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#1 2011-12-17 16:34:37

Terraformer
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From: The Fortunate Isles
Registered: 2007-08-27
Posts: 3,906
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Developing the cis-Lunar economy and infrastructure

What do we need to start fuel mining? I can identify:

  • A supply depot in LEO and EML1 - say 2-4 crew each

  • A fuel craft to go between the two and another such craft to go from EML1 to the Lunar base (automated)

  • A manned craft that will go between the bases - say a Dragon capsule attached to a Bigelow module? (x2)

  • Mining equipment for the Lunar base

  • Base habitat

The automated fuel carriers can be designed as a stretched upper stage, so launching it is essentially free. Similarly, so can the fuel tanks in the depots. Say we use a Sundancer module in each of the depots - at 10 tonnes each, we're talking about launching 20 tonnes, though half of this will remain in LEO. Perhaps, then, the LEO depot can be launched all in one on a basic Falcon 9, with a stretched upper stage, and a Falcon 9 Heavy with a stretched upper stage may be able to throw the entire EML1 depot straight there. That's the two depots sorted, in two launches. Now, it might make more sense to use two F9H launches, and throw in additional fuel in the first one. If we do this, we could refuel some of our upper stages and use them to throw more mass at Luna.

Now, for the base. It may be that we could use the additional fuel in the first depot to launch directly there, but it's a delta-V of 6km/s to land. It might take two F9H launches. What we need is a habitat (say a Sundancer buried under regolith for added radiation protection), mining equipment (which is going to likely be jackhammer's capable of working at cryogenic temperatures, and then something to melt the ice dust), and a power array (possibly, an inflatable tower to take advantage of the near constant sunlight - it will need to rotate). I'm not to sure about how much this would mass.

Of course, we need our automated transport craft. Whichever craft delivers the base should be good enough to serve this role for the EML1-Luna trip, and the one used for the LEO-EML1 trip could have an initial payload of fuel for the manned craft. I don't know how this is going to work out yet, but probably somewhere along those lines.

Then we need to get our humans there. Something along the lines of a Dragon capsule docked to a cylindrical service module and it's upper stage for propulsion is what I'm thinking of at the moment. We could fit in maybe 9 people, especially given that that's only for the very first ride to orbit. Offload 3 people to get the LEO depot running, then burn to the EML1 depot and offload it's crew of 3, while topping up the tanks for the EML1-Luna trip (which is ~2.5km/s, so not much). We may have to risk stranding the crew for a while, before we can refuel it from in-situ LH2/LOX (modding the upper stages to hold hydrogen, as well as stretching them, will be required...) to reduce costs, but they'll have enough supplies for 6 months anyway. This would probably be a single F9H launch as well...

Now we've got the components of the basic infrastructure in place. Depending on how difficult it is to electrolyse water in microgravity, the fuel may be transported to the EML1 depot in the form of water, with only that which is needed for the manned transport and the automated trip being produced at the base, to save on launching solar panels to the Luna surface.

After 6 months, another manned craft, similar to the first, will be launched, along with a Dragon capsule, and will proceed through the system, allowing the crew to be replaced. Now that fuel on orbit is effectively free from the standpoint of increasing the systems capabilities, we can begin to enlarge the base into a proper mining base, with enough capability.

I know this isn't a very detailed post, but it's a start. I'd really like to get some numbers down so we can start looking at the cost of this thing (hopefully under a billion dollars upfront cost).


Use what is abundant and build to last

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#2 2011-12-17 16:51:59

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

Terraformer wrote:

What do we need to start fuel mining? I can identify:

  • A supply depot in LEO and EML1 - say 2-4 crew each

  • A fuel craft to go between the two and another such craft to go from EML1 to the Lunar base (automated)

  • A manned craft that will go between the bases - say a Dragon capsule attached to a Bigelow module? (x2)

  • Mining equipment for the Lunar base

  • Base habitat

The automated fuel carriers can be designed as a stretched upper stage, so launching it is essentially free. Similarly, so can the fuel tanks in the depots. Say we use a Sundancer module in each of the depots - at 10 tonnes each, we're talking about launching 20 tonnes, though half of this will remain in LEO. Perhaps, then, the LEO depot can be launched all in one on a basic Falcon 9, with a stretched upper stage, and a Falcon 9 Heavy with a stretched upper stage may be able to throw the entire EML1 depot straight there. That's the two depots sorted, in two launches. Now, it might make more sense to use two F9H launches, and throw in additional fuel in the first one. If we do this, we could refuel some of our upper stages and use them to throw more mass at Luna.

Now, for the base. It may be that we could use the additional fuel in the first depot to launch directly there, but it's a delta-V of 6km/s to land. It might take two F9H launches. What we need is a habitat (say a Sundancer buried under regolith for added radiation protection), mining equipment (which is going to likely be jackhammer's capable of working at cryogenic temperatures, and then something to melt the ice dust), and a power array (possibly, an inflatable tower to take advantage of the near constant sunlight - it will need to rotate). I'm not to sure about how much this would mass.

Of course, we need our automated transport craft. Whichever craft delivers the base should be good enough to serve this role for the EML1-Luna trip, and the one used for the LEO-EML1 trip could have an initial payload of fuel for the manned craft. I don't know how this is going to work out yet, but probably somewhere along those lines.

Then we need to get our humans there. Something along the lines of a Dragon capsule docked to a cylindrical service module and it's upper stage for propulsion is what I'm thinking of at the moment. We could fit in maybe 9 people, especially given that that's only for the very first ride to orbit. Offload 3 people to get the LEO depot running, then burn to the EML1 depot and offload it's crew of 3, while topping up the tanks for the EML1-Luna trip (which is ~2.5km/s, so not much). We may have to risk stranding the crew for a while, before we can refuel it from in-situ LH2/LOX (modding the upper stages to hold hydrogen, as well as stretching them, will be required...) to reduce costs, but they'll have enough supplies for 6 months anyway. This would probably be a single F9H launch as well...

Now we've got the components of the basic infrastructure in place. Depending on how difficult it is to electrolyse water in microgravity, the fuel may be transported to the EML1 depot in the form of water, with only that which is needed for the manned transport and the automated trip being produced at the base, to save on launching solar panels to the Luna surface.

After 6 months, another manned craft, similar to the first, will be launched, along with a Dragon capsule, and will proceed through the system, allowing the crew to be replaced. Now that fuel on orbit is effectively free from the standpoint of increasing the systems capabilities, we can begin to enlarge the base into a proper mining base, with enough capability.

I know this isn't a very detailed post, but it's a start. I'd really like to get some numbers down so we can start looking at the cost of this thing (hopefully under a billion dollars upfront cost).

I think a lot depends on whether there really are clumps of water ice on or near the surface. If there are then this should be relatively straightforward.  AS for the jackhammer, might it not help to use a microwave heater to loosen the permafrost or ice before the jackhammer gets going.


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#3 2011-12-17 17:43:27

Terraformer
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Re: Developing the cis-Lunar economy and infrastructure

Microwaves only work on liquid water. You can microwave an ice cube and it won't melt, as long as it's dry to start with.

We know there are sheets of ice in polar craters which are at least 2m thick. The trouble is, it's at 30K, so it's very, very, very strong. Hopefully, though, it'll be brittle enough to shatter easily, so that we can get it out. Some concentrated solar power might be helpful. At least we'll be able to store the hydrogen and oxygen easily enough in the craters.

I think the biggest part in terms of launch costs is going to be the actually Lunar base: we might be able to get the mass required down to 50 tonnes, but the fuel required to get it there is going to be significant. One of the problems is, while the actually mass that can be launched is ~50 tonnes on the F9H, we can't exactly launch a Sundancer module, Dragon, and Solar array on the same launch, even if it could theoretically cope with the mass. Fortunately, any extra payload can be used up by the fuel we'll need, and any fuel launches can be used for adding extra capability to the depots, so no upper stage need be wasted.


Use what is abundant and build to last

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#4 2011-12-17 19:20:41

Adaptation
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Registered: 2011-11-22
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Re: Developing the cis-Lunar economy and infrastructure

I assure you that microwaves do work on ice, just not as well.

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#5 2011-12-18 04:56:28

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Developing the cis-Lunar economy and infrastructure

I can assure you that in space Microwave transmission works much better than here on Earth.

One way to build things on the Moon is to simply put regolith in a mold and microwave it making quick easy bricks.

Some plans to do that with making roads just involve a rover microwaving the regolith to make a hard surface.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#6 2011-12-18 05:31:01

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

Grypd wrote:

I can assure you that in space Microwave transmission works much better than here on Earth.

One way to build things on the Moon is to simply put regolith in a mold and microwave it making quick easy bricks.

Some plans to do that with making roads just involve a rover microwaving the regolith to make a hard surface.

That sounds great to me. That's exactly the sort of technology we should be looking to develop. We should make full use of energy (which comes from the sun and doesn't require replenishment from Earth) in our surface techologies.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#7 2011-12-20 17:39:51

Terraformer
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Re: Developing the cis-Lunar economy and infrastructure

Only if it's abundant enough... bear in mind we need at least around 15MJ/kg of fuel produced, so we're already looking at 100kW of initial power to get the barebones system up and running (after which we can bootstrap the infrastructure, since nearly all payload will reach it's destination). 200kW would be good to aim for. I reckon we could get that into 10 tonnes, which is about what the Falcon Heavy could send to the surface. Given that a Sundancer is only about 10 tonnes as well, I reckon a "Moon Direct" mission could be done in 4 Falcon-H launches, plus a crew launch on a Falcon IX. If that sounds like a lot (total payload to orbit ~2x that of a single Saturn V), remember that it gives you a Lunar base with fuel production capability, and the mission could still be done for under a billion dollars (using off-the-shelf technology).

Anyway. Properly modified (probably with an LH2 tank simply attached to them; perhaps the Kerosene tank could be used for storing water if it can't be modified easily to store Oxygen, or even used as a wet workshop), any upper stages could be added on to the LEO depot until enough fuel has been accumulated for the next stage. Propably the LH2 tanks would be launched seperately, with any excess fuel in the upper stages being used to reach EML1 and Luna. Once we've got enough fuel, the EML1 depot would be launched (or it may be cheaper to use an Ion drive to get it to EML1 over a period of several months to a year - the solar array required could then be used as both a solar shade for the cryogens and a power supply to produce fuel from water delivered to it).

Actually, using Ion drives could significantly change the dynamics of such a scheme... could the Lunar base be delivered in one piece by one? It's something to look at closer, certainly.

I think the crew vehicle could be modified from an existing Dragon reasonably easy. Just give it a cylindrical service module, fuel tanks, and rockets, and launch it fueled on the FH... if we can refuel at the Lagrange point, it needn't have a mass ratio of more than 2.5 I'd think - call it 3 for extra margin (or maybe not - the craft would have to mass under 18 tonnes for a FH launch, and given that it's using hydrogen, that may not be possible, and anyway would give us more capablity than needed, since an optimistic analysis using a delta-V of 3.6km/s and Vex of 4.5km/s gives a mass ratio of 2.23; say a mass ratio of 2.6). Okay, so we may have about 20 tonnes to play around with. An empty Dragon masses 9 tonnes; a full Dragon masses 13 tonnes. Say we need 15 tonnes for the crew compartment (that 4 tonnes is for cargo, and I'm pretty sure people + life support won't come to 4 tonnes). Fuel tanks for LOX/LH2 come to about 15% of their contents, so that's 0.15*40 (it's a very rough calculation)... in total it's 21 tonnes, which given that it's very rough means it should squeeze down to 20 tonnes.

So, crew launch and the Lunar base have come to 5 launches so far. The LEO depot shouldn't be more than a single launch (LH2 tanks will be launched on fuel launches), so that's 6. If we only need another couple of launches for the EML1 depot, then the launch cost could come to ~$640 million. Now comes the real unknown - development costs...


Use what is abundant and build to last

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#8 2011-12-22 05:04:29

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Developing the cis-Lunar economy and infrastructure

Terraformer wrote:

Only if it's abundant enough... bear in mind we need at least around 15MJ/kg of fuel produced, so we're already looking at 100kW of initial power to get the barebones system up and running (after which we can bootstrap the infrastructure, since nearly all payload will reach it's destination). 200kW would be good to aim for. I reckon we could get that into 10 tonnes

Hi Terraformer, Merry christmas by the way.

The Suns energy at the Moon is about 1358 watts a square metre. Our best solar panels tend to give about 25% efficiency that gives a lot of power. One other advantage on the Moon is structural stress due to gravity is a minor issue, structures there can be held up on very thin poles. So if we develop a lander weighing about 5 tonnes that once its solar panels are deployed gives us about 75KW that should be enough to start base operations. We do not need these for shading simply a mesh with attached bags of regolith will be lighter (and cheaper) to install.

If we have a base design of power lander we can simply keep sending these and increasing our bases power supply as we need it. Of course we will also be using an automated system to produce solar cells out of the regolith but these will be a lot less efficient. Still the very large farms we can make out of these and the ability to create mirrors to keep these panels in light will make up for that inefficiency.

The area where we believe there are volatiles tend to be conveniently near the peaks of constant light. These peaks may be very rough but if we can access them we will then have the ability to create constant solar power to our bases.

Last edited by Grypd (2011-12-22 05:06:14)


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#9 2011-12-22 14:08:14

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

Grypd wrote:
Terraformer wrote:

Only if it's abundant enough... bear in mind we need at least around 15MJ/kg of fuel produced, so we're already looking at 100kW of initial power to get the barebones system up and running (after which we can bootstrap the infrastructure, since nearly all payload will reach it's destination). 200kW would be good to aim for. I reckon we could get that into 10 tonnes

Hi Terraformer, Merry christmas by the way.

The Suns energy at the Moon is about 1358 watts a square metre. Our best solar panels tend to give about 25% efficiency that gives a lot of power. One other advantage on the Moon is structural stress due to gravity is a minor issue, structures there can be held up on very thin poles. So if we develop a lander weighing about 5 tonnes that once its solar panels are deployed gives us about 75KW that should be enough to start base operations. We do not need these for shading simply a mesh with attached bags of regolith will be lighter (and cheaper) to install.

If we have a base design of power lander we can simply keep sending these and increasing our bases power supply as we need it. Of course we will also be using an automated system to produce solar cells out of the regolith but these will be a lot less efficient. Still the very large farms we can make out of these and the ability to create mirrors to keep these panels in light will make up for that inefficiency.

The area where we believe there are volatiles tend to be conveniently near the peaks of constant light. These peaks may be very rough but if we can access them we will then have the ability to create constant solar power to our bases.

The PV panels used by NASA are now on about 40% efficiency. Cost is of little concern in comparison to the overall mission cost.

Another point - as there is no weather on the Moon, I see no reason why thin film just can't be laid on rocky parts of the Moon - no need to encapsulate it and add mass that way.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#10 2011-12-22 14:40:15

Terraformer
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From: The Fortunate Isles
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Re: Developing the cis-Lunar economy and infrastructure

For the same reason we don't use inflatable solar panels on space stations and the like - atmospheric dust (though I dread to think about the dust that the panels would attract elecrostatically...) isn't the only problem. There's also radiation damage, which is normally dealt with by the atmosphere...

At the poles, you can't just lay the solar cells out, you have to hang them on something to get the sunlight.


Use what is abundant and build to last

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#11 2011-12-22 15:49:44

louis
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From: UK
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Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

Terraformer wrote:

For the same reason we don't use inflatable solar panels on space stations and the like - atmospheric dust (though I dread to think about the dust that the panels would attract elecrostatically...) isn't the only problem. There's also radiation damage, which is normally dealt with by the atmosphere...

At the poles, you can't just lay the solar cells out, you have to hang them on something to get the sunlight.

Have you got any citation for that?  Radiation damage is not going to be affected by encapsulation is it? But maybe I am wrong...? 

I don't see any problem with stretching the PV film  between bolts drilled into the mountainsides, with tensors pulling the film tight.   

There may be some loss of function from dust damage, but I think it will be slight.  Or rather, I await evidence to the contrary.


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#12 2011-12-22 17:19:29

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Developing the cis-Lunar economy and infrastructure

One of the single greatest advantages of the Moon is the very strong sunlight, but without an atmosphere or strong magnetic field we will get hit by very strong flux fields. Our best solar panels also tend to have less resistance to all that they will face and a long constant life is much more preferable than a short very active life.

On the Moon we can make solar panels that though guite inefficient by what the standards we use the simple amount of energy available and the very cheap method of manufacture makes them the best choice on the Moon. It is this ability to keep growing the energy supply without needing major supply from the Earth that will develop the lunar economy.

But just laying them flat on the ground invites them to be covered in dust and also to be in shade. Simple local manufactured A frames resting boards of these solar panels makes there connection to the electrical grid and general maintenance easier.


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#13 2011-12-22 17:31:57

louis
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From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

Grypd wrote:

One of the single greatest advantages of the Moon is the very strong sunlight, but without an atmosphere or strong magnetic field we will get hit by very strong flux fields. Our best solar panels also tend to have less resistance to all that they will face and a long constant life is much more preferable than a short very active life.

On the Moon we can make solar panels that though guite inefficient by what the standards we use the simple amount of energy available and the very cheap method of manufacture makes them the best choice on the Moon. It is this ability to keep growing the energy supply without needing major supply from the Earth that will develop the lunar economy.

But just laying them flat on the ground invites them to be covered in dust and also to be in shade. Simple local manufactured A frames resting boards of these solar panels makes there connection to the electrical grid and general maintenance easier.

I couldn't disagree more.  Energy generation is the one great advantage we have in solar system exploration; the problem of mass is our one great disadvantage.  It therefore pays in the initial stages to run with the most efficient system in terms of both conversion and energy density (as long as it delivers on reliability and flexibility of course).

I agree the aim should always be to begin developing ISRU energy asap but I am not sure manufacturing PV panels will be that easy, as opposed to manufacturing metal reflectors and steam boilers (or Sterling engines).

I never suggested laying the PV film "flat" in the shade to pick up dust kicked up by colonists!!  I think we would be laying the film out on rocky hillsides using bolts to fasten the film (under tension).
What's wrong with that. There will be a huge mass saving. Doesn't matter if it only lasts 5 years.


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#14 2011-12-22 17:58:14

Terraformer
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Re: Developing the cis-Lunar economy and infrastructure

You only want to base to last 5 years? We need to keep growing our power supply, and, at least in the beginning, ISRU power is going to be difficult.

BTW, here's a link about radiation damage - http://www.soton.ac.uk/~solar/cells/spacesolarcells.htm

Louis, at the poles sunlight shines almost horizontally. It's basically a sunset which never manages to set, instead moving around the horizon. The solar panels are going to have to be straight up almost, as well as rotating to catch the light. That's no show stopper, far from it - a regolith filled base and inflated framed would mass quite low and allow the solar panels to be suspended quite high off the surface, and rotate. But I don't know how much mass we'll be looking at for our power, and numbers like that are what I'm interested in.

Remember, the first export is going to be fuel. It's best to not get ahead of ourselves when it comes to developing Luna. Later missions are going to bring along what we need to industrialise (incidentally, I reckon you'd only need 4-5 flights of FH, if you had copious amounts of Lunar fuel, to set up a colony AND mine Phobos for fuel).

I'm not daunted by the technical problems. It's the OST that gets in the way... I can just imagine some greedy little country suing for a cut of the profits, and an international court awarding it to them. I suppose the only way to get around that is to do what they did in Fallen Angels, and declare independence if and when that happens, regardless of readiness.


Use what is abundant and build to last

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#15 2011-12-22 18:23:49

louis
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From: UK
Registered: 2008-03-24
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Re: Developing the cis-Lunar economy and infrastructure

Terraformer wrote:

You only want to base to last 5 years? We need to keep growing our power supply, and, at least in the beginning, ISRU power is going to be difficult.

BTW, here's a link about radiation damage - http://www.soton.ac.uk/~solar/cells/spacesolarcells.htm

Louis, at the poles sunlight shines almost horizontally. It's basically a sunset which never manages to set, instead moving around the horizon. The solar panels are going to have to be straight up almost, as well as rotating to catch the light. That's no show stopper, far from it - a regolith filled base and inflated framed would mass quite low and allow the solar panels to be suspended quite high off the surface, and rotate. But I don't know how much mass we'll be looking at for our power, and numbers like that are what I'm interested in.

Remember, the first export is going to be fuel. It's best to not get ahead of ourselves when it comes to developing Luna. Later missions are going to bring along what we need to industrialise (incidentally, I reckon you'd only need 4-5 flights of FH, if you had copious amounts of Lunar fuel, to set up a colony AND mine Phobos for fuel).

I'm not daunted by the technical problems. It's the OST that gets in the way... I can just imagine some greedy little country suing for a cut of the profits, and an international court awarding it to them. I suppose the only way to get around that is to do what they did in Fallen Angels, and declare independence if and when that happens, regardless of readiness.

No, I want to maximise the industrial infrastructure from day one. The way to do that is to get the most efficient energy infrastructure up there from the beginning.   I don't deny there is radiation damage, but obviously one needs to balance a number of desired outcomes: efficiency, low mass, long lifetime. I don't think any of us have got all the necessary facts to hand, but clearly the greatest needed for imported energy facilities is in the early stage of the colony, so I think long lifetime is less important than efficiency and low mass.

If you are taking the equipment to track the sun with your PV panels, you are adding a huge, huge mass burden.  Why bother - there will be plenty of very steep inclines which will be perfect for PV film. With enough film you can cover all angles.

What's OST??


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#16 2011-12-23 03:53:15

Terraformer
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From: The Fortunate Isles
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Re: Developing the cis-Lunar economy and infrastructure

Outer Space Treaty.

Tracking the sun at the Peaks of Eternal Light will not add much mass burden, as the sun travels in a known circuit - all you need is an electric motor to rotate the wall of solar cells.

Why are you so sure there will be near vertical inclines?

The critical thing at the beginning - which is what I'm talking about - is to get the basic fuel infrastructure set up, after which importing everything else becomes much easier (i.e. a Falcon Heavy can throw all 53 tonnes of it's'payload at Lunar, rather than about 13 tonnes). What I wanted to discuss was that initial stage.


Use what is abundant and build to last

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#17 2011-12-23 05:08:13

Grypd
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Posts: 1,879

Re: Developing the cis-Lunar economy and infrastructure

louis wrote:

I couldn't disagree more.  Energy generation is the one great advantage we have in solar system exploration; the problem of mass is our one great disadvantage.  It therefore pays in the initial stages to run with the most efficient system in terms of both conversion and energy density (as long as it delivers on reliability and flexibility of course).

NASA has developed what are called Multi Junction cells these are the super efficient ones with reports of up to 43.5% efficiency. But the solar cells we aim to make in situ are called crystalline silicon. They are not only much tougher they require no materials from Earth. You state the problem of Mass is our biggest problem you are correct that is why the ability to make them on the Moon is critical. The fact that these can be made by an automated process and we can replace them as they wear out is super critical. We are likely to have the ability to produce during daylight hours much more power than we really need and as we expand so can our energy grid.

I agree the aim should always be to begin developing ISRU energy asap but I am not sure manufacturing PV panels will be that easy, as opposed to manufacturing metal reflectors and steam boilers (or Sterling engines).

We have already tested and made these cells here on the Earth in a lunar simulated enviroment. The process is actually very simple. Putting these cells which resemble tiles onto a panel is again simple. The panel is made of lunar regolith it is made of silica the base element of the Moon and quickly heated creating lunar fibreglass.

Metal reflectors on the Moon should be a relatively easy process to make but a steam boiler on the Moon not so easy at all.

I never suggested laying the PV film "flat" in the shade to pick up dust kicked up by colonists!!  I think we would be laying the film out on rocky hillsides using bolts to fasten the film (under tension).
What's wrong with that. There will be a huge mass saving. Doesn't matter if it only lasts 5 years.

What we know of the Moons geography is limited. What we have found so far is that the Moon is made of regolith, the upper foot to a couple of feet in depth has been loose. After that it is seriously compacted regolith but still not a solid. We have yet to see solid rock. Those peaks we are seeing will likely be the same. The edges will be the equivalent of scree slopes of broken and jagged material and it may be that they will have the constituency of slag heaps. They will also tend to point the wrong way for the sun most of the time. A solar cell farm sitting on A frames will be facing the sun as it traverses the sky all the time.


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#18 2011-12-23 05:19:26

Terraformer
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Re: Developing the cis-Lunar economy and infrastructure

Hmmm... these ISRU solar panels sound good, do you have a link? If we can produce them on Lunar with no imports, perhaps we'll be able to produce them elsewhere...

Certainly, the ability to easily expand our energy base will be a great benefit to our fledgling Lunar city, allowing energy intensive activities (such as smelting Aluminum) to be undertaken.

The question is, what does our industrial seed mass in at?


Use what is abundant and build to last

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#19 2011-12-23 06:02:58

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Developing the cis-Lunar economy and infrastructure

Certainly but it is a copy of an old new scientist from 11 years ago. The proposals have been around that long. Japanese comapnies even want to turn the whole Moon into a power station to beam microwave power back to the Earth.

New Scientist: Lunar power

The University of Houston proposed the idea and even went so far as to testing it in a vacuum chamber. We would simply ignore the first stage and put a full refinery onto the Moon as one of the first things we did.

The question is, what does our industrial seed mass in at?

That is the question we need to be able to send enough capacity to be able to tool up our operations on the Moon.

So just what will we need to send. Some form of brick maker to create structures that we can put our industrial capacity in to protect it from the massive changes in tempatures on the Moon. The ability to actually harvest regolith and to break its properties down and to then seperate metals and volatiles apart. Some means to develop more harvesting and construction capacity the list goes on.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#20 2011-12-23 18:14:06

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

Grypd wrote:

Certainly but it is a copy of an old new scientist from 11 years ago. The proposals have been around that long. Japanese comapnies even want to turn the whole Moon into a power station to beam microwave power back to the Earth.

New Scientist: Lunar power

The University of Houston proposed the idea and even went so far as to testing it in a vacuum chamber. We would simply ignore the first stage and put a full refinery onto the Moon as one of the first things we did.

The question is, what does our industrial seed mass in at?

That is the question we need to be able to send enough capacity to be able to tool up our operations on the Moon.

So just what will we need to send. Some form of brick maker to create structures that we can put our industrial capacity in to protect it from the massive changes in tempatures on the Moon. The ability to actually harvest regolith and to break its properties down and to then seperate metals and volatiles apart. Some means to develop more harvesting and construction capacity the list goes on.

There is no reference in your link to the rover having been built or the process having been trialled in a simulated lunar environment, which I thought was your claim. I don't think anyone has yet demonstrated this as feasible.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#21 2011-12-23 20:46:41

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,433

Re: Developing the cis-Lunar economy and infrastructure

Lunar insitu materials used to make solar cells...

http://sbir.nasa.gov/SBIR/abstracts/05/ … SBIR_05_P1

http://www.macrovu.com/image/PVT/NASA/R … lrC.v3.pdf

http://www.sspi.gatech.edu/insitu_resources.pdf

The power incident on the Moon from the Sun is 1.36 kW/m2. Even with a solar cell of
10% efficiency ( <_ typical terrestrial), significant power could be generated on the Moon
(1 square kilometer ~ 1.36 gigawatts).

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#22 2011-12-24 00:27:14

JoshNH4H
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From: Pullman, WA
Registered: 2007-07-15
Posts: 2,564
Website

Re: Developing the cis-Lunar economy and infrastructure

There's been a lot of activity here over the last few days.  Anyway, with regards to lunar infrastructure:  My thoughts are that in the short term it's going to be a place to make fuel, and in the long term it'll be a place to make ships.  Or at least, it'll be a place to get mass to do all of those things with; Just because the Moon is being used to get the mass doesn't necessarily mean that it's the best place to process it. 

Before I go there, though, I want to mention something that should be number one on everyone's wish list for the Moon (Or Phobos, or both):  A fuel-less launcher.  If we're using the Moon primarily to make fuel, it's incredibly wasteful, both in terms of energy and production capacity to burn half of it (or potentially more, depending on the fuel) just getting there.  It doesn't make anything impossible or not viable as Zubrin has said, but it does make it less cost-effective.  A railgun with a connection between the rails and the payload made of plasma would be very energy efficient and pretty simple to build.  You could conceivably get away with one that was a kilometer long (acceleration would be very high, as would power consumption, but the potential benefits are astronomical, if you'll pardon the pun).  You could make the rails out of iron or aluminium, and incorporate the plasma generator into the device.

Anyway, there is also the possibility of processing the fuel in Earth Orbit as opposed to processing it on the Moon.  This lets you process it where you want to use it, in the relatively energy-rich and on-the-way environment of GEO.

Here's another really wacky idea: Process your fuel in GEO using power transmitted from Earth.  After all, at this point space-based power generation is less than economical.  Therefore, power would be cheaper if gotten from Earth.  Instead of beaming it down from GEO, beam it up from (say) a dedicated nuclear reactor 36000 km below.  Use that to split raw materials.  Use ion tugs (or, more exotically, a vehicle with a long tether that uses the Earth's magnetic field to move) to ferry the fuel down to a depot in LEO, and then to come back up for reuse.  This reduces the stress on a distant Moon base.  What does everyone think?  This would reduce initial transport costs to the Moon, and future transport costs to and from Earth.  This kind of approach makes more sense (I think) when you're looking to use the Moon as a fuel depot and materials source as opposed to trying to colonize it.  It also makes it possible for NEOs and Martian satellites to compete for revenue in terms of providing fuel, which will potentially lower prices as well as give a kickstart to new colonization enterprises.


-Josh

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#23 2011-12-24 00:39:46

Adaptation
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Registered: 2011-11-22
Posts: 42

Re: Developing the cis-Lunar economy and infrastructure

I like solar and it certainly has its place but there is a better solution for lunar mining and that is nuclear.  More than 50 years ago they where able to put reactors in submarines I'm sure we can manage to get one on the moon if we wanted to.   

The first lunar export will be entertainment flowed by normal lunar rocks going to collectors and enthusiasts.  I am skeptical about the demand for fuel early on but there is another valuable resource.  Apollo core samples detected drastically lower gold in the first little bit of regolith than in deeper areas.  LCROSS detected extremely elevated gold and mercury levels in cold craters.  Mercury makes sense for obvious reasons but gold dust is though to electrostatically propel itself after being struck by micro meters but the static is generated by sunlight so it migrates to the colder areas with the water and mercury. 

I think either platinum mined from asteroid impact zones or gold mined from cold traps should be explored for early utilization.  They come with a sure market ready to tap.

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#24 2011-12-24 06:26:56

louis
Member
From: UK
Registered: 2008-03-24
Posts: 7,208

Re: Developing the cis-Lunar economy and infrastructure

SpaceNut wrote:

Lunar insitu materials used to make solar cells...

http://sbir.nasa.gov/SBIR/abstracts/05/ … SBIR_05_P1

http://www.macrovu.com/image/PVT/NASA/R … lrC.v3.pdf

http://www.sspi.gatech.edu/insitu_resources.pdf

The power incident on the Moon from the Sun is 1.36 kW/m2. Even with a solar cell of
10% efficiency ( <_ typical terrestrial), significant power could be generated on the Moon
(1 square kilometer ~ 1.36 gigawatts).


Those are all proposals and they haven't got to grips yet with the key issues of deposition - which on earth seems a pretty sophisticated process requiring sterile conditions.

I am all in favour of developing automated robotic mining, but it will be a tricky business. 

The moon we should not forget is very close to the Earth.  If it's lunar tourist industry can pay for imported PV Panels, I am not sure the effort of ISRU is necessarily worth it. It's not the same situation as on Mars where I think the argument for ISRU is much stronger. The experience with tourism on Earth suggests that tourism centres, like say the Caribbean, simply import the more sophisticated technology.

I think for the Moon I would recommend a slower path to ISRU.

The main focus should be on getting lots of people to the Moon, building up permanent settlements.


Let's Go to Mars...Google on: Fast Track to Mars blogspot.com

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#25 2011-12-24 07:21:06

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Developing the cis-Lunar economy and infrastructure

louis wrote:

Those are all proposals and they haven't got to grips yet with the key issues of deposition - which on earth seems a pretty sophisticated process requiring sterile conditions.

I am all in favour of developing automated robotic mining, but it will be a tricky business.

As sophisticated as making LEDs the answer is yes we mass manufacture these with little human interaction. The panels are easier to make. They need a vacuum and that we can provide reasonably easy on the Moon and of course the materials.

The moon we should not forget is very close to the Earth.  If it's lunar tourist industry can pay for imported PV Panels, I am not sure the effort of ISRU is necessarily worth it. It's not the same situation as on Mars where I think the argument for ISRU is much stronger. The experience with tourism on Earth suggests that tourism centres, like say the Caribbean, simply import the more sophisticated technology.

The less we have to send the less it costs to go to the Moon and as such the more people who go and the more that comes with the Tourists. This is a very less equals more situation.

I think for the Moon I would recommend a slower path to ISRU.

The main focus should be on getting lots of people to the Moon, building up permanent settlements.

I agree that more people are needed and ISRU is essential to allow this to happen. What are these people going to breathe what are they going to live in. If we can reduce costs then we can send more people. If you cannot reduce the costs then it is highly likely there will be no Moon missions beyond flags and footprints.

Last edited by Grypd (2011-12-24 07:22:00)


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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