# Transfer of electricity from The Moon

It's 2020, carbon emissions are in decline but not fast enough. Oceans continue to rise at an increasing rate, so a plan is proposed to cut ALL carbon emissions:

Cover the moon in solar panels (take the center of the moon to be the origin, then the solar panels follow the planes: x=0, y=0, z = 0, where they intersect with the surface of the moon), so that at any given point in time (outside of lunar eclipse) they produce electricity. However there is a problem, how can the electricity be transferred from The Moon, to Earth, where it is needed?

Assume the electricity can be stored for a limited amount of time on both The Moon and Earth, so continuous electricity transfer is preferrable, Ideally efficiency of transfer over 50%, and to be economical for the long term.

• Why are the solar panels going on the Moon, so that they're in the dark for half of the time, and not in Earth orbit where they're much closer to us and they can be in sunlight and generating power nearly all the time? Apr 2, 2017 at 18:47
• Probably because they're going to be made in-place, using lunar resources, instead of making them here on Earth or the Moon and sending all that mass to orbit. The moon's gravity well is lower, but then you have mine the resources for the panels, AND the rockets AND the fuel. Apr 3, 2017 at 9:02

There are actual plans to collect solar energy from space and transfer it to Earth. I recommend reading about Space Based Solar Power, or SBSP for brevity.

The moon would not be the best choice for a collection base because A) eclipses and B) you'd not use more than half of its surface for collection at any given time, with most of your collecting surfaces at bad angles. You'd get more value for your money by having all those surfaces in space, orbiting the Earth, so that they can aim their panels at the sun.

As for the transfer proper, just have each satellite aim a tight beam of microwaves at the Earth and collect it with huge dishes. Microwaves can get into the atmosphere with little loss. An depending on the power setting they should collectively give enough energy that the dishes on Earth can power whole cities, but people hit by the beam will be receiving less radiation than they already do from their cell phones ans routers.

The Simcity series of games has had this kind of power generation ever since Simcity 2000. It was always one of my favorite power plants.

• im confused as to how the microwaves are transferred back into electricity, could you explain? Apr 2, 2017 at 19:27
• @Cursed1701 I'm no expert in this kind of thing, but I imagine the microwaves would excite water molecules, turning them into steam, which in turn turn a turbine. Apr 2, 2017 at 19:58
• Wow. Why are we not funding this. Apr 2, 2017 at 20:19
• @Cursed1701 microwave and visible light are two kinds of electromagnetic radiation. You can convert both into electricity directly. But you can also use MW as you said. Some solar power plants use that principle too, to heat water in a tower. Apr 3, 2017 at 2:10
• @Maurycy Japan's space agency had a project to make that real like a decade ago. I don't know what became of that, but I am going to check it out. Apr 3, 2017 at 2:11

The common solution for power transmission in space is microwave power transmission:

https://en.wikipedia.org/wiki/Microwave_transmission#Microwave_power_transmission

It is not perfect, but quite efficient. Since they want continous power, they would need three relay satellites on geostationary orbit, spaced 120 degrees apart (on of them will be always in line of sight with Luna, and they will always see each other.), to recieve the microwaves, and beam them down to the planetary surface.

There are problems, of course: these systems will have magnitudes higher power and range than current devices, airplanes have to avoid the beams, waste heat is to be radiated away from the relay satellites, regular maintenance is needed...

But nothing unsolvable for a civilization, which is able to cover the Moon with solar panels.

You could use the electricity on the moon to mine and refine helium-3.

http://www.popularmechanics.com/space/moon-mars/a235/1283056/

Helium-3 is hard to get on earth but it is present on the moon,. in surface dirt. I was wondering why it would not float away but of course helium would not be buoyant on the moon. In the linked article it states that available helium-3 would make fusion power safer and easier. Fusion power is what we need.

1: Use the solar energy to massively mine moon for helium-3. Worry very little about environmental impact.

2: Concentrate helium-3 into cylinders.

3: Launch cylinders back to earth with a (solar-powered!) electromagnetic mass driver.

4: Use helium-3 to make safe fusion power plants.

5: Power flying Delorean (flown by myself) with one such device. Cursed1701 I will let you borrow it to impress your date.

I see in looking for a source for the mass driver (as described in Heinlein's Moon is a Harsh Mistress) that the helium mining scheme exactly as I describe here was done in a movie called Moon - a movie I had not heard of but which I now intend to watch.