Recycling and limited resources
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Explainer Video
Summary
Recycling and limited resources
In a nutshell
The Earth has a finite (limited) supply of resources, which must be used sustainably. Sustainable means using resources in a way that minimises harm to the environment and leaves enough resources for future generations. Overuse of resources, lack of recycling and pollution-producing resources are issues in sustainability.
Resources
Resources are useful materials. Humans compete with other animals for natural resources, such as:
- Food
- Water
- Space
Fossil fuels
Fossils fuels are fossils, formed from the remains of dead organisms millions of years ago, which are used as fuel. Fossil fuels are natural resources. Coal and crude oil are fossil fuels that humans use for:
- Electricity
- Heat
- Engine fuel
Fossil fuels are unsustainable because they are non-renewable. This means they cannot be remade as quickly as we use them up - they take millions of years to make. Another reason why fossil fuels are unsustainable is that they release pollution, when they are burned. Pollution refers to harmful substances in the environment, which can harm humans, animals and plants.
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Dead vegetation and animals in fossil fuels | |||
Types of pollution
Sulfur dioxide, nitrogen dioxide, carbon dioxide and carbon monoxide are some of the most common air pollutants.
- Sulfur dioxide is produced when sulfur impurities in fossil fuels are burned, which causes acid rain
- Oxides of nitrogen, such as nitrogen dioxide, are produced when nitrogen impurities in fossil fuels are burned, which causes acid rain
- Carbon monoxide is produced when fossil fuels don't burn completely (incomplete combustion)
- Carbon monoxide is toxic to humans and animals because it prevents the blood from carrying oxygen
- Carbon dioxide is produced when fossil fuels burn completely (complete combustion)
- Carbon dioxide contributes to global warming and climate change
Renewable energy resources
Renewable energy resources are sources of energy that do not run out. These resources are therefore more sustainable than fossil fuels.
Examples
- Solar energy from the sun
- Wind energy from wind turbines
- Geothermal energy from the Earth's internal heat
Another benefit of these energy sources over fossil fuels is that they produce very little pollution, when being used. However, they can be less reliable than fossil fuels. For example, the speed and strength of wind is not always enough to produce energy in wind turbines. It can also be very expensive to produce and run the equipment for renewable energy resources.
 Solar panels are used to capture energy from the Sun. |  Wind turbines used to convert energy from the wind into electricity. |
Recycling
Converting resources, that have already been used, into other useful materials. Recycling is a sustainable practice and there are many materials which can be recycled.
Examples
- Metal
- Paper
- Glass
Materials that can be recycled are marked with the recycling symbol.
 Recycling symbol |
FAQs - Frequently Asked Questions
Why are fossil fuels unsustainable?
Fossil fuels are unsustainable because they are non-renewable. Another reason why fossil fuels are unsustainable is that they release pollution, when they are burned.
How were fossil fuels formed?
From the remains of dead organisms millions of years ago.
What are fossil fuels?
Fossil fuels are natural energy resources that humans use for electricity, heat and engine fuel. Crude oil and coal are examples of fossil fuels.