The reports I've seen say it'll probably be similar to the Jupiter Direct proposal that a number of NASA engineers had been proposing as an alternative to the problem-plagued Ares rocket development. So still based on shuttle hardware, but probably a better design.
You really have no sense of where government money goes, do you? TANF (federally-funded welfare) is $16.5B. By contrast, the latest Pentagon budget request is $768.2B.
Welfare is a really tiny portion of our total expenses.
1) Modern automotive-style li-ion battery lifespans are similar to transmission lifespans or other vehicle component lifespans. Fuel cells, on the other hand, have about half the lifespan of said batteries. 2) It's not that li-ion batteries are difficult to recycle; it's that the automotive-style li-ions are nontoxic and the raw materials in them are cheap, so there's not much incentive to recycle them. 3) Hydrogen generally costs $3-$15/kg, with the lower end from natural gas and the upper end from electrolysis. 4) Hydrogen is *not* the solution if you want power; fuel cells are priced per watt, not per watt hour. 5) The hydrogen cycle in a fuel cell vehicle with electricity as a source is 1/4 to 1/2 as efficient as that in a BEV. So no matter what your power source, you'll be requiring 2-4 times as much of it. Even if natural gas is the source, EVs are still usually 20-50% more efficient. 6) If you want to talk about resources, unlike EVs, fuel cells *do* use rare elements (in particular platinum). 7) FCVs cost about an order of magnitude more than EVs. For example, there's only one FCV available today that's not subsidized, and that's Toyota's FCHV-adv. It's by all standards a seemingly normal SUV, in terms of power, range, etc. But it costs over $8k a month to lease. One year of leasing of it would nearly pay for a Tesla Roadster outright -- a carbon fiber supercar that does 0-60 in under 4 seconds. 8) FCVs *require* infrastructure to do anything. EVs only require new infrastructure for away-from-home recharging, and a heck of a lot less of it.
I can keep going if you'd like. There's a reason why our Secretary of Energy tried to kill off our fuel cell programs. Tried. Congress forced him to keep them going, mainly due to amendments from people in districts who had been receiving the fuel cell research money.
A couple times a year I need a cargo van to move something big. Does that mean I should make a cargo van my daily commuter?
I love how you mention the inconvenience of having to rent or borrow for a long trip, but accept without question the inconvenience gasoline car drivers suffer in their *daily lives* of having to check whether they're running low on gasoline, and if so, drive out of their way to a gas station and fill up (incl. in inclement weather). If you need gas in a blizzard, you're out there filling up in a blizzard. EV drivers just plug in in their garage.
Not true. While the sort of batteries used in the Tesla Roadster are the same as are used in consumer electronics (18650-format cobalt cells), the types used in virtually all other modern EVs are not. Phosphate and spinel cells are still low volume products because most consumer electronics cares more about cost per Wh and energy density than they do about lifespan, stability, nontoxicity, and power density. And also, the packs themselves are not irrelevant costs, either, ignoring the cell costs. And neither are the costs of non-pack elements; have you priced an AC drivetrain and charger lately?
What is needed is, quite simply, VOLUME. Volume on every single part. Because that currently doesn't exist, outside of just the cells that just Tesla uses. Nothing that makes up a phosphate or manganese-based li-ion EV with an AC drivetrain is expensive from a raw materials standpoint. It's almost all capital and labor costs. Which means that it'll benefit hugely from mass production and process refinements.
Bah, that's only 26.4 kW. Aerovironment makes chargers as big as *800kW*.:) If I remember right, that's 800V and 1000A.
And yes, that requires cooling the cables so that you don't have to make them too thick. In the long run, I'd love to see the charger *provide* coolant to the vehicle so that it doesn't need to carry the weight or complexity of a powerful refrigeration system around; the same coolant that cools the cables could also cool the pack. But the TESCO unofficial-standard for rapid charging doesn't do that.
And Th!nk just demonstrated 15 minutes for 80% charging. Which the Subaru R1e supports, too. And the Leaf supports 30 minute charging for the same. The BYD F3DM takes 10 minutes to 80%, and the E6, 10 minutes to 50%. And on and on.
Rapid charging is becoming a reality. Yes, rapid chargers are going to be rarer than slow chargers, as they're more expensive (similar to gas stations on a per-pump price), and about the size of a vending machine. But we don't need them to be as common as gas stations, because they're only really needed for when you go on long trips. In your everyday life, you start each day with a full charge and never have to even think, "Gee, do I need to get gas today?", then have to go out of your way, sometimes in adverse weather, to go fill up.
Even better than car sharing, IMHO, is a towable generator like the AC Propulsion Long Ranger. Why rent or exchange a whole car when you could just rent or exchange a generator?
The answer to your question is, it's a lot easier for congress to allocate funds to maintain operations than it is for them to allocate funds to build a new system. So they tend to underfund system development, and pay for that many times over in increased operating costs. In particular, there's virtually no consideration given to ground-up redesign, even though we know we could gain a lot of benefits by doing so.
Yes, we do need to separate crew and cargo costs. Again, the Shuttle is an example of underfunded system development, as by merging the two together, they only had to develop one launch stack (there are a lot of even bigger development-cost compromises in the shuttle program, but that's a whole different story).
The SSTO issue is a problem. We need more basic research before we can feel confident in our ability to build a good SSTO. Scramjets or some kinds of metastable fuels could probably pull it off. New types of advanced composites might help. But it's really tough.
The Shuttle was a great research program. We learned an awful lot. The problem was that we turned what should have been a first generation reusable pilot project into a workhorse.
It might have been a suitable workhorse in some of its original incarnations. Might. But after the design compromises that led up to what we currently know as the shuttle, its chances for affordability were ruined.
It amazes me how many people think that what we're dealing with is a choice between outsourcing to industry vs. having the government do it. That's not the case. It's a choice between outsourcing to "small" (relatively) companies vs. outsourcing to huge corporate giants (Lockheed, Boeing, etc), which they currently do. The former should give much better pricing and innovation, at the downside of greater risk.
I don't know what you're talking about. Nelson et al are talking to Republicans, but they always were. Most of the Democrats are now talking reconciliation rather than trying to woo Snowe and the conservadems.
You mean the stimulus plan that the overwhelming majority of economists said was necessary to prevent a huge economic collapse, and a good chunk said was way too *small*? That stimulus package?
In a tough economy, esp. after a financial meltdown, the government is the only entity that can readily borrow money. In fact, they usually get good rates then because investors are looking for a safe place to keep their money. After the economy recovers, however, industry can more easily raise capital and rates for the government rise. So it's important for governments to *spend* during a downturn and *save* during an upturn.
We usually forget the latter part and just hand out tax cuts during upturns. Bad government -- no biscuit!
The whole focus on Obama is rather silly, in that it's neither the White House nor the House of Representatives that's holding up legislation. It's the senate and their "You Need 60 Votes To Pass Anything" rules.
The only thing I damn Obama for in that regard is not trying to beat the Senate into using the budget reconciliation process so we can get anything done. Bipartisanship is great, except for when one party decides that by unifying against the president on every single issue, they can weaken the opposing party politically, and in effect, basically shuts down the legislative process for political gain.
Don't read news articles -- read the paper. Here's a basic summary of how it works; they get into the numbers later:
"In this paper, we investitage energy storage in arrays of reverse-biased nano vacuum tubes, which are similar in design to nano plasma tubes, but contain little or no gas. The key design parameter is the gap size, the distance between the electrodes. Electrical breakdown in vacuum gaps has been studied or more that 80 years [8-10] for gap sizes above 200nm. However little is known about vacuum gaps in the nanometer range. We show that in reverse bias, the electric eld near nano-tip anodes can be orders of magnitudes larger than breakdown eld in conventional capacitors, varactor diodes, and nano plasma tubes. Since there are only residual gases between the electrodes in vacuum junctions, there is no Zener breakdown, no avalanche breakdown, and no material that could be ionized. Electrical breakdown is triggered by quantum mechanical tunneling of electrode material: electron eld emission on the cathode and ion eld emission on the anode. Because the energy barrier for electron eld emission is large and the barrier for ion eld emission even larger, the average energy density in reversed-biased nano vacuum tubes can exceed the energy density in solid state tunnel junctions and electrolytic capacitors. Since the inductance of the tubes is very small, the charge-discharge rates exceed batteries and conventional capacitors by orders of magnitude. Charging and discharging involves no faradaic reactions so the lifetime of nano vacuum tubes is virtually unlimited. The volumetric energy density is independent from the materials used as long as they can sustain the mechanical load, the electrodes are good conductors, and the mechanical supports are good insulators. Therefore, nano vacuum tubes can be built from environmentally friendly, non-noxious materials. Materials with a low density are preferable, since the gravimetric density is the ratio between the volumetric energy density and the average density of the electrodes and supports. Leakage currents are small, since the residual gases contain very few charged particles. Nano vacuum tubes can be fabricated with standard photo lithographic techniques [11] and could be easily integrated in integrated circuits as a rechargeable battery."
Digital quantum capacitors are completely different.:) Google the term; it's an interesting read. Basically, they use quantum effects to suppress arcing in an array of nanocapacitors. The best form uses a tungsten cathode and a CNT anode.
Oh, and I'll add that it's actually harder to do that bearing manufacture on the moon than it is on Earth, for two big reasons. One, pervasive, electrostatically-charged, abrasive dust means all equipment will wear down a lot faster. And two, milling and stamping metal releases a great deal of heat, which is easy to get rid of on Earth, but very difficult on the moon.
So much of you wrote is either ridiculously oversimplified from the real-world by many orders of magnitude (as well as omitting the dependency chains), or outright erroneous.
Here, because I have finite time, I'll just pick one. Let's pick one that sounds easy -- say, bearings. How are they produced?
* A steel wire of moderate diameter is fed in as the primary feedstock
* The wire is chopped into pieces that will become shaped into the ball
* The pieces are stamped between hemispherical dies. This produces an approximate "bearing", but iis uneven and is of the wrong temper.
* The balls flow through a rotary kiln on a conveyor
* The balls roll into grinding and lapping machines -- pairs of discs rotating at different speeds. After several passes the bearing is approximately the final shape.
* The bearings are gauged and sorted by being rolled between divergent blades.
Each one of the steps involves multiple component that will wear, and as with any factory, things can break (which is why factories have maintenance crews).
Your typical ball bearing plant costs hundreds of millions to several billion dollars. Now, it makes up for that with having way more throughput than would be needed on the moon, but therein lies yet another problem. As you scale down, you end up needing dramatically more labor per unit. But labor is a finite resource. Each additional person you add to the lunar labor pool also increases the resource demand. And you can see all of the hardware just needed to produce ball bearings. There are literally millions of parts needed for even a "simplified" colony on the moon, everything from making up EVA suits to CO2 scrubbers to duct fans to greenhouse glazing to wheels and on and on and on. It's simply impossible to have a small population hand make them all.
And here we're just talking about *part* dependencies. Chemical dependencies are even more daunting than part dependencies.
(oh, and by the way: your notion of having mining vehicles be powered by solar panels on their roof A) belies an ignorance of the power density of solar energy (no, "slowing down" doesn't cut it, and not only because so many of the minerals you need are in ppm quantities), B) implies shutting down operations for two weeks at a time due to the lunar night, and C) means that you need to be able to build freaking solar panels on the moon, since they do degrade -- that's as hard as making computer chips.
1. The iron is extracted from a powdered hydrogen reduced mineral such as ilmenite by means of reaction with carbon monoxide gas, which results in formation of a volatile compound, iron carbonyl (b.p. 103C).
Just to pick one: excavator consumables:
* Batteries (5-10 year lifespan if a durable chemistry but heavy use)
* Lubricants
* Blades
* Motors (high power electronics wear out eventually)
* Inverter (high power electronics wear out eventually)
* Charger (high power electronics wear out eventually)
* Bearings
* Hydraulic fluid (the occasional leak)
* Glass (if the operator looks outside directly -- video cameras and displays otherwise), damaged by the occasional bit of ejected rock or slowly eaten away by corrosive lunar dust until hard to see through.
* Wheels (friction wear)
* Fenders/hubs/anywhere else where wheel-ejected debris impacts the body and slowly abrades it (regolith is a very abrasive powder, and there's no air to slow it down)
* Any sort of electronics -- load sensors, temperature sensors, speed sensors, telematics gear, communications gear, etc. All will break eventually.
And on and on. And want me to trace any of those back? Want me to move onto #2 and #3, which get worse?
Plus, that approach for iron mining on the moon seems needlessly complex. Regolith is about 1% elemental iron. All you need is a magnetic comb and something to churn the regolith. Your mining and casting equipment will still wear out, spawning long, painful dependency chains, but you avoid problematic intermediary stages.
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It is. Contrary to common perception, both NASA and welfare are very small parts of our federal budget. They're just very visible things.
The reports I've seen say it'll probably be similar to the Jupiter Direct proposal that a number of NASA engineers had been proposing as an alternative to the problem-plagued Ares rocket development. So still based on shuttle hardware, but probably a better design.
Then they charge more. Any more questions?
You really have no sense of where government money goes, do you? TANF (federally-funded welfare) is $16.5B. By contrast, the latest Pentagon budget request is $768.2B.
Welfare is a really tiny portion of our total expenses.
Hanson owns NASA now.
Has he been appointed Grand Poobah of the Illuminati yet? What is he going to have the Trilateral Commission do next?
1) Modern automotive-style li-ion battery lifespans are similar to transmission lifespans or other vehicle component lifespans. Fuel cells, on the other hand, have about half the lifespan of said batteries.
2) It's not that li-ion batteries are difficult to recycle; it's that the automotive-style li-ions are nontoxic and the raw materials in them are cheap, so there's not much incentive to recycle them.
3) Hydrogen generally costs $3-$15/kg, with the lower end from natural gas and the upper end from electrolysis.
4) Hydrogen is *not* the solution if you want power; fuel cells are priced per watt, not per watt hour.
5) The hydrogen cycle in a fuel cell vehicle with electricity as a source is 1/4 to 1/2 as efficient as that in a BEV. So no matter what your power source, you'll be requiring 2-4 times as much of it. Even if natural gas is the source, EVs are still usually 20-50% more efficient.
6) If you want to talk about resources, unlike EVs, fuel cells *do* use rare elements (in particular platinum).
7) FCVs cost about an order of magnitude more than EVs. For example, there's only one FCV available today that's not subsidized, and that's Toyota's FCHV-adv. It's by all standards a seemingly normal SUV, in terms of power, range, etc. But it costs over $8k a month to lease. One year of leasing of it would nearly pay for a Tesla Roadster outright -- a carbon fiber supercar that does 0-60 in under 4 seconds.
8) FCVs *require* infrastructure to do anything. EVs only require new infrastructure for away-from-home recharging, and a heck of a lot less of it.
I can keep going if you'd like. There's a reason why our Secretary of Energy tried to kill off our fuel cell programs. Tried. Congress forced him to keep them going, mainly due to amendments from people in districts who had been receiving the fuel cell research money.
A couple times a year I need a cargo van to move something big. Does that mean I should make a cargo van my daily commuter?
I love how you mention the inconvenience of having to rent or borrow for a long trip, but accept without question the inconvenience gasoline car drivers suffer in their *daily lives* of having to check whether they're running low on gasoline, and if so, drive out of their way to a gas station and fill up (incl. in inclement weather). If you need gas in a blizzard, you're out there filling up in a blizzard. EV drivers just plug in in their garage.
Not true. While the sort of batteries used in the Tesla Roadster are the same as are used in consumer electronics (18650-format cobalt cells), the types used in virtually all other modern EVs are not. Phosphate and spinel cells are still low volume products because most consumer electronics cares more about cost per Wh and energy density than they do about lifespan, stability, nontoxicity, and power density. And also, the packs themselves are not irrelevant costs, either, ignoring the cell costs. And neither are the costs of non-pack elements; have you priced an AC drivetrain and charger lately?
What is needed is, quite simply, VOLUME. Volume on every single part. Because that currently doesn't exist, outside of just the cells that just Tesla uses. Nothing that makes up a phosphate or manganese-based li-ion EV with an AC drivetrain is expensive from a raw materials standpoint. It's almost all capital and labor costs. Which means that it'll benefit hugely from mass production and process refinements.
Bah, that's only 26.4 kW. Aerovironment makes chargers as big as *800kW*. :) If I remember right, that's 800V and 1000A.
And yes, that requires cooling the cables so that you don't have to make them too thick. In the long run, I'd love to see the charger *provide* coolant to the vehicle so that it doesn't need to carry the weight or complexity of a powerful refrigeration system around; the same coolant that cools the cables could also cool the pack. But the TESCO unofficial-standard for rapid charging doesn't do that.
And Th!nk just demonstrated 15 minutes for 80% charging. Which the Subaru R1e supports, too. And the Leaf supports 30 minute charging for the same. The BYD F3DM takes 10 minutes to 80%, and the E6, 10 minutes to 50%. And on and on.
Rapid charging is becoming a reality. Yes, rapid chargers are going to be rarer than slow chargers, as they're more expensive (similar to gas stations on a per-pump price), and about the size of a vending machine. But we don't need them to be as common as gas stations, because they're only really needed for when you go on long trips. In your everyday life, you start each day with a full charge and never have to even think, "Gee, do I need to get gas today?", then have to go out of your way, sometimes in adverse weather, to go fill up.
all that frozen Climate Change
Someone needs to learn the difference between:
* "Global" and "Local"
* "Climate" and "Weather".
Even better than car sharing, IMHO, is a towable generator like the AC Propulsion Long Ranger. Why rent or exchange a whole car when you could just rent or exchange a generator?
The answer to your question is, it's a lot easier for congress to allocate funds to maintain operations than it is for them to allocate funds to build a new system. So they tend to underfund system development, and pay for that many times over in increased operating costs. In particular, there's virtually no consideration given to ground-up redesign, even though we know we could gain a lot of benefits by doing so.
Yes, we do need to separate crew and cargo costs. Again, the Shuttle is an example of underfunded system development, as by merging the two together, they only had to develop one launch stack (there are a lot of even bigger development-cost compromises in the shuttle program, but that's a whole different story).
The SSTO issue is a problem. We need more basic research before we can feel confident in our ability to build a good SSTO. Scramjets or some kinds of metastable fuels could probably pull it off. New types of advanced composites might help. But it's really tough.
Your metaphor-fu needs practice, grasshopper.
The Shuttle was a great research program. We learned an awful lot. The problem was that we turned what should have been a first generation reusable pilot project into a workhorse.
It might have been a suitable workhorse in some of its original incarnations. Might. But after the design compromises that led up to what we currently know as the shuttle, its chances for affordability were ruined.
It amazes me how many people think that what we're dealing with is a choice between outsourcing to industry vs. having the government do it. That's not the case. It's a choice between outsourcing to "small" (relatively) companies vs. outsourcing to huge corporate giants (Lockheed, Boeing, etc), which they currently do. The former should give much better pricing and innovation, at the downside of greater risk.
I don't know what you're talking about. Nelson et al are talking to Republicans, but they always were. Most of the Democrats are now talking reconciliation rather than trying to woo Snowe and the conservadems.
You mean the stimulus plan that the overwhelming majority of economists said was necessary to prevent a huge economic collapse, and a good chunk said was way too *small*? That stimulus package?
In a tough economy, esp. after a financial meltdown, the government is the only entity that can readily borrow money. In fact, they usually get good rates then because investors are looking for a safe place to keep their money. After the economy recovers, however, industry can more easily raise capital and rates for the government rise. So it's important for governments to *spend* during a downturn and *save* during an upturn.
We usually forget the latter part and just hand out tax cuts during upturns. Bad government -- no biscuit!
The whole focus on Obama is rather silly, in that it's neither the White House nor the House of Representatives that's holding up legislation. It's the senate and their "You Need 60 Votes To Pass Anything" rules.
The only thing I damn Obama for in that regard is not trying to beat the Senate into using the budget reconciliation process so we can get anything done. Bipartisanship is great, except for when one party decides that by unifying against the president on every single issue, they can weaken the opposing party politically, and in effect, basically shuts down the legislative process for political gain.
Whoops -- sorry for the bold. I shuold porff raed.
Don't read news articles -- read the paper. Here's a basic summary of how it works; they get into the numbers later:
"In this paper, we investitage energy storage in arrays of reverse-biased nano vacuum tubes, which are similar in design to nano plasma tubes, but contain little or no gas. The key design parameter is the gap size, the distance between the electrodes. Electrical breakdown in vacuum gaps has been studied or more that 80 years [8-10] for gap sizes above 200nm. However little is known about vacuum gaps in the nanometer range. We show that in reverse bias, the electric eld near nano-tip anodes can be orders of magnitudes larger than breakdown eld in conventional capacitors, varactor diodes, and nano plasma tubes. Since there are only residual gases between the electrodes in vacuum junctions, there is no Zener breakdown, no avalanche breakdown, and no material that could be ionized. Electrical breakdown is triggered by quantum mechanical tunneling of electrode material: electron eld emission on the cathode and ion eld emission on the anode. Because the energy barrier for electron eld emission is large and the barrier for ion eld emission even larger, the average energy density in reversed-biased nano vacuum tubes can exceed the energy density
in solid state tunnel junctions and electrolytic capacitors. Since the inductance of the tubes is very small, the charge-discharge rates exceed batteries and conventional capacitors by orders of magnitude. Charging and discharging involves no faradaic reactions so the lifetime of nano vacuum tubes is virtually unlimited. The volumetric energy density is independent from the materials used as long as they can sustain the mechanical load, the electrodes are good conductors, and the mechanical supports are good insulators. Therefore, nano vacuum tubes can be built from environmentally friendly, non-noxious materials. Materials with a low density are preferable, since the gravimetric density is the ratio between the volumetric energy density and the average density of the electrodes and supports. Leakage currents are small, since the residual gases contain very few charged particles. Nano vacuum tubes can be fabricated with standard photo lithographic techniques [11] and could be easily integrated in integrated circuits as a rechargeable battery."
Digital quantum capacitors are completely different. :) Google the term; it's an interesting read. Basically, they use quantum effects to suppress arcing in an array of nanocapacitors. The best form uses a tungsten cathode and a CNT anode.
Oh, and I'll add that it's actually harder to do that bearing manufacture on the moon than it is on Earth, for two big reasons. One, pervasive, electrostatically-charged, abrasive dust means all equipment will wear down a lot faster. And two, milling and stamping metal releases a great deal of heat, which is easy to get rid of on Earth, but very difficult on the moon.
So much of you wrote is either ridiculously oversimplified from the real-world by many orders of magnitude (as well as omitting the dependency chains), or outright erroneous.
Here, because I have finite time, I'll just pick one. Let's pick one that sounds easy -- say, bearings. How are they produced?
* A steel wire of moderate diameter is fed in as the primary feedstock
* The wire is chopped into pieces that will become shaped into the ball
* The pieces are stamped between hemispherical dies. This produces an approximate "bearing", but iis uneven and is of the wrong temper.
* The balls flow through a rotary kiln on a conveyor
* The balls roll into grinding and lapping machines -- pairs of discs rotating at different speeds. After several passes the bearing is approximately the final shape.
* The bearings are gauged and sorted by being rolled between divergent blades.
Each one of the steps involves multiple component that will wear, and as with any factory, things can break (which is why factories have maintenance crews).
Your typical ball bearing plant costs hundreds of millions to several billion dollars. Now, it makes up for that with having way more throughput than would be needed on the moon, but therein lies yet another problem. As you scale down, you end up needing dramatically more labor per unit. But labor is a finite resource. Each additional person you add to the lunar labor pool also increases the resource demand. And you can see all of the hardware just needed to produce ball bearings. There are literally millions of parts needed for even a "simplified" colony on the moon, everything from making up EVA suits to CO2 scrubbers to duct fans to greenhouse glazing to wheels and on and on and on. It's simply impossible to have a small population hand make them all.
And here we're just talking about *part* dependencies. Chemical dependencies are even more daunting than part dependencies.
(oh, and by the way: your notion of having mining vehicles be powered by solar panels on their roof A) belies an ignorance of the power density of solar energy (no, "slowing down" doesn't cut it, and not only because so many of the minerals you need are in ppm quantities), B) implies shutting down operations for two weeks at a time due to the lunar night, and C) means that you need to be able to build freaking solar panels on the moon, since they do degrade -- that's as hard as making computer chips.
1. The iron is extracted from a powdered hydrogen reduced mineral such as ilmenite by means of reaction with carbon monoxide gas, which results in formation of a volatile compound, iron carbonyl (b.p. 103C).
Dependencies:
* Excavators
* Transport (trucks, conveyors, etc)
* Ball mill
* Hydrogen
* Purified carbon monoxide
* Reaction chamber
* Compressor
* Tanks
* Heat exchanger
* Radiator
* Solid tailings separation (probably quite complex)
* Solid tailings removal/disposal
* Gasseous tailings separation and exhausting (probably quite complex)
Just to pick one: excavator consumables:
* Batteries (5-10 year lifespan if a durable chemistry but heavy use)
* Lubricants
* Blades
* Motors (high power electronics wear out eventually)
* Inverter (high power electronics wear out eventually)
* Charger (high power electronics wear out eventually)
* Bearings
* Hydraulic fluid (the occasional leak)
* Glass (if the operator looks outside directly -- video cameras and displays otherwise), damaged by the occasional bit of ejected rock or slowly eaten away by corrosive lunar dust until hard to see through.
* Wheels (friction wear)
* Fenders/hubs/anywhere else where wheel-ejected debris impacts the body and slowly abrades it (regolith is a very abrasive powder, and there's no air to slow it down)
* Any sort of electronics -- load sensors, temperature sensors, speed sensors, telematics gear, communications gear, etc. All will break eventually.
And on and on. And want me to trace any of those back? Want me to move onto #2 and #3, which get worse?
Plus, that approach for iron mining on the moon seems needlessly complex. Regolith is about 1% elemental iron. All you need is a magnetic comb and something to churn the regolith. Your mining and casting equipment will still wear out, spawning long, painful dependency chains, but you avoid problematic intermediary stages.