For the past 70 years, scientists have been working towards unlocking viable nuclear fusion technology. But what is the holdup? Clearly the science “works” because stars exist. Why can’t modern technology generate a stable, commercially viable fusion reaction? From my perspective, there are likely only three scenarios impeding a nuclear fusion industry.
Is it a matter of materials engineering technology, where we simply cannot fashion the machinery/ equipment capable of handing the intense temperatures associated with fusion?
Do we not have the right mixture of fuels, precursors, and “catalysts” to trigger a stable reaction?
Or does the tech actually work fine and flawlessly, but it is just extremely cost prohibitive to set up a fusion reactor when a coal/oil/gas power plant already exists and investing capital refuses to fund fusion projects?
In: Engineering
Fusion happens when two small atoms (like hydrogen) are pushed _so close_ together that nuclear attractive forces take over and they fuse into a larger element, releasing some energy in the process.
For a fusion reaction to naturally become self-sustaining, it needs to be _massive_. The size of a star. At that size, the gravity of the star is enough to pull the hydrogen atoms close enough together to get fusion to occur.
Naturally, we can’t build something the size of a star on Earth. So for us to get the atoms close enough together to undergo fusion, we have to use incredibly strong magnetic fields or powerful lasers. That takes a ton of energy – so much so that what we get _out_ of the reaction is less than the energy it takes to make it happen.
Every year we get a little bit closer – we figure out how to generate the fields using less energy and we figure out how to extract more energy from the reaction. We just haven’t gotten to the point yet where the net production is positive.
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