inertial confinement fusion

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The Future Of Energy Isn’t Fossil Fuels Or Renewables, It’s Nuclear Fusion

“Nuclear fusion as a power source has never been given the necessary funding to develop it to fruition, but it’s the one physically possible solution to our energy needs with no obvious downsides. If we can get the idea that “nuclear” means “potential for disaster” out of our heads, people from all across the political spectrum just might be able to come together and solve our energy and environmental needs in one single blow. If you think the government should be investing in science with national and global payoffs, you can’t do better than the ROI that would come from successful fusion research. The physics works out beautifully; we now just need the investment and the engineering breakthroughs.”

Climate science is a hotly debated area, with many disputing the robustness and ethical motivations of the scientists in the field. But even if you throw everything we know about carbon dioxide, global warming, and climate change away, there’s still an energy crisis coming in the long term. The fact is, fossil fuels will someday, hundreds of years from now, run out if we extract and burn them all. Meanwhile, solar, wind, hydroelectric and other renewables will forever be inconsistent, and the infrastructure needed for using both generates large amounts of pollutants. But there is one power option that could satisfy everybody, while eliminating both pollution and the risks of running out of fuel or power inconsistency: nuclear fusion. While nuclear fission does have substantial downsides, there’s no risk of a meltdown with fusion.

All we need to do is reach the breakeven point, and we have four different approaches currently in progress. Come get the science today!

anonymous asked:

Are there different kinds of ways to create fusion?

I’m glad you asked! Right now, there are two major experimental approaches for fusion being studied: magnetic confinement and inertial confinement.

In magnetic confinement fusion, the electrical conductivity of deuterium-tritium plasma is used to contain it within magnetic fields at a high pressure and heated to fusion temperature. Because the particles need to be repelled from the walls of a reactor (otherwise contact will dissipate their heat and slow them down), the most effective magnetic configuration is toroidal wherein the magnetic field is curved around and forms a closed loop. There are several different types of toroidal confinement systems but the most important are tokamaks and stellarators (reversed-field pinch devices would be next; however, plasma confinement in the best RFP is only about 1% as good as in the best tokamaks, owing largely to the fact that existing RFPs are very small).

Tokamak

Stellarator

In inertial confinement fusion, which is a newer line of fusion research, laser or ion beams are focused extremely precisely on a target - a pellet of deuterium-tritium fuel only a few millimeters in diameter. When the outer layer of the material is heated, it creates an outward explosion that generates an implosion that in turn compresses and heats the inner layers of material and results in conditions in which fusion can occur. The core of the fuel may be compressed to 1,000 times its liquid density and the energy released heats the surrounding fuel that may also undergo fusion, leading to a chain reaction (this is referred to as ignition) as the reaction spreads outward through the fuel. 

Large scale attempts at inertial confinement fusion include the Shiva laser built by Lawrence Livermore National Lab, followed by the Nova laser, the 24 beam OMEGA laser and the Novette Laser, which all paved the way for the National Ignition Facility in Livermore, California.

Question:

Theoretically, what conditions would be necessary to sustain artificial nuclear fusion as an energy source?

Asked by anonymous

Answer:

Currently, the problem with nuclear fusion is that there isn’t yet a chain-reaction mechanism that could create a self-sustaining fusion reaction. This is why fusion reactions either produce uncontrollably large amounts of energy with a large-scale trigger, as in fusion bombs, or– as of now, at least– produce less energy than the trigger itself on a controlled scale. Research is still ongoing to find ways to achieve “breakeven”, the point at which fusion produces more energy than is consumed in igniting the fusion fuel in the first place.

Currently, controlled fusion research has two major branches: inertial confinement and magnetic confinement. Magnetic confinement uses magnetic fields to confine the hot fusion fuel in plasma formInertial confinement attempts to create fusion using a radioactive pellet, known as a target, that undergoes a reaction when hit with a laser. The major issue with both is being able to deliver the trigger energy to the fuel with enough accuracy and power to start and sustain fusion without creating instabilities that reduce the efficiency of fusion.

Answered by Emma B., Expert Leader.

Edited by Peggy K.