Protons for Breakfast

Protons for Breakfast

Week 6

Do we need nuclear power?

In the event of an alarm sounding…

Nuclear PowerThe UK Energy Scene

Renewables versus

Nuclear

Diversity of Supply

Sustainability

Cost!

Carbon

Waste!

Security of Supply

Link to Weapons

ChernobylCarbon

Carbon

Carbon

Carbon

Carbon

Carbon

Carbon

Nuclear PowerThe UK Context

• How is electricity generated?• How much electricity does Britain need and where does it come from?• Nuclear Power Stations are due for closure

– Energy Gap?

• How to replace the lost generating capacity? – Reduce demand, Wind Power, Tidal Barrage, Solar Power?

• Nuclear Power?– Radioactivity & Nuclear Fission– Pros and Cons

Tonight’s TalkElectricity 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 PearceLaurie WinklessLindsay ChapmanLloyd EnglandMateusz SzymanskiMatthew TedaldiNeelaksh SadhooPaul CarrollPeter QuestedPeter WoolliamsRainer WinklerRichard GilhamRobert GoddardRobin UnderwoodRuth MontgomerySharmila HansonStephanie BellThomas Korrison

Andrew HansonArzu ArincAveril HortonBufa ZhangClive ScogginsDaniel GittingsDavide Di MaioDeborah LeaEleanor BakhshandeiarEmma WoolliamsGianluca MemoliJacquie ElkinJames MiallJeff FlowersJenny WilkinsonJian WangJoanna LeeJohn MakepeaceJohn Mountford

ExpertsMartin Milton

Paul Quincy

Nigel Fox

Andrew Gregory

Andrew Beardmore

Bob Clarke

Kevin Lees

Alan DuSautoy

Alan Turnbull

Nigel Jennett

John Makepeace

Simon Jerome

Electricity

Eeeee - lec- tric-ity

Where does it come from?

Tonight’s Talk

How is electricity generated?

How is electricity generated? (1)

Nuclear Coil turning in a magnetic field

Turbine driven by hot steam

Nuclear Fission

U + n ???Stellar

Type of station

Electricity made by…

What makes coil turn?

Energy Source Ultimate Source

Coal Coil turning in a magnetic field

Turbine driven by hot steam

Chemical

C + O2 CO2Solar

Gas Coil turning in a magnetic field

Turbines driven by hot gas and steam

Chemical

CH4 + 2O2

CO2 + 2H20

Solar

Wind/Wave Coil turning in a magnetic field

Turbine driven by air or water

Nuclear Fusion 4H He Solar

Mamod Coil turning in a magnetic field

Pistons driven by steam

Chemical

C + O2 CO2?

Mamod

While the station powers up…

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whether it has been successful, and decide what to change and what to keep the same

Ticking the boxes is important, but your comments are especially valuable.

How much electricity do we need?

Electricity Generation in UK Daily variations in 2001/2002

gigawatt (GW) billion watts =109 W= 1000000000 W

=10 Million Light bulbs

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Maximum Winter Demand

1 gigawatt (GW)

billion watts =109 W

=10 Million 100 W light bulbs

Roughly speaking 1 large power station

Electricity Demand 2001-2009Mmmm. Looks near to 60 GW peak demand!

Electricity Generation in UK Daily variations in 2001/2002

Required generating

capacity (GW)Summer Winter

Peak 45 60

Base 25 30

Daily Maximum- Daily Minimum 30

1 gigawatt (GW)

billion watts =109 W

=10 Million 100 W light bulbs

Roughly speaking 1 large power station

How do we meet this demand?

Energy Consumption Right Now!

Electricity Generation in UK

Typical Winter DemandThursday 6th December 2001Figure 2.5(b) - Typical Winter Demand (Thursday 6th December 2001)

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Nuclear

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Large Coal

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Time of Day

Electricity Generation in UK Data from 2004

Coal33%

Oil1%Gas

40%

Nuclear19%

Hydroelectric1%

Wind/Biomass/Landfill Gas3.5% Imports

2.5%

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Current UK Nuclear CapacityHistory and Future

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FutureHistory

• Decline could be faster

• Energy Gap?

Electricity Generation in UK 2020

• Nuclear will decline

• Renewables will increase– but by how much?

• No shortage of coal and gas – See BP Energy Review– Cost? – Security of supply?

Coal33%

Oil1%Gas

40%

Hydroelectric1%

Wind/Biomass/Landfill Gas3.5% Imports

2.5%

Nuclear??????????????????????????????

http://www.bp.com/productlanding.do?categoryId=6929&contentId=7044622

Alternatives?

Is it possible to:

• Reduce Gas and Coal generation• Increase Renewables• Avoid replacing Nuclear Power

stations

Can we reduce demand?

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10Nuclear

Gas &

Coal

Renewable60

Annualised Electricity Consumption

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What to do?Reduce Demand

• My family’s electricity usage for the last four years• Can we make people and businesses use less?

electricity? • Price• Rationing

2000 kWh20% reduction£260 a year

Electricity Usage in UK 2004

• Several easy wins

Domestic29%

Industry29%

Agriculture 1%Transport 2%

Public Adminsitration

5%

FuelIndustries

8%

Losses8%

Commercial18%

Lighting

Universal use of CF light bulbs will eliminate the need for

1 large power station

Alternatives?

So reducing demand could help.

What can wind provide?

Most people would think this is wildly optimistic!

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Wind Power (1)UK Wind in 2007

• UK has some of the best sites in Europe

• Currently– 154 Projects– 1900 Turbines– 2.293 GW

• Plus1.3 GW under construction4.6 GW planning approved9.8 GW seeking approval

18 GW in a few years time

Wind Power Could we get 10% (5.3 GW) of electricity from wind?

• Retain 3 GW of coal fired capacity as ‘backup’

3 GW

13 GW

• Build 5000 of the largest wind turbines

•Wind has problems of

–availability

–variability

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

5.3 GW

Alternatives?

So wind can provide a lot of power,

but we can’t control when it is generated

Could we store some of the power?

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WIND

Very ambitious, but achievable…

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 UKPumped Storage

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Energy Use

0 to 1.3 GW in 12 seconds

Other Alternatives?

So reducing demand can help.

And wind and stored energy could help too

What about solar electricity?

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WINDWIND

&STOR

Solar Photo VoltaicStep 1

• Put this on your roof• 9 m2 • Twickenham

Solar Photo Voltaic Step 2

• Put these in your house

Solar Photo VoltaicHey presto!

• 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 %

Daily generation rate

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PLUS

GOVERNMENT

CASHBACK!

£0.35 for every unit

fed back to the grid!

AMAZING FACT!

In the summer months –

there is more solar energy

at UK latitude than EVER

reaches the Equator!

Other Alternatives?

So reducing demand can help.

And wind and stored energy could help too.

Even solar energy can help

Mainly in Summer…50

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WINDWIND

&STOR

SUN

Severn Tidal Barrage

Could generate 10% of UK

demand

5 GW

£15B

Nuclear Fusion

Nuclear Fusion

Nuclear Fusion What is it?

proton

neutron

deuteriumnucleus10,000 ºC1,000,000 ºC100,000,000 ºC

Fusion

JEThttp://www.jet.efda.org/

ITERhttp://www.iter.org/default.aspx

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

Probability of Engineering Feasibility by 2100???? 5%????

Summary

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WINDWIND

&STOR

SUN

TIDE

Action Effect (GW)Reducing demand 10

wind and stored energy 10tidal barrage or lagoons 10

Solar energy 3And there are many other

possibilities…?

Mmm…Every one of these figures looks

optimistic…

Nuclear PowerThe UK ContextThe UK is committed to

34% reduction in CO2

emission by 2020

Renewables versus Nuclear Energy costs

likely to rise in

long term

The UK is committed to

80% reduction in CO2

emission by 2050Sustainable and diverse supplies are more secureRenewables AND Nuclear

Carbon Crunch

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WINDWIND

&STOR

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TIDE

Method of generation

Kilograms of CO2 emitted for every 1

kWhe supplied:

Coal 1

Gas (CCGT) 0.5

Wind 0.01

Tide 0.01

Nuclear 0.01

Summary

• 11 GW of CO2-free generating capacity will be retiring in the next 17 years

• Even replacing it will not reduce CO2 emissions

So let’s find out about nuclear power!

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WINDWIND

&STOR

SUN

TIDE

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 ChamberSupermarket Radioactivity

Remember this…

Electromagnetic waves

Atoms Heat

Electricity

‘Nuclear’ refersto the nucleus

of atoms

Powers of Ten Nuclear Power

Very Very

Large

100

103

106

109

1012

101510-3

10-6 1018 1024 1030 1036

1021 1027 103310-15 10-9

10-18 10-12

Very Very Small

Human Relationships

Distance to the Sun

Tallest Mountain

Diameter of the Earth

Atoms & molecules

Microbes

The issues surrounding nuclear power involve

physical processes with length scales spanning 25

powers of 10!

Nucleiof atoms

How are atoms made?

proton

Interact by the short range ‘strong’ force – not electrical

Electrical Repulsion

How are atoms made?

What is Radioactivity(2)…

• Normally nuclei act as heavy point-like centres for atoms

• 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

Nucleus


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

• This determines the chemical and physical properties of the atom

• But the number of neutrons in a nucleus can vary

http://www.immr.tu-clausthal.de/geoch/pse/pse.map

Radioactive

0.01%

What is Radioactivity(4)Example 39K, 40K and 41K

• Potassium is 2.4% of the Earth’s crust• Natural potassium (symbol K) has three isotopes

39K19 protons

20 neutrons

20 + 19 = 39

Same number of protons

Different numbers of neutrons

40K19 protons

21 neutrons

21 + 19 = 40

41K19 protons

22 neutrons

22 + 19 = 41

93.3% 6.7%


Three types of radioactivity • Named with the Greek a, b, c

alpha, beta, gamma• Nuclei with a ‘balanced’ number of protons and neutrons are stable

Isotopes with too many protons

Isotopes withtoo many neutrons

Alpha decay Beta decay

Emission of fast moving helium nucleus

Emission of fast moving electron

And gamma radiation And gamma radiation

Charge oscillations in nucleus

What is Radioactivity(8)Alpha () Decay

Alpha particlegamma ray

Nucleus with too many protons

Charge oscillations in nucleus

What is Radioactivity(8)Beta () Decay

gamma ray

Nucleus with too many neutrons

Beta particle

Radioactivity

What are the health risks

of ionising radiation?

Radioactive health risksIntroduction

• Radioactive emissions alpha, beta, 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 risksMeasurement units

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

Sievert

Radioactive health risksAnnual average UK dose

Source Dose (mSv)

Natural

Cosmic 0.26

Gamma rays 0.35

Internal 0.3

Radon 1.3

Artificial

Medical 0.37

Occupational 0.007

Fallout 0.005

Products 0.0004

Discharges 0.0002

Total 2.6

• Average annual dose to the UK population from all sources

• Average 0.0026 Sieverts• Average 2.6 milliSieverts• About 7 microSieverts /day

Radioactive health risksSources

From foodAbout 15 million

potassium 40 atoms and 7000 natural uranium

atoms disintegrate inside us each hour

From soil and building materialsOver 200 million gamma rays pass through the average individual each hour

From the airAbout 30,000 atoms disintegrate each hour in our lungs and give of alpha, beta, and gamma radiation

From the skyAbout 100,000 cosmic ray neutrons and 400,000 secondary cosmic rays penetrate the average individual every 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

Fissile? No Yes

natural uranium. 99.3% 0.7%

neutrons 238 – 92 = 146 235 – 92 = 143

Nuclear Fission (3)Uranium Fission

• 235U + n >>> 236U + n

• After a short while

• 236U >>> fragments + 3 n

Nuclear Fission (4)Chain reaction

• 235U + n >>> 236U >>> Fragments + 3n


• Each fission produces 3 extra neutrons on average

– If more than one neutron produces an additional fission• The rate of fission increases• If uncontrolled leads to a nuclear explosion

– If less than one neutron produces an additional fission• Then the rate of fission decreases• Nuclear reactions will die out

– If exactly one neutron produces an additional fission• Sustainable nuclear reaction

Nuclear Power Stations

UK Nuclear Energy update

AREVA and Electricité de France's (EDF) European Pressurized Reactor (EPR)

Westinghouse Electric Company's (WEC) AP1000pressurized water reactor (PWR)

Westinghouse Link


Nuclear Positives


Radioactive Emissions

Energy Density

Very low CO2

emissionsReliability

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


Nuclear Negatives


Waste!

Terrorism

Link to

Weapons

Chernobyl


Chernobyl

Catastrophic ExplosionChernobyl

• 26 April 1986• 31 dead Immediately• Ultimate death toll

– 100?– 15,000?

Chernobyl Effect on UK

Chernobyl

Fall out from atmospheric

atomic weapons testing

Annual dose

(micro Sieverts)

1951 1988

Total radiation dose was 20 times less than the dose from the atmospheric bomb tests from 1945 to 1963.

Year


Waste!


• 235U + n >>> 236U >>> Fragments + 3n

These fragments are intensely

radioactive

Waste (4)Carbon versus Nuclear

WasteRadioactive

WasteCarbon Waste

(CO2)

Cost Large, but calculable

Incalculable

Worldwide Physical Mass

<1 million tonnes cumulative total

>30 billion tonnes per year

Manageable Probably Probably not


Link to

Weapons


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

• Chicago• 3:25 P.M. December 2,

1942• Nuclear Age began• Gain = 1.0006

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)Hopes

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 Fission (6)Fears


Terrorism

Nuclear terrorism (1)

• September 11, 2001? • What would happen if

terrorists flew an aeroplane into a nuclear reactor?


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…

Summary


The Answer!

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 (or SUN)

UK Nuclear Energy update

AREVA and Electricité de France's (EDF) European Pressurized Reactor (EPR)

Westinghouse Electric Company's (WEC) AP1000pressurized water reactor (PWR)

Westinghouse Link


Nuclear

Positives & Negatives


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

• Chicago• 3:25 P.M. December 2,

1942• Nuclear Age began• Gain = 1.0006

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)Hopes

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 Fission (6)Fears


Sounds like a lot of trouble: Why bother?

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)


OK so nuclear power is quite interesting.Are there any downsides?

• Link to nuclear weapons• Possibility of catastrophic explosion• Radioactive waste• Possibility of nuclear terrorism

Catastrophic ExposionChernobyl

• 26 April 1986• 31 dead Immediately• Ultimate death toll

– 100?– 15,000?

Chernobyl Effect on UK

Chernobyl

Fall out from atmospheric

atomic weapons testing

Annual dose

(micro Sieverts)

1951 1988

Total radiation emissions were 20 times less than the emissions from the atmospheric bomb tests from 1945 to 1963.

Year

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

Radioactive waste (4)Amounts in cubic metres

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

Type of Waste

Year

2000

Year

2030

Low 424,000 1,411 ,000

Intermediate 100,000 260 ,000

High 1,200 3,000

Amounts in cubic metres

Nuclear terrorism (1)

• September 11, 2001? • What would happen if

terrorists flew an aeroplane into a nuclear reactor?

Do we need nuclear power?You need to decide?


Consider • Our need to reduce carbon dioxide emissions• The risks & benefits of nuclear technology

– Do we want all countries to have nuclear power?• The effect on renewables

– Undermining or supporting?• The need to make decisions soon

– Build the next generation of nuclear power stations?– Or not?



Please find an answer!

FusionThe 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 (or SUN)

The End

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The Pub

Resources

Unused Slides

Electricity GenerationThe 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

http://www.peakoil.net/uhdsg/WORLD_SUMMARY_html.htm

World Oil ProductionWe are close to ‘the midpoint’

GigaBarrels of OilAnnual Production

World Oil Production(the gap)

Electricity GenerationThe case for nuclear power

But is oil relevant to this problem?

(still plenty of gas and coal)

Electricity Generation in UK Pros and Cons

Type Pros ConsCO2

Kg/kWh

NuclearWell suited to

supplying base loadNot popular

Waste Problem0.010

WindClean, plentiful,

available in the UKFluctuating Supply

Unsightly?0.001

Radioactive health risksRadon

Radioactive health risksHeight above sea level

0.01 mSv per hour

15 km

0.005 mSv per hour

10 km

0.001 mSv per hour

7 km

0.0001 mSv per hour

2.5 km

Mexico City

Himalayas

Coal89.5%

Crude Oil10.4%

Hydro0.1%

Electricity Generation in UK 1950

• Back in 1950– Basically just coal

Electricity GenerationCO2 Emissions

1990: 160 million tons

2005: 150 million tons

2010: target: 135 million tons

Wind PowerEnvironmental Change Institute

• Wind has problems of– availability– variability

• Availability– On average a 3MW turbine only

generates 1 MW– Sometimes, it generates nothing!– Needs conventional back up

• Variability– If wind speed changes– 40 to 30 mph: No problem– 30 to 20 mph: Output halves!

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Sustainable Development Commission

Sustainable Development CommissionThe government’s independent watchdog on sustainable developmentReport 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

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

What is Radioactivity (7)Summary

Isotopes with too many protons

Isotopes withtoo many neutrons

Alpha decay Beta decay

Emission of fast moving helium nucleus

Emission of fast moving electron

And gamma radiation And gamma radiation

Current UK Nuclear CapacityWith retirement dates

• Current capacity is 12.4 GW

• Most of this will be retired by 2023– Possibly much earlier

• If we don’t replace it with nuclear power, what should we replace it with? – Energy savings?– A CO2 free technology?

• If we don’t replace the power stations with something, there will be power cuts!

http://www.dti.gov.uk/energy/nuclear/technology/history.shtml

Power Station Capacity GW Retirement

Calder Hall 0.194 2003

Chapelcross 0.196 2005

Sizewell A 0.420 2006

Dungeness A 0.450 2006

Oldbury 0.434 2008

Dungeness B 1.110 2008

Wylfa 0.980 2010

Hinkley Point B 1.220 2011

Hunterston B 1.190 2011

Hartlepool 1.210 2014

Heysham 1 1.150 2014

Heysham 2 1.250 2023

Torness 1.250 2023

Sizewell B 1.188 2035

Quiz

• 210Po is a radioactive isotope of polonium with 82 protons and 128 neutrons making a total of 210 nuclear particles

What is polonium 210?

• Po-lonium 210 caused Po™ to be a bit strange

• Polo-nium 210 is the key ingredient in Polo™ mints

Documents

Protons for Breakfast