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The Tokamak Fusion Test Reactor (TFTR) was first proposed in 1973 and began construction in 1976. The rector began its operation in 1982 and continued until 1997. Through this time it operated first off of just DD reactions and then in 1993 it changed to D-T fusion. TFTR operated with D-T for over 3 years, achieving a peak fusion power of 10.7 MW, producing over 1 GJ of fusion energy and providing a demonstration of the feasibility of operating a fusion power plant. As a result of its overwhelming success it demonstrated that “fusion research is ready to advance to the study of burning plasmas.” From the above picture two types of fusion reactions are shown. The one two the left is the reaction that TFTR utilizes in its chamber. For this process to occur the plasma in the chamber must be heated to a sufficient temperature, which is a minimum of 20keV. Some of the methods used to reach this energy state are Electrical Resistance (ohmic) heating, Neutral Beam Injection (NBI) heating, electron magnetic wave heating, adiabatic compression of plasma and alpha particle heating in D-T plasma. Electrical Resistance heating or ohmic heating is a method that utilizes the electrical conductivity of the plasma. This is done by passing a current through the plasma, which is a similar heating process that an electric light bulb or an electric heater experience. The heat produced by this process is dependent on the amount of resistance that is generated by the plasma and the current. A problem that develops with this method is that when the plasma is heated up the resistance drops and the ohmic heating process becomes less effective. As a result of this ohmic heating is not a suitable heating process by its self. The reason for this is that the maximum plasma temperature attainable by this process is 20 to 30 million degrees Celsius which is far to less for fusion to be attained. The NBI is an acceleration of ions which are then neutralized and cross a magnetic field to enter plasma (100keV in TFTR). ). "Neutral-beam injection involves the introduction of high-energy (neutral) atoms into the ohmically (heated, magnetically) confined plasma. The atoms are immediately ionized and are trapped by the magnetic field. The high-energy ions then transfer part of their energy to the plasma particles in repeated collisions, thus increasing the plasma temperature." The electron magnetic wave process increases the heat in the chamber by launching waves near the ion cyclotron frequency into plasma to heat ions. A cyclotron is “a circular particle accelerator in which charged subatomic particles generated at a central source are accelerated spirally outward in a plane perpendicular to a fixed magnetic field by an alternating electric field.” A cyclotron is capable of generating particle energies between a few million and several tens of millions of electron volts. In radio frequency heating, high frequency waves are generated by oscillators outside the torus. When the waves produce a certain frequency or wavelength their energy can be transferred to charged particles in the plasma. Theses charged particles then collide with other plasma particles, which increases the temperature of the bulk plasma. In an operating fusion reactor part of the energy needed to sustain the fusion process well be provided by the energy generated by the rector itself. This is achieved by introducing fresh deuterium and tritium into the chamber. For this to occur the plasma needs to be heated to an initial temperature of 10 million degrees Celsius. The TFTR didn’t produce sufficient fusion energy to maintain this plasma temperature (nor has any other tokamak currently attained this level of efficiency). As a result of this the fusion chamber operates in short pulses and the plasma must be heated afresh for every pulse. This image is a depiction of a plasma fusion chamber after an injection of frozen D2 pellets. From the above pictures one can gain a perspective of what the future hold for industrial tokamak energy providers. Though TFTR was not able to achieve a fusion power output equal with the plasma heating power input, most scientist are very confident that this will be accomplish do to how close they have come to attaining this goal. From the results of the TFTR it suggest that D-T plasmas have better confinement that their D-D counterparts. As a result of this understanding scientist are becoming confident that they will be able to build a fusion reactor which will generate gigawatts of surplus energy. One of the main challenges now is to do it in an environmental and cost-effective manner. For the future of plasma fusion reactors to progress one of the major challenges that persist is sustaining the multi-megawatt power output for a second or longer. This has become extremly crucial do to the known plasma instabilities which occur much more quickly. These instabilities have been one of the most challenging advercities to the program.