What is Electricity?

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What is Electricity?
Electricity is the flow of charge. It is a
secondary energy source, because it is produced
from primary sources like coal, oil, and natural
gas. Primary sources are burned to turn water
into steam, which then turns a generator to
create electricity.
Non-Renewable Energy

• Oil
• Nuclear
• Coal
• Natural gas

Energy sources which cannot be remade as they are
being used they will eventually run out.
Non-Renewable Energy

• Wind
• Solar
• Geothermal
• Water hydroelectric, wave and tidal
• Biomass waste material

Energy sources which naturally replace themselves
or which can be reused. They will not run out.
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Coal fired Power Station
Case study DRAX POWER STATION

• Located near to Selby Coal fields, as coal is
  bulky and expensive to transport.
• The Humber estuary provides deep water for ships
  to carry imported coal
• River Ouse provides water supply
• Located in an area of relatively high demand,
  near to conurbations of Yorkshire and Kingston
  upon Hull
• Most coal is imported, but Drax uses British Coal
  transported by freight line
• M62 provides excellent transport links.

• Facts about Drax
• Largest single electricity generator in the UK,
  second largest in Europe
• In 2005, Drax produced 20.8 million tonnes of
  CO2, largest producer of CO2 in UK
• Produces enough electricity to supply 4 million
  people.
• Between 2007 2012, 100 million is being spent
  on reblading turbines to improve efficiency.
• Hot water from the power station is used to heat
  glass houses where out of season vegetables are
  grown.

Sketch map of area
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Gas fired Power Station
Case study Connahs Quay

• Located in North Wales, just across the English
  border
• Banks of Dee estuary which provides water supply
  for cooling
• High demand for electricity from Liverpool and
  Manchester
• Markets of Liverpool and Chester within 20km
• Gas transported by pipeline from Irish Sea Gas
  Fields to an offshore terminal
• Large flat site

Connahs Quay
The Dash for Gas
In 1999, gas supplied 38 of the UKs electricity
demand. Estimates say that 60 of electricity
will be generated form natural gas in 2010. In
the 1990s, the government agreed to cut C)2
emissions by 10 by 2000, in the Kyoto agreement.
They did this by replacing coal fired power
stations with gas, as gas has a higher calorific
value and is cleaner.
Sketch map of area
4
Nuclear Power Station
Case study Heysham Nuclear Power Plant

• North West England
• Cheap, underdeveloped land
• Large flat area of land in sparsely populated
  area which is unsuitable for agriculture
• Coastal site provides water for cooling
• Rail links for transportation of uranium

Heysham
24 of British energy is supplied by nuclear. The
labour government made a pledge not to build new
nuclear stations and to decommission old ones.
Political and economic pressures have forced the
government to make a U turn, and nuclear is back
on the energy agenda.
How Nuclear Works

1. Radioactive minerals such as uranium are mined
2. Atoms are split (fission) or joined together
   (fusion) in nuclear reactors
3. Reaction created heat
4. Heat boils water, produces steam
5. Steam turns turbines producing electricity
6. Electricity goes into National Grid for
   distribution

Sketch map of area
5
Hydroelectric Power Station
Case study Dinorwic HEP
High rainfall in Snowdonia mountains creates a
reliable water supply
Dinorwic
Sketch map of area
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Hydroelectric Power Station
Case study Dinorwic HEP
How does it work?

1. Reservoir provides water supply
2. Sluice gates control water flow
3. Water flows downhill in pipes
4. Force of water spins turbines, generating
   electricity
5. National grid distributes electricity
6. Water pumped back using off peak surplus
   electricity.

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Wind Farm Power Station
Case study Lambrigg Wind Farm, Cumbria

• Located in Cumbria, North West England
• Located on top of ridge, 260m above sea level
  very exposed site
• Borders Eastern edge of Lake District National
  Park
• It is positioned outside the National Park
  otherwise planning permission would have been
  refused
• East of M6 motorway good access for building
  and maintenance.
• The turbines work with winds between the speeds
  of 5 and 25 km per hour.
• The turbines generate enough electricity to meet
  the average annual needs of around 4,000 homes.
• The electricity produced by these turbines flows
  through underground cables to a substation
  located on the site.
• The wind turbines have a lifespan of 20-25 years
  leaving no trace of their existence and no legacy
  of pollution to pass on to future generations.

Sketch map of area

• Advantages
• Capable of being developed commercially in UK
• Safe, clean, does not contribute to global
  warming or acid rain
• Has only a small effect on local ecosystems
• Winds strongest in winter when electricity demand
  peaks
• After initial construction, electricity is
  relatively cheap
• Can provide a source of income for farmers and
  may attract industry in isolated areas

• Disadvantages
• Expensive to build and maintain
• Wind doe s not blow all the time unreliable
• Spoils scenic countryside areas
• Noisy and can interfere with radio and TV signals
• Inefficient 7000 turbines needed to produce the
  power that 1 nuclear power station can produce

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Fuel Advantages Disadvantages
Coal Reserves are likely to last for over 250 years. Improved efficiency has increased the output per worker, allowed coal mining with fewer accidents and made conversion to electricity more economic Coal can be used not only for making electricity but also for heating and making gas. Most easily accessible deposits have been used up and production costs have risen Increasing competition form other types of energy coal has gone from producing 40 of UK energy in 1970 to less than 30 in 2000. Combustion of coal releases CO2 contributing to global warming, and SO2 contributing to acid rain Coal mining can be dangerous and exposed mining often harms the environment.
Gas High calorific value More efficient to burn, easier to transport and distribute by pipeline and tanker than coal. Cleaner, cheaper and less harmful to the environment than coal. Safer than nuclear. Increasingly the most popular of all non renewable sources during 1990s most new power stations were gas and many coal were converted to gas. Releases CO2 and SO2 contributing to global warming and acid rain Will eventually run out
Nuclear Very small amounts of raw material needed 50 tonnes of uranium per year compared to 540 tonnes of coal per hour Safeguard make accident risk minimal Reserved of uranium will last much longer than cal and gas Waste is limited and is stored underground Nuclear power contributes less to greenhouse effect and acid rain Not clear how safe nuclear power is several serious leaks at Sellafield One serious accident may kill many and ruin land for hundreds of years Irish Sea increasingly contaminated Potential health risks High incidences of leukaemia around Sellafield and DounRay are linked to proximity to nuclear stations Nuclear waste can remain radioactive for 150 years Cost of decommissioning power stations in very high the first was in 1989 at Berkely.
Hydro-Electric Power (HEP) Renewable and often produced in highland areas where population is sparse Relatively cheap and produces only limited pollution Dams built to store water for HEP production can reduce risks of water shortages and floods. Dams are very expensive to build Large areas of farmland and wildlife habitat may be flooded forcing people and animals to move Unattractive pylons cause visual pollution Possibility of dam collapsing Silt which was previously spread out over farm land will be deposited in the lake. When an area is flooded, the decaying vegetation can release methane and CO2, greenhouse gases.
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Action taken to resolve Problems...

• Coal
• Sulphur scrubbers installed to remove sulphur
  from emissions at a cost of 1 million
• Freight lines to minimise environmental impacts
  of transportation
• Temperature of water returning to river is
  monitored and controlled
• Strict controls on open cast mining

• Gas
• New gas stations have improved thermal efficiency
  produce 50 less CO2 than coal fired station
• People friendly education centres on site
• Cooling water is only abstracted and returned
  from River Dee at specific times, around full
  tide, to cause as little environmental damage as
  possible.
• Use of hybrid cooling towers to reduce pollution
  of local areas and reduce impact of
  microclimates they create

• Nuclear
• Build plants in sparsely populated areas away
  from large cities
• Transport uranium in huge steel flasks with high
  safety requirements
• Constant safety checks, especially on water
  returning to sea

• HEP
• Dam built in remote area to reduce human impact
• Main power plant, service tunnels and pipe work
  all located underground to minimise visual impact
  on National Park.
• Surge pond created to minimise risk of plant
  failure or flooding.

• Wind
• Turbines positioned below ridge summit so blades
  cannot be seen from Cumbria
• Away from villages and farms so noise pollution
  does not disturb
• Support of locals encouraged turbines named
  after local school children who won a competition
  at their primary school.