On Friday, in a blog post that wasn't promoted by press release or Twitter announcement, Blue Origin quietly said its "Blue Alchemist" program has made both solar cells and the wires to transmit their electricity from simulated lunar soil made to be chemically and mineralogically equivalent to lunar regolith. The blog post opens with a photo of a working solar cell, made by their prototype hardware, and below that photo says,
Since 2021, Blue Origin has been making solar cells and transmission wire from regolith simulants.
Making self-sustaining lunar colonies has been talked about for decades. All of the key ingredients for solar cells are present in the rocky and dusty regolith on the surface of the Moon—silicon, iron, magnesium, aluminum, and more. While this particular announcement doesn't talk about many details, they include a conceptual illustration that implies a machine is envisioned that could manufacture large solar panels in one continuous process, practically making a wall or paving the lunar surface around labs or colonies with solar cells. This image shows what I interpret as one of these Blue Alchemist modules seeming to produce a wall of solar cells. Blue claims the lunar factories can scale indefinitely, eliminating power as a constraint anywhere on the Moon.
"Once demonstrated and implemented on the Moon, Blue Alchemist will put unlimited solar power wherever we need it." Blue Origin image.
Solar power in, solar power generation out.
How can it work? Like all metal extraction from ores that many of you are familiar with, the first step is that the regolith has to be melted into flowing rock and then the molten rock has to have the elements separated out, which Blue Alchemist apparently does by changing the melt temperature while electric currents push the metals to the desired electrode to be collected, in a process called "molten regolith electrolysis."
We start by making regolith simulants that are chemically and mineralogically equivalent to lunar regolith, accounting for representative lunar variability in grain size and bulk chemistry. This ensures our starting material is as realistic as possible, and not just a mixture of lunar-relevant oxides. We have developed and qualified an efficient, scalable, and contactless process for melting and moving molten regolith that is robust to natural variations in regolith properties on the Moon.
Using regolith simulants, our reactor produces iron, silicon, and aluminum through molten regolith electrolysis, in which an electrical current separates those elements from the oxygen to which they are bound. Oxygen for propulsion and life support is a byproduct.
It seems there must be some sort of physical separation as well and each of the materials that go into making photovoltaic solar cells must be processed beyond this. Silicon crystal growing is a mature industry and I'm sure much can be learned from veterans of that industry. They note that they purify the silicon crystals to 99.999% pure, necessary for solar cells. Maybe even more so than on Earth, the finished solar cells need to be coated with a layer of glass to protect them from solar wind particles and other harsh aspects of the lunar environment (yes, the elements to make glass are in the regolith, too). Their solar cells are capped with glass and have life expectancy stated as 10 years. The result:
A working solar cell produced by their Blue Alchemist processes. Blue Origin photo.
Blue Origin is apparently going to attempt to market the technology to NASA for use by its
Artemis program to return humans to the Moon in a "sustainable" way. One of the mission statement-like quotes we hear from NASA about Artemis "returning to the moon to stay," presumably to differentiate Artemis from
the Apollo program. This technology could absolutely help enable longer missions by improving the conditions for long stays on the moon.
"Although our vision is technically ambitious, our technology is real now," the company said in its blog post. "Blue Origin’s goal of producing solar power using only lunar resources is aligned with NASA’s highest priority Moon-to-Mars infrastructure development objective."
An important big step toward stepping off the home planet.
EDIT 02/14/23 10:35PM EST: Left out the bold-faced word in the sentence about glass coating solar cells: "...need to be coated..."
That would be awesome, with some hope it may like so much of Space Exploration efforts something useful for Earth.
ReplyDeleteCheaper solar cells maybe?
As usual, this is also the kind of news that leaves one salivating for more details. For instance, that little bit about melting the regolith - how much power is used? What kind of energy inputs are used to produce what power level of cells?
ReplyDelete" . . . that little bit about melting the regolith . . ." Hahahahahahaha! It's only a small detail and nothing to worry about. Neither is the time to manufacture enough components to really power anything. Just small details such as: Just how hot does it have to be to melt and form the product in the moon's vacuum?
DeleteDave
I think most of us have seen enough solar panels to look at that example solar cell and be struck by how small it is. The fact they can do it in a remotely operating little factory like that is the only cool part. Put in lunar "top soil" and get out solar cells. Cool!
DeleteHow hot it has to get depends on which element they're taking out. Aluminum melts out at pretty low temperatures, 660C, compared to silicon at 1410C. A periodic table of the elements with melting points is easier to find than what metals are in that lunar regolith and information on how they can get it out.
I'm probably assuming stuff about how it operates, which is always dangerous.
As others have mentioned, we know it runs on solar power, but we have no data on how much power it needs (besides saying "butt loads") and we (conveniently) have no idea of the size or cost of this machine. What if it would be cheaper to send solar panels up on their New Glenn than run this Alchemist thing?
Yep can be done but it has to be one of the most energy inefficient processes I have ever seen. The melting of the regolith in and of itself is a monster. Then the electrowinning of the individual elements is another biggie. I hope they use a mirror array to do some of the melting. Interesting idea, wish I could be involved.
ReplyDeleteof individual elements is
Sounds excellent. Just what all the sci-fi writers have been writing about since, oh, at least as early as Heinlein.
ReplyDeleteBut...
This. This is Blue Origins we're talking about. How much of this is real and how much is Hopium? Humbug? Hookum?
How big or small is the processing system? How much power is needed? Will it work in a low gravity environment? Can the lab unit be scaled up?
To Bean's comment, it is exactly the sort of thing Heinlein and Pournelle wrote about. So I am a little excited. But given the nature of announcements these days, also waiting for the "correction and clarification" follow up later.
ReplyDeleteAnother question is how hot can the resulting cell be operated? On Earth, where the sun moves fast and cells are cheap, we use 1-sun illumination, lots of cell area, and no tracking. On the Moon, where the sun doesn't move so fast and cells are expensive, the system cost equation might suggest using mirrors and 10 to 50 suns illumination level on fewer cells.
ReplyDeleteIf the can make aluminum, they can make cheap mirrors out of foil. You don't have to worry about corrosion in a vacuum.