Watts to kWh & kWh to Watts Calculator

 

Watts to kWh and kWh to Watts calculators helps in finding out the energy consumption of a particular appliance or load when its power and time of use is given. Energy consumption helps in finding out the electricity cost generated due to an appliance.

Choose What to Calculate


Power :
W
Time :
hr
Formulas for Watts to kWh Calculation
E(kWh)
P(W) x
t(hr) / 1000
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Choose What to Calculate


Energy :
kWh
Time :
hr
Formulas for kWh to Watts Calculation
P(W)
1000 x
E(kWh) / t(hr)

What is kWh?

Kilowatts hour (kWh) is the unit used to express energy consumption of appliance or load.

What is Energy?

Energy is defined as the product of power and time. For constant value it is expressed as:

energy = power * time

For power expressed as a function of time, energy is expressed as:

Energy = Σ power(t) * tk
Energy = power(t) * dt

Here,

  • tf=final time
  • ti= initial time
  • tk= time at a given instant

it can be concluded that energy is the sum of the product of power and time.

Watts to kWh & kWh to Watts calculator parameter:

  • Choose what to calculate: Watts to kWh & kWh to Watts
  • if Watts to kWh selected: power in watts
  • If kWh to Watts selected: energy in kilowatt-hours
  • time: in hours

Converting Watts to kWh:

A general step for converting Watts to kWh is given as:

Step1: converting Watts to W-hr, by multiplying Watts with time (in hours). The quantity achieve is known as watts-hour (W-hr).

Step2: dividing W-hr by 1000 to get the required kWh.

Energy (E) =
power( in watts)*time(in hours) / 1000

Converting kWh to Watts:

A general step for converting kWh to Watts is given as:

Step1: converting kWh to W-hr, by dividing Watts by time (in hours).

Step2: converting W-hr to Watts, by dividing W-hr by time (in hours).

Power(P) =
energy (in kWh)*1000 / time (in hours)

Solved Example:

Watts to kWh conversion:

Consider the following data:

Given:

Power= 300 Watts

Time=3hr

Required:

Energy (E)=? (kWh)

Solution:

From Watts to kWh conversion formula:

Energy (E)=
3 * 300 / 1000
=0.9 kWh

kWh to Watts conversion:

Consider the following data:

Given:

Energy (E)= 2 kWh

Time=2 hr

Required:

Power=? (Watts)

Solution:

From kWh to Watts conversion formula:

P =
2 * 1000 / 2
= 1000 Watts