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The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way. Solar Panel Cables And Wires

the very solar cells the process produces! Brilliant!

Oh wait...um...I'm sure we can get some generators (and fuel.. and oxidizer) on Amazon. They deliver to the Moon, right?

They tried summoning them through the power of wishful thinking, but that didn't work so well. Unfortunately some bootstrapping is required.

That doesn't sound correct, according to my calculations it would be 73 settlements, and even that is assuming it's a tall six pack the settlers don't stay up late.

the very solar cells the process produces! Brilliant! Oh wait...um...I'm sure we can get some generators (and fuel.. and oxidizer) on Amazon. They deliver to the Moon, right?

the very solar cells the process produces! Brilliant!

Oh wait...um...I'm sure we can get some generators (and fuel.. and oxidizer) on Amazon. They deliver to the Moon, right?

Maybe you're just trying to be funny, but it really does seem like you think you have some sort of point here. If you really are trying to make a point, it's utter nonsense. Yes, the power to make the first solar cell can't come from the solar cell that is to be produced. Congratulations for your grasp on basic causality. In the real universe, where engineers grasp causality as well, they know that they need to start with a power source not produced in situ by the machine. That can, in fact, still be solar cells, just obviously not ones made from the electricity that they will produce after they are made.

Once a power source is set up and this machine is being provided with the raw materials and power to produce solar panels, you can grow a solar farm and, the more and more solar panels, the more and more power and, presumably, the faster you can produce new panels. Obviously this hits an upper limit at the point where the machine is producing panels as fast as we can. Its not a Von Neumann machine after all. Whether you build up the power supply for the panel-maker first, or you power other processes at the same time will vary. Once you have max power to the machine though, you can pretty much just produce panels to power your habitat, factories, moon rovers, etc.

There are other potential limitations and questions, of course. For example, are there other consumables? They make solar cells and protective glass out of regolith, but what about wiring, connectors, etc.? Then there are other needed components like battery controllers, breaker boxes, and other electrical equipment. If those are not produced in situ then they need to be brought along. There is also the question of if other consumables aside from regolith are needed for production. Other chemicals? Replacement electrodes, etc.? Requirements like this still don't ruin the idea of in situ resource usage. As long as you can ultimately get more power per unit mass shipped, then you're ahead. Even just producing 50% more solar power than you could have by just shipping the equivalent mass in solar panels then you're doing well

but what about wiring, connectors, etc.?

but what about wiring, connectors, etc.?

The wiring might not be a problem. One of the extracted elements is aluminum, which is very conductive. Aluminum provides a better conductivity to weight ratio than copper, and therefore is also used for wiring power grids, including overhead power transmission lines and local power distribution lines, as well as for power wiring of some airplanes. In North American residential construction, aluminum wire was used for wiring entire houses for a short time from the 1960s to the mid-1970s during a period of high copper prices. https://en.wikipedia.org/wiki/... [wikipedia.org]

I remember aluminum wiring in homes back in the 70s. Anytime a copper wire needed to be connected to an aluminum wire, an antioxidant paste had to be applied to the connection and a specialize AL/CU connector had to be used. We also had to be sure to use the correct connector for CU/CU connections and AL/AL connections. The proper circuit breaker box, switches, and receptacles also had to be used for the selected wire type. It added complexity to the job.

Luckily there's not a lot of free oxygen on the moon so that anti oxidant paste wouldn't be needed.

Not a lot of copper either, so the complexity of bi-metal junctions isn't an issue.

Luckily there's not a lot of free oxygen on the moon so that anti oxidant paste wouldn't be needed.

Luckily there's not a lot of free oxygen on the moon so that anti oxidant paste wouldn't be needed.

...unless of course, you're planning on having any wiring in any place where humans are, with their...um, I mean, OUR... annoying need for oxygen, because then you might need to have oxygen and that paste they were talking about. Overheard at a robot comedy club: Quick impression of a human: "Waaa, look at me, I'm a human, I need oxygen, waaa... my cells are dying! My CELLS!" Feh. Humans. So weak and squishy and you can't even upgrade them without replacing them outright... I mean, it takes literally

Have you worked with electric water heaters? If so you're probably familiar with the sacrificial anode, typically made of aluminum or magnesium. It selectively corrodes so that the steel parts of the water heater will not. With aluminum in contact with most other metals you get a galvanic reaction that is going to corrode the aluminum, and aluminum oxide is a very good insulator, so the end of the very conductive aluminum wire becomes non-conductive. Yeah, Aluminum wiring was a real mess. On the other hand, in a vacuum with no oxygen, it might work out a lot better.

Aluminum wiring always has a bit of an oxidation problem. Aluminum is a very good conductor, but aluminum oxide is a very good insulator and a very thin coating of it could wreck a connection to an aluminum wire, even between two aluminum wires. On the moon, at least outside the habitat, that should not be a problem at all .

This is a pretty well-solved problem at this point, though, whether through oxygen shield compounds or sacrificial anodes. You can buy breakers and receptacles designed to have aluminum wiring attached to them.

Yeah, I was more grousing about wiring problems in old houses than modern usage. Certainly it would not be a problem on the Moon.

You can look at that as a bad thing (connectors have to be a little more sophisticated) or a good thing (wires have self-healing insultation).

Self-healing insulation. Now that is a way to look on the bright side. I wonder how practical that is in, for example electric motor windings where the motor may overheat and the insulation burns off?

The point is that anything flown up from earth is incredibly expensive - more than the price of gold.

The point is that anything flown up from earth is incredibly expensive - more than the price of gold.

Huh? SpaceX Falcon runs around ~$2500/kg to LEO if you're using the max payload. Gold is currently selling for $1874/oz or about $58000/kg. Or are you talking about space hardware being expensive?

If it didn't have big problems, they'd be angling to build a factory on the moon to supply other projects, instead of just offering to "market the technology."

The money has to come from somewhere. Everyday people are not gonna be customers of this technology, but NASA is government funded and gets taxpayer money, and can allocate some to the Blue Alchemist project.

This is very exciting. I always thought you'd have to separate the aluminum and iron and silicon from each other by some means - I remember reading about some engineers proposing filtering out crystallized silicon from a silicon-aluminum alloy in the molten state, that you would get from magma electroly

Yeah, this sounds like a extremely productive improvement over the original electrolytic refinery Sadoway developed for NASA a few years back (and which is slated to be deployed at a tiny-scale test project in the early phases of the moon base) , which only extracted steel and I think aluminum, with less common metals being a promising future option with further electrolysis refinement. I figured it would take a lot more development before bulk semiconductor quality silicon was an option. If local solar panel production is possible from very early on that would dramatically streamline lunar development. (Not to mention Mars and asteroids, if the technology is compatible with available regolith)

Not only will making solar panels locally be a huge long-term advantage, producing silicon will also *greatly* increase the yield of the primary short-term export: oxygen. Which is both extremely ecologically important, and also ~80% of the propellant mass for methane rockets, and even more for hydrogen rockets. Even if you still have to bring the fuel from Earth, not having to also bring the huge mass of oxygen to make it useful is a dramatic improvement.

As for regolith composition, as I recall it's mostly silicon dioxide (a.k.a. quartz, the most chemically stable form of silicon) with some iron oxide (FeO) and aluminum oxide (Al2O3). And given the elemental ratios, most of the oxygen is bound to silicon, so refining that would dramatically increase the oxygen yields per ton of regolith. The average elemental ratio of the most lunar regolith components is ~43% oxygen, 21% silicon,10% aluminum and 9% iron, though the iron:aluminum ratio changes with altitude.

At a wild guess the electrolysis chamber is some sort of ceramic, they tend to be the first choice for extreme chemical and thermal stability. Metals melt at relatively low temperatures, and tend to be highly reactive, I'm not sure why you even bother mentioning platinum in that context. Steel has a much higher melting point, to say nothing of quartz. The electrodes are a bigger challenge, since they must be directly involved in the chemical reactions without reacting themselves.

Exactly. Trying to create a business model when getting in on the ground floor is a losing proposition. When it comes to off-world outposts I like to invoke the analogy of a military fort in largely undeveloped wilderness as the best terrestrial analog. You build a fort for purely strategic reasons, usually to secure control over something important like a river junction or remote but valuable mine. And it's initially pure expense - it has no exports, nor industry, nor agriculture to support itself, and

The nights on the moon are two weeks long.

Also, there is no convective cooling, so the panels will get very hot, about 125C or 260F. Solar panels don't work well or last long at those temperatures.

The long nights are a potential issue. However, there are areas at the poles where you can get sunlight pretty much all the time if you build on the right hills and ridges, though you might need swiveling mounts. If you have to build nearer the equator that may not help much. It is essentially a question of scale though. If you have a small research station, you can't get power from the poles at the equator. If you have a big colony, you can find a solution to get power from the poles, such as running power lines. It's 1697 miles max from any point on the moon to one of the poles. If you don't want to build anything at the poles, you can have stations 3393 miles apart and one will always be in sunlight. Of course, the larger the scale of your colony, the easier it is, relatively speaking, to just have enough batteries to last two weeks. You could also use power beaming with microwaves, sending to a satellite and then beaming it back down. With no atmosphere, a lot of the technical problems of power beaming on Earth are non-issues. In short, you identified a potential issue, but it's not an unsolvable issue.

As for the lack of convective cooling, I'm not sure if you've noticed, but a lot of things in space are powered by solar panels and they work just fine. Of course, that's generally by emitting out of the back of the panel into the cold of space. On the moon, the back of the panel will have the surface of the moon, which is not as cold as space. That can get very hot in direct sunlight, but not so much when in shade. There are a lot of good reasons to think that you could use the moon itself as a good heat sink. Otherwise, you can set up a reflective arrangement to send the heat off into space. So, once again you have identified a potential issue, but not an unsolvable one.

I expect that for the foreseeable future humans will only spend one lunar day on the surface at a time.

Aside from the power issues, the lunar dust destroys equipment fast. Since it hasn't been worn down by wind and water, it is very sharp. A lot of the gear they take down, like EV suits, will be trashed after a couple of weeks anyway.

Yep. It's called an extended weekend when all the heavy industry has to shut down while the outpost falls back on batteries, nuclear backup power, and perhaps burning some of the aluminum or silicon produced during the week to generate power.

There's no convective cooling, but plenty of conductive cooling into the ground. According to subsurface probes left by the Apollo missions, at a depth of just one meter the temperatures become extremely stable, fluctuating by only a degree or two.

There's no atmosphere on the moon, so no wind or rain or other elements to deal with either. You don't need rigid solar panels, you can just lay out giant solar panel "matts" from rolls of flexible solar cells.

There's no atmosphere on the moon, so no wind or rain or other elements to deal with either. You don't need rigid solar panels, you can just lay out giant solar panel "matts" from rolls of flexible solar cells.

There's no wind or rain, but there are micrometeorites. Also, the lunar dust is not blown around by actual wind, but it is believed that it can migrate around from electrostatic forces driven by the solar wind. Basically some particles of moon dust may be leaping into the air and dropping back down over and over. That's not an unmanageable problem, but it does make it a little trickier than just lying them on the ground and expecting them to never get nicked and scratched or covered in dust.

now hopefully they can manufacture oxygen from materials on the moon.

now hopefully they can manufacture oxygen from materials on the moon.

Oxygen is no problem. Lunar regolith is 40% oxygen.

The problem is getting enough hydrogen and nitrogen.

And phosphorus, potassium, carbon. If you want to grow stuff to eat.

And phosphorus, potassium, carbon. If you want to grow stuff to eat.

Those are all available in lunar regolith in concentrations similar to the earth's crust.

Nitrogen and hydrogen are not.

Hopefully as we start developing the moon in earnest we'll find mineral deposits rich in such things. For now we're really only looking to utilize the resources we can positively identify from orbital surveys and robot probes that barely scratch the uppermost layers of the surface.

If not... well then I anticipate a booming import market for ammonia and petroleum. (carbon being another thing the moon seems short on, though the asteroid remnants in about 70% of impact craters should contain generous if incon

I should clarify - yes the crust may contain similar amounts of carbon... but on Earth we've had billions of years of life concentrating subsurface carbon (released as volcanic CO2) into an incredibly carbon-rich "surface scum" of life. If we want a similar ecosystem in a moon base we're going to need a lot more carbon than is easily accessible from its crust.

Have they made it to orbit, yet?

They also still haven't explained what went wrong with their NS25 [space.com] failure either.

These guys can't even get to orbit. Next they'll be telling us of their plans to colonize Alpha Centauri.

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