Energy - Chapter 5 CT-1

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Fossil fuels:

Energy from the fossil fuels oil. gas. and coal is used

to generate 90 per cent of electricity in the UK.

There are limited supplies of fossil fuels. and once

they are gone they cannot be replaced for many

thousands of years. For this reason. fossil fuels are

also called non-renewables. Map D shows how long

different fuel reserves will last if we continue to use

fuel at the rate we use it today.

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Energy and the environment:

All forms of energy have some impact on the

environment. What are the impacts of burning fossil

fuels? The Sun's energy passes through the

atmosphere and warms the surface of the Earth.

Heat is both reflected and radiated from the Earth.

This heat is trapped by carbon dioxide (CO2) and

other greenhouse gases in the atmosphere. This is

known as the greenhouse effect. A certain amount

of such warming is essential. Without it, scientists

believe, the atmosphere would be on average 33°C

colder than it is.

global warming:

The amount of greenhouse gases is increasing.

Burning fossil fuels and wood releases more and more

CO2 into the atmosphere. Other gas emissions from

industry, vehicles, and farming add to the amount of

'greenhouse gases' in the atmosphere. Some

scientists believe this will lead to a rise in average

global temperature over the next century. Ice caps

could begin to melt, and areas on the edges of deserts

could become hotter and drier.

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Increasing greenhouse gases will affect the world's'

climate. Temperatures will rise. and storms may

become more common. In hot. dry regions of the

world droughts and food shortages might happen

more often. Map E shows one forecast of changes in

temperature around the world. Table D shows that

sea levels will rise. but it is difficult to predict by how

much.

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The threat of coastal flooding:

Low-lying coastal areas such as East Anglia in the UK, the Netherlands, and

Bangladesh would be badly affected by even a small rise in sea level. Coral

islands such as the Seychelles in the Indian Ocean could be completely

submerged. A rise of only 45cm would submerge 70 per cent of the Seychelles.

Pacific islanders are also extremely worried about possible flooding. The tiny

Island of Tuvalu is one island under threat. It has an area of 16km2 and a

population of 9000. Average incomes are below US $700 per year.

Why is tiny Tuvalu getting

so annoyed with Britain?

Tuvalu as a country may cease to exist next century jf the Earth

gets warmer. Its highest point is one metre above sea level. and

storms in the Pacific Ocean are already washing over the

country. The European Union is building a sea barrier of four-

legged concrete blocks to protect the capital, Foangafale. And

the Dutch said that they would look into the possibility of a sea

wall. Only Britain seems to want to stand apart.

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Coastal defences

in the Netherlands:

The Netherlands is a rich European

country with an average income of

US $20 590. Its best farm land, the

polders, was reclaimed from the sea

and these fields are already below sea

level, as map F shows. Of the 15.4

million people who live in the

Netherlands, 9 million live in the

polders.

The Dutch people have built an

expensive system of sea defences.

Granite boulders imported from

Germany are dumped offshore to break

the force of the waves. Large concrete

blocks are also used. A dyke

{embankment} prevents the sea from

flooding the polders. Rock groynes help

to trap beach material in front of the

dyke. Barrages built across the mouths

of rivers help prevent flooding of the

estuaries at high tide.

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Nuclear power:

At present the UK gets most of its energy from the

three fossil fuels - coal, oil, and gas. The best

developed alternative is nuclear power. However,

several countries are looking at reducing their

nuclear programmes. The USA, for example, has

stopped building nuclear power stations. In the UK

the government is reviewing the development of

nuclear power. Why are countries having second

thoughts about nuclear power? Do the problems of

nuclear power really outweigh the benefits?

Problems of nuclear power in France:

France relies heavily on nuclear power as its major

form of electricity generation, and this has caused

problems. During 1989-1990 design faults were

found in several nuclear reactors. At the same time a

major drought affected the supply of water to some

nuclear plants. The drought also affected the

country's hydro-electric schemes. Together these

factors greatly reduced the power supply. As a result

France had to import electricity.

The nuclear programme has also caused problems

for the environment. It produces large amounts of

radioactive waste but the industry still does not have

an accepted way of dealing with the waste safely.

Power generation in France:

France has very rapidly created the most developed

nuclear industry in the world. Nuclear power

provides 75 per cent of France's electricity from 56

nuclear reactors. France has very small reserves of oil,

coal, and gas, so the development of nuclear power

has greatly reduced its dependence on fuel imports

from other countries. Its carbon dioxide emissions are

among the lowest in Europe. The cost of developing

the nuclear power industry has been very high;

Electricite de France (EdFI. the state electricity

company, had a debt of £25.4 billion by 1990.

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International problems:

In April 1986 an accident at Chernobyl in Ukraine

had a massive impact on people and the

environment. An explosion in one reactor blew a

large amount of radioactive material 5km into the

atmosphere. This then spread across Europe, from

Scandinavia to Greece. High levels of radioactivity were found as far away as the UK. Soldiers who tried

to stop the leak died. Local people were evacuated,

and some have become sick. Soil, plants, and

animals were contaminated as far away as northern

Scandinavia and north Wales. European countries are

now worried about the safety of the remaining

reactors in Russia and eastern Europe.

Factfile: Chernobyl -

- 31 people died immediately, others are now dying

from illnesses caused by the high levels of radiation.

- 10 000km2 land was contaminated

- 220 villages were abandoned

- In 600 villages soldiers tried to decontaminate

buildings

- 116000 people were evacuated and

500 000 made homeless

We decided in the late 1970s not to

develop a nuclear programme. But we

have become increasingly concerned

about the reactors close to our border

In the Czech Republic and Slovakia. So

much so that we have offered the Czech

Republic free electricity if it will shut.

down some of its closest, older

reactors. We call on our neighbours to

help widen the 'nuclear free zone' within

central Europe

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Renewable energy:

Renewable energy is generated from sources which

are constantly being replaced, such as the wind, sun,

and water. The energy from renewable sources used

during 1993 in the UK was just under 1 per cent of

I

all the energy used. Many experts think we could

produce far more renewable energy. Some people

believe that renewables could produce 20 per cent

of our electricity supply by 2005.

There has been a great deal of interest in wind

power in the UK. Wind generators create no waste

and no greenhouse gases; besides, the wind is free

and cannot be used up. But even renewable forms of

energy cause problems. Each wind generator

produces a relatively small amount of electricity, and

so between 25 000 and 35 000 wind generators would

be needed to produce 20 per cent of the UK's

electricity. People think that this number of wind

turbines would look ugly, make too much noise, and

interfere with TV pictures. Yet this number of wind

generators is smaller than the 50 000 electricity

pylons already sited around the country. We accept

that if we want electricity at the flick of a switch we

must have pylons.

Factfile: Renewable energy:

• Wind - wind turbines can be used to generate

electricity or pump water.

• Sun - solar panels absorb energy from the sun and

either heat water or generate electricity.

• Water - water flows through a turbine, generating

electricity. This is known as hydro-electric power

(HEP). A small-scale example is shown in photo A

and diagram B.

• Sea power - energy could be generated from the

rising and falling of the waves. Barrages (or dams)

built across an estuary could generate electricity

from the movement of the tides.

• Geothermal energy - water is pumped down deep

holes in the ground to extract heat from hot rocks in

the Earth's crust (see page 23).

• Energy from waste - the waste that we produce

can be burnt to produce heat or electricity. Methane

(biogasl from rotting waste or sewage can be burnt

to produce heat and generate electricity.

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Energy from waste:

In 1994. of all the household waste in the UK. 87

percent was tipped on landfill sites. These sites can cause

serious environmental problems. as diagram D shows.

Instead of throwing our rubbish away. we could use it to

generate electricity.

Domestic. industrial, or agricultural waste can be burnt to

produce energy in the form of hot water or electricity.

•Methane (biogas) is produced when material decomposes

(rots) without oxygen. The gas can be produced from landfill

sites. sewage works. and farm slurry. Methane can then be

burnt to produce heat and generate electricity.

Biogas has been used a lot in developing countries. The

production of biogas involves the whole community in a far

greater way than energy production in the UK.

The people of Gujarat in India used to cook using firewood.

But deforestation was causing serious problems. and women

were walking further and further to collect wood. Biogas plants

have been set up to provide energy in some villages. One such

plant is in Methan. Gujarat. Sources A to E on the next page

explain how the biogas scheme works and how it is run by

local people.

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The biogas co-operative scheme:

The biogas plant in Methan, Gujarat, is run by the

community. Manure is collected from all the members

of the project who have cattle. This manure ferments

in the chamber to produce methane gas. This gas is

then used for cooking and the solid waste from the

biogas chamber is used as fertilizer for the crops. The

gas and fertilizer are given to the members in

proportion to the amount of manure they provided in

the first place.

It took a long time to

convince people. It was

difficult to persuade them

to contribute gobar (dung)

to the gas plant. They

would not believe that

slurry from the gas plant is

a richer fertilizer, or that

they should fit in with the

community cooking times.

Also. people want to keep

takmg the wood that is free

rather than pay the small

sum to become co-

operative members.

We have gained so much,

especially us women. No

more smoky homes, no

coughs or burning eyes,

for us or for our children

who are with us all the

time in the kitchen. And

how much time we save,

not looking for firewood

every day!

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Saving energy and recycling:

As well as finding alternative sources of energy, we

should also try to find ways of using energy more

efficiently. Energy can be saved by avoiding wasteful

packaging materials, or by reusing them. Materials

can also be recycled. It takes 25 times less electricity

to recycle an aluminium drinks can than to make a

new one.

Energy can also be conserved around the house.

Using long-life, low-energy light bulbs is one

example. Image F shows how much energy is lost

from an average family house. Diagram G shows how

this can be improved. Houses are now being

designed and built to be as energy efficient as

possible. Photo H shows one such house. The front

has large windows (top picture); while the back has

small windows (bottom picture).

Review:

Energy is an essential resource but it is not

shared equally. As the fossil fuels

are being used up, we must look for alternative

sources of energy. In making decisions about

energy production we need to consider:

what impact it might have on the environment

how we can use energy more efficiently.

Fossil Fuels:

• Energy from fossil fuels (oil, gas, and coal) generates 90% of electricity in the UK.

• Fossil fuels are limited and non-renewable; once depleted, they cannot be replaced for thousands of years.

Energy and the Environment:

• All forms of energy impact the environment.

• Burning fossil fuels releases greenhouse gases, such as carbon dioxide (CO2).

• The greenhouse effect traps heat, keeping the Earth's average temperature warmer, preventing it from being 33°C colder than it is without it.

Global Warming:

• The amount of greenhouse gases is increasing due to burning fossil fuels, wood, and other emissions from industries, vehicles, and farming.

• Scientists predict a rise in average global temperatures that could lead to melting ice caps and hotter, drier regions.

Climate Change Effects:

• Increased greenhouse gases will lead to rising temperatures, more storms, droughts, and food shortages in hot, dry regions.

• Sea levels are predicted to rise, but the extent is difficult to predict.

Threat of Coastal Flooding:

• Low-lying coastal areas (e.g., East Anglia in the UK, the Netherlands, Bangladesh) are vulnerable to sea-level rise.

• Coral islands like the Seychelles could be completely submerged with a rise of only 45 cm, affecting 70% of the islands.

• Pacific island nations, such as Tuvalu, face existential threats with rising sea levels; Tuvalu's highest point is only 1 meter above sea level.

UK's Role in Tuvalu's Future:

• Tuvalu's future is uncertain as it may cease to exist next century due to rising sea levels and storm surges.

• The EU is building a sea barrier for Tuvalu’s capital, but Britain is perceived as unsupportive in comparison.

Coastal Defences in the Netherlands:

• The Netherlands, with an average income of $20,590, relies heavily on coastal defenses due to its below-sea-level polders.

• A complex system of sea defenses includes granite boulders, large concrete blocks, dykes, rock groynes, and barrages to prevent flooding.

Nuclear Power:

• The UK primarily uses fossil fuels for energy, but nuclear power is a well-developed alternative despite some countries reducing nuclear programs.

• The USA has ceased building nuclear power stations, and the UK government is reviewing its nuclear development.

Issues with Nuclear Power in France:

• France relies on nuclear power for 75% of its electricity from 56 reactors but has faced design faults and drought impacting water supplies.

• The nuclear industry generates large radioactive waste, and there are no accepted long-term waste disposal methods.

Chernobyl Accident:

• The 1986 Chernobyl disaster released radioactive material across Europe, with immediate and long-term health consequences.

• 31 deaths were immediate, with thousands affected by radiation exposure.

• The accident contaminated 10,000 km² and caused the evacuation and abandonment of 220 villages.

Renewable Energy:

• Renewable energy sources include wind, solar, hydro, sea power, geothermal energy, and energy from waste.

• As of 1993, renewable sources accounted for just under 1% of energy used in the UK.

• Experts believe renewables could supply 20% of electricity by 2005.

• Wind power is becoming popular due to no waste emissions, although many turbines would be needed to meet the demand.

• Each wind turbine has aesthetic and practical challenges but is preferred over existing pylons.

Energy from Waste:

• In 1994, 87% of household waste in the UK was sent to landfill, causing environmental issues.

• Waste can be incinerated to produce energy; methane gas from decomposition can be utilized for heating and electricity.

• Biogas initiatives have emerged in developing countries, providing community-level energy sources.

Biogas Co-operative Scheme:

• In Methan, Gujarat, a community-run biogas plant uses cattle manure to produce methane for cooking and fertilizer.

• Community involvement was initially challenging due to distrust and habits toward traditional fuel sources.

Saving Energy and Recycling:

• There's potential for energy savings by reducing wasteful packaging and increasing recycling efforts.

• Recycling aluminum saves 25 times less electricity than producing new materials.

• Energy conservation practices at home include using long-life, low-energy light bulbs and designing energy-efficient homes.

Review:

• Energy is an essential and unequally distributed resource, and as fossil fuels deplete, alternative energy sources should be considered alongside environmental impacts and efficient usage.