Basic Electricity - Senior Secondary 1 - Transmission and distribution

TERM: 2^ND TERM

WEEK ELEVEN

Class: Senior Secondary School 1

Age: 15 years

Duration: 40 minutes of 5 periods each

Date:

Subject: BASIC ELECTRICITY

Topic: TRANSMISSION AND DISTRIBUTION

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

I.) Define transmission

II.) Define distribution

III.) Identify methods of transmission of electrical power

IV.) Differentiate between short and medium transmission lines

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures,

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

PRESENTATION

TEACHER’S ACTIVITY

STUDENT’S

ACTIVITY

STEP 1

INTRODUCTION

The teacher explains the meaning of transmission and distribution of electricity

Students listens attentively to the teacher

STEP 2

EXPLANATION

Teacher identify the methods of transmission of electrical power.

Teacher discuss the differences between short and medium transmission lines

Students exhibit attentiveness and active engagement

STEP 3

NOTE TAKING

The teacher writes a summarized

note on the board

The students

copy the note in

their books

NOTE

TRANSMISSION AND DISTRIBUTION

Transmission and distribution are two crucial stages in the delivery of electrical power from power plants to consumers:

Transmission involves the movement of large quantities of electricity over long distances, typically from power plants to substations. High voltage lines are used to minimize energy loss during transmission.

Distribution, on the other hand, involves delivering electricity from substations to homes, businesses, and other end-users. Lower voltage lines are used in this stage, and transformers are often employed to step down the voltage to safer levels for consumer use.

Methods of transmission of electrical power

Overhead Power Lines: Overhead power lines are perhaps the most common method of transmitting electricity over long distances. Conductors, usually made of aluminum or copper, are suspended from tall transmission towers to carry electricity.
Underground Cables: Underground cables are buried beneath the surface and are used in urban areas or environmentally sensitive areas where overhead lines are not feasible.
Submarine Cables: Submarine cables are used to transmit electricity across bodies of water, such as seas or oceans. They are typically used for international interconnections or to connect islands to mainland power grids..
High Voltage Direct Current (HVDC) Transmission: HVDC transmission is a method used to transmit large amounts of electricity over long distances with minimal energy loss. It involves converting alternating current (AC) to direct current (DC) at the sending end, transmitting the DC power over long distances, and then converting it back to AC at the receiving end.

Differences between short and medium transmission lines

Aspects	Short transmission lines	Medium transmission lines
Length	Typically less than 50 miles (80 kilometers)	Typically between 50 to 150 miles (80 to 240 kilometers)
Voltage	Usually operate at low to medium voltages (below 69 kV)	Operate at medium voltages (69 kV to 230 kV)
Power capacity	Lower power carrying capacity compared to medium lines	Higher power carrying capacity compared to short lines
Conductors	Typically use lighter conductors	Use heavier conductors to handle higher voltages and currents
Insulation	Generally less insulation required	May require more insulation due to higher voltages
Voltage regulation	May experience higher voltage drops and line losses	Generally have better voltage regulation and lower losses

EVALUATION: 1. Define transmission of electricity

Mention 4 methods of transmission of electrical power
Differentiate between short and medium transmission lines

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively