KS3 Physics 7I Energy Resources

7I Energy Resources The nature of energy Energy resources Fossil fuels Contents 7I Energy Resources The nature of energy Energy resources Fossil fuels Summary activities

Different types of energy There are many different types of energy: thermal light sound elastic gravitational kinetic electrical chemical nuclear Can you think of examples of each type of energy?

The nature of energy

Energy transfer Energy can be changed from one form to another. For example: Chemical energy in food is converted to thermal energy and kinetic energy by our bodies. Gravitational energy in a ball is converted to kinetic energy when it falls to the ground. What other energy transfers can you think of?

What is the energy transfer? What energy transfer takes place in each device? burning match portable torch microphone radio television catapult mobile phone car chemical → heat and light sound → electrical electrical → sound and heat electrical → sound and light and heat elastic → kinetic and heat chemical → sound and microwaves (EM radiation) and heat chemical → kinetic and sound and heat In all these transfers the energy is not lost, it is conserved. Energy cannot be destroyed or created.

Converting energy activity

7I Energy Resources The nature of energy Energy resources Fossil fuels Contents 7I Energy Resources The nature of energy Energy resources Fossil fuels Summary activities

Using energy Humans use chemical energy (from food) to live and function. However, in a modern society we also use large amounts of energy from other sources. Can you think of some activities requiring energy? traveling and communicating over long distances; controlling our environment, e.g. air conditioning/heating; manufacturing and building many kinds of materials and products, e.g. roads, cars, buildings, prepared food. Where does the energy for these types of activity come from?

Energy resources in the UK Energy resources can be divided into two types: non-renewable (e.g. coal, oil, nuclear and natural gas); renewable (e.g. wind, solar and hydroelectric power). Teacher’s Notes Data based on the consumption of primary fuels in the UK in 2003 from the dti Digest of UK Energy Statistics 2004. Web reference: http://www.environment-agency.gov.uk/commondata/103196/energy1? referrer=/yourenv/eff/resources_waste/energy/

Non-renewable energy resources Oil, coal and natural gas are examples of fossil fuels. They were formed from biological deposits over the course of millions of years. oil coal natural gas There is a finite amount of fossil fuels on the Earth and they will eventually run out. Once fossil fuels are used they cannot be regenerated and used again, so they are called non-renewable.

Renewable energy sources Renewable energy resources will not run out because they can easily be regenerated. Examples of renewable energy resources are: wind power solar power tidal power biomass Only 2% of the UK’s energy comes from renewable sources. Why do you think this is?

Renewable or non-renewable?

Energy and the Sun The Sun is the original source of most energy resources. Plants store the Sun’s energy through photosynthesis. Plants are eaten by animals, which are then eaten by other animals, so the energy is passed on.

Energy resources from the Sun coal waves oil biomass wind food natural gas

7I Energy Resources The nature of energy Energy resources Fossil fuels Contents 7I Energy Resources The nature of energy Energy resources Fossil fuels Summary activities

Fossil fuels

How coal was formed About 300 million years ago, trees and other plants photosynthesized and stored the Sun’s energy. Dead plants fell into swampy water and the mud prevented them from rotting away. Over the years, the mud piled up and squashed the plant remains. After millions of years under this pressure, the mud became rock and the dead plants became coal.

Coal formation

How oil and gas were formed Oil and gas are also biological in origin. Millions of years ago tiny animals lived in the sea. Like today, their ecosystem was dependent on heat and light from the Sun and photosynthesis by plants. When they died they fell into mud and sand at the bottom of the sea but did not rot away. Over millions of years, they were buried deeper by the mud and sand. The temperature and pressure (caused by the weight of the sediments and deep burial) changed the mud and sand into rock and the dead animals into crude oil and natural gas. This sample of crude oil was formed in southern England. Crude oil formed in other parts of the world can be very different in appearance and viscosity.

Oil and gas formation

Fossil fuels summary

7I Energy Resources The nature of energy Energy resources Fossil fuels Contents 7I Energy Resources The nature of energy Energy resources Fossil fuels Summary activities

Glossary energy – The ability to do work. It exists in different forms such as chemical, electrical, heat and light. energy transfer – Changing energy from one form to another. energy resource – A substance that is a source of energy. fuel – A substance that releases energy when it burns. fossil fuel – A fuel that is formed from the remains of dead plants and animals, such as coal, oil and natural gas. non-renewable – An energy resource that cannot be replaced and will eventually run out. renewable – An energy resource that can be replaced and will not run out.

Anagrams

Multiple-choice quiz