(Missed Edit)
Thanks all, for your responses!
They pretty much do have the same composition, only on Earth most of the heavy elements sank to the core, especially precious metals which have a tendency to be attracted to iron; most of what we mine actually came from asteroids.
Even without asteroid mining, the rare-earth-metal problem will become less severe with time. Part of the reason they’re so hard to come by is that, up to now, nobody bothered to mine them, because they didn’t have much use. Now that they do have a mass-market use, folks are going to dig more mines for them.
Weren’t the first capacitors called batteries?
No, Leyden jars.
I do not agree with the premise. NG is not at all dead. Yes it does produce more green house gases during production due to leaks - but that can be easily fixed once regulations are passed. It is far cleaner than coal since it has very little sulfur, no mercury or the myriad heavy metals. It is far more efficient (and thus less CO2 release) to run the car directly off the natural gas than use the natural gas to produce power, lose efficiency in power generation, transmission, battery efficiency than to run the car off Natural gas itself. The biggest advantage maybe in refueling the car since batteries take a long time to charge while natural gas can be “filled up” in minutes.
The term “battery” just refers to having a bunch of elements in series to increase their total voltage-- This can be done with capacitors or chemical cells alike. And it’s kind of a misnomer now, when most “batteries” are single cells.
Not “clouds”?
i guess “battery” just means “a bunch.”
I live near Battery Park in NYC (old defensive line) and have amassed a batterie d’cuisine.
Is this true? I thought well to wheel was better by the electric route - even with generation, transmission and storage, power plants are that much more efficient than individual engines.
Yeah, I thought one of the newer NG plants could be up to 75% or more efficient, whereas a car engine tops out around 25%. I’ll see if I can’t find the cites later…
There’s still the production issue; if my calculations are correct (based on current NG as percentage of energy use), we’d have to increase production by 4-5 times over what we have now, which seems unlikely, even with the new shale gas techniques; I’d expect a significant increase in the cost of natural gas as a result, making it less attractive than electric. Also, electricity can be generated from many different energy sources, including nuclear (which is pretty much electric-only) and renewables (which again are mainly for electricity production, as used on a commercial scale). There is also the efficiency issue, as mentioned in the last few posts, with burning gas in an onboard engine vs. electric NG generators (is a NG engine much more efficient than a gasoline/diesel engine, and NG power plants can be 2-3 times more efficient than the latter).
To directly answer the OP, no, battery capacity has not reached its maximum. There’s plenty of research and development being done and capacities are expected to rise. There is no one path towards greater capacity, many technologies/techniques are being examined and exploited.
This is true, but the real problem with rare earth elements isn’t locating and mining them, but separating and refining them for practical use, which requires the use of highly caustic solvents and a lot of water. This is why nearly all rare earth production (upwards of 97%) is now done in the Peoples Republic of China, which is one of the few nations that has both industrial capability and the political willingness to accept the environmental pollution that goes along with this processing. (The same used to be true of India, Australia, and several other countries outside of North America and Europe–hence why Union Carbide and many other chemical processing companies maintained large facilities there–but those countries have tightened up environmental laws following releases and accidents, most notably the 1984 Bhopal disaster.)
What mining rare earth materials from extraterrestrial sources would give you is the ability to separate, refine, and process these materials in space where there is no environmental impact of concern. However, the cost of developing the required propulsion capability, manufacturing systems, and other infrastructure to support this is would be huge; likely measured in the trillions of US dollars, and as such, there are large technical and fiscal hurdles before this will be practical. It is likely that such capability will be incidental to some other effort such as meteor defense, establishment of permanent orbiting habitats, or other effort that will develop sufficient infrastructure to support mining and exploitation of space resources.
As for battery capacity, the potential chemical energy density of electrolytes that could be used in a battery is a couple orders of magnitude more than current battery energy density. So while we will never achieve the maximum density of chemical electrolytes (because a battery, by definition has a non-energetic substrate and/or container) there is definitely room for improvement. However, fuel cells (which oxidize their constituents rather than just transfer ions) already offer considerably more energy throughput, and at least for vehicle-size applications, have a higher energy density and watt-hour capacity. They are, of course, somewhat more hazardous in that they contain highly reactive “wet” chemicals versus mild acids or dry constituents like batteries.
The other possibility, albeit one that is not feasible in the foreseeable future, are nuclear isomer batteries, which store energy in metastable isotopes of some elements and release them due to stimulated decay. The energy density of this medium would be orders of magnitude more than could be realized by chemical electrolytes. Such isomers have been suggested as the lasing medium for high energy x-ray/gamma ray lasers, but as far as I know have never been realized in a workable laser, and certainly not in a battery.
Stranger
Mining asteroids:
I’m not a scientist or economist, but I think this highlights a few of the huge blind spots in our current financial and governmental systems. Everything we have now is geared to exploit scarce resources and protect territory.
The problem with mining asteroids is that by doing so you’d crash the market in those materials overnight. That’s an even bigger problem than the huge up-front investment you’d need to make to develop the technology to go to a more distant orbit than Mars, grab something massive, and bring it back to near-Earth orbit.
The only way I know of to solve that financial problem is essentially by deliberately sitting on the supply and dribbling it out in small enough amounts to keep the markets from hugely discounting the commodity price. But even that won’t completely control the system because investors know that the supplies are still there and will act accordingly, so this won’t work all that well for long.
Then there’re the safety issues. Even if you’ve licked the problem of matching trajectories well enough to create a stable orbit for a massy chunk of something, your system also has to be able to handle propulsion failures in the main drives, or have a backup that’s capable of intercepting a moving massive object and move it into a safe orbit before it enters the atmosphere and you have no hope of keeping it from de-orbiting.
You’ve still got the issue of trust. Any organization that has mass orbiting the Earth is an organization that can literally rain fire down from the skies on any territory anywhere with not a whole lot of lead-time. A decent sized meteor moving at just under orbital speeds can impact a nice neighborhood with the equivalent force of a small nuclear weapon. Would you trust any corporation with that kind of power? Would you trust any government with it either?
This is a non-issue. It would be quite easy to plan your trajectories in such a way that a propulsion failure at any point would just send the rock off into empty space. A planet is a really small target, after all.
Now, this is more legitimate. But then again, it’s a bit late to ask if we’d trust any government with that kind of power, because we already do. Targeted asteroids aren’t the only weapons that can have an impact equivalent to a nuke.
This is absolutely true, and one of the primary reasons why developing asteroid mining infrastructure to support terrestrial markets isn’t really a plausible market. This isn’t to say that there wouldn’t be other motivations–such as non-profitable extraction of resources such as copper that may be depleted–but it is far more likely that conservation or substitution will be more viable. Exploitation of space resources really goes hand in hand with the development of orbiting habitats, and the path to achieving the fiscal, technical, and logistical thresholds for achieving that capability are still unclear.
Chronos has correctly addressed the safety and security issues, but to expand on the latter, once some party enjoys the gravitational high ground of orbital space, there is little effective protection on the planet’s surface. That is an innate limitation of planets; they’re large, exposed, and can’t dodge an incoming hazard. But they’re pretty and and have interesting weather.
Stranger
Yes, not hitting the planet is way easier than hitting it, but anything that is going to get it into a stable orbit has a non-zero chance of failure, and that failure could push a rock into a rapidly decaying orbit that could be hard to recover from.
No, they aren’t the only weapons capable of that kind of destruction, but a missile launch is a shitload easier to detect than one rock among hundreds either in transit or in orbit if large-scale mining were implemented. Incoming materials on an impact orbit would be virtually indistinguishable from a tangential orbit until rather late in the game. Things already in orbit would need to be actively tracked in order to detect destructive changes in orbit. And in either case, preventive measures would be even more difficult than present anti-missile ones that are already in place.
The only “rapidly decaying orbits” are those in the lower mesosphere. Objects in the thermosphere or above decay very slowly and observably. (The International Space Station orbits at roughly the middle of the thermosphere, and requires minor boosts to higher orbit only every several months.) It is actually surprisingly difficult (in both control and energy required) to deliberately cause an object in an elliptical orbit to fall into an intersecting orbit, especially above Low Earth Orbit (LEO), and a mistake is far more likely to kick the object into a higher or more elliptical trajectory. Lunar return trajectories in Apollo were on the ragged edge of “skipping” off of the atmosphere. The Shuttle re-entered from LEO by using the Orbital Maneuvering System to get low enough that it was further slowed by drag.
However, bear in mind that rather than moving an entire asteroid into Earth orbit, it would be much more practical to move mining and production facilities to the trajectory of the object in question, reduce and refine it in situ, and then ship the usable product to Earth, thus not wasting energy and propellant moving around waste mass that then will either pollute Earth orbit or have to be removed. So the more likely scenario is smaller, more maneuverable payloads that represent a negligible threat to anyone on the surface of the Earth.
Stranger
What about these guys? http://www.planetaryresources.com/