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Japanese Firm Proposes Microwave-Linked Solar Plant On the Moon
littlesparkvt writes "Harnessing the sun's power is nothing new on Earth, but if a Japanese company has its way, it will build a solar strip across the 11,000 mile Lunar equator that could supply our world with clean and unlimited solar energy for generations." Some of the company's other projects look just as ambitious.
The Lunar equator is 11,000 Kilometers long.
"I do not agree with what you say, but I will defend to the death your right to say it"
Collect massive amounts of power, and beam it towards a planet. What could possibly go wrong?
In a surprise vote at the UN, the General Assembly accepted a proposal from Krasnovia to rename the planet. The new name is "Alderaan."
much of left-wing thought is a kind of playing with fire by people who don't even know that fire is hot - George Orwell
s/Timely/oldAsFuck/. Hilarious when Huffington Post beats Slashdot to a story by two and a half months.
I am Audience.
Solar insolation on the moon is not dramatically higher than on Earth - around 1400 W/m^2 versus around 1000 W/m^2 on Earth. Granted, a Lunar solar station wouldn't be affected by weather, but Earth based receivers will suffer from efficiency loss during bad weather.
Could they achieve the same result by building a bit larger system on earth, but without the hundreds (or thousands?) of rocket launches it would take to get the materials to the moon to get the thing started?
Besides, who wants to see a big black ribbon around the moon?
I remember having this conversation in Physics class many years ago, would be fantastic if it goes ahead but I honestly don't think that anyone would invest the huge amount of money needed to even attempt this, at least not until the oil has run out.
In a cybernetic fit of rage she pissed off to another age...
A major issue is that the moon is fairly far up Earth's gravity well. It is easy to get things to low-Earth orbit and already tough to get things to even geo-stationary. The main saving of putting anything on the moon will come if you can do a large part of your construction on-site since otherwise moving that much material up is going to be tough. If you are doing automated construction on site you also are going to need to be able to make mainly a lot of solar cells. Solar cells are primarily silicon and there's already been prior research on refining the moon's regolith for silicon to manufacture electronic components and that looks possibly doable but one does need to get over some technical chemistry issues. See e.g. http://www.asi.org/adb/02/13/02/silicon-production.html.
The other issue is distance for power transmission: most designs for microwave power involve power transmission from at most a little over geo-stat at about 35,000 km. The distance to the moon is about 10 times that, so if you don't have a really tight beam, there are going to be issues. Also, since the moon change's position you are going to need a large number of sites on Earth that can receive the beam, and if you can't switch off smoothly between them always (which would itself require massive planet-wide infrastructure), you would still need power sources on Earth (possibly just massive storage facilities?) to deal with those times.
Overall, a really cool idea with a lot of technical hurdles. I hope they can make it work but I'm not optimistic.
Some of the company's other projects look just as ludicrous.
Helps when you put the D in there.
"Don't meddle in the affairs of a patent dragon, for thou art tasty and good with ketchup." ~ohcrapitssteve
Actually the problem is that Earth-based solar collection is terribly inefficient. A solar cell (15 - 20% efficient to begin with), fixed to one spot on the Earth, is exposed to sunlight for a fraction of a day, sunlight which has been diffused by the Earth's atmosphere. Extraplanetary collection is actually a very good idea.
I am Audience.
Simple solution is to turn disasters off.
signature is pants
Helps when you put the D in there.
That's what she said ... heh heh heh
Do you know about moon phases?
After the oil runs out, there won't be any money. Details here. Warning -- it's a harrowing read.
Shimizu Corporation intersects with Dr. Criswell in another way that I just discovered today after searching for his more recent patents.
We've got to attract technological civilization's population away from natural ecosystems into idealized artificial environments such as Shimizu Corporation's design for what it calls the "Green Float". You can house the entire population of civilization in beach-front property on the boundary of a tropical rain forest where people can swim, fish, hunt and gather recreationally, as well as access the height of urban lifestyle. From there space habitats are likely to emerge so that the natural propensity of these "cells" to replicate endlessly needn't destroy Earth's biosphere. Interestingly, I came up with a geometry that looks very similar to that years ago, with the Solar Updraft Tower Algae Biosphere proforma and, over the subsequent years, I found a floating photobioreactor technology that requires little more than 2 layers of polyfilm that has demonstrated production per cost figures far in excess of what I projected in that proforma. Before I ran across Shimizu Corp's Green Float I had further refined the idea based on the Atmospheric Vortex Engine, which, like Shimizu's "Green Float", is ideally sited in the equatorial doldrums and could make use of the central tower of the Green Float. I posted some preliminary thoughts over at the Seastead Institute's blog.
A key problem I attempted to address in my preliminary thoughts was the early market for energy from the Atmospheric Vortex Engines that would form the nuclei for Shimizu's Green Floats. A big problem was the fact that the electric power markets are thousands of miles away from the floating AVEs even if you could build on the order of a terawatt of oceanic power transmission lines thousands of miles long. Early markets are critical for attracting capital -- the lack of which renders such grandiose ideas "non-starters".
I had thought it would be very nice to have a microwave transmission technology that could dynamically switch the power distribution to achieve the holy grail of "dispatchable" power generation for peak loads, but wasn't aware, until just now, that Dr. Criswell's recent revision of his patent serves precisely that purpose.
Seastead this.
It's not the energy we use that does the warming - the CO2 released from burning fossil fuels captures about a million times as much solar energy per year as there was energy in the fuel, and it does so for many decades before leaving the atmosphere.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
Yes, I don't however see any data on their website about how wide they are planning to build the ring out. If their graphical renderings are accurate, they display a 195 pixel moon with a 22 pixel ring. Given that google tells me the moon's radius is 1737 km, that means the ring should be about 200 km wide.
So considering that we have a 11,000 km ring that is 200 km width, the power generation for the light-facing half should be what you'd expect from 5500km x 200km or 1,100,000 square kilometers. I've seen estimates of 1.2 mw per square km for solar. Using that as a basis we'd expect 1,320,000 mw of constant power generation. Wikipedia says to take off 10% due to conversion inefficiencies of microwave transmission of electricity and we probably should take off another 5% or so for weather and atmospheric disruptions or inefficiencies. That leaves us with 1,122,000 mw of constant power.
As a point of comparison, all the wind power in the entire world added up to 238,351 megawatts in 2011, so it is roughly five times the capacity of that. However, in 2008 the world had an average power consumption rate of 15 terawatts . 1,122,000 mw is 1.12 terawatts, so this project could supply roughly 7% of the worlds electricity if it was operational today.
The moon has an area of 37,932,000 square km though, so if we coated the entire moon and got energy from the sunny side and do the same math we get 19.34 terrawats. So, at our current state of energy usage it could power the world if we coated the moon in solar panels.
I'm not sure about the aesthetics of it though, a racing stripe on the moon.
Big apple, new Yorik, undig it, something's unrotting in Edenmark.
this is misdirecting effort. smart people solving a problem that doesn't exist. we use energy we get better we don't need to pump more from the moon.
Sorry, it doesn't work that way. Counter-intuitive I know, but reality is often like that: improvements to energy efficiency paradoxically tend to stimulate further consumption.
..Mullah or Pope, Preacher or Poet, who was it wrote: "Give any one species too much rope and they'll fuck it up"?
On ISS, they get about 0.1 mw from an acre, that is 24.7 mw from km2.
Pedantic remark: There is a slight difference between a mW (milliwatt) and a MW (megawatt), a factor of about a short billion, or 9 (decimal) orders of magnitude.
Even more pedantic: W is upper case (as it's named after James Watt). I'm not aware of any unit using a lower case "w" as the abbreviation. But in general, capitalisation is significant for units.
Stephan
You got your units wrong here, I'm afraid. The source you are referring to is not speaking about 1.2 MW per square km. It is speaking about 1.2 MW per km of road. Roads are pretty thin, so installing solar panels along them does not result in many square kilometers per km.
This mistake leads to your result being off by a huge amount. The solar constant is 1.361 GW per square km. Normally this is reduced by 30% by the atmosphere, but that does not apply in space. Neither are there clouds to worry about, so we can pretty much use this number directly, after dividing by pi to account for the lunar day/night cycle, giving us about 0.45 GW per square km. High-end satellite solar cells get up to 29% efficiency. Using that, we get 0.13 GW per square km. With an area of 11,000 km by 200 km = 2.2 million square km (we have already taken the night into account in our numbers), that results in a total production of 286 TW, which is 19 times the world's current total energy use. Of course, one has to get this energy down to earth somehow too. This seems to have an efficiency of about 85% (possibly squared - unclear). That partially negates the advantage of being outside the atmosphere, but we still end up receiving 206-243 TW.
So no, the main objection to this plan isn't that there wouldn't be enough energy available. It is how much resources would be spent making it. I think one will need some sort of self-replicating solar-cell-producing robot on the moon to avoid this requiring too many launches. But I have not read the tehcnical details of their plan.
The article did not say oil would run out, just affordable oil.
Here is a summary
The problem is not peak oil, but peak affordable oil.
We are already there, the big oil companies have cut back exploration because the cannot make money even at $100/barrel.
High oil prices choke off growth in our economy
With little or no growth, we cannot pay our debts.
As in 2008, unpayable debt will crack our financial system
As not in 2008, the central banks have shot most of their “arrows” and have few left in their quiver.
With a broken financial system, we will have the social chaos that was barely avoided in 2008
Here's the math:
http://matter2energy.wordpress.com/2011/06/21/the-maury-equation/
and:
http://matter2energy.wordpress.com/2012/03/17/the-maury-equation-redux/
The long and short of it is that any soft of SBSP loses about 1/2 of the power during transmission and grid conversion. There's no way around this, it's basic radio physics.
So to make it work in your favour, you need to generation at *least* twice as much energy. And that's assuming your shipping costs are zero.
An SPS in GEO *might* be able to do that. That's because they get about five times as much light as a panel on the earth - day/night, clouds, cosine angles, etc.
But on the moon you have the same sorts of effects as the earth, with the exception of weather. The panels will cycle under the sun as the moon rotates, and spend half their time on the night side.
There is absolutely no way such a system can make up for the losses in transmission. Period. Do the math yourself if you don't believe me.
All is good and all that, except for the energy input required to produce the solar cells.
Assuming we produce the solar cells here, at the bottom of the gravity well, and transport them to the moon - even if we do not include the energy required to transport that much solar cells to the moon - the energy requirement in the production of the solar cells itself would further deplete the fosiil fuels that are left on Planet Earth.
GGP talked about the possibility of coating the entire surface of the moon
Most of the energy would be spent towards keeping the furnaces lit for the crystallization process - the rest is fairly straightforward manufacturing, and each cell by itself weighs about as much as two sheets of paper cut to the equivalent size (and is only about as thick as one sheet of paper). Brittle as hell, though...
Overall, you could launch enough (and facilities) to the Moon to get things started, then manufacture the hell out of them up there. The Moon has more than enough silicon and other needed materials to make high-grade polysilicon, and the lower gravity would make the CZ and wafering processes a *lot* more consistent.
Quo usque tandem abutere, Nimbus, patientia nostra?