St. Michael’s RC School Renewable Energy. St. Michael’s RC School Does the UK need alternative energy supplies? energy sources (UK 2003)

St. Michael’s RC School

Renewable Energy


Does the UK need alternative energy supplies?

energy sources (UK 2003)

17%

9%

1%

32%

41%coal

nuclear

HEP and otherrenewablesoil

natural gas

1950

2000

2050

2100

2150

2200

NaturalGas

Oil Coal

World -estimatedreserves


Renewable energy sources

These will not run out because they can be regenerated. Examples are wind power, solar power, tidal power and biomass.

Charcoal - a fuel produced from wood (biomass)

Only 1% of the UK’s energy comes from these sources. Can you think of a reason why?


Solar energy

Solar panels

Photovoltaic cells are made of the abundant element silicon.

Photovoltaic cells are silent.

Photovoltaic cells have low maintenance costs.

Why isn’t solar energy popular in the UK?


Wind energy


Wind energy - the disadvantages

Some people also consider the wind farms as visually unattractive and noisy.

What are the advantages of wind energy?

Rotor blades can be damaged in strong and turbulent winds.

It takes 30 wind farms to generate the same amount of electricity as one coal-fired power station. The setting up costs for wind farms are therefore more expensive than for traditional, fossil fuel power stations.

In theory, the UK could generate all its electricity from wind farms covering approximately 1% of the land. But the problems are wind turbine design and cost.


Advantages of wind energy

cooling towers

Wind power can be developed on a small scale.

Wind farms create jobs in rural areas.

Wind farms can be constructed in a few months (thermal power stations take

between 6–10 years to complete).

Wind fuel is free.


Where should the new wind turbines be located?

12

3

It has been decided to locate new wind turbines in this area. Choose from the three sites indicated and justify your answer.

wind direction

town


NIMBY


Hydroelectric power

Hydroelectric electricity is the most popular type of renewable energy. In some countries, such as Brazil, it represents most of the energy produced. Hydroelectric energy is produced from fast flowing water, such as at a waterfall or by an artificial dam.

Dam at Donzere, France


Hydroelectric power


Tucurui Dam, Brazil – cost $5 billion

Tucurui Dam was built between 1976 and 1984, on the Lower Tocantins River in the state of Para, approximately 300km south of Belem. The reservoir created upstream of the dam is over 2000km². Tucurui will produce more than 4000 MW of electricity.


TucuruiDam

Amazonian Indian village

HEP plant

Road

flooded an area 5 times the size

of the Isle of Wight

Before Tucurui Dam After Tucurui Dam

Describe the dam’s impact on the landscape

River Tocantins


Hydroelectric power – impact of building dams

tourists may be attracted to the area

silt is trapped behind the dam and is not transported downstream where it is needed for farmers and fishermen

may decrease flooding downstream

the water behind the dam is stagnant and algae builds up

building dams floods large areas

dams control the flow of water

These are some of the advantages and disadvantages of building a dam.


Energy is generated by the tidal rise and fall. The tides come in and pass through holes in a dam wall. The water is then trapped in a river estuary. Then the tide ebbs and passes back through the barrage, driving the turbines and producing electricity. Tidal energy is generated at La Rance in western France. A suitable site in Britain would be the River Severn. This barrage would cost between £3 billion and £9 billion and be able to generate between 5% and 10% of Britain’s total electricity demand.

Tidal energy


Wave energy

The island of Islay, off the west coast of Scotland has had a Limpet (land-installed marine-powered energy transformer) constructed, which should provide a reliable electricity supply for the 3,400 residents. A 25-metre notch has been cut into Islay’s south west facing cliffs at Portnahaven into which a wave chamber has been inserted. The waves rise and fall in this wave chamber compressing the air and so driving the turbines which power the generators.

Why has the wave chamber been placed on the south west of the island?

incoming waveslow tide

high tide

turbo generator


Geothermal energy

Hot water Cold Water

geothermal plant

fractured rock

Geothermal energy is obtained from heated rocks and molten magma under the Earth’s surface.


Geothermal energy is generated extensively in tectonic areas, such as Iceland and New Zealand. Why is this the case?

Plate Map


often located in exposed areas such as mountainous regions

Wave

Solar

Geothermal

Wind

HEP

Tidal

Match the statement with the energy source

water stored in dams is released through turbines to generate electricity

located on the coast with a chamber facing the prevailing wind

mirrors concentrate the sun’s rays onto water-filled black pipes

powered by a man-made barrage, usually found across an estuary

heat produced by rocks under the Earth’s surface

heat produced by rocks under the Earth’s surface

water stored in dams is released through turbines to generate electricity

located on the coast with a chamber facing the prevailing wind

mirrors concentrate the sun’s rays onto water-filled black pipes

powered by a man-made barrage, usually found across an estuary

often located in exposed areas such as mountainous regions

Documents

St. Michael’s RC School Renewable Energy. St. Michael’s RC School Does the UK need alternative energy supplies? energy sources (UK 2003)