The future of mankind

Sunour

After reading the various links you provided and particularly the additional info at
http://www.spaceislandgroup.com/solarsat.html
I place this idea somewhere between very �forward looking statements� and outright science fiction.

Think about the statement beaming the power to earth on a �weak microwave beam�.
You know that �watts is watts�. So, it is either a very strong microwave beam, or a powerful electric charge riding down the pilot wire of the weaker microwave beam,  essentially a continuous lightning bolt.  There would be tremendous concerns about this that need to be addressed.  I want to see their Draft EIR on this one. I think when it hits the streets, it will be shot down in flames.
And despite their �the technology exists� statements,  no one has ever transmitted hundreds of megawatts of power over a thousand miles, much less 22 thousand, by a method similar to this.

They are also going to have extreme difficulties in keeping the solar panel aligned to the sun. Unlike communications satellites which stay oriented to the earth throughout the orbit and focus their smaller and lighter panels towards the sun, these panels are going to have to rotate once every 24 hours so that they stay oriented towards the sun. Without a giant heavy mass in the center, that is going to be extremely hard to do.

I also question their statement that the power will be available 24/7.  Although this is true near the winter and summer solstices, I do not believe it to be possible near the spring and fall equinoxes.  The unit would have to pass through the earths shadow, or �night time�.

The biggest obstacle that they face is their economics. Every ounce that you lift into space costs you big money.  While some of their ideas (e.g. building space stations from expended external fuel tanks) may have some perhaps mutually beneficial ideas, eventually you will run up against the barrier of subsidizing a commercial enterprise with tax dollars. When you combine the costs of this giant solar panel with the costs of lifting it into space, I do not see them doing it cheaper than a bunch of panels (or any other technology we can name) here on earth.  The �gravity well� is a huge obstacle.  

Bottom line, in my opinion, the roll out date on this is not going to be 2012. It would more likely be closer to 2112, and most likely, never.  

I agree... who needs all this power??  But... hey, we're all talking here over powered internet connections... I guess we need *some* power.

I want to comment on two things that have come up in this string.  First, microwave (ovens).  I've been told, supposedly from a reliable source, that the USA is the only country in the world that allows the use of these ovens, and that the microwaves might be having an effect on basic amino acids in foods, such that these become cancer-causing agents.... anyone know anything more about this?  Whether or not it's true, I don't like the idea of being bathed in microwaves from space for the rest of my life!

Secondly, the magnifying glass and the insect... great idea!  Why doesn't someone focus his/her brain on focusing what sun-light *is* available at any given time, on a better (higher-power-density-capable) type of solar collector?  Basically... turn acres of huge flat panels into much smaller areas of collectors under dedicated magnifying glasses?  Totally passive... huge potential for any solar energy collection system.  Maybe the Hubble should be turned around... 180.  NOT!

Microwave ovens are really all around the world and not outlawed, so I doubt that some (Esoteric ?) sources are really  right with the negative effect on food.
But to make you a little nervous: you are daily showered in all kind of 'electro smog' on all frequences emitted from radio & TV stations, radar, cellphones (very near to your brain), microwave links for phone and data transfer, strong electro magnetic fields of high voltage overland lines etc, and they harm you more than warming up food in the microwave oven....

I also see the story of satelite based Solar modules in TV back in March, however the transmission was based on Laser and some science labs are working on receiving/extracting electricity back from Laser beams.
As space technologie is very expensive setting up PV modules on every roof of a building, or huge arrays in the desert might be much more cost efficient than space based PV.

Increasing the poor performance of solar modules & hydrogen fuel-cells might also be a way. Current multi-crystaline modules work at 12-15%, single-C at 16-18% and thinfilm was working at 7-8% (now Shell-Solar made some breakthru for 12-14%). So an Array of 1 square meter catching 1000W of sunlight produces only 120-180 Watt. Some guys also working on this refelction problem so output per space might increase some day.
Fuel cells are also operating on a poor below 20% output, as most energy is lost as heat inbetween the electrolyte layers. Also a lab in Germany is working on improving it and they could made the layer surface so smooth it increased the ratio to more than 50%. Current day technologie (one of the best I see so far) was an electrolyzer with hyrdid storage plus fuelcell combination unit in the internet: input 3800W to produce 12kg/h Hydrogen to store it, and the fuel cell was producing 3KW using 60kg/h.
Now my calculation: To generate 3KWH from the fuel cell, I would need 60kg Hydrogen, prodcued in the electrolyzer 5h long consuming 3.8KW = 19KWH from PV modules, produced from a 1800W PV array (around 22 sqm surface) catching 5 hours long 22KW sunlight = 110KWH sunlight needed to get 3KWH output from my fuelcell (ratio 2.7%) !!
The future of mankind: bringing this lousy ratio up to 20%.