’ve gotten in the first step by 1,000 to convert the watts per hour (Wh) value into kilowatts per hour (kWh).

## How to Convert kWh/year to Watts

A kilowatt-hour (kWh) is the most important unit when monitoring electricity consumption whether in a commercial or residential setup. The kWh unit is presented in calculations, not something more basic, simply because it is reliant on two variables: the wattage of an appliance, and the number of hours that you use the appliance. When expressed yearly, a kWh becomes a kWh/year.

### Converting kWh/year into watts

To convert one kWh/year into watts, you need to divide one by 12, to get the kWh/month value which should be (1/12 = 0.0833). If we focus on a month of 30 days, you can divide the value further by 30, to get the kWh/day value which would be (0.0833/30 = 0.0028).

With 24 hours in a day, you can break down the kWh/hour value into kW if you divide it by 24 (0.0028/24 = 1.1667 x 10-4). That’s because (kWh/h) would cancel out the “hour” unit, leaving us with kW alone. We can then get the watts value if we multiply the kW value by 1,000 (1.1667 x 10-4 x 1000 = 0.1167 watts).

However, this figure is inexact due to the rounding off. As such, the more accurate way to get calculate the number of hours in one year would be to multiply the number of days in a year (365.25) by 24, which would give us 8,766h. To convert 1 kWh/year into kilowatts, we can then divide the 1 kWh by 8766 h, to get (1.14077 x 10-4).

Finally, we will multiply the kW value by 1,000 to get the watts value (1.14077 x 10-4) x 1,000 which would give us 0.114077 watts. As such, one kWh/year converted into watts is 0.114077 W.

Conclusion,

Deriving watts from a kWh/year value is quite easy. All you have to do is divide the value by 8,766 and then multiply it by 1000. This may not be something that you do so frequently, but it can give you an idea of the wattage of the appliance that has used a specific number of kWh per year.

## How Many watts is a Kilowatt-Hour?

A kilowatt-hour (kWh) is simply a measure of energy that can be calculated as the amount of energy that a 1,000-watt-rated appliance uses in one hour. Contrary to what many energy users think, it’s not the number of kilowatts that an appliance uses in an hour.

### Converting watts to kWh

To save energy, you may want to know how many kilowatt-hours you use every month. Because the majority of home appliances are not rated in kilowatts, however, you will want to convert the watts into kilowatts, and then calculate the kWh value.

Since a kWh is the amount of energy that you would use when you keep a 1,000-watt device running for an hour, that means that a 100-watt bulb would have to be turned on for 10 hours to use 1 kWh of energy. On the other hand, a 2000-watt appliance would take only half an hour to use the same amount of energy.

So, how many watts is a kilowatt-hour? There is no definite answer for this. You can say that a kilowatt-hour is 1000 watts used for an hour, but it’s also 100 watts used for 10 hours. The answer lies in the wattage rating of the appliance that you are using, and how long you will be using it.

In conclusion,

A kilowatt-hour (kWh), is different from a kilowatt (kW) and watt (W), in that a kWh is a measure of energy whereas a kW and W are both measures of power. The connection between these three units, however, is crucial to anyone who wants to know how much energy they are using within a specified period.

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