Nuclear energy has the potential to be weapons and
radioactive waste free, but that depends on what process you use. Your
choices are:
The ideal choice is aneutronic fusion. (A new...what?) "A" means "without"; "a-neutronic" means without neutrons as a byproduct. What is it about neutrons that makes such a difference? (And what's the catch?)
The ideal choice is aneutronic fusion. (A new...what?) "A" means "without"; "a-neutronic" means without neutrons as a byproduct. What is it about neutrons that makes such a difference? (And what's the catch?)
Fission and the trouble with Neutrons
Nuclear FISSION
When most people think of nuclear energy, they think of fission. With fission, a neutron splits a large atom into smaller ones, releasing more neutrons for a chain reaction. Control rods are required to soak up extra neutrons to avoid meltdown.
When most people think of nuclear energy, they think of fission. With fission, a neutron splits a large atom into smaller ones, releasing more neutrons for a chain reaction. Control rods are required to soak up extra neutrons to avoid meltdown.
Neutrons make things Radioactive.:
The fuel is radioactive, and the byproducts are radioactive. Neutrons
change the nature of things they slam into, making them radioactive.
The Result: Steam
The Neutrons in fission generate heat. Heat turns water into steam, to spin a turbine. This generates electricity. So, nuclear power is fuel for an 18th century steam technology.
The Neutrons in fission generate heat. Heat turns water into steam, to spin a turbine. This generates electricity. So, nuclear power is fuel for an 18th century steam technology.
Conventional (neutronic) fusion - DT
Nuclear FUSION has the potential to generate
power without the radioactive waste of nuclear fission, but that depends
on which atoms you decide to fuse. Conventional fusion approaches work
with deuterium and tritium, while aneutronic fusion works with other fuels. When deuterium and tritium fuse, they yield an alpha particle and a neutron.
Tritium
Tritium is hydrogen with two extra neutrons. It doesn't occur in nature. It's rare, super expensive, radioactive and has proliferation dangers. A key challenge of neutronic fusion is how to breed tritium.
Tritium is hydrogen with two extra neutrons. It doesn't occur in nature. It's rare, super expensive, radioactive and has proliferation dangers. A key challenge of neutronic fusion is how to breed tritium.
Neutronic Fusion
When deuterium nuclei fuse with tritium, they form an alpha particle (harmless Helium ion) and a neutron. Yes, that pesky neutron. The radioactive waste from fusion is less than fission, and shorter lived. But it is not eliminated.
When deuterium nuclei fuse with tritium, they form an alpha particle (harmless Helium ion) and a neutron. Yes, that pesky neutron. The radioactive waste from fusion is less than fission, and shorter lived. But it is not eliminated.
Energy Output
The neutron generates heat which needs to be captured somehow and will likely heat water and produce steam to spin a turbine... Here again we have Space age technology to power 18th century steam engine.
The neutron generates heat which needs to be captured somehow and will likely heat water and produce steam to spin a turbine... Here again we have Space age technology to power 18th century steam engine.
Aneutronic Fusion: the best is yet to come.
| 1H + 2 6Li → |
| 1H + 7Li → |
| 3He + 3He → |
| 1H + 11B → |
Aneutronic Candidates
Aneutronic fusion is fusion that does not produce neutrons as a product of the reaction.
There are several element combinations that can be used in aneutronic fusion. We'll look at the most likely one here: 1H + 11B aka pB11.
Note: H stands for hydrogen. A hydrogen nucleus is a single proton, hence "p" for proton also refers to hydrogen.
Aneutronic fusion is fusion that does not produce neutrons as a product of the reaction.
There are several element combinations that can be used in aneutronic fusion. We'll look at the most likely one here: 1H + 11B aka pB11.
Note: H stands for hydrogen. A hydrogen nucleus is a single proton, hence "p" for proton also refers to hydrogen.
Proton Boron (pB11)
When a boron-11 nucleus fuses with a hydrogen nucleus - the result is three helium nuclei (aka "alpha particles") and energy, but no radioactive waste.
When a boron-11 nucleus fuses with a hydrogen nucleus - the result is three helium nuclei (aka "alpha particles") and energy, but no radioactive waste.
Electricity Directly
But wait! If there are no neutrons produced, where do you get heat for the steam engine?
You don't. The Helium ions coming out are positively charged - it's electricity directly.
This is a space age fuel that finally cuts the umbilical cord of steam.
But wait! If there are no neutrons produced, where do you get heat for the steam engine?
You don't. The Helium ions coming out are positively charged - it's electricity directly.
This is a space age fuel that finally cuts the umbilical cord of steam.
Awesome! Where can I get my Aneutronic Fusion?
There's a catch, of course. Aneutronic fusion is
difficult to achieve. It requires an order of magnitude higher
temperatures than neutronic fusion (it's very HOT fusion). Humanity
hasn't figured out how to harness it yet.
It's an awesome, burning energy challenge. A lot of people think it can't be done. They don't have much confidence in their fellow human beings. The physics - daunting. Perhaps even more difficult - the finances, the collective action problem to get adequate resources to mount a thorough investigation of this challenge.
Luckily, there are some scientists boldly exploring the frontiers of aneutronic fusion, including the crew working on the LPP Experiment. These projects need our support, they need our encouragement and they need our conscious commitment.
There
are many reasons to pursue aneutronic fusion. You may be in it for the
energy, or for saving the world, or for getting rid of nuclear weapons.
On top of those practical reasons, this is about downloading the power
of the stars, stealing fire from the gods, redeeming nuclear power.
It's about showing the universe what we're capable of.
It's an awesome, burning energy challenge. A lot of people think it can't be done. They don't have much confidence in their fellow human beings. The physics - daunting. Perhaps even more difficult - the finances, the collective action problem to get adequate resources to mount a thorough investigation of this challenge.
Luckily, there are some scientists boldly exploring the frontiers of aneutronic fusion, including the crew working on the LPP Experiment. These projects need our support, they need our encouragement and they need our conscious commitment.
There
are many reasons to pursue aneutronic fusion. You may be in it for the
energy, or for saving the world, or for getting rid of nuclear weapons.
On top of those practical reasons, this is about downloading the power
of the stars, stealing fire from the gods, redeeming nuclear power.
It's about showing the universe what we're capable of. 
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