Tuesday, January 28, 2020

Fusion Power for Sustainable Development

Fusion Power for Sustainable Development Introduction Sustainable energy is about using energy wisely and using energy generated from clean sources and clean technologies. This approach is first step to ensuring we have sustainable energy and technologies for present and future generations. Being efficient with our energy will reduce our household and business energy bills, reduce the amount of energy we need to produce in the first place and cut energy related greenhouse pollution. Sustainable energy isn’t just about producing energy to meet the demands, it also means that the energy sources are clean and don’t have a detrimental on the environment. This essay will discuss in-depth how fusion power is the solution the energy crisis which is currently being faced around the world. Fusion is a very clean, green source of power which doesn’t have a detrimental impact in the environment. Nuclear fusion In nuclear physics, nuclear fusion is a nuclear reaction in which two or more atomic nuclei collide at a very high speed and join to form a new type of atomic nucleus. During this process, mass is not conserved because some of the mass of the fusing nuclei is converted to photons (energy). Fusion is also the process that provides Sun and all other stars with their energy; the process involves the collision of atomic nuclei to release energy. Currently scientists and engineers are developing the technology that it can be used in power stations to meet the energy demands that are currently being faced globally. It is hoped that fusion will provide us with the solution for the current energy crisis and provide a clean renewable source of power for future generations. How fusion works In a fusion reaction, energy is released when two light atomic nuclei are fused together to form one heavier atom. This is the process that provides the energy powering the Sun and other stars, where hydrogen nuclei are combined to form helium. To achieve high enough fusion reaction rates to make fusion useful as an energy source, the fuel (two types of hydrogen – deuterium and tritium) must be heated to temperatures over 100 million degrees Celsius. At these extremely high temperatures the fuel becomes plasma. What is plasma? Plasma is the fourth state of matter with the others being solid, liquid and gas. a plasma is an ionized gas, a gas into which sufficient energy is provided to free electrons from atoms or molecules and to allow both species, ions and electrons, to coexist. Plasma is a gas that has been energized to the point that some of the electrons break free from, but travel with, their nucleus. Gases can become plasmas in several ways, but all include pumping the gas with energy. A spark in a gas will create plasma. A hot gas passing through a big spark will turn the gas stream into a plasma that can be useful. Plasma torches like that are used in industry to cut metals. The plasma is also extremely thin and fragile, and is significantly less dense then air. To keep the plasma from being contaminated and cooled by contact with material surfaces it is contained in a magnetic confinement system. Magnetic confinement is the approach that Culham and many other laboratories are researching to provide energy from fusion. A plasma of light atomic nuclei is heated and confined in a circular bottle known as a tokamak, where it is controlled with strong magnetic fields. A magnetic fusion device, the maximum fusion power is achieved using deuterium and tritium. These fuse to produce helium and high-speed neutrons, releasing 17.6MeV (megaelectron volts) of energy per reaction. This is approximately 10,000,000 times more energy than is released in a typical chemical reaction. A commercial fusion power station will use the energy carried by the neutrons to generate electricity. The neutrons will be slowed down by a blanket of denser material surrounding the machine, and the heat this provides will be converted into steam to drive turbines and put power on to the grid. The Tokomak The tokamak is a magnetic confinement system and is a key component which is required for a fusion reaction to take place. Tokomak the base on which the fusion reactors of the future will be build around. It was first invented by the soviet union during the 1960s and it was soon adopted by scientists and engineers around the globe. The joint European Torus(JET ) , which is located at the Culham Centre for Fusion Energy, is the largest and most powerful set up which is currently in operation. tokamak components and functions are as follows: The plasma is contained in a vacuum vessel. The vacuum is maintained by external pumps. The plasma is created by letting in a small puff of gas, which is then heated by driving a current through it. The hot plasma is contained by a magnetic field which keeps it away from the machine walls. The combination of two sets of magnetic coils – known as toroidal and poloidal field coils – creates a field in both vertical and horizontal directions, acting as a magnetic ‘cage to hold and shape the plasma. Large power supplies are used to generate the magnetic fields and plasma currents. Plasma current is induced by a transformer, with the central magnetic coil acting as the primary winding and the plasma as the secondary winding. The heating provided by the plasma current (known as Ohmic heating) supplies up to a third of the 100 million degrees Celsius temperature required to make fusion occur. Additional plasma heating is provided by neutral beam injection. In this process, neutral hydrogen atoms are injected at high speed into the plasma, ionized and trapped by the magnetic field. As they are slowed down, they transfer their energy to the plasma and heat it. Radiofrequency heating is also used to heat the plasma. High-frequency oscillating currents are induced in the plasma by external coils or waveguides. The frequencies are chosen to match regions where the energy absorption is very high (resonances). In this way, large amounts of power may be transferred to the plasma. Why fusion Power is needed By 2050, it is expected that will be a rise in global population from six billion to nine billion and better living standards could lead to a two to threefold increase in energy consumption. At this point in time, 80% of the developed worlds energy comes from fossil fuels. The ever increasing dependency on fossil fuels for generating power has lead to things such as global warming and acid rain and other damaging effects on our health and on the world we live in. Achieving fusion power Fusion is expected to become a major part of the energy mix during the second half of this century because it is seen by so many as being the â€Å"silver bullet† to the l energy problems which is currently plaguing the world . With sufficient funding, the first fusion power plant could be operating in the 2040s. To achieve this, first a series of development steps need to be taken, which are set out in the European fusion roadmap, published in 2013. CCFE is working with its counterparts around Europe to implement this plan, which would see fusion power on the grid by 2050. ITER is the next major international fusion experiment and a crucial step towards achieving commercial fusion energy. It is expected to prove the feasibility of electricity generation from fusion by releasing in the region of 500 megawattsof fusion power (from a 50 megawattinput) for up to 500 seconds. It will be the first fusion experiment to produce net power – ten times more than the amount required to heat the plasma. Demonstration Once the scientific and engineering systems have been tested on ITER, the next stage will be to build a demonstration fusion power plant which will integrate the finding of the research . Designs are already advanced for this prototype machine, known as ‘DEMO. The demonstration is expected to produce in the region of two gig wattsof electrical power to the grid, a similar output to a standard electrical power plant, and could be online in the 2040s. If these trials are successful, it will lead to the first generation of commercial fusion power stations being put into commission. Advantages of fusion power The world needs new, cleaner ways to meet our ever increasing energy demand, as concerns grow over climate change and declining supplies of fossil fuels. Power stations using fusion would have a number of advantages: No carbon emissions. The only by-products of fusion reactions are small amounts of helium, which is an inert gas that will not add to atmospheric pollution. Abundant fuels. Deuterium can be extracted from water and tritium is produced from lithium, which is found in the earths crust. Fuel supplies will therefore last for millions of years. Energy efficiency. One kilogram of fusion fuel can provide the same amount of energy as 10 million kilograms of fossil fuel. No long-lived radioactive waste. Only plant components become radioactive and these will be safe to recycle or dispose of conventionally within 100 years. Safety. The small amounts of fuel used in fusion devices (about the weight of a postage stamp at any one time) means that a large-scale nuclear accident is not possible. Reliable power. Fusion power plants should provide a baseload supply of large amounts of electricity, at costs that are estimated to be broadly similar to other energy sources. Disadvantages of fusion power Unproven on a large commercial scale. No full scale production expected till at least 2050 The power plants would be expensive to build Requires extremely high temperatures. Could produce a net negative amount of energy If cold fusion could be achieved, it would be much easier to implement. The billions in research funding could be spent on renewables instead What is Cold Fusion? Cold fusion describes a form of energy generated when hydrogen interacts with various metals like nickel and palladium. Cold fusion is a field of condensed matter nuclear science CMNS, and is also called low-energy nuclear reactions LENR, lattice-assisted nuclear reactions LANR, nickel-hydrogen exothermic reactions Ni-H, and quantum fusion. The name cold fusion comes from the idea that the temperatures involved are relatively ( room temperature in some instances) low in comparison to those of a fusion reactor which are in excess of a few thousand degrees. Cold fusion gained attention after reports in 1989 by Stanley Pons and Martin Fleischmann, at the time one of worlds leading electrochemists,[1] that their apparatus had produced excess heat, of a magnitude they asserted would defy explanation except in terms of nuclear processes. They further reported measuring small amounts of nuclear reaction byproducts, including neutrons and tritium.[2] The small tabletop experiment involved electrolysis of heavy water on the surface of a palladium (Pd) electrode. The reported results received wide media attention,[3] and raised hopes of a cheap and abundant source of energy.[4] Many scientists tried to replicate the experiment with the few details available. Hopes fell with the large number of negative replications, the withdrawal of many positive replications, the discovery of flaws and sources of experimental error in the original experiment, and finally the discovery that Fleischmann and Pons had not actually detected nuclear reaction byproducts. In 1989, a review panel organized by the United States Department of Energy (DOE) found that the evidence for the discovery of a new nuclear process was not persuasive enough to start a special program, but was sympathetic toward modest support for experiments within thke present funding system. Pons and Fleischmann, skipped the typical route of publishing their study and results in a peer-reviewed science journal because of the pressure they were under from the university of Utah to secure a patent for this potential cash cow which could bring the university a significant amount media attention and flame for the Pons and Fleischmann, instead they take it directly to the press and public. Because they decided to take a unconvential root as to how they published their finding that lead others to question how authentic the information they were being given was. When many scientists from around the world tried to replicate the results from Pons’ without any success and questions began to be asked about the accuracy of the data which they had collected from their cold fusion experiment and this is what ultimately lead to their downfall. Recent developments in cold fusion Andrea Rossi a Italian scientist has said to have created a device called Energy Catalyser (E-cat for short) , is said to be a device â€Å"which purports to use cold fusion to generate vast amounts of power has been verified by a panel of independent scientists†. The research paper, which hasn’t gone through undergone peer review as of yet, seems to confirm both the existence of cold fusion, and its potency: The cold fusion device being tested has roughly 10,000 times the energy density and 1,000 times the power density of gasoline.

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