It is a PowerPoint of Electrical Power Consumption.

1. Electric Power Consumption
Unit-9 Electricity

2. Overview
To calculate total power consumption of a home, we need
to know the power of the each electrical equipment, the
number of equipment and time they run. This note
explains about the electric power consumption in our
house.

3. Electric Power Consumption
The total electric energy consumed by an individual
(especially houses) measured in kilowatt-hour is called
electric power consumption. All the power companies
install a meter in their customer's house so that they can
charge according to the electric consumption. Those
installed meters measure electricity on kilowatt-hour
(Kwh). In normal terms, we say 1 unit for 1 Kwh. It is
actually the amount of power used for a certain period of
time. For the easy purpose, we say an electrical appliance
of 1000 W consuming power for one hour will consume
1Kwh i.e. 1Kwh = 1Kw × 1hr.

4. 𝐏𝐨𝐰𝐞𝐫 𝐂𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧
= 𝐏𝐨𝐰𝐞𝐫 𝐂𝐨𝐧𝐬𝐮𝐦𝐞𝐝 𝐛𝐲 𝐀𝐩𝐩𝐥𝐢𝐚𝐧𝐜𝐞 × 𝐍𝐨. 𝐨𝐟 𝐀𝐩𝐩𝐥𝐢𝐚𝐧𝐜𝐞𝐬 × 𝐓𝐢𝐦𝐞 𝐨𝐟 𝐎𝐩𝐞𝐫𝐚𝐭𝐢𝐨𝐧
𝐏𝐨𝐰𝐞𝐫 𝐂𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧 = 𝐏(𝐢𝐧 𝐊𝐰) × 𝐍 × 𝐓(𝐢𝐧 𝐡𝐨𝐮𝐫)
𝐀𝐦𝐨𝐮𝐧𝐭 𝐭𝐨 𝐏𝐚𝐲 𝐨𝐫 𝐓𝐨𝐭𝐚𝐥 𝐂𝐨𝐬𝐭 𝐂
= 𝐏𝐨𝐰𝐞𝐫 𝐂𝐨𝐧𝐬𝐮𝐦𝐩𝐭𝐢𝐨𝐧 × 𝐏𝐫𝐢𝐜𝐞 𝐏𝐞𝐫 𝐔𝐧𝐢𝐭

7. So, to calculate total power consumption of a home, we
need to know the power of the each equipment, number of
equipment and time they run. Since all the appliances are
not run at the same time and same period of time it is
better to calculate power consumed by each appliance and
add all at last.

8. Example:
If a home has 10 tube lights of 30W that run for 4 hours daily, 5
television of 200W running for 3 hours daily, 2 irons 1000W 1 hour
weekly. Calculate total amount to be paid if the cost per unit is Rs. 7.
Solution:
Here,
𝑷𝒐𝒘𝒆𝒓 𝒐𝒇 𝑻𝒖𝒃𝒆 𝒍𝒊𝒈𝒉𝒕 𝑷𝟏 = 𝟑𝟎 𝑾 =
𝟑𝟎
𝟏𝟎𝟎𝟎
𝑲𝒘 = 𝟎. 𝟎𝟑 𝑲𝒘
𝑵𝒐. 𝒐𝒇 𝑻𝒖𝒃𝒆 𝒍𝒊𝒈𝒉𝒕𝒔 𝑵𝟏 = 𝟏𝟎
𝑻𝒊𝒎𝒆 𝑻𝟏 = 𝟒 𝑯𝒐𝒖𝒓𝒔
𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 𝒐𝒇 𝑻𝒖𝒃𝒆 𝒍𝒊𝒈𝒉𝒕𝒔 (𝑬𝟏) = 𝑷𝟏 × 𝑵𝟏 × 𝑻𝟏
= 𝟎. 𝟎𝟑 × 𝟏𝟎 × 𝟒
∴ 𝑬𝟏= 𝟏. 𝟐 𝑲𝒘𝒉

9. Now,
𝑷𝒐𝒘𝒆𝒓 𝒐𝒇 𝑻𝒆𝒍𝒆𝒗𝒊𝒔𝒊𝒐𝒏 𝑷𝟐 = 𝟐𝟎𝟎 𝑾 =
𝟐𝟎𝟎
𝟏𝟎𝟎𝟎
𝑲𝒘
= 𝟎. 𝟐 𝑲𝒘
𝑵𝒐. 𝒐𝒇 𝑻𝒆𝒍𝒆𝒗𝒊𝒔𝒊𝒐𝒏𝒔 𝑵𝟐 = 𝟓
𝑻𝒊𝒎𝒆 𝑻𝟐 = 𝟑 𝑯𝒐𝒖𝒓𝒔
𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 𝒐𝒇 𝑻𝒆𝒍𝒆𝒗𝒊𝒔𝒊𝒐𝒏𝒔 (𝑬𝟐)
= 𝑷𝟐 × 𝑵𝟐 × 𝑻𝟐
𝑶𝒓, 𝑬𝟐 = 𝟎. 𝟐 × 𝟓 × 𝟑
∴ 𝑬𝟐= 𝟑 𝑲𝒘𝒉

10. Similarly;
𝑷𝒐𝒘𝒆𝒓 𝒐𝒇 𝑰𝒓𝒐𝒏 𝑷𝟑 = 𝟏𝟎𝟎𝟎 𝑾 =
𝟏𝟎𝟎𝟎
𝟏𝟎𝟎𝟎
𝑲𝒘 = 𝟏 𝑲𝒘
𝑵𝒐. 𝒐𝒇 𝑰𝒓𝒐𝒏𝒔 𝑵𝟑 = 𝟐
𝑻𝒊𝒎𝒆 𝑻𝟑 = 𝟏 𝑯𝒐𝒖𝒓
𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 𝒐𝒇 𝑰𝒓𝒐𝒏𝒔 𝑬𝟑 = 𝑷𝟑 × 𝑵𝟑 × 𝑻𝟑
𝑶𝒓, 𝑬𝟑 = 𝟏 × 𝟐 × 𝟏
∴ 𝑬𝟑= 𝟐 𝑲𝒘𝒉
𝑻𝒐𝒕𝒂𝒍 𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒆𝒅 𝒃𝒚 𝒂𝒍𝒍 𝑨𝒑𝒑𝒍𝒊𝒂𝒏𝒄𝒆𝒔(𝑬)
= 𝑬𝟏 + 𝑬𝟐 + 𝑬𝟑
𝑶𝒓, 𝑬 = 𝟏. 𝟐 + 𝟑 + 𝟐 𝑲𝒘𝒉
∴ 𝑬 = 𝟔. 𝟓 Kwh

11. 𝑻𝒐𝒕𝒂𝒍 𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 𝒊𝒏 𝒐𝒏𝒆 𝒎𝒐𝒏𝒕𝒉
= 𝑬 × 𝟑𝟎 𝒅𝒂𝒚𝒔
𝑻𝒐𝒕𝒂𝒍 𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 𝒊𝒏 𝒐𝒏𝒆 𝒎𝒐𝒏𝒕𝒉 = 𝟔. 𝟓 × 𝟑𝟎
𝑻𝒐𝒕𝒂𝒍 𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 𝒊𝒏 𝒐𝒏𝒆 𝒎𝒐𝒏𝒕𝒉
= 𝟏𝟗𝟓 𝒖𝒏𝒊𝒕𝒔
𝑻𝒐𝒕𝒂𝒍 𝒂𝒎𝒐𝒖𝒏𝒕 𝒕𝒐 𝒃𝒆 𝒑𝒂𝒊𝒅 (𝑪)
= 𝑻𝒐𝒕𝒂𝒍 𝑷𝒐𝒘𝒆𝒓 𝑪𝒐𝒏𝒔𝒖𝒎𝒑𝒕𝒊𝒐𝒏 × 𝑷𝒓𝒊𝒄𝒆 𝑷𝒆𝒓 𝑼𝒏𝒊𝒕
𝑻𝒐𝒕𝒂𝒍 𝒂𝒎𝒐𝒖𝒏𝒕 𝒕𝒐 𝒃𝒆 𝒑𝒂𝒊𝒅 (𝑪) = 𝟏𝟗𝟓 × 𝟕
𝑻𝒐𝒕𝒂𝒍 𝒂𝒎𝒐𝒖𝒏𝒕 𝒕𝒐 𝒃𝒆 𝒑𝒂𝒊𝒅 𝑪 = 𝑹𝒔. 𝟏, 𝟑𝟔𝟓
Therefore, the total cost to be paid is one thousand three
hundred and sixty-five rupees.

12. Overview
To calculate total power consumption of a home, we need to know the power of
the each equipment, the number of equipment and time they run. This note
explains about the electric power consumption in our house.
Things to remember
• Power Consumption = Power consumed by appliance × Number of
appliances × 𝐓𝐢𝐦𝐞 𝐨𝐟 𝐎𝐩𝐞𝐫𝐚𝐭𝐢𝐨𝐧
• To calculate total power consumption of a home, we need to know the power of
the each equipment, the number of equipment and time they run.
• Meters measure electricity on kilowatt-hour (Kwh).

13. Thank you!
The End