1 Unit of electricity
Electricity consumed by household is measured in terms of Kilo watt-hour. For example, if you run your geyser for hot water which consumes 1000 watt (i.e. 1Kilowatt) for 1 hour then you have consumed 1000 watt-hour i.e. 1KWH or 1 unit of electricity.
For another example, if you run your T.V. which consumes 150W for 10 hours in a day then you have consumed 1500 Watt-hour i.e. 1.5KWH or 1.5 unit in a day.
Our all electrical appliances and machineries are rated in Watt (W). This is the unit of measurement of power that appliance or machine will draw when it will run to its full capacity. Power rating is mentioned on the name plate of electrical appliances.
Unit calculation formula
Unit consumed = Power x Time
i.e. Unit = Kilo Watt x Hr (kWh) (Kilo = 1000)
i.e. 1 Unit = 1000 W x 1 Hr
i.e. Unit consumed in a month = unit consumed in a day x 30 days
Average Consumption of Electricity for a Normal Household
| Appliance | Number | Wattage rating | Usage (Hrs/day) | Energy consumed/day | Unit/month (Unit per day x 30) |
| LED bulb | 4 | 9 | 6 | 216 | 6.5 |
| TV | 1 | 80 | 4 | 320 | 9.6 |
| Fan | 4 | 50 | 10 | 2000 | 60 |
| Computer | 1 | 300 | 6 | 1800 | 54 |
| Total | 439 | 26 | 4336 | 130 |
For a normal household, the consumption of electricity unit ranges between 100 – 500 units per month. The consumption of electricity depends on various factors, such as
- Star rating of appliance
- Hours of uses
- Age factor of machine or appliance
- Technology used in the appliance
ENERGY METER
The sum of all the unit consumed in a month is measured by energy meter which is connected to your electricity cable in meter cabin. The electricity company records this reading and bill is sent to you accordingly.
Total unit consumed in a month is indicated in your bill as energy consumed. Previous month meter reading and current month reading is displayed in the bill. The difference between these two readings are actual unit consumed by you in a given period (generally it is 30 days). Some electricity company does meter reading bimonthly.
Meter reader comes for the meter reading to your premises on fixed date. Some high value consumer’s meter reading is done remotely through Automatic Meter Reader (AMR).
When there is no meter reading in a particular month, past 3 months average reading data is taken as a monthly consumption and bill is sent accordingly.
Now we can read our energy consumption given on the electricity bill and calculate how much unit we can consume based on the rating and hours of usage of our household appliances.