- July 9, 2021
- Posted by: Dyaneshwar Nirmale
- Category: Digital Meters
What is Electrical Energy?
Electrical energy is electrical power consumed by a load for a period of time.
Electrical energy is defined by following equation:
Electrical Energy (kWhr) = Power (kW) x Time (hr)
Electricity used in Homes/offices is measured in terms of ‘unit’ by utilities 1 unit = 1 kWhr.
This means if 1kW load is ON for 1 hour then energy consumed is E = P xt = 1kW x 1hour = 1kWhr = 1 unit Consider the following example to clarify the concept
In the Fig 1, there are two lamps, one of 60W and another of 15W
The lamp of 6OW (0.06kW) load will take 16.67 hours to complete one unit (1 kWhr) E = 0.06 kW x 16.67 hr = 1 kWhr
The lamp of 15 W (0.015kW) load will take 66.67 hours to complete one unit (1 kWhr) E = 0.015 kW x 66.67 hr = 1 kWhr
From the above equations, it can be seen that 60W bulb requires 16.6 hours to consume 1 unit of electricity whereas 15 W bulb takes 66.67 hours for the same.
Therefore, the time required for consuming 1 unit of Electricity is lower when Power of the load is higher and vice-versa.
Conclusion Why measuring the energy matters
Energy measurement is a key requirement in calculating the cost of electricity consumed by homes, offices and industrial plants. Efficient energy measurement provides data that can aid in developing strategies to reduce energy consumption and cut losses.
