The running joke is that we are always 20 years away from viable commercial fusion power, and there is quite a bit of truth to that. The estimates have always been saying so since the 60s. But trust me, physicists have been making progress on fusion power: learning how the plasma interacts (in a tokamak reactor) and how to control it, and how to blast the fuel with massive lasers with new and constantly developing optics.
So in honor of Rachel's Geek Week I give you the status on Fusion Power! The savior of our energy problems!
Fusion power is technically nuclear power. It literally smashes atoms together at high temps and pressures and creates energy just like the sun. But unlike fission which splits heavy atoms and creates radioactive waste, the method that fusion uses takes deuterium and tritum (kinda like hydrogen but with extra neutrons) and smashes them together to create helium as a waste product. Helium which can be used by industry instead of mining for it.
Where do we get the deuterium and tritium? Water.
Deuterium is found in plain old water. 1 in 7,000 atoms of hydrogen are Deuterium. This can be extracted pretty easily. Tritium is rarer, but fear not. If you blast Deuterium with neutrons you can create Tritium! (Neutrons which are produced during both nuclear fusion and fission)
So now when you have your deuterium and tritium (a total of 2 protons and 3 neutrons) you blast them together a high heats and pressures and produce Helium (2 protons and 2 neutrons) and 1 neutron plus a whole lot of energy.
So that is fusion power in a nutshell. Now where do we stand?
Well we (alright I don't know a ton about laser based fusion so I won't focus on that here...perhaps somebody else) have all seen pictures of these cool machines that are supposed to solve the energy crisis.
This is called a tokamak. Its a toroid shaped container that magnetically keeps a plasma hot as the sun contained in a vacuum while we smash together our precious deuterium and tritium.
Currently the biggest one is at MIT and there is also JET in Europe. Both of these have experimented with "break even" conditions which is where the heat out is equal to the heat in.
So why arn't these generating all our power requirements?
They were not designed for that. All of the tokamaks in operation right now were built not to generate energy but to study how a plasma works, how to control it. That is changing right now though!
ITER to the rescue!
ITER is a tokamak reactor currently under construction in the south of France...and guess what it is specifically designed to produce 10x more energy then input into it!!!!
Here is a picture of this wonderful machine.
Can you see the human drawn in there to give scale? This thing is huge!
But is it a power plant? No...sorry. Again this reactor is another study.
For a commercially viable power plant we need to achieve somewhere between 15x and 30x energy out to energy in. But ITER is definitely on the right track as this will be the first time we will try to extract energy out of a fusion reaction...its just not commercially viable at this stage.
So in summary we're making progress...it just might be a little while. So in the meantime lets keep up the effort on the solar and wind!
Links for further reading:
European Fusion Development Agreement: A conceptual Study of Commercial Fusion Power Plants
European Fusion Development Agreement: The current status of fusion research
ITER and beyond