4.5 Transportation Sector
The transportation sector is a major contributor to air pollution and greenhouse gas emissions. Green Technology offers crucial applications to overcome these issues and maintain environmental sustainability.
Learning Objectives
- Identify the socio-scientific issues and environmental impacts arising from the transportation sector.
- Explain the meaning and examples of green transportation.
- Describe the applications of Green Technology used to overcome socio-scientific issues in the transportation sector, including Natural Gas Vehicles (NGV), biofuels, and electric buses.
Hierarchy of Green Transportation Modes
The greenest modes are at the base; the least green mode is at the apex.
Short Explanation
What is green transportation?
Green transportation refers to any form of transportation that releases very minimal greenhouse gases or none at all, such as vehicles using renewable energy.
Motorised vehicles consume approximately 60% of the world's petroleum. They produce greenhouse gases like carbon dioxide and carbon monoxide that trigger climate change, as well as acidic gases that cause acid rain.
Why is this a problem?
95% of motorised vehicles used today run on petrol and diesel, which are obtained from petroleum. Because petroleum is a non-renewable source of energy, it can deplete.
How does Green Technology help?
Green Technology promotes green transportation modes, especially active commuting like walking and cycling, and using mass transit. It also introduces sustainable vehicle technologies including Natural Gas Vehicles (NGV using CNG or LNG), biofuels made from plant oils and animal fats, and clean electric buses.
Socio-scientific Issues in the Transportation Sector
The main environmental impacts caused by motorised vehicles.
Exhaust Fumes and Greenhouse Gases
Fumes emitted by vehicles contain gases such as carbon dioxide and carbon monoxide. Both are greenhouse gases that cause the greenhouse effect, leading to drastic climate change.
Depletion of Petroleum
95% of motorised vehicles used today run on petrol and diesel, which are obtained from petroleum. About 60% of the world's petroleum is used in the transportation sector. Because petroleum is a non-renewable source of energy, it can deplete.
Acid Rain
Dangerous gases emitted from vehicles can cause acid rain. Acid rain destroys plants, corrodes buildings and iron structures, and damages vehicle tyres.
Photochemical Smog
In July 1954, Los Angeles experienced major air pollution where the city was covered in photochemical smog caused by nitrogen oxide and hydrocarbons from vehicle fumes reacting with the surrounding air and ultraviolet rays from the Sun.
Application of Green Technology in the Transportation Sector
Three key applications that reduce pollution and petroleum dependence.
| Application | Key Features |
|---|---|
| Natural Gas Vehicle (NGV) | Natural gas vehicles run on either liquefied natural gas (LNG) or compressed natural gas (CNG). Vehicles that rely on petrol can be modified to use LNG or CNG. |
| Biofuel | Biofuel refers to fatty acid methyl ester produced from plant oils and animal fats. It is a renewable and more environmentally-friendly energy source currently used in Malaysia. |
| Electric Public Transportation | The Melaka State Government has implemented electric buses to carry passengers around the city as an initiative under Green Technology. |
Try to Answer First
Answer in your mind, then press “Check Answer”.
What are the two greenhouse gases emitted in vehicle fumes mentioned in the textbook?
What is the main source of raw materials used to produce biofuel?
What are two forms of natural gas used in Natural Gas Vehicles (NGV)?
Common Mistakes
- Thinking that Natural Gas Vehicles (NGV) emit zero emissions. While cleaner and modified from petrol engines, they still use natural gas, a cleaner fossil fuel alternative. 100% zero-tailpipe options are modes like walking, cycling, or fully electric vehicles.
- Assuming biofuel is a non-renewable fossil fuel. Biofuel is actually a renewable energy source produced from plant oils and animal fats (fatty acid methyl ester).
- Assuming single-occupant vehicles are at the base of green transport. Single-occupant vehicles represent the least green mode and sit at the top of the pyramid.
Concept Misunderstandings
Green transportation only means driving high-tech electric cars.
Green transportation includes any mode that releases minimal or no greenhouse gases, including simple zero-emission activities like walking (pedestrian) and cycling.
Acid rain only harms the atmosphere and clouds.
Acid rain directly damages terrestrial assets: it destroys plants, corrodes buildings and irons, and damages vehicle tyres.
Summary
- The transportation sector uses about 60% of the world's petroleum and is a primary driver of air pollution.
- Vehicle fumes produce greenhouse gases, namely carbon dioxide and carbon monoxide, which cause drastic climate change.
- Vehicle emissions also cause acid rain, which destroys plants, corrodes buildings and irons, and damages vehicle tyres.
- Green transportation prioritises pedestrians, bicycles, and public transit, with single-occupant vehicles as the least green mode.
- Green Technology applications include NGVs using LNG or CNG, renewable biofuels made from plant oils and animal fats, and electric public transport.
Short Activity
A. Objective Quiz
1 Which mode of transportation is located at the very base of the green transportation hierarchy?
2 What is biofuel chemically defined as according to the textbook?
B. Fill in the Blanks
3 Fumes emitted by vehicles contain carbon dioxide and monoxide, which are greenhouse gases contributing to drastic climate change.
4 Natural gas vehicles (NGV) use either liquefied natural gas (LNG) or natural gas (CNG).
C. Drag and Drop: Match the Concept to Its Description
Drag each concept to the correct description. On a phone, tap an answer first, then tap a matching box. Tap the Answer Choices area to return a selected item.
C. Match the Concept to Its Description
Write the correct concept next to each description.
| Description | Concept / Technology |
|---|---|
| 1. Destroys plants, corrodes buildings and irons, and damages vehicle tyres | |
| 2. Non-renewable energy source of which 60% is consumed by the transportation sector | |
| 3. Renewable energy made from plant oils and animal fats | |
| 4. Green public transportation adopted by the Melaka State Government |
Answer choices: Acid rain • Petroleum • Biofuel • Electric buses
