They are good for infrequently used track and places where overhead wires would be in the way, like that very Tesla employee shuttle on it's own track and container ports.
It's not the best way to go for mainline track and not suitable for long distance high speed trains.
Ireland is going to use a particularly unusual one for the Dublin-Belfast intercity route. It will have batteries, _and_ diesel generators, _and_ will run off overhead lines, in two voltages. The context is that parts of the line will take a while to electrify; it will initially run on overhead, battery, and diesel, then just overhead and battery as the lines are built out, and then hopefully finally just overhead.
The words sum up to "don't go straight unless you have business being there" but still, it really sums up the approach to signaling. Nobody in the whole command chain sat and thought "that might be a tiny bit difficult to parse".
I mostly read those signs as “don't go there unless you already know you can” which as a “tourist” I just assume can't (unless I'm a local, and figure it out).
What I've recently found troubling is the places that use similar signs for emissions controls. With a rental you usually have a recent enough car that you can ignore those.
Being able to distinguish between “low emissions zone, but any car from this decade can go in” and “local traffic only, you need to live in this neighborhood to enter” in a foreign language, bit me a couple of times while traveling.
Huh, here in Germany we have street signs (mostly of a "you are the priority road" 45° rotated square yellow-on-white "sunny side up egg" sign and the "you are not the priority road" down-pointing white-on-red triangle; for 3-way if the priority road isn't the straight road or the concept of straight is ambiguous, there's a supplemental sign depicting the path of the priority road) permanently on traffic lights; it's also common enough for non-major roads to have the lights turned off at night so drivers tend to be familiar with falling back to the signs when the lights are off.
In absence of priority roads there is also the "right before left" rule which means that the car coming from the right if they would conflict in time is the car that has priority.
It's also always illegal to enter an intersection if you can't immediately clear it; that seems to work better when there are no green traffic lights to suggest an explicit allowance to drive, though.
Sure, but we're pretty far from Germany over here.
In the States (or at least, every US state that I'm familiar with -- each one is free to make their own traffic rules, similar to how each EU member state also has their own regulatory freedoms), a dark/disabled/non-working traffic light is to be treated as stop sign.
For all drivers, in all directions of travel: It functionally becomes a stop sign.
That doesn't mean that it is the best way, nor does it mean that it is the worst way. It simply is the way that it is.
How does "you can only piss with the cock you've got" translate to German slang?
You don't use ponds, you run the desalination to as strong as practical and follow up with either electrolysis or distillation of the brine.
But once summer electricity becomes cheap enough due to solar production increasing to handle winter heating loads with the (worse) winter sun, we can afford a lot of electrowinning of "ore" which can be pretty much sea salt or generic rock at that point.
Form Energy is working on grid scale iron air batteries which use the same chemistry as would be used for (excess/spare) solar powered iron ore to iron metal refining.
AFAIK the coal powered traditional iron refining ovens are the largest individual machines humanity operates. (Because if you try to compare to large (ore/oil) ships, it's not very fair to count their passive cargo volume; and if comparing to offshore oil rigs, and including their ancillary appliances and crew berthing, you'd have to include a lot of surrounding infrastructure to the blast furnace itself.)
It will take coal becoming expensive for it's CO2 before we really stop coal fired iron blast furnaces. And before then it's hard to compete even at zero cost electricity when accounting for the duty cycle limitations of only taking curtailed summer peaks.
Not that it's super relevant to this discussion, but I think the largest individual machines operated would probably have to go to high energy particle accelerators like the LHC at CERN or those operated by Fermi Lab.
Billions of dollars in cost, run 24/7 with virtually no downtime during regular operations, in underground tunnels with circumferences in the tens of miles, and all throughout is actively-coordinated super conductors and beam collimation in a high-vacuum tube attached to absurdly complex, ultra-sensitive, massively-scaled instrumentation (not to mention the whole on-site data processing and storage facilities). Certainly open to bring convinced otherwise, but aside from ISS in pure cost, so far it's my understanding that those are the pinnacle of large-scale machines.
Do you know how much magnesium you find with silicon and iron as olivine?
It's just the silicon that we haven't yet tamed for large scale mechanical usage that makes them uneconomical to electrolyze.
2021 total world energy production of approximately 172 PWh would require 27.5 billion metric tons of lithium metal at typical 0.16g/Wh of a modern LFP cell; meanwhile, we have approximately 230 billion metric tons of lithium for taking (e.g. as part of desalination plants producing many other elements at the same time from the pre-consecrated brine) from the oceans.
Note that we require only a fraction of a year's worth of energy to be stored, I think less than 5% if we accept energy intensive industry in high latitude to take winter breaks, or even more with further tactics like higher overproduction or larger interconnected grid areas.
And that's all without even the sodium batteries that do seem to be viable already.
Think of those numbers as one kind of in extreme case argument.
Another reality is that most of the global grid scale energy usage is not transport via mobile batteries that benefits most from high energy density lithium batteries that pack maximal energy from least weight.
Battery farms don't move, they can use other battery chemistries that are cheaper in resources and weigh a lot more per energy unit than lithium while still powering cities, smelters, processing plants, etc.
As for desalination in general, yes, there will be a lot more of that in coming years, fresh potable water supplies are stretched from a global PoV.
Grid scale LFP with once daily cycling lasts 30 years before the cells are degraded enough to think about recycling.
And those are very low maintenance over that time.
You're probably mostly going to swap voltage regulators and their fans, perhaps bypass the occasional bad cell by turning the current to zero, unscrewing the links from the adjacent cells to the bad cell, and screwing in a fresh link with the connect length to bridge across.
Also: From what I understand the LFP battery degradation is essentially corrosion that is removed by recycling and you can retrieve 99% of the essential LFP elements and make it into a new battery. So economically we only need to extract the LFP related materials for each human user almost once, instead of oil over and over again.
If you're in the US just look up the small claims process local near you, and do it.
The fee is small and you'll learn how it works, and that's worst case.
It's not the best way to go for mainline track and not suitable for long distance high speed trains.
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