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@bajax @tard @p @fluffy I think solid state batteries have much promise but there is the issue of adequate ion mobility in a solid material. That said what I've read about these batteries is more rumor than actual test data so I haven't a lot of concrete data upon which to base an opinion but I will note that most commercial solid state batteries aren't completely solid and are some sort of hybrid designs because of the ion mobility in solids issue. That said, I am hoping something positive develops, I personally would love an electric car as a primary city driver since the majority of my trips are under 100 miles in a day, but lithium fires dissuades me. But as grid storage I don't think conventional batteries will ever scale sufficiently. Redox flow batteries I believe are about the only chemical battery technology with enough scalability to be useful at grid levels, but thus far they rely on vanadium and vanadium although about as abundant in the Earth's crust as copper, rarely exists in concentrated form and thus is expensive to extract and most comes from China, Russia, South Africa.

@shironeko @cjd @bajax @tard @p @fluffy You do not understand the issue at all.

We depend upon modern agriculture that involves a lot of large machines burning a lot of diesel to grow enough food to sustain a world population of 8 billion.

Subsistence farming with oxen and plow simply will not yield enough product from the land to sustain this population.

We depend upon diesel fuel to transport that food by truck, and in the US also by train.

The nature of extractive technology is to start with the most readily available and higher quality ores, use them, and then work towards the lesser quality harder to get at ores.

At some point the amount of energy in exceeds the amount of energy returned and at that point economic viability is zero. As we approach that point fuel, and thus food, becomes increasingly expensive and as it does people start to start from low economic strata on up.

We are at the point where we have exhausted all surface reservoirs and most deep reservoirs, we are now largely dependent upon tar sands and shale oil. Neither of these is rich in the distillates that are necessary to run our farm equipment and both are not far from exhaustion.

When they exhaust there is really nothing left to fall back on except nuclear energy and syn fuels, wood gas won't run your tractor.

@cjd @p @fluffy @bajax @tard The big expense of nuclear plants today resolves around things like the need for a containment building, not required for a molten salt reactor, plumbing has to withstand 200-300 atmosphere, emergency water dump systems for when the plumbing fails and all the water flashes to steam, emergency backup generators that have to keep cooling going if commercial AC fails.

Molten salt reactors by contrast don't require containment domes because they have no explosive failure modes, don't require active cooling in the event of a failure because first off they are self-limiting because the salt expands as it heats and reduces reaction rates, and that by itself is generally enough, but if it gets too hot anyway, a freeze plug melts and drains the molten fuel into a much larger tank that spreads it out too much for the reaction to continue and because fission products are continuously removed, there is no residual heat from fission products.

There is no water so no hydrogen explosions.

The only real failure mode is get a leak in the plumbing, and the liquid fuel/salt mixture leaks out and solidifies on the floor. And because fission products are continuously removed it is not so hot that it can't be handled so is scooped up thrown back in the reactor, plumbing fixed and life goes on.

These inherent safety features make the insane active features necessary in boiling water reactors unnecessary and with them their expense.

@cjd @p @fluffy They are two different things but they are best together. The reason, U235, the fissionable isotope of Uranium is only .7% of Uranium, and Thorium is 3-4x more plentiful than Uranium, so energy available if you breed thorium is 4000x+ that available from U235, add U238 and make that 5000 times, add all the actinide waste from existing nuclear reactors and even more.

And it is the actinide waste that in my view is the greatest reason we should build fast spectrum breeders, we can power civilization for 1000 years on the existing nuclear waste because 95+% of the fuels original energy potential is still present in the waste. And doing so converts ALL of the actinides into short-lived fission products with the sole exception of technetium which is the one fission product with a longer than 30 year half-life. Even so this reduced the long term waste to only one isotope, much easier to keep isolated and much lower in total bulk.

There is the issue of neutron economy which is less in a fast spectrum reactor,
but there is a solution that is between thermal and fast spectrum that has all of
the advantages of both and that is to use a beryllium or lead neutron multiplier, this takes one fast neutron and spits out two slower but still faster than thermal and in a range readily usable by even numbered actinides. (the odd numbered actinides can be fissioned by thermal neutrons so they are not difficult).

The other reason I don't favor thermal designs is the moderator is either water or graphite and then you have either hydrogen explosion and corrosion, and water is not really compatible with high temperature salts so that's no good, or graphite, and graphite is flammable and leads to Chernobyl type fire instances. Particularly this happens because graphite captures some neutrons and becomes contaminated with time and occasionally has to be heated to high temperatures to be purged, and this presents a fire hazard if oxygen somehow leaks in.
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