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What is Nuclear Power

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					  Protons for Breakfast


         Week 6

Do we need nuclear power?
In the event of an alarm sounding…
Nuclear Power
The UK Energy Scene
Tonight’s Talk
Electricity generation in the UK




 • How is electricity generated?
 • How much electricity does Britain need and where does it come from?
 • Nuclear Power Stations are due for closure
    – How to replace the lost generating capacity?
    – Reduce demand, Wind Power, Tidal Barrage, Solar Power?
 • Nuclear Power?
    – Radioactivity & Nuclear Fission
    – Pros and Cons


               Does Britian need nuclear power?
Helpers           Jonathan Pearce     Experts
                  Laurie Winkless     Martin Milton
Andrew Hanson     Lindsay Chapman
Arzu Arinc                            Paul Quincy
                  Lloyd England
Averil Horton     Mateusz Szymanski   Nigel Fox
Bufa Zhang        Matthew Tedaldi     Andrew Gregory
Clive Scoggins    Neelaksh Sadhoo     Andrew Beardmore
Daniel Gittings   Paul Carroll
Davide Di Maio                        Bob Clarke
                  Peter Quested
Deborah Lea                           Kevin Lees
                  Peter Woolliams
Emma Woolliams    Rainer Winkler      Alan DuSautoy
Gianluca Memoli   Richard Gilham      Alan Turnbull
Jacquie Elkin     Robert Goddard      Nigel Jennett
James Miall       Robin Underwood
Jeff Flowers                          John Makepeace
                  Ruth Montgomery
Jenny Wilkinson   Sharmila Hanson     Simon Jerome
Jian Wang         Stephanie Bell
Joanna Lee        Thomas Korrison
John Makepeace
John Mountford
Electricity




                Eeeee - lec- tric-ity




              Where does it come from?
Tonight’s Talk




             How is electricity generated?
How is electricity generated? (1)
   Type of      Electricity        What makes coil         Energy
   station      made by…                turn?              Source         Ultimate Source

               Coil turning in a   Turbine driven by       Chemical
    Coal        magnetic field        hot steam          C + O2  CO2
                                                                              Solar


                                                          Chemical
               Coil turning in a   Turbines driven by
                                                         CH4 + 2O2           Solar
    Gas         magnetic field     hot gas and steam
                                                          CO2 + 2H20



               Coil turning in a   Turbine driven by    Nuclear Fission
  Nuclear       magnetic field        hot steam           U + n ???
                                                                              Stellar


               Coil turning in a   Turbine driven by    Nuclear Fusion
Wind/Wave       magnetic field        air or water         4H  He
                                                                              Solar


      % of solar energy is renewable & sustainable
 0.01 Only ‘solar’ power would meet all energy demands
Mamod




         Coil turning in a   Pistons driven by     Chemical
 Mamod    magnetic field          steam          C + O2  CO2
                                                                ?
While the station powers up…




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            Ticking the boxes is important, but
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How much electricity do we need?
Electricity Generation in UK                                                           gigawatt (GW)
                                                                                  1 gigawatt (GW)
Daily variations in 2001/2002                                                   billion watts =10=109 W
                                                                                   billion watts 9 W
                                                                                     = 100 W light bulbs
                                                                            =10 Million1000000000 W
                                                                                 =10 Million Light bulbs
                                                                       Roughly speaking 1 large power station

                                   60                                                                             60
                                                                                                                         Maximum Winter Demand
Actual National Grid Demand (GW)




                                                                               Actual National Grid Demand (GW)
                                   50                                                                             50
                                           Typical Summer Demand
                                   40                                                                             40


                                   30                                                                             30

                                                                                                                           Typical Winter Demand
                                   20                                                                             20
                                           Minimum Summer Demand
                                   10                                                                             10

                                        Sleep           Work                                                           Sleep           Work
                                   0                                                                              0
                                   0.00     6.00      12.00    18.00   24.00                                      0.00     6.00      12.00    18.00   24.00
                                                   Time of day                                                                    Time of day
Electricity Demand 2001-2009
                               Mmmm. Looks near to
                               60 GW peak demand!
Energy Consumption Right Now!



How do we meet this demand?
Electricity Generation in UK

                                                                                                                                       Typical Winter Demand
               Figure 2.5(b) - Typical Winter Demand (Thursday 6th December 2001)                                                      Thursday 6th December 2001
 Power
              60                                                                                                                                                                                                Other
  (GW)
                                     Imports
     50       50




     40       40




                                                                                                           Large Coal
         MW




     30       30




     20       20



                                                                                   Gas (Combined Cycle)
     10       10



                                                                                                                   Nuclear
         0    0
                   00:00

                           01:00

                                   02:00

                                           03:00

                                                      04:00

                                                              05:00

                                                                        06:00

                                                                                07:00

                                                                                           08:00

                                                                                                   09:00

                                                                                                           10:00

                                                                                                                    11:00

                                                                                                                             12:00

                                                                                                                                     13:00

                                                                                                                                               14:00

                                                                                                                                                       15:00

                                                                                                                                                               16:00

                                                                                                                                                                       17:00

                                                                                                                                                                                18:00

                                                                                                                                                                                        19:00

                                                                                                                                                                                                20:00

                                                                                                                                                                                                        21:00

                                                                                                                                                                                                                22:00

                                                                                                                                                                                                                        23:00
                   0:00                                                6:00                                                  12:00                                             18:00                                        24:00
                                                                                                                            Time
                                                                                                           Time of Day
                                                   Nuclear            CCGTs             Outside Sources             Large Coal               Other Coal          Oil      Pumped Storage                Other
Electricity Generation in UK
Data from 2004




                               Wind/Biomass/Landfill Gas
                                          3.5%             Imports
                               Hydroelectric                2.5%
                                   1%

                                                              Coal
                               Nuclear                        33%
                                19%


                                                             Oil
                                                             1%
                                         Gas
                                         40%
Current UK Nuclear Capacity
                                                                                • Decline could be faster
History and Future
                                                                                                     • Energy Gap?

                                    14


                                    12
 Installed Nuclear Capacity (GWe)




                                    10
                                                                                                                    Total
                                                                                                                    Magnox
                                     8      History                                           Future                AGR
                                                                                                                    SGHWR
                                     6
                                                                                                                    PFR
                                                                                                                    PWR
                                     4

                                     2

                                     0
                                     1950    1960   1970   1980   1990   2000   2010   2020   2030    2040   2050
                                                                         Year
Electricity Generation in UK
2020




• No shortage of coal and              Wind/Biomass/Landfill Gas
  gas                                             3.5%                  Imports
                                       Hydroelectric                     2.5%
    – See BP Energy Review                 1%
    – Cost?
                                          ??????????
    – Security of supply?                                                  Coal
                                            Nuclear
                                          ??????????                       33%
                                          ??????????
• Renewables will increase
    – but by how much?
                                                                          Oil
                                                                          1%
• Nuclear will decline                            Gas
                                                  40%
http://www.bp.com/productlanding.do?categoryId=6929&contentId=7044622
One Solution…
The Nuclear Solution
Alternatives?
                               Renewable 60

                                             50
Is there an alternative?
• Increase Renewables                        40
                                    Gas
• Reduce Gas and Coal generation     &
                                    Coal     30
• Avoid Nuclear Power

                                             20
  Can we reduce demand?
                                             10
                                   Nuclear
What to do?          • My family’s electricity usage for the last four years
Reduce Electricity   • Can we force people and businesses to use less?
                        – Price
Demand
                        – Rationing



                         Annualised Electricity Consumption

      10000
                 2005           2006            2007            2008
       9000

       8000                                                     2000 kWh
       7000
                                                         £260 a year
                                                              20% reduction
       6000
kWh




       5000

       4000

       3000

       2000

       1000
Electricity Usage in UK 2004         Universal use of CF light bulbs will
                                            eliminate the need for
                                          1 large power station


                                                     Lighting
• Several easy wins                Commercial
                                      18%
                                                             Domestic
                          Losses                               29%
                            8%
                           Fuel
                        Industries
                            8%
                            Public
                        Adminsitration                      Industry
                              5%                              29%
                         Transport 2% Agriculture 1%
Alternatives?
                                             60
                Most people would think
                this is wildly optimistic!
                                             50

           So reducing demand could help.    40

                  What can wind provide?     30

                                             20

                                             10
Wind Power (1)
UK Wind in 2007



• UK has some of the best
  sites in Europe
• Currently
  – 279 Projects
  – 3141Turbines
  – 5.179 GW
18 GW in a few years time
        Divide numbers
          by 3 to get
        average power
Wind Power                                       •Wind has problems of
Could we get 10% (5.3 GW) of                          –availability
electricity from wind?
                                                      –variability

                 • Build 5000 of the largest wind turbines

             13 GW
                    • On average generates only 5.3 GW
                    • Sometimes more: Sometimes less!
                    • Can’t control when!

                                                 • Retain 3 GW of coal fired
                                                   capacity as ‘backup’
                            5.3 GW
                                                             3 GW
Alternatives?
                                                  60
                Very ambitious, but
                   achievable…
                                                  50
                                                        WIND


                                                  40
           So wind can provide a lot of power,
         but we can’t control when it is generated
                                                   30
           Could we store some of the power?

                                                  20

                                                  10
Wind Power
The Grid

• Electricity needs to be generated at
  exactly the time it is needed.
• Storage is possible, but difficult:
• Variability limits likely maximum
  wind contribution to about…
   – 10%? Yes
   – 20%? Arguably
   – 30%? Unlikely




Photo Credit Spencer Jarvis
Electricity Generation in UK                       0 to 1.3 GW
Pumped Storage                                    in 12 seconds

                              1.5
                                             Energy Use
                              1.0
        Pumped Storage (GW)



                              0.5

                              0.0

                              -0.5

                              -1.0
                                             Energy Storage
                              -1.5
                                     0   6       12           18   24
                                             Time of Day
Other Alternatives?
                                                60

                                                50    WIND
                                                      WIND
                                                        &
                                                      STOR
              So reducing demand can help.      40

       And wind and stored energy could help too 30

               What about solar electricity?
                                                20

                                                10
Solar Photo Voltaic
Step 1



 • Put this on your roof
 • 9 m2
 • Twickenham
Solar Photo Voltaic
Step 2



 • Put these in your
   house
Solar Photo Voltaic                                    Daily generation rate
                                10.00
Hey presto!
                                 8.00




                      kWh/day
                                 6.00

                                 4.00

                                 2.00

                                 0.00




                                        10

                                             14

                                                  18

                                                       22

                                                            26

                                                                 30

                                                                      34

                                                                           38

                                                                                42

                                                                                     46

                                                                                          50

                                                                                               54

                                                                                                    58

                                                                                                         62
                                                                      w eek #



• Average: 3.5 kWh/day (1277.5 kWh/year)

• Saving: 3.5 x 13 pence per kWh = 46 p/day (£166 / year)

• Cost in: 2005: £9000

• Return on investment: 1.8 %
Other Alternatives?
                                                   60
                Mainly in Summer…
                                                   50   WIND
                                                        WIND
                                                          &
                                                        STOR
                                                   40
             So reducing demand can help.               SUN


                                                   30
      And wind and stored energy could help too.

                                                   20
               Even solar energy can help

                                                   10
Severn Tidal Barrage



  Could generate
     10% of UK
      demand

       5 GW

        £15B
Nuclear Fusion




                 Nuclear Fusion
Nuclear Fusion
What is it?




                   deuterium
  100,000,000 ºC
    1,000,000
       10,000       nucleus
                           neutron

                               proton
Fusion

                         JET
                http://www.jet.efda.org/

                          ITER
                  http://www.iter.org/

           Probability of Success by 2025…
                    ????25%????

    Probability of Engineering Feasibility by 2100…
                     ???? 5%????
Summary
                          Mmm…Every one of      60
                          these figures looks
                             optimistic…
                                                50   WIND
                                                     WIND
                                                       &
                                                     STOR
       Action                    Effect (GW)    40
                                                     SUN
   Reducing demand                     10
 wind and stored energy
                                                30   TIDE

                                       10
               or lagoons
 tidal barrage !?Barrage Cancelled?!
                                   10           20
      Solar energy                      3
                                                10
And there are many other                ?
     possibilities…
Nuclear Power
The UK Context
Carbon Crunch
                                        60

                                        50   WIND
                                             WIND
     Method of     Kilograms of CO2            &
                                             STOR
     generation   emitted for every 1
                                        40
                    kWhe supplied:           SUN

        Coal              1
                                        30   TIDE


     Gas (CCGT)          0.5
        Wind             0.01          20

        Tide             0.01
                                        10
       Nuclear           0.01
Summary
                                           60

                                           50    WIND
                                                 WIND
                                                   &
  • 11 GW of CO2-free generating                 STOR
    capacity will be retiring in the       40
    next 17 years                                SUN


                                           30    TIDE

  • Even replacing it will not
    reduce CO2 emissions
                                           20

     So let’s find out about nuclear power! 10
 To understand nuclear power
         and how it works
we first need to understand about
        Radioactivity
Some radioactive things (10)




      Let’s look at some radioactive things…
                       Detectors
                    Cloud Chamber
                Supermarket Radioactivity
Remember this…


                     Electricity
‘Nuclear’ refers
  to the nucleus
     of atoms




                                   Heat
   Electromagnetic        Atoms
         waves
How are atoms made?




                      Electrical Repulsion


                                        proton



                                     Interact by the short range
                                    ‘strong’ force – not electrical
How are atoms made?
What is Radioactivity(2)…




• Normally nuclei act as heavy
  point-like centres for atoms
                                         Nucleus
• More than 99.9% of the mass of
  every atom is made of nuclear matter

• More than 99.9% of the mass of your
  breakfast is made of nuclear matter
What is Radioactivity(3)…




     The number of protons (+) in the
     nucleus determines the number
     of electrons(-) required to make
     the atom neutral

     Determines the chemical and
     physical properties of the atom

    But the number of neutrons in a nucleus can vary
What is Radioactivity(4)
                                            Same number of protons
Example 39K, 40K and 41K
                                          Different numbers of neutrons


    • Potassium is 2.4% of the Earth’s crust
    • Natural potassium (symbol K) has three isotopes
           39K               40K                   41K
         19 protons        19 protons            19 protons
         20 neutrons       21 neutrons           22 neutrons
         20 + 19 = 39      21 + 19 = 40          22 + 19 = 41

           93.3%             0.01%                  6.7%
                           Radioactive
What is Radioactivity(6)…




Three types of radioactivity
• Named with the Greek a, b, c
   a alpha, b beta, g gamma
• Nuclei with a ‘balanced’ number of protons and neutrons are stable
                 Isotopes with             Isotopes with
               too many protons         too many neutrons

                  Alpha decay                Beta decay

             Emission of fast moving   Emission of fast moving
                helium nucleus                electron

              And gamma radiation       And gamma radiation
What is Radioactivity(8)
Alpha (a) Decay


         Nucleus with too
          many protons
                                                  Alpha
  gamma ray                                       particle




                            Charge oscillations
                                in nucleus
What is Radioactivity(8)
Beta (b) Decay


         Nucleus with too
          many neutrons
                                                   Beta
  gamma ray                                       particle




                            Charge oscillations
                                in nucleus
Radioactivity




                What are the health risks
                 of ionising radiation?
Radioactive health risks
Introduction



 • Radioactive emissions a alpha, b beta, g gamma
 • If they pass living cells, they interact electrically and cause
   damage.
    – Cells are killed
    – Can cause mutations and cancer
    – Very bad for you
 • Fortunately we have evolved in a radioactive world
Radioactive health risks
Measurement units



 Many ways of measuring radioactive dose
 • Optimal measure for effect on human health is the

                           Sievert
Radioactive health risks
Annual average UK dose


                                    Source         Dose (mSv)
  • Average annual dose to the UK
                                    Natural
    population from all sources
                                    Cosmic            0.26
  • Average 0.0026 Sieverts         Gamma rays        0.35
  • Average 2.6 milliSieverts       Internal          0.3

  • About 7 microSieverts /day      Radon             1.3

                                    Artificial
                                    Medical           0.37
                                    Occupational     0.007
                                    Fallout          0.005
                                    Products         0.0004
                                    Discharges       0.0002

                                    Total             2.6
Radioactive health risks
Sources                                                                From the sky
                                                                       About 100,000 cosmic ray
                                                                       neutrons and 400,000
                                                                       secondary cosmic rays
                                                                       penetrate the average
                                                                       individual every hour

         From food
         About 15 million
 potassium 40 atoms and
    7000 natural uranium
 atoms disintegrate inside                                              From the air
             us each hour
                                                                        About 30,000 atoms
                                                                        disintegrate each hour in
                                                                        our lungs and give of
                                                                        alpha, beta, and gamma
                                                                        radiation




                             From soil and building materials
                             Over 200 million gamma rays pass through the
                             average individual each hour
What is Nuclear Power?




                         Nuclear Power

                    How does it work?
Nuclear Fission (1)
‘Fission means splitting’



  • Some heavy nuclei can
    be induced to fission i.e.
    split in two by the addition
    of a single neutron
  • Nuclear fragments move
    very fast. As they interact
    with nearby atoms they
    cause tremendous
    heating                        One more ‘wafer thin’ neutron, Sir?
Nuclear Fission (2)
Uranium



   • Uranium has two common isotopes 238U and 235U
      – Uranium has 92 protons
      – The 238 or 235 is the total number of protons and neutrons

                      238U                       235U


    neutrons    238 – 92 = 146            235 – 92 = 143
     natural
    uranium.          99.3%                     0.7%

     Fissile?          No                        Yes
Nuclear Fission (3)
Uranium Fission



   •   235U   + n >>> 236U + n

   • After a short while

   •   236U   >>> fragments + 3 n
Nuclear Fission (4)
Sustained Chain reaction
•   235U   + n >>> 236U >>> Fragments + 3n
Nuclear Fission (5)
Uncontrolled Chain reaction
•   235U   + n >>> 236U >>> Fragments + 3n
Nuclear Power Stations
What is Nuclear Power?




                   Nuclear Positives
Nuclear Power
The UK Context
Nuclear Fission (6)




 • 1 kg natural uranium has a volume of 50 cm3
    – Produces 40 thousand kWh
    – Equivalent to 16 tons of coal

 • Nuclear energy is cleaner than coal
    – Lower radioactive emissions
    – Much less radioactive waste

 • Conventional Power Stations
    – Cheaper than nuclear because they don’t pay to clean up their
      waste (CO2)

 • Reliability
    – One fifth of UK electricity supply for last 30 years
What is Nuclear Power?




                  Nuclear Negatives
Nuclear Power
The UK Context
Catastrophic Explosion
Chernobyl



   • 26 April 1986
   • 31 dead Immediately
   • Ultimate death toll
      – 100?
      – 15,000?
Chernobyl
Effect on UK
                                      Fall out from
                                      atmospheric
                                    atomic weapons
 Total radiation                         testing
 dose was 20
 times less than
 the dose from    Annual
 the atmospheric dose
 bomb tests from (micro
 1945 to 1963.   Sieverts)                     Chernobyl




                             1951                     1988
                                     Year
Nuclear Power
The UK Context
Nuclear Fission (4)
Origin of Nuclear Waste
•   235U   + n >>> 236U >>> Fragments + 3n




                                             These fragments
                                               are intensely
                                                radioactive

            Neutrons make other materials radioactive too
Radioactive waste (4)




           No permanent resting place has been
               found for the high level waste

                         Year       Year
      Type of Waste      2000       2030

          Low           424,000   1,411 ,000     Amounts in
                                                 cubic metres


      Intermediate      100,000   260 ,000

          High           1,200      3,000
Waste (4)
Carbon versus Nuclear




                           Radioactive       Carbon Waste
                             Waste               (CO2)

                            Large, but
          Cost                                Incalculable
                            calculable

    Worldwide Physical   <1 million tonnes >30 billion tonnes
          Mass           cumulative total       per year


       Manageable            Probably         Probably not
Nuclear Fission (6)
Chain reaction



  • Nuclear phenomena have
    always been associated
    with great hopes and great
    fears.

  • Chicago
  • 3:25 P.M. December 2,
    1942
  • Nuclear Age began
  • Gain = 1.0006
Nuclear Fission (6)
Hopes



Arthur Compton
• One of the things that I shall not forget is the expressions
  on the faces of some of the men. There was Fermi's face—
  one saw in him no sign of elation. The experiment had
  worked just as he had expected and that was that. But I
  remember best of all the face of Crawford Greenewalt. His
  eyes were shining. He had seen a miracle, and a miracle it
  was indeed. The dawn of a new age. As we walked back
  across the campus, he talked of his vision: endless
  supplies of power to turn the wheels of industry, new
  research techniques that would enrich the life of man, vast
  new possibilities yet hidden.
Nuclear Fission (6)
Fears

Leo Szillard
• There was a crowd there and when it dispersed, Fermi and I stayed
  there alone. Enrico Fermi and I remained. I shook hands with Fermi
  and I said that I thought this day would go down as a black day in the
  history of mankind.
• I was quite aware of the dangers. Not because I am so wise but
  because I have read a book written by H. G. Wells called The World
  Set Free. He wrote this before the First World War and described in it
  the development of atomic bombs, and the war fought by atomic
  bombs. So I was aware of these things.
• But I was also aware of the fact that something had to be done if the
  Germans get the bomb before we have it. They had knowledge. They
  had the people to do it and would have forced us to surrender if we
  didn't have bombs also.
• We had no choice, or we thought we had no choice.
Nuclear terrorism (1)




 • September 11, 2001?
 • What would happen if
   terrorists flew an
   aeroplane into a
   nuclear reactor?
Do we need nuclear power?




  We face a possible Energy Gap in the years to come.

          We need to reduce Carbon emissions!

   Difficult to see how we will sustain current levels of
    consumption without building new nuclear power.

               But we still have a choice…
Do we need nuclear power?




            Does Britian need nuclear power?

                  Please find an answer!
Nuclear Power
The UK Context
Fusion
The answer?



   • Collect interstellar hydrogen and turn it into helium

   • Build a fusion reactor bigger than the Earth!

   • Position the reactor about 93 million miles away

   • Call it the Super Universal Neutrino machine
The End




          Thanks for coming
           to the course.
           If you enjoyed
           it, please tell
           your friends and
           colleagues
The Pub
The Abercorn Arms
Church Road, Teddington
UK Nuclear Energy update




   AREVA and
   Electricité de
   France's (EDF)
   European
   Pressurized Reactor
   (EPR)
                           Westinghouse Link
   Westinghouse
   Electric Company's
   (WEC) AP1000
   pressurized water
   reactor (PWR)
What is Nuclear Power?




                          Nuclear
                   Positives & Negatives
Radioactive waste (1)
Low level waste



   • Low level waste
      – Not very radioactive
      – Much of it is
        ‘precautionary’
      – No problem really
Radioactive waste (2)
Intermediate level waste



   • Intermediate level waste
      – Very radioactive
      – Quite a lot of it
      – Many different physical
        forms
      – No problem with heat
      – Requires isolation for
        thousands of years
Radioactive waste (3)
High level waste



   • High level waste
      – Used fuel rods
      – Intensely radioactive
      – Requires cooling
      – Chemical mess
      – Requires ‘management’
        for around 50 years
      – Will remain intensely
        radioactive for tens of
        thousands of years
Electricity Generation
The case for nuclear power




     So maybe we should keep nuclear power for a while?

          What if one considers the supply of oil…
World Oil Production
(projections)
Oil prices will rise


   Table
World Oil Production
We are close to ‘the midpoint’




GigaBarrels of Oil
Annual Production
World Oil Production
(the gap)
Electricity Generation
The case for nuclear power




           But is oil relevant to this problem?
              (still plenty of gas and coal)
Electricity Generation in UK
Pros and Cons




                                                        CO2
   Type            Pros                 Cons
                                                       Kg/kWh

               Well suited to       Not popular
 Nuclear                                               0.010
            supplying base load    Waste Problem

             Clean, plentiful,    Fluctuating Supply
   Wind                                                0.001
            available in the UK       Unsightly?
Radioactive health risks
Radon
Radioactive health risks
Height above sea level

                             15 km     0.01 mSv
                                       per hour

                             10 km     0.005 mSv
                                        per hour



                Himalayas    7 km      0.001 mSv
                                        per hour

                             2.5 km   0.0001 mSv
               Mexico City              per hour
Electricity Generation in UK
1950




• Back in 1950
                               Crude Oil   Hydro
   – Basically just coal
                                10.4%      0.1%




                                              Coal
                                             89.5%
Electricity Generation   1990: 160 million tons
CO2 Emissions            2005: 150 million tons
                         2010: target: 135 million tons
Wind Power
Environmental Change Institute




                                        Percentage of maximum generation power
• Wind has problems of                                                           100

   – availability
   – variability                                                                 80

• Availability
                                                                                 60
   – On average a 3MW turbine only
     generates 1 MW
   – Sometimes, it generates nothing!                                            40
   – Needs conventional back up
• Variability                                                                    20

   – If wind speed changes
   – 40 to 30 mph: No problem                                                     0
                                                                                       0   10   20    30    40    50     60
   – 30 to 20 mph: Output halves!                                                          Wind Speed (miles per hour)
Sustainable Development
Commission



 Sustainable Development Commission
 The government’s independent watchdog on sustainable development
 Report March 2006

 “The two overriding concerns for Government are the need to:
 • reduce carbon dioxide (CO2) emissions as part of efforts to
   tackle climate change, and
 • increase confidence in the security of energy supply.”

               “Nuclear power is not the answer to tackling
                     climate change or security of supply”
What is Radioactivity(5)
Isotopes



• Nuclei with the same number
  of protons, but different
  numbers of neutrons are
  called isotopes
• Nuclei with an ‘unbalanced’
  ratio of protons and neutrons
  are unstable
• Instability is caused by
  electrical repulsion between
  protonsactually a couple more
  but don’t worry about them for
  now
What is Radioactivity (7)
Summary



   • Only nuclei with a ‘balanced’ number of protons and
     neutrons are stable

               Isotopes with          Isotopes with
             too many protons      too many neutrons
                Alpha decay            Beta decay
             Emission of fast        Emission of fast
           moving helium nucleus     moving electron

            And gamma radiation    And gamma radiation
Current UK Nuclear Capacity                                        Power Station     Capacity GW   Retirement
With retirement dates                                                Calder Hall        0.194         2003

                                                                    Chapelcross         0.196         2005

                                                                     Sizewell A         0.420         2006

• Current capacity is 12.4 GW                                       Dungeness A         0.450         2006

                                                                      Oldbury           0.434         2008
• Most of this will be retired by 2023
    – Possibly much earlier                                         Dungeness B         1.110         2008

                                                                       Wylfa            0.980         2010
• If we don’t replace it with nuclear
  power, what should we replace it                                 Hinkley Point B      1.220         2011
  with?
                                                                    Hunterston B        1.190         2011
    – Energy savings?
    – A CO2 free technology?                                         Hartlepool         1.210         2014

                                                                     Heysham 1          1.150         2014
• If we don’t replace the power
  stations with something, there will                                Heysham 2          1.250         2023
  be power cuts!                                                      Torness           1.250         2023

   http://www.dti.gov.uk/energy/nuclear/technology/history.shtml     Sizewell B         1.188         2035

				
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