News for hackers. Stuff that matters.
Re:Blue Origin manufactured solar cell prototype from lunar ... by ricardobeat on Tuesday February 14, 2023 @02:27PM (#34794634)
Isn’t solar exposure on the moon stronger than earth due to the lack of an atmosphere? Efficiency per sqm might end up being higher.
Re:Blue Origin manufactured solar cell prototype from lunar ... by beakergordon on Tuesday February 14, 2023 @02:46PM (#34794888)
I think the implied comparison was: do we launch panels to the moon or build them in-situ? The increased solar exposure should boost both of these cases by the same percentage, but if the Earth-manufactured panel is (e.g.) 3x as efficient, it might still make more sense to ship them.
Re:Blue Origin manufactured solar cell prototype from lunar ... by dr_orpheus on Tuesday February 14, 2023 @02:49PM (#34794934)
Yep, you get about 36% more sun above the atmosphere. 1361 W/m^2 above the atmosphere vs ~1000 W/m^2 on a clear day [0].

Now you just need to bring big enough batteries to survive 14 days in a row with no sun.

[0] https://en.wikipedia.org/wiki/Solar_irradiance#Irradiance_on...

Re:Blue Origin manufactured solar cell prototype from lunar ... by leidenfrost on Tuesday February 14, 2023 @03:05PM (#34795166)
Considering the fact that you have the entire moon as available surface, you'd rather lift a giant rock with that power and store all the potential gravitational energy as a "battery".

A 10 ton rock, lifted up to 50m high, will store up to 810M Joules at moon gravity

Re:Blue Origin manufactured solar cell prototype from lunar ... by sacred_numbers on Tuesday February 14, 2023 @03:28PM (#34795482)
Unfortunately I think you're off by an order of magnitude. I think it would be 810 Kilojoules, which is approximately equivalent to a 1kg lithium-ion battery. Of course, you could move thousands of rocks up and down a big crater, rather than just one, but it would still be a lot of infrastructure for a fairly small amount of energy storage.
Re:Blue Origin manufactured solar cell prototype from lunar ... by sbierwagen on Tuesday February 14, 2023 @03:31PM (#34795512)
Three orders of magnitude*
Re:Blue Origin manufactured solar cell prototype from lunar ... by sbierwagen on Tuesday February 14, 2023 @03:23PM (#34795425)
>A 10 ton rock, lifted up to 50m high, will store up to 810M Joules at moon gravity

Wrong prefix? I think you meant 810K Joules.

For Earth gravity: 10,000 kg times 9.8 m/s^2 times 50 m = 4.9 megajoules, 1.36 kilowatthours. (Anker sells a 2.04 KWh battery pack for US$1999: https://www.anker.com/products/a1780)

Again, that's for Earth gravity. Lunar gravity: 10,000 kg times 1.62 m/s^2 times 50 m = 0.81 megajoules, 0.225 kilowatthours.

Gravity storage isn't economical on Earth, and it's really not economical on the Moon, where gravity is lighter.

Re:Blue Origin manufactured solar cell prototype from lunar ... by napier on Tuesday February 14, 2023 @03:09PM (#34795239)
No need for reliance on batteries. Just use the solar generated to process regolith yielding plenty of hydrogen and oxygen for energy storage, breathing, rocket fuel and additional component elements.
Re:Blue Origin manufactured solar cell prototype from lunar ... by beefield on Tuesday February 14, 2023 @03:53PM (#34795795)
I think you might find places relatively close each other in the moon polar areas that are in aggregate illuminated most if not all the time.

https://space.stackexchange.com/questions/34025/moon-polar-d...

Re:Blue Origin manufactured solar cell prototype from lunar ... by joemi on Tuesday February 14, 2023 @03:59PM (#34795904)
Wouldn't it be smarter to build on the far side of the moon? Then you don't need to worry about the Earth obscuring the sun at all, right? Or were you referring to some other phenomena?
Re:Blue Origin manufactured solar cell prototype from lunar ... by 867-5309 on Tuesday February 14, 2023 @04:34PM (#34796374)
the moon is tidally locked to the Earth, i.e. it does not rotate about an axis, and takes ~27 days to orbit. therefore around half of those days are in darkness at any given point on its surface, hence the lunar phases
Re:Blue Origin manufactured solar cell prototype from lunar ... by joemi on Tuesday February 14, 2023 @05:20PM (#34797017)
Ah yeah, makes sense... I confused myself.
Re:Blue Origin manufactured solar cell prototype from lunar ... by outworlder on Tuesday February 14, 2023 @04:12PM (#34796055)
You still get the Moon obscuring itself. The Earth is not eclipsing the Sun most of the time.
Re:Blue Origin manufactured solar cell prototype from lunar ... by oscillonoscope on Tuesday February 14, 2023 @06:45PM (#34797905)
The alternative is that you could also just plan around the lunar cycle by turning machinery off during the lunar night and only having moon landings during the day.
Re:Blue Origin manufactured solar cell prototype from lunar ... by cperciva on Tuesday February 14, 2023 @09:38PM (#34799328)
You still need heaters, because a lot of equipment -- including solar panels -- won't survive thermal cycling otherwise.
Re:Blue Origin manufactured solar cell prototype from lunar ... by midoridensha on Wednesday February 15, 2023 @01:42AM (#34800815)
There are a bunch of things that are better about the Moon: - no atmosphere in the way - no weather or clouds in the way - no buildings or other stuff competing for the land area (yet)

There's no shortage of places to put solar panels, and nothing that will reduce the amount of light getting to them (except the rotation of the Moon itself), so actual efficiency isn't that important.