Why give up on fusion?

The U.S. government has pulled funding on fusion research. Why do this considering the tremendous benefits of such technology?

 

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Their energy policy revolves around oil.

 

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Are any other countries taking on the research?

 

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Not really. the U.S. government has funded research on civilian fusion use for nearly five decades and has spent multiples more than the rest of the world combined. There are no practical results to date.

 

I believe the French are about to complete a fusion reactor.

 

You mean the French are about to complete a reactor so they can study fusion - not actually produce more energy than they put in?

 

ITER should produce more power than it consumes. This is expressed in the value of Q, which represents the amount of thermal energy that is generated by the fusion reactions, divided by the amount of external heating. A value of Q smaller than 1 means that more power is needed to heat the plasma than is generated by fusion. JET, presently the largest tokamak in the world, has reached Q=0.65, near the point of "break even" (Q=1). ITER has to be able to produce Q=10, or Q larger then 5 when pulses are stretched towards a steady state. This is done so that, in the "burning plasma", most of the plasma heating comes from the fusion reactions themselves.

According to their website, the US is involved with this project as well.
http://www.iter.org/index.htm

 

Moon Juice

http://www.space.com/scienceastronomy/helium3_000630.html

psik

 

I guess they gotta pay for the war in Iraq somehow

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They havent pulled out of ITER have they?

 

Yeah, people love to bring up helium-3 on the moon. There's the slight problem that it's much easier to fuse deuterium and tritium or even deuterium and deuterium than to fuse helium-3. And no one has yet been able to actually make a working deuterium/tritium reactor yet. Also, the supply of deuterium in the earth's ocean's is basically limitless. So, by the time we have the technology to build a helium-3 fusion reactor we will probably also have the technology to build deuterium reactors that have unlimited fuel right here on Earth. For some reason these "let's go to the moon to mine helium!" articles always forget to mention that.

There are some big advantages for using helium-3 in spacecraft propulsion, since it has a higher energy density than deuterium/tritium or deuterium/deuterium. Also the reactor can be lighter, since it would require less shielding. So yeah, if you want to build a fusion-powered interstellar space ship, helium-3 is a really good choice. But if you want to build big power plants to provide energy here on Earth, it's probably never going to be able to seriously compete with deuterium and tritium.

 

The only snag with ITER is that it will take many years to get anywhere. The last time line I saw ended in something like the 2020's.

 

THis is news to me, and apparently to the fusion research budget planners in the US Department of Energy.

 

Probably because the efficiency of other sources of energy (wind, solar, biomass, etc) are becoming more promising both economically and politically.

 

After 50 years of research and over 5 trillion dollars spent worldwide it seems that fusion can't be achieved as yrt. So do you think it is worthwile to pour more trillions of dollars into a project that shows NO signs of working or try to invest money into other forms of more environmentally friendly energy sources.

 

Where did you get the 5 trillion dollar figure? That's impossible to believe.

 

I'm thinking of all of the countries that have been trying to develop fusion for the last 50 years and I'd think that figure worldwide is close to the amount all countries put together have spent. Some countries like Russia won't tell us how much they spent but is is more than America I'd bet.

 

Yeah, but 5 trillion is so enormous a sum, I can't believe that's anywhere close to the truth.

 

Well what would you put the figure at. Also with all that money spent we reall have nothing to show for it.

 

How do we know nuclear fusion even exists?