Space-Based Solar Power Coming to California in 2016

Solar Satellite
The microwave beam is targeted at a rectifying antenna array on Earth. Designers say the beam would have about one-sixth the intensity of noon sunlight. Image credit: Mafic Studios Inc.
(PhysOrg.com) -- In the near future, a solar power satellite may be supplying electricity to 250,000 homes around Fresno County, California. Unlike ground-based solar arrays, satellites would be unaffected by cloudy weather or night, and could generate power 24 hours a day. If successful and affordable, the project could mark the beginning of space-based solar power in other locations, as well.

Solaren Corp., a solar power start-up, has convinced Pacific Gas & Electric (PG&E), California's largest utility company, to purchase 200 megawatts of electricity when its system is in place, which is expected to be 2016. According to Solaren, the system could generate 1.2 to 4.8 gigawatts of power at a price comparable to that of other renewable energy sources.

In Solaren's proposal, satellites would be positioned in stationary orbit about 22,000 miles above the equator. The satellites - whose arrays of mirrors could be several miles across - would collect the sun's rays on photoelectric cells and convert them into radio waves. The radio waves would then be beamed to a receiving station on the ground, where they would be converted into electricity and delivered to PG&E's power grid. Because the radio beam is spread out over a wide area, it would not be dangerous to people, airplanes, or wildlife.

The plan requires a large area of land to host the ground receiving station's antenna array, and several square miles of scrubland in western Fresno County could provide an ideal location. In addition to being sparsely populated, the region is also near transmission lines and a load center. While many of today's land-based solar stations are located far out in the desert, a station closer to customers could offer greater convenience and economic advantages.

Gary Spirnak, CEO of Solaren Corp. and a former aerospace engineer, noted that the project will cost more than $2 billion, mostly going toward engineering development and building of the ground station, as well as launching four or five satellites. So far, Solaren has raised an undisclosed sum from private investors.

"While a system of this scale and exact configuration has not been built, the underlying technology is very mature and is based on communications satellite technology," Spirnak said.

Solaren's project is not the only space-based solar system in the works; Japan's space agency, JAXA, has recently begun testing a space-based solar array that beams energy to Earth in the form of microwaves. If the tests are successful, the agency plans to launch an array of satellites that would transmit power to a 1.8-mile-wide receiving station, which would generate enough to power about half a million homes.

More information: Q&A with Gary Spirnak

via: MSNBC and Fresno Bee

© 2009 PhysOrg.com


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Apr 15, 2009
Uh... What? You're backwards in more ways than one.

Apr 15, 2009
Zev you certainly have the right to your opinion, but it would help the rest of us if you explained not only the alternate proposal you stated but also why this is a bad idea.

Seems to me an energy generation technology not based on nuclear or fossil fuel, and not subject to the usual weaknesses of "alternative fuels" (dependent on wind, lack of clouds, facing the sun, etc) would satisfy both those concerned with global warming and also those just generally concerned with the long term viability of nuclear energy (radioactive waste and byproduct, security) and fossil fuels (scarce resource, security, environmentla impact).

Its a win-win from those aspects, in what way is it a losing proposition to you?

Apr 15, 2009
Fitting solar panels to homes would be a more efficient way to generate energy.

Plus solar farms with around 6 to 9 solar panels per pole, could feed into the national grid.

Is this satellite just a cover for a more sinister militarised approach, a death ray in space.


Apr 15, 2009
Grab your tinfoil hats.

But no, really, 2 billion would build a fucklot of solar panels for housing and solar farms.

Plus "a price comparable" doesn't really say much. The price of a Bentley is also comparable to the price of a bicycle. It's a lot bigger.

Apr 15, 2009
Fitting solar panels to homes would be a more efficient way to generate energy.

I disagree. Basing the system in space gives a direct view of the sun, regarding of planetside weather, time of day, etc. What you lose in efficiencies switching back and forth between wavelengths you make up for in steady supply, which has been the weak spot in solar energy up till now.

Plus solar farms with around 6 to 9 solar panels per pole, could feed into the national grid.

Sloar farms get the attention (and the following wrath) of the NIMBY environmentalists. aka "we want alternative energy, as long as it doesn't have ANY visual or environmental impact. At all."

Is this satellite just a cover for a more sinister militarised approach, a death ray in space.

You were doing so well until you went all paranoid on us.





Apr 15, 2009
Fitting solar panels to homes would be a more efficient way to generate energy.


Agreed. Concentrating solar panels are the way to go.

Plus solar farms with around 6 to 9 solar panels per pole, could feed into the national grid.


Exactly. Terrestrial solar can utilize existing electrical infrastructure.

Is this satellite just a cover for a more sinister militarised approach, a death ray in space.


It is a perfect death ray. The microwaves could be tuned to affect specific materials. The only catch is that the beam is wide so it would be good to clear an entire sector of life/electronics on the ground.

I would also add that converting gigawatts of solar energy to microwave energy would generate a massive amount of heat. The satellite is located in a vacuum which is a wonderful insulator. So you have huge overheating problems. Add to that the exhorbitant cost of putting the satellites into a geostationary (Clark) orbit (> $10,000 per Kg)and keeping them there. Large solar panels act like solar sails.

IMHO the only way to go is to set up massive terrestrial solar concentrator farms. Reflectors are cheaper to produce that the photovoltaics. There are vast tracts of inhospitible desert in the USA bathed in intense sunlight.

Apr 15, 2009
1/6 th the intensity of noon sunlight...

Duh, why not use sunlight which is 6 times more intense?!*#

Anyone want to invest in my machine that transmutes poo into gold? No prototype yet. I just need a few billion to construct a massive neutron bombardment facility. And for those who worry about all of the radioactivity - don't worry you can't see radioactivity so it is harmless. We will locate the facility in some city center to make it easy to carry the gold to the banks.
;-P

Apr 15, 2009
If the receiving field is 1.8 miles square, that is roughly 90.3 million square feet. Moderately efficient solar cells produce roughly 14 watts/square foot, yielding roughly 130MW. Extremely efficient solar concentrating systems might be able to get that yield up to 20 watts/sqft, for 180MW yield. If the numbers they throw out at the top of the article, 1.2 to 4.8 GW, are for this receiving field that is an order of magnitude greater yield for the land used than the yield for land based Photovoltaics. If their numbers are more than salesmans promises, we probably should look into this.

Apr 15, 2009
Check the date. Methinks april fool's hoax.

Apr 15, 2009
This is what I get when I click on the top google link for Solaren Corp, www.solarenspace.com/:

"webadmin.registerapi.com uses an invalid security certificate. The certificate expired on 8/27/2008 7:27 PM."

Doesn't really inspire a lot of trust. The third link leads to a completely unrelated Armenian company with a very similar name.

Apr 15, 2009
2 billion?? Try hundreds and hundreds of billions. It costs sooooo much for NASA just to put their panels up in space for the ISS. Miles of solar panels will cost sooo much more. And what about drag from particles high up there where the ISS is. These solar panels will act as sails and bring them back burning up in our atmosphere. Unless they are constantly refueled with matter for ion jets. What about other satellites / planes crossing this microwave beam. It makes so much more sense to put any money into ground based systems. The efficiency of solar panels is increasing every year.

In 2016 this great idea will be like what turning corn to fuel is now, stupid and very expensive.

Apr 15, 2009
I am sure there are many technical problems to overcome, and I will believe it when I see it, but if they do build a prototype, and it delivers anything close to what they say, it will be a great feat, and let's face it, we need some more greatness, instead of all this self-hating of mankind.

If a government was talking about building this, I might be concerned about ulterior motives, but not private enterprise. We're not talking about some James Bond villain here. This is a company of forward thinking individuals trying to profit by providing a service. If it doesn't work, or it doesn't get built, it is their loss (with the possible exception of some hefty tax write-offs.) If it does work, then they will have advanced the technology by a great leap and we all reap the benefits.

In addition to the stated purpose, this thing could also be "rented" to feed power to other satelittes, a fledgling space station or moonbase, until they can get their own facilities built. Yeah, you'd need a tighter beam and a very precise antenna, like the one they used to beam power across a room and power a 60 watt bulb, but it might make some projects possible that would otherwise languish in the planning stages.

Apr 15, 2009
Check the date. Methinks april fool's hoax.
Check page no. 12,847 of the stimulus bill Congress passed... You'll probably find this project has already been funded under a Pelosi earmark loosely titled "Transporter Beam Research".

Apr 15, 2009
Their technology is undefined. The distance is too
great, by the time it gets to Earth it will be 100
miles across. They haven't figured out many of the
technical issues.

Annoucing garbage to be announcing garbage doesn't
place you in any higher order. It just makes you
look like a clown.

Apr 16, 2009
So I know that my science skills are maybe lower than others that would normaly read articles on this website, but I have a question. I remember reading stories about Tesla that said he had designed a way to beam electricity in a radio type frequency and he had put a receiver into a car and drove the car a fair distance if i remember the story correctly. The point being, if they can beam this electricity back to earth from a satelite, and it is already several miles wide, cant they put a small receiver in our homes and cars to run electric motors. We could have batteries in the cars in case we were in a tunnel or whatever, but they beam satelite all over the county now. SIRIUS is proof of that, and we never lose the signal anywhere in the county. Whay cant they do that with an electrical beam broadcast to our SIRIUS radio that would convert the signal to electricity for our batterys to run on. Just a thought................

Apr 16, 2009
*zuggerjack* I was thinking along the same lines...this has the potential to actually INCREASE atmospheric temperatures (since the water in the air would heat up quickly)...then we would definitely be talking about global warming!

Apr 16, 2009
*zuggerjack* I was thinking along the same lines...this has the potential to actually INCREASE atmospheric temperatures (since the water in the air would heat up quickly)...then we would definitely be talking about global warming!


Don't forget the powerful greenhouse gases released into the atmosphere by the manufacture and cleaning of solar cells used in such projects. We are talking about gases capable of up to 17,000 times the radiative forcing of CO2!



Talk about destroying the planet to save it! :)

Apr 16, 2009
So.... Math check:
1.8 square miles = 4.66 million square meters
4.8 GW/ 4.66million sqare meters = 1030 Watt/m^2

Hm... less than we would get from sunlight, but lets assume it's always on, round the clock. (satellites can still see the sun when its night time here)
So you actually get over twice the energyper square foot because it's always on. Oh and it makes for BASELOAD too :)

Part 2:

Cost per Watt: Solar panels on earth are readily available for $800/100W (180W really, but lets talk likely output power)

So for $2 billion you get 2.5 million pannels or 250MW of power generated when and where they are needed the most - hot summer days when the AC's are cranking, but only during the day... (also not counting infrastructure to mount all these pannels. )

The math sense checks out, but are their numbers accurate?

$2 billion sound awfully tiny for a solar array "several miles across" let alone 5-6 sattelite launches (aren't they about a billion each?) Maybe $2 billion for the ground station and someone else takes care of the sattelite?

Oh and one small storm of micro-meteors and your satellite array is swiss cheese? One happens about once/year

Apr 16, 2009
Zev you certainly have the right to your opinion, but it would help the rest of us if you explained not only the alternate proposal you stated but also why this is a bad idea.


It costs $11 000 per kg to place something in geostationary orbit.

The most promissing power transmission technology put forth by proponents is a 2.45 GHz microwave antenna about a km across in space and the reciever on Earth about 10 km across. It doesn't matter if you're sending 1 W or 1 TW, the antenna has to be that big if you want to reduce losses to 20% or less.

The energy density hitting the Earth based antenna will only be ~100 W/m^2 for an insane 100 GW of solar cells in space. That's over 10 times the solar cells produced anywhere in the world to date.

There are too many steps and you lose power at each one. First you convert from low voltage DC to low voltage AC, then from low voltage AC to high voltage AC, transmit it several kilometers across the array to the antenna; convert from high voltage AC to low voltage AC, convert from low voltage AC to low voltage DC, convert from low voltage DC to microwaves in a microwave antenna, beam it 36 000 km from geosynchronous orbit to an antenna on Earth, convert back to low voltage DC, convert to low voltage AC, convert to high voltage AC and send it into the grid.

The photovoltaics will be bathing in ionizing radiation and will age faster than on Earth.

Apr 16, 2009
OK, I'm a little confused about the whole stationary orbit thing. Apparently, they're referring to a geosynchronous orbit, i.e. the satellite stays in the same spot in the sky. Wouldn't that lead to Earth periodically eclipsing the satellite? That would nullify the whole continuous power supply advantage, wouldn't it?
Then again, assuming they're talking about keeping the satellite in the same spot relative to the sun and Earth(I'm not entirely sure how that would work other than continually adjusting the orbit or Lagrange points), that would mean a great deal of precision would be required. Also, there are a lot of possible disturbance factors, from weather to air/space traffic, which would limit the already small window of time in which the power could be transferred. The receiving station would most likely have to be linear in shape, what with the beam moving constantly.
Well, I'm not convinced. Perhaps it'd be a good means of powering other space constructs, and it's hard to ignore the military possibilities, as previous posters said, but the means of transporting the energy back down is too risky for the time being. I don't understand why so many resources are spent idiotically on satellites and space exploration probes when we're still launching them with the same centuries old technology. The new space race should be an endurance one, or no race at all.

Apr 16, 2009
OK, I'm a little confused about the whole stationary orbit thing. Apparently, they're referring to a geosynchronous orbit, i.e. the satellite stays in the same spot in the sky. Wouldn't that lead to Earth periodically eclipsing the satellite? That would nullify the whole continuous power supply advantage, wouldn't it?


The Earth's rotational axis is tilted and you're orbiting so far away from the Earth that you're only going to be in the Earth's shadow for up to 70 minutes per day.

More importantly you know exactly when and exactly how long this will occur; there are no seasons or weather that can screw things up.

Apr 16, 2009
That cutesy picture of a small antenna in the middle of a farm is extremely silly.

Reality is closer to the Chernobyl exclusion zone. It would be a zone ~30 km across with an antenna ~10 km across in the center. The zone would be uninhabited because the microwave power exceeds legal tolerances(whether a few watts per metre is harmful or not is a completely different question).

Apr 16, 2009
In regards to Soylent's response:
Hmm...And I suppose that's the optimal period for the transfer to occur, since the satellite would otherwise be idling.

The solar panels themselves wouldn't be affected, true, but what about the ground station and the microwave beam? This might be a stupid question, but how does refraction fit into all of this? The beam would traverse air of different densities(and other properties, maybe) on its way down, and these properties are in fact weather-dependent, right?

Apr 16, 2009
First they want to block the sun by shooting particles in the atmosphere and now this?? This is madness!
With developments in electrical storage we don't need sunlight 24/7. This is just an excuse for political and military agendas.

Apr 16, 2009
Okay, maybe I'm missing something, but wouldn't transmitting microwaves in a spectrum that causes dielectric heating in water cause huge losses as the beam travels through the atmosphere?

http://en.wikiped...ted).gif

The microwave spectrum is very wide and isn't just the 2.45 GHz that a microwave oven uses. Wouldn't they choose a wavelength that had high transmittance through the atmosphere (and hence low dielectric heating losses)?

Apr 16, 2009
In regards to Soylent's response:

Hmm...And I suppose that's the optimal period for the transfer to occur, since the satellite would otherwise be idling.


You couldn't even build such a massive storage system on Earth, you're not going to do it in space.

Power must be continuously transmitted the very millisecond it's produced.

NOM
Apr 16, 2009
Anyone want to invest in my machine that transmutes poo into gold?

Carefull googleplex, The great inventor Neil Farbstein has already invented this. He may sue you for stealing his idea.

Apr 17, 2009
This would be like a giant microwave. That can cook a giant tv dinner. That can feed a lot of people.

Do it.

Apr 17, 2009
So long as this is a geosynchronous sat then this question is mearly for my own curiousity as I have little to no interest in the state of california. Is the power output of the microwave antenna array 1/6 of the microwave intensity or are the microwaves 1/6 of the sun's intensity. that would seam to make a minor difference in the "safety" of the people in the receiving area.

Apr 17, 2009
Is the power output of the microwave antenna array 1/6 of the microwave intensity or are the microwaves 1/6 of the sun's intensity. that would seam to make a minor difference in the "safety" of the people in the receiving area.


1/6th of the sun's intensity(which makes the recieving antenna very costly).

The radiation pattern is an airy disk, and fairly significant "lobes" extends several times the diameter of the recieving antenna.

Microwaves are in the evil part of the electromagnetic spectrum know to its frantic opponent as radiation(the only non-evil part of the EM spectrum is visible light; it is of course also EM radiation but no one calls it that). As such it will be visciously opposed by the chronically ignorant and a safety distance several times the diameter of the reciever will be imposed whether or not it makes any sense.

Apr 18, 2009
I'm still leaning towards the space elevator that can extract electricity from the magnetosphere and simply run it down the cable to the ground for our use.

Apr 18, 2009
The space debris and micro meteors will trash this thing. Who will be settling the lawsuits for the shadow this thing puts on landowners residential and commercial property?

Apr 18, 2009
All well and good, however if one bird dies California will scrap the whole thing... Also, what keeps the solar wind from pushing this thing around? Besides isn't California already hemmoraging cash at the rate of about a billion a week? I could be wrong but I think it may be time for a reordering of priorities.

Apr 18, 2009
Who will be settling the lawsuits for the shadow this thing puts on landowners residential and commercial property?


Shadow? This thing is several Earth radii away!

Apr 18, 2009
Why just beam the power directly to the homes from the Satelite? ... like the way we get satelite TV signals...

Tesla did this almost 100 years ago from a transmitter on the ground delivering power 20 miles away. The only thing wrong with his idea at the time was that Edison could not figure out how to put a meter to charge people for the electricity delvered without wires.

Apr 19, 2009
I find it hard to believe this will not have any serious health effect to the people working at the conversion sites over time.



To get that much energy out of radio waves they need to be eXtremely intense.



I guess we'll find out in 15 years after we've been running them.



I'd rather spend the money on a terrestrial farm. We shouldn't be clogging up outer space more than we need to. Besides one well aimed coronal mass ejection and the whole thing is toast.

Apr 19, 2009
I find it hard to believe this will not have any serious health effect to the people working at the conversion sites over time.


No. Microwaves heat flesh and that's all they're capable of doing.

If half a century of research on the biological effects of high power microwave and radiowave transmitters in all possible frequency ranges didn't silence the tinfoil hat crowd who thinks cell phones give them brain cancer, nothing ever will.

Apr 19, 2009
Microwave exposure also leads to mental instability due to heating brain tissue near the surface of the skull. People who are exposed to such radiation become irritable and so forth. That is why it is recommended that people replace their microwave ovens if they develop symptoms or if the ovens leak radiation.

They do sell microwave radiation detectors for home use, by the way.

Apr 19, 2009
Microwave exposure also leads to mental instability due to heating brain tissue near the surface of the skull. People who are exposed to such radiation become irritable and so forth.


Decimal dust.

I have this amazing cooling device called a circulatory system and sweat glands that allow me to keep thermal homeostasis.

Even when I directly expose my head to 1000 W/m^2 of UV, visible and infrared radiation for hours on end it has negligible effect.

I'm even capable of submersing myself in 45 degrees celsius hot water for long periods of time without experiencing anything worse than a bit of fatigue.

That is why it is recommended that people replace their microwave ovens if they develop symptoms or if the ovens leak radiation.


No, that is why quacks recommend replacing microwave ovens when they leak a few hundred milliwatts of evil, evil microwaves. Did I mention that microwaves are invisible and they're evil?

They do sell microwave radiation detectors for home use, by the way.


"They" are quacks who prey on the ignorance of their audience to sell overpriced crap they do not need and do not understand how to interpret.




Apr 19, 2009
Soylent, I just have to say your posts are an inspiration to many. We can only aspire to such witty insight.

Seriously though, I do enjoy your posts. It's nice to know other people are proponents of the scientific method.

Apr 20, 2009
Ok, soylent, here is an experiment for you to try. Please rig your microwave oven to run with the door open just a crack. Then, stand about five feet from it after turning it on. Do this every day for three months. Please have someone who knows you record the results and data as well as video evidence and notarized documentation. Let's see how well your remarkably cool brain works afterward, shall we?

Apr 20, 2009
Ok, soylent, here is an experiment for you to try. Please rig your microwave oven to run with the door open just a crack.


I have run the microwave on full with the door open back when el cheap-o microwaves didn't have a switch to turn it off integrated into the door mechanism. That's about 1000 times more leakage than the leakiest microwave you can find.

Do this every day for three months.


What the hell for? It's not cummulative.

Apr 20, 2009
They do sell microwave radiation detectors for home use, by the way.

They still sell those? We had one of those when we got our first microwave oven. We used it (the detector) obsessively at first, then periodically when we thought of it, then eventually when we changed the batteries on the smoke detectors we would check the mocrowave for leaks... when we upgraded to a newer microwave we tag saled the detector. The newer models have safety features and we now better understand what appliance generated microwaves can and can't do to you if you are exposed to them.




Apr 21, 2009
They have to pass EPA tests on the effects of radio waves on people. They are operating on unproven assumptions, that there will be no effect on the weather or the ozone layer or radiation shielding from the magnetosphere

Apr 21, 2009
Microwave exposure also leads to mental instability due to heating brain tissue near the surface of the skull. People who are exposed to such radiation become irritable and so forth. That is why it is recommended that people replace their microwave ovens if they develop symptoms or if the ovens leak radiation.



They do sell microwave radiation detectors for home use, by the way.


The most common effects of microwave oven leaking radiation is damage to the corneas and cataracts that can develop from as short as two minutes exposure. That has been proved in countless cases.
There is a big possibility that long term exposure to microwaves near a satellite electricity plant might cause cancer, cataracts, neuro symptoms, etc. The EPA should hold up their project.

May 06, 2009
...
What the hell for? It's not cummulative.


Ok, I see you are afraid to try the experiment....

May 19, 2009
Ok, one more time, yes Microwave heat water, no they don't directly rupture cells or cause immeadiate mutations leading to superpowers or giant lizards, okay, that's out of the way, a Home Microwave is between 600 to 1200 Watts, average. this thing puts down on eavery car about the same level of radiation. couple in the complication of metal in the microwave, add the issue of only 1/6 of solar radiation is valid except we are going from a diffuse broad spectrum to a guided spectrum. Lastly if microwaves are safe then why is the military wasting money on LTL microwave crowd control dishes when they coould just as easily use a microwave communication dish? could it be that microwave communication dishs are not LTL?

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