Nuclear Fusion and energy utilities Created by S. Lumley creative PowerPoint labs

What is Fusion? Fusion is a nuclear reaction that converts matter into energy It is the same nuclear process that fuels the sun, and so is extremely efficient on usage of fuel. Where conventional Nuclear fission splits heavy atoms into smaller ones, fusion combines smaller atoms into larger ones.

How do you get energy from matter? Energy is released in nuclear reactions, when atoms are converted more stable atoms Some atoms are more stable, because they have a larger amount of energy binding them, together (binding energy) When atoms are converted into more stable atoms the difference in binding energies is released, making the atoms produced, move faster. This is manifested as heat.

Initiating the reaction In order for 2 nuclei to fuse, they must come close enough for the strong nuclear force to overcome the electro-magnetic force that pushes them apart. Velocity Velocity Strong Nuclear force Strong Nuclear force Electromagnetic force As the particles get closer and closer together, the repulsive force between them increases, and therefore they will slow down When the particles, get close enough, the strong nuclear force takes over, and the particles are fused together

Problems with initiation Although the energy released by the reaction is tremendous, a sizable quantity of energy is needed to overcome the initial repulsion In order for the average energy of the particles to be greater than the required 0.14MeV, the fuel must be at over 100,000,000 degrees. At this temperature, the atoms are completely ionised, and are in the fourth state of matter: plasma.

Plasma solutions As the plasma is ionised, there are no neutral component of the plasma. This means it can be influenced by magnetic fields. Particles follow Circular paths around the magnetic field lines, so if it is already moving forwards… Magnetic flux line This means the plasma can be contained, and prevented from touching cooler materials by magnetic fields, however…

Container shapes The shape of the magnet is crucial… In any cylindrical magnet, the plasma would fly out the ends…

The solution- The Tokamak The toroidal (donut) shape of the tokamak means that there are no “ends” for the plasma to come out.

Current Tokamaks Unfortunately, tokamaks as yet, have not been able to reach the break even point, but it is only a matter of time…

Advantages and disadvantages of fusion as an electricity source Fuel is very abundant Not much Fuel is required per Mw produced Much safer than other fuel based methods of energy production No greenhouse gas emissions or radioactive waste Waste products are harmless Is more reliable than renewable energy sources Running costs would be comparatively small Would not require large areas of land or coast to be set aside. Disadvantages Would have extremely high initial capital investment Operators would require a much higher level of education and training than other electricity production methods Would be a source of thermal pollution The reactor itself would be radioactive after long periods of operation. (although they would still become safe again in a much shorter time than the half-lives of some fission wastes)

Fuel Fuel Quantity 842 Kg 120Kg 525 Kg 36g 0.16g a year coal The fuel (deuterium) is very common in seawater, and can easily be extracted in commercial quantities, although very little is required. The average Briton uses this much fuel a year to power their homes. Fuel Quantity coal 842 Kg Oil 120Kg Gas 525 Kg Uranium 36g However, all of this would be the equivalent to just.. 0.16g a year

Improved Quality of life Specific Advantages Fusion Money Power surplus Leads to Leads to Fusion Electric Cars Leads to Drastic drop in greenhouse gas emissions Less dependence on oil £Cheap£ £Fusion£ Industrialisation of less economically developed countries Improved Quality of life Could Allow Leads to