"SLC21/WK6: Electricity bill and Electrical Cable, Circuit Breaker size Calculation."

Edited with canvas

An electric bill is often distributed by electricity provider to their customers detailing the amount of electricity consumed over a specific period which is typically a month like in the case of Nigeria. In the town where I am staying, there is a constant electricity supply, and I often receive electricity bills from the Abuja electricity distribution company every month. Whenever a bill is distributed there is usually a deadline for people to make payment failure to pay at the due date can lead to the disconnection of one electricity.

• A:

Write three key differences between XLPE and PVC cables.

Here I have shared three key differences between XLPE and PVC cables. Before looking at the differences XLPE stands for "Cross-Linked Polyethylene" whereas PVC stands for Polyvinyl Chloride Cables.

Key differences	XLPE	PVC
Dielectric Properties	XLPE provides superior dielectric strength which makes it very suitable for applications with high voltage.	PVC: Provides lower dielectric strength, which limits its use in applications with high voltage. This means it cannot be used in high-voltage applications.
Thermal Performance:	XLPE: The thermal stability of XLPE is much higher and it can operate at temperatures up to 90°C for continuous use and 250°C for short circuits.	PVC: The thermal stability of PVC is much lower and it is limited to 70°C for continuous use and 160°C for short circuits.
Longevity and Moisture Resistance	XLPE: Chemicals and resistance to moisture, with a longer lifespan and better performance in harsh environments	PVC It is susceptible to chemical degradation and moisture with a shorter lifespan.

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Write three key differences between single-core, two-core, and three-core cables.

Source

Here I have written three key differences between single-core, tow-core, and three-core cables:

Key differences	Single-Core	Two-Core	Three-Core
Number of conductors	It has only one conductor, which is typically used for simple circuit and single-phase connections	It has two conductors, which is usually for live and neutral connection in single-phase systems.	It has three conductors, which is often used for both live, neutral and earth connections in single-phase systems or systems with three phases.
Flexibility and Size	It is more flexible and slimmer, meaning it is easy to install in tight spaces	It is a bit bulkier and manageable, which is often used for domestic wiring	It is less flexible and bulkier, which is used in a system where there are additional phases of grounding.
Application	It is used when the installation is straightforward like connection equipment or power distribution.	It is best used for circuits or appliances without the requirements of an earth.	It is best used in systems or appliances that require an earth wire for safety.

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Write about peak and off-peak hours in your country.

My country is Nigeria, and in Nigeria peak and off-peak hours for the usage of electricity are determined by the energy demand pattern in the country, which is influenced by commercial, industrial activities, and residential. For managing energy consumption and costs, for Nigerians who are using prepaid meters with varying tariffs, it is important for the classification of peak and off-peak hours.

Peak Hours in Nigeria

In Nigeria Peak hours time begin from 6:00 AM - 10:00 AM and 5:00 PM - 10:00 PM

Usually these hours, there is high demand due to residential activities that are carried out by people in the morning. Like for example, during morning hours Nigerians pump water and cook, whereas during evening, cooling, entertaining, and lighting are used the most. Also, during these hours industrial and commercial facilities contribute to the load which time of use metering electricity tariffs is much higher.

Off-peak Hours in Nigeria

In Nigeria, Off-peak hour time begins from 10:00 PM - 6:00 AM and most times in hot afternoon 12:00 PM - 4:00 PM.

Usually, in these hours the demand or usage of electricity is lower as most businesses and households reduce their energy consumption during the non-active period and night hours. Also, tariffs are lower as said before to encourage people to carry energy-intensive activities such as washing, ironing, and other activities.

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B. Calculate your house load and prepare the electricity bill for November 2024 by following Example 1.

Source

Based on the example that has already been given by the professor which is what I will be following I have shared the electricity that is consumed.

In my house, three lights of 30 watts are on for 4 hours per day, four fans of 70 watts are on for 5 hours per day, and a room heater of 70 watts is on for 3 hours per day. Our electricity company's electricity bill per unit is 0.14 Steem. How much will my electricity bill be in November 2024?

Solution:
Formula to calculate electricity consumption: Watts * Number of loads * Hours

Electricity consumption of the lamp per day:
= Watts * Number of loads * Hours = 30 * 3 * 4
= 360 WH
= 0.36 KWH [1 KW = 1000 Watt]

Electricity consumption of the Fans per day:
= Watts * Number of loads * Hours
= 70 * 4 * 5 hours
= 1400 WH
= 1.4 KWH

Electricity consumption of the room heater per day:
= Watts * Number of loads * Hours
= 70 * 1 * 2 hours
= 140 WH
= 0.14 KWH

Total electricity consumption in a day:
= Lamps + Fans + Room heater
= (0.36 + 1.4 + 0.14) KWH
= 1.9 KWH
= 1.9 Unit[ 1 KWH = 1 Unit]

Total electricity consumption for November 2024:
= Total electricity consumption in a day * 30 [November Month= 30 Days]
= 1.9 * 30
= 57 KWH
= 57 Units

Electricity Bill Per unit = 0.14 Steem
Total electricity bill for November 2024:
= Total electricity consumption for November 2024 * Per Unit cost
= 57 * 0.14
= 7.98 Steem(Ans.)

From the above calculation, it means my electricity bill for November 2024 will be 7.98 STEEM

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C. Calculate the total electricity bill with the HT meter values ​​given in Example 2 and design an electricity bill in Excel.

For me to calculate the total electricity bill and design an Excel, I will have to follow the steps that I have shared below.

HT Meter Reading:

Date	R1(Peak)	R2(Off Peak)	Total KWH
01-11-2024	2625.20 KWH	9692.81 KWH	12318.01
30-11-2024	2665.26 KWH	9825.21 KWH	12490.47

Peak Rate	1.5 Steem
Off-Peak Rate	1.0 Steem

Formula:

R1(Peak)=(2665.26-2625.20)KWH * 18000= 721080
R2(Off Peak)=(9825.21-9692.81)KWH * 18000= 2383200

Total KWH = R1 +R2 = 721080 + 2383200 = 3104280

Total KWH = (12490.47-12318.01)KWH = R1 + R2

Total Electricity Bill = R1(Peak) * 0.15 = 721080 [Per Unit cost = 0.15 Steem(Peak)]

Total Electricity Bill = R1(Peak) * 0.15 = 721080 * 0.15

Total Electricity Bill R1(Peak) = 108162 [Per Unit cost = 0.15 Steem(Peak)]

Total Electricity Bill = R2(Off Peak) * 0.10 = 2383200 [Per Unit cost = 0.10 Steem(Off-Peak)]

1 KWH = 1 unit

Designing the Excel Sheet

My Electricity Bill Design

Interpretation

• I open Excel and enter the figures in the Excel before I then use formulas for automatic calculation:

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D. Figure out the cable and circuit breaker sizes you need to set up a 20 ampere, 220 volts, and power factor (PF) 0.9 washing machine at home.

For us to set up a 20A, 220V washing machine with a power factor (PF) of 0.9 at home, I will need to determine the appropriate cable and circuit breaker sizes based on the electrical load.

Using Formula

P= V * I * PF

P = 220V * 20A * 0.9 = 3960W (3.96 kW)

For the cable size and circuit breaker to be determined we will have to divide the total power by 3.

P = 3960/3 = 1320Watt.

From the above, it means a 1320-watt load would need a 2.00 RM cable and C10 (10 Amp) circuit breaker for the washing machine.

I am inviting; @dove11, @simonmwigwe, and @ruthjoe

Cc:-
@mahadisalim