© Studydoctor 2009

Lesson 1: Patterns of energy use

Every day humans use different types of energy sources, such as fossil fuels in

cars, natural gas to cook with and electricity to make computers work. Energy

sources can be either a primary energy or a secondary energy source.

Primary energy source: This is an energy source that already exists in

nature, such as a fossil fuel (coal, natural gas, oil), which can be used

directly to get the energy you need. An example is using gas in your

boiler to produce heat.

Secondary energy source: This is an energy source which does not

exist in nature but is produced from a primary energy source, such as

electricity generated from the burning of fossil fuels. An example of this is

using electricity generated from coal to run your computer.

In your exam you may be asked to describe what a primary and secondary

energy source is.

Electricity is produced in a power station and reaches your home through a

network of electrical cables called the National grid. When you turn your

computer on, you require electricity from the national grid, this is a bit like

turning on a tap and getting water.

As you can imagine, the demand for electricity changes through the day and has

peaks and troughs. Believe it or not, the biggest demand for electricity is usually

during the advertisement breaks for popular TV shows like the X factor! Lots of

people decide to go and make a cup of tea during the break, meaning that

thousands of kettles suddenly need electricity from the national grid. This means

that the national grid must be able to supply the demand.

In your exam you may be asked how electricity reaches your home.

Sadly, generating electricity is neither efficient or clean. Most of the

electricity generated in the UK comes from fossil fuelled power stations, and this

releases carbon dioxide (CO2) into the atmosphere, adding to the problem of

climate change. Burning fossil fuels to produce electricity is also very wasteful,

and around half the energy from burning fossil fuels in power stations is wasted.

In your exam you may be asked what are the problems when producing

electricity from primary energy sources.

What you need to know:

1. What primary and secondary sources of energy are.

2. How energy use can affect the climate.

© Studydoctor 2009

In the future more and more people all over the world will want to use

electricity, which means the demand for electricity will increase. The problem is

the more electricity humans produce and use from primary sources such as fossil

fuels, the more CO2 will be released into the atmosphere, contributing to climate

change.

Governments are now trying to use alternative energy sources, such as

wind, solar and nuclear power, to produce electricity because they

produce no CO2.

In your exam you may be asked to name some alternative energy sources that

can be used to generate electricity without producing CO2.

Recap:

1. A primary energy source is a source that already exists, such as a fossil fuel.

2. A secondary energy source is generated from a primary energy source.

3. The national grid supplies energy, generated in power stations to your home.

4. Electricity produced from fossil fuels creates CO2, making climate change worse.

5. Governments are looking to use alternative energy sources to produce electricity.