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How Close Are We, Really, To Nuclear Fusion?
StartsWithABang writes: The ultimate dream when it comes to clean, green, safe, abundant energy is nuclear fusion. The same process that powers the core of the Sun could also power everything on Earth millions of times over, if only we could figure out how to reach that breakeven point. Right now, we have three different candidates for doing so: inertial confinement, magnetic confinement, and magnetized target fusion. Recent advances have all three looking promising in various ways, making one wonder why we don't spend more resources towards achieving the holy grail of energy.
This graph explains very clearly how far away we are, and why it is taking so long. The reality is, with all the cheap coal (and natural gas), it's just not a priority. Besides, environmentalists hate nuclear so it's not a political winner to fund it. This story is good, too.
"First they came for the slanderers and i said nothing."
Natural reserves of tritium do not exist on Earth, but it can be made easily from lithium. In fact, tritium can be made using the high-energy neutron released from the fusion reaction and offers the possibility of making tritium in situ in a fusion reactor. The neutron is absorbed by the lithium to produce tritium.
"First they came for the slanderers and i said nothing."
First of all, a proton is an hydrogen nucleus. Also, matter and anti-matter aren't the same thing at all. The fundamental particles with positive and negative charges with stable arrangements making atoms are called quarks. E.g.: a proton is made of 2 up quarks (charge +2/3) and one down quark (charge -1/3) for a total of one atomic mass and 1 elementary charge. An anti-proton is made of 2 anti-up quarks (-2/3) and one anti-down quark (1/3) for a total of one atomic mass and -1 elementary charge. Baryons are made of quarks and anti-baryons are made of anti-quarks, not the same thing, not the same thing.
No, they don't. Protons and electrons squeeze together quite a lot in white dwarfs and pulsars, both types of objects being extremely stable, so we know for a fact that it doesn't happen. Again nothing surprising taking into account that protons and electrons aren't anti-particles of one another.
The only -current- viable source of tritium is fission. However fusion can produce its own tritium in breeder blankets. This is one of the concepts that will be researched in ITER: https://www.iter.org/mach/trit...
So the last part of your post "but it's not a viable power source unless the need for tritum is eliminated" is just wrong.
There are also proposals to put a large solar array several square kilometers in area in the Sahara Desert that could generate power for the entire planet. Then there's the Gobi Desert where it could also be done, the Mojave already has some solar concentrator sites with more planned (if they can fix the bird frying problem). So, there are ways for us to generate the electricity that we will need for a long time from renewable sources. I don't discard or disparage nuclear fusion research because it is also important going forward, but we do have other practical ways of generating electricity from natural phenomena, wind and tidal being two others that are coming along a lot faster than better fission and currently non-existent fusion reactors.
It's there, but we have to put an absurd amount of relatively rare resources into photovoltaic cells to make *use* of that energy. Otherwise, it performs a very useful function in that it gives us this thing called heat, so we don't all freeze to death and die (and so we can have an ecosystem of animals and plants that we don't have to keep in climate-controlled environments that also won't freeze and die).
No, I'm sorry, but the primary purpose of the sun is to give us energy in the form of light for plants and heat for everything else (including plants). With current technology we can't make use of the sun well enough to meet more than a fraction of our energy demands.
Now, if we had a steadily shrinking worldwide population, we might be able to do it, since we'd have more and more surplus energy every year without even doing anything -- which means if we continue to increase production of renewables like solar and wind year over year, and population decreases, it's mathematically certain that at a point not too far in the future the two will intersect and we can shut down the last coal/diesel/natural gas/nuclear plants.
But unless you can find a way to cause the population to shrink worldwide year over year in a controlled, preferably non-violent manner, I don't see a way that renewables will ever become dominant. It's not economically feasible. We can't divert enough resources to making solar panels and wind farms to meet energy demands, even if we cut worldwide energy demands per capita by 25% immediately and cut the energy use of the most energy-intensive top 5% by 75%. Even with such unrealistic and aggressive cuts in per capita consumption, an exponentially increasing population will ultimately make the exercise pointless.
We have several cheap battery technologies. Molten salt (big vat of hot liquid, heated by incoming power to charge, steam engine taking off heat to provide electricity), and hydroelectric (big reservoir up high in the mountains, recharge by pumping water into it, water turned generators to draw power off).