Dr Ian Falconer School of Physics, University of Sydney Some of the slides shown in this presentation were provided by: Dr Joe Khachan, University of Sydney Professor John O’Connor, University of Newcastle I gratefully acknowledge their permission to use these slides

Fusion: our energy future ?

FUSION The energy that drives the stars Can it also be harnessed on earth to provide the energy our society needs?

The world has real energy problems (And fusion energy MUST be a big part of the solution) What is fusion? How do we harness fusion energy? Why fusion? And what IS fusion?

The world is running out of (cheap) energy - i.e. fossil fuels and CO 2 from fossil fuels is a greenhouse gas For these reasons, we URGENTLY need a energy source to replace fossil fuels (and it must be “portable” - like petrol – so it can be used in cars and trucks)

The world has real energy problems We are fast running out of oil (and natural gas) Burning of fossil fuels generates carbon dioxide (CO 2 ) For every tonne of oil or coal used for generating energy, around THREE tonnes of CO 2 are generated Per capita energy consumption increases as nations become wealthier Think about India and China

The case for fusion energy : standard of living Growth of Australia’s Primary energy consumption and GDP

The case for fusion energy : standard of living

How long will it last? Oil ~ years Natural gas ~ years Nuclear fission energy (U 235 burners) 50 to ~100 years Nuclear fission energy (breeder reactors) Thousands of years Solar, wind, tidal energy Renewable Fusion energy Millenia

We have only limited oil and natural gas resources Not only do these fuels generate CO 2, but are a valuable feedstock for the chemical industry The combustion of coal must necessarily generate the greenhouse gas CO 2 Nuclear energy is another limited resource, and waste disposal and proliferation are problematic – at least politically The “renewables” are intermittent resources, which require extensive – and expensive - energy storage capacity if the are to provide energy “on tap” Fusion energy MUST be part of the solution

What is fusion?

Fusion energy powers the Sun

Chemically these isotopes are the same, but the deuterium and tritium store considerable energy in their nuclei – this is the energy that holds the nuclei together The release of the energy stored in the nuclei of “heavy hydrogen” atoms - deuterium and tritium Hydrogen: nucleus consists of 1 proton Deuterium: nucleus consists of 1 proton and 1 neutron Tritium: nucleus consists of 1 proton and 2 neutrons What is fusion?

The Most Promising Fusion Reaction

D-D Fusion Reaction Proton Neutron

Where do the fuels come from? Deuterium is present in all “natural” hydrogen. There is 1 atom of deuterium for every 6,000 atoms of hydrogen. Water is thus an abundant source of deuterium Tritium also occurs naturally, but in a fusion reactor will be created by bombarding a blanket of lithium surrounding the core of the reactor Lithium is also abundant in nature: Australia has 60% of the world’s proven lithium reserves

“Breeding” tritium Lithium + neutron → Tritium + Helium + ENERGY Liquid lithium will be used as a coolant in fusion reactors. It will absorb the energy of the neutrons, and at the same time “breed” tritium and produce more energy

How do we harness fusion energy?

Bang a deuterium nucleus and a tritium nucleus HARD together so they “fuse” A mixture of deuterium and tritium gases must be heated to a very high temperature if the nuclei are to “fuse” – about 100 million degrees! Under these conditions all the atoms are ionized and form a PLASMA These high temperatures can only be achieved if the gases are contained in a “bottle” constructed from a really strong magnetic field And a high density of colliding nuclei is required if we are to get more fusion energy from the reactor than we put into it

Magnetic Confinement

Toroidal field produces greater confinement

Tokamak confinement

Inside a TOKAMAK

Tokamak Operating

Q = P out /P in ~1 “Breakeven” regime : Eg. Joint European Tokamak : “Ignition” regime, fully self-sustained : Power Plant. “Burning” regime : plasma dominantly self-heated by fusion born alpha’s 1997 : Q=0.7, 16.1MW fusion Progress in magnetically confined fusion ITER

ITER – “the way” International Thermonuclear Experimental Reactor An international project to produce a prototype fusion reactor ITER partners European Union Japan China Russian Federation USA Korea India (and possibly Brazil – and Canada, Mexico and Kazakhstan)

The ITER project Fusion power = 500MW Power Gain > 10 Temperature ~ 80 million  C Construction cost $10 billion, 10 year operation $6 billion Fiscally, world’s largest science experiment Cadarache, France Consortium of 7 nations

ITER Person ITER – the next generation tokamak Design completed – construction has just commenced

Aims of the ITER project Produce and study inductively-driven, burning plasma at Q =P out/ P in  10 ( MW) for an “extended” time, ~ 400 s Produce and study burning plasma with non-inductive drive Q   5 Integrate essential fusion reactor technologies: superconducting magnets, high heat flux components, remote handling Test reactor components: eg tritium breeding module concepts (neutron power load > 0.5 MW m -2, fluence > 0.3 MW year m -2 ).

Fusion is part of our Energy Future But….. When? 2016 First plasma 2020 First DT “burn” 2021 Q = Construction of DEMO to commence 2033 Operation of DEMO to commence 2045 Construction of power plant to commence 2055? Power plants operates!!!

NOWASSEMBLY STARTSFIRST PLASMA

Source: Accelerated development of fusion power. I. Cook et al ITER today’s experiments materials testing facility (IFMIF) demonstration power-plant (DEMO) commercial power-plants R &D on alternative concepts and advanced materials Beyond ITER…

Comparison to CPU transistors

The pros and cons of fusion energy PRO “Unlimited” fuel supply Little waste produced CON Relatively expensive (High construction and maintenance costs) Structure highly radioactive – for a short time

0.001 $ / kWhr internal costs: costs of constructing, fuelling, operating, and disposing of power stations external costs: “estimated” impact costs to the environment, public and worker health, Prospects for fusion electricity, I. Cook et al. Fus. Eng. & Des , pp25-33, 2002 The case for fusion energy : fusion economics

Fusion: a safe, relatively inexpensive source of energy for which we have an inexhaustible supply of fuel ITER is – undoubtedly – “the way”

Why isn’t Australia – pioneers in the field of fusion physics - involved in the ITER project??

THE END

LHC: the Large Hadron Collider 7 TeV = 7,000,000,000,000 eV