Form 4 Science: Chapter 4: Green Technology in ...

Form 4 Science:

Chapter 4: Green Technology in Sustainability of Nature

By Dr. You Li Ling

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Green Technology – the development and application of products, equipment and systems to conserve the environment and nature

Importance of Green

Technology

Solve the problem of

destruction of the environment

Reduce carbon emissions to

the environment

Improve human health and lifestyle

Conserve the use of natural resources by replacing it with the

use of renewable energy sources

Form 4 Science: Chapter 4 (Prepared by Dr. You Li Ling) 2

Four main pillars of natural green technology policy

• Energy • Environment • Economy • Social

Seven sectors of Green

Technology

Energy

Building

Waste and wastewater management

Transportation

Industrial and manufacturing

Agricultural and forestry

Information and communication technology (ICT)


Sectors Socio-scientific Issues Green technology

Energy sector • The use of fossil fuel- increase the content of greenhouse gases in the atmosphere – causes global warming and climate change

• Use of renewable energy (solar, hydro, biomass) - to replace fossil fuel in reducing carbon emissions

Waste and wastewater management

• Food leftover not properly disposed

• Chemical wastes and sewage disposed directly into rivers and seas that affected the aquatic life

• Management of solid waste resulting in an increase in greenhouse gases

• Sorting of household waste has been carried out to reduce the disposal of recyclable materials and reduce solid waste in landfills

• Run 5 R (refuse, reduce, reuse, recycle, recovery) to reduce solid waste

• Solid waste is treated with biological treatment process – used as renewable energy source (biomass) to replace fossil fuels

• Control the use of paper and prepare sufficient food for the whole family in order to prevent the food wastage


Global warming

• Green house effect causes global warming (gradual increment of the earth’s average temperature ) • Greenhouse gases into the atmosphere such as methane, nitrogen oxide, carbon dioxide and

chlorofluorocarbons (CFCs) - trap a lot more heat in the atmosphere • As carbon dioxide level in the atmosphere rises, carbon dioxide works as like the glass in greenhouse - It lets

the sunlight enters but stop some of the Earth heat escaping

• Global warming can change the climate of the earth, such as Extensive evaporation of water from the earth will causes droughts and dry weather (El Nino) Evaporation of water can speed up the formation of clouds and cause heavy rainfall; therefore, some areas

will experience floods and cold weather (La Nina).


Causes of global warming Open burning

Forest fire Deforestation

Combustion of fossil fuels in factories

Combustion of fossil fuels in vehicles

Ways to prevent global

warming

Reduce deforestation -Conserve and preserve

environment

Reduce the use of fossil fuels • -to Control excessive release of smoke

from vehicles and factories • -Use renewable energy • -Use public transports • -Car pooling • -Biking

Replanting trees -More trees to absorb carbon dioxide from

atmosphere -to equilibrate the oxygen

and carbon cycles in the air

Enforcing the law -Stop open burning

-Ensuring urbanization and

industrialization are well planned

Ensuring logging activities are planned and controlled to

prevent excessive destruction and loss of trees and animals


Recycle Bins


• Incineration is a waste treatment process that involves the combustion of organic substances contained in waste materials.

• Incineration of waste materials converts the waste into ash (organic matter), carbon dioxide and heat.

Incinerator


Wastewater Treatment System Malaysia


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Water is collected in a reservoir. Then, the water is purified before it is

distributed to our home.

Water purification process

1. Screening-separates leaves, rubbish and fish

2. Oxidation-removes unpleasant

smell and taste

3. Coagulation – alum coagulates suspended

particles whereas slaked lime neutralises the acidity

of water

4. Sedimentation- allows the lumps of impurities to settle

out at the bottom or removal

5. Filtration- a sand filter that removes algae, bacteria and

some chemical substances

6. Chlorination-chlorine kills harmful microorganisms and decolourisation the

water

7. Fluoridation –

Sodium fluoride compound is

added to prevent dental decay

Consumer

Dam

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Sectors Socio-scientific Issues Green technology

Agricultural and forestry

• Massive forest exploration for residential and agricultural purposes

• Open burning in agricultural areas causing air pollution

• Use of chemical fertilisers that cause pollution of the agricultural land

• The use of livestock manure and agricultural waste to produce compost

• The use of compost or organic fertiliser to increase soil nutrients

• Reduce the deforestation • Replanting of forest trees • Use biotechnology methods in

agriculture (hydroponic, aeroponic) to solve agricultural problems

Transportation

• Greenhouse gases released by motor vehicles are the biggest contributor that causes global warming and climate change

• Use the green transportation – walking, cycling and green vehicles (solar car, electric car, natural gas car, biofuel car)-to reduce greenhouse gases

• Replace oil fuel with biofuel resources

• Use public transport – LRT, monorail, MRT, buses


Eutrophication

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• Hydroponic system - The roots of plants take water from the pipes they grown in

• When plants take in water from soil – they also takes essential minerals that can be obtained from dissolved rocks, decaying plants & animals or artificial fertiliser

• In Hydroponic system – right amount of each minerals are added to the water

• Plants require minerals for healthy growth

Hydroponic System


• Aeroponics grows plants with their roots suspended in the air in a grow chamber (can get O2 for respiration)

• The plant roots are sprayed with a mixture of water and nutrients at high pressure with on/off intervals

• Well-circulating CO2 in the room allows further enhance growth.

• Aeroponics makes plants grow faster with less water and fewer nutrients.

• In soil, roots take in minerals by active transport (use ATP energy)

Aeroponic System

Form 4 Science: Chapter 4 (Prepared by Dr. You Li Ling)

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• Hydro, Solar, Wind, Wave,Tides, Geothermal, Biomass

• Fossil fuel (coal, petroleum and natural gas), Nuclear energy

Renewable energy Renewable energy - energy that is

collected from resources which will never run out and can be replaced

Non-renewable energy Non-renewable energy- energy that cannot

be replaced and will run out fairly soon


Biomass power station

Chemical energy (biomass) Heat energy (fire) Potential energy (high pressure gas expanding) Kinetic energy (spinning turbine and dynamo) Electrical energy (produced by the dynamo)

Biomass produces biogas (methane) and biofuel

(alcohol)


Production of biogas

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Wind power station

Kinetic energy (Wind rotates blades and turbine) Electrical energy

• Required large area (land) and strong and consistent wind


Gravitational potential energy (air is pushed out of the chamber when the water level in the chamber rises) Kinetic energy (rotates blades and turbine) Electrical

energy

Wave power station • Required consistent wave throughout the year

• Limited areas are available


Solar power station

Light energy (absorb by solar cells in solar panels) Electrical energy

Solar energy

• Advantages: does not cause pollution to environment and it is a renewable energy

• Disadvantage : this

energy is absent at night

• Solar cells – used in mini calculator, watches and cameras

• Solar panels – used in heating up water at homes and to generate electricity for satellites


Carbon footprint

Carbon offset

Waste

Gas

Water

Emission

Electric transport

Fuel

Recycling

• A carbon footprint – total amount of carbon released to the atmosphere as a result of individual activities, events, organisation, products, or communities

• As the carbon footprint grows longer, the higher the ratio of fossil fuel and release of carbon dioxide to the atmosphere

• Reduce carbon footprint: Carpooling, pull out plugs of electrical appliances when not in use, reduce water consumption, recycling waste at home, use energy save light (light emitting diode, LED and compact fluorescent lights, CFL), planting organic vegetable at home


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