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Science

Planned Constuction of Orbiting Microwave Power Station 244

Posted by Hemos from the fun-with-solar-energy dept.
Fith writes "A small news item tells of a research project to build robots that will assemble and repair a gigantic orbiting solar collector. You'll have to scroll down a bit to find the section. Basically, power collected will be beamed back to earth using 'safe levels' of microwave energy. " This is a proposal that's been floating around for quite some time-vast LEO or HEO solar panel arrays, beaming the power down to earth. For those of you who played, Simcity2000, this was one of the power options as well. NASA hopes to part of this operational by 2015.
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Planned Constuction of Orbiting Microwave Power Station More

Planned Constuction of Orbiting Microwave Power Station

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  • Welcome to the Wonderful World of Science FUD.
    Your fears of "what if it makes a **super** bacteria" are, and I am not exagerating, exactly as likely as saying "exposure to twinkies will cause a **super** bacteria to mutate".

    Here's Why:
    1) Anything which causes chemical damage to DNA is technicaly a "mutagen".
    2) Almost everything is a "mutagen". (well, thats an exageration, but lots and lots and lots of stuff is a mutagen).
    3) Because of this, everything (especialy things with **short** life cycles like bacteria) is constantly mutating.
    4) The vast majority (read 999,999 out of 1,000,000) of mutations are **HARMFUL** to the life form. (Imagine, what is the likelyhood that smacking my computer with a hammer will make it work **better**?)
    5) Air Bourne Bacteria is almost always in spore form (low water contenet, almost no chemical activity), and damage to bacterial spores makes it rather hard for them to reinstate, but thats okay for the bacteria, because they produce so MANY spores.
    6) Evolution is pushed by small changes, (ie. many little benificial mutations **in**a**row**) so to get a **super**bacteria** from a radiation stream, you would basicaly be asking the hammer that you just hit your desktop computer with to produce a Cray out of the ruble.

    Remember boys and girls, evolution needs TWO things, a mutation source, and a selector (this one survives better than that one AND has more kids), and randomly blasting out radiation WILL increase the rate of mutation, but it wont DIRECT it. This is why we dont have flying cats, despit all the fun chemical mutagens that we expose ourselves and our pets to every single day. (like caffine) and all the fun energy ones weve been exposed to for ages (UV radiation, physical stress (like being slapped), strong temperature gradients, etc.)

    But for anyone who doesn't believe me, go get your Junior Quack Scientist Memebership Card(tm) and go off and study ball lightning and bigfoot.

    -Crutcher
  • After all, first we generated power by burning wood, oil, coal and gas. So they came along and said this was polluting the environment, causing acid rain and global warming. We start building nuclear power plants but they don't like that either -- though I never quite figured out the arguments against it.

    This is certainly going to flip their lids; all they need to see are words like "microwave" and "radiation" and they'll be off their trolleys.

    Makes you wonder where they think the juice should come from. Or would they be happy to go back to living in mud huts?
  • How do you keep birds from flying into the beam area


    This is an interesting question to me. Also think of planes(they would be easier to control though). Hopefully NASA is well on their way to solving the dispersion problem, but the problem of things overhead seems like it would be very difficult to solve.

  • Hmm, I admit that I'm no expert here. Fusion probably isn't quite as perfect as I made it out to be, and still might exhibit some radiation leakage.

    I suspect that the reason that there is no commercial plant in the works is that it is *extremely* expensive (in dollars) to get an energy profit from a fusion reaction. Fusion reactions aren't very sustainable, or very efficient, at the current state of the art. They do turn a slight energy profit in pulses, though.

    However, fusion research seems a lot more promising than space-based microwave power. Fusion is also (in principle) *far* cleaner and more efficient than fission. However, it is still a heinously underfunded avenue of research (so it seems to me), relative to its potential eventual payoff.

    Of course, I am indeed hand-waving without any actual numbers in front of me; however I *believe* that the last set of grants in this area only amounted to tens of millions of dollars. Even if the real number is an order of magnitude higher than that, it still seems to be an order of magnitude too low. A billion or two here would be well worth it, especially considering all the other places we're spending money these days. What I'm talking about here, in terms of a research goal, is the difference between waiting 20 years and waiting 50 years for the first commercial fusion power plant. At any rate, IMHO fusion is still a better investment than microwave power.
  • 1. One set of comments were concerned with a metal-skinned airplane flying through the microwaves. This writer obviously didn't remember his high school science classes, otherwise he would have known that a metal-skinned airplane is a Faraday Cage, which prevents radio waves from penetrating the interior

    Airplanes have windows.

    Bye bye.

  • Seriously, why not use the structure as an antenna?

    Plus, it'll be out of the atmosphere, miles away from human RF interference and with the atmosphere between most of the noise and the antenna, and in a high orbit above the other satellites.

    I'm not an aerospace engineer, but this seems like it should be possible.

    Jon Acheson
  • This might work as well as harvesting the Kinetic Energy of Asteroids hurtling down Earth's Gravitional Well. :-)

    -- A wealthy eccentric who marches to the beat of a different drum. But you may call me "Noodle Noggin."

  • The funny thing is that different plants actually extract and concentrate different isotopes of atoms.


    This is definitely true with corn, which at harvest contains a significantly higher concentration of Carbon 13 than the surrounding environment (plants, soil and air). Carbon 13 is non-radioactive and harmless, but makes up only about 1% of naturally occurring carbon (the rest is ~98.9% Carbon 12, and then there's a smattering of C14 which is used in carbon dating). The corn plants actually favor using the C13 in their chemical processes and end up with much greater than the natural 1% concentration.
    People who eat a lot of corn, therefore have a higher C13 concentration in their bodies, and are isotopically heavier than those with a low-corn diet. Might lead to an interesting weight loss program!


    Either way, other plants also favor different isotopes of elements, so it wouldn't be surprising to see plants that contained higher concentrations of Potassium 40 (natural radioactive potassium), radioactive phosphorus, and other naturally occurring radioactive elements.


    Ever pointed a geiger counter at an open container of salt substitute (KCl - potassium chloride, instead of normal salt NaCl - sodium chloride)? It goes nuts! Lots of happy "natural" radiation right there.


    -Tec -who used to work in a medical lab with C14, H3, and other paranoia inducing materials...

    ------------------

  • It might be feasible to outfit the windows with a nearly transparent, fine wire mesh to prevent them from acting as cavity radiators to the passengers and crew.
  • Thousands of years? Nahh. Just keep it till its cheaper to lob the stuff into the nearest star than it is to store it properly. I'd give it a couple centuries, tops.

  • More NASA vapourware. BFD.

    NASA's job is to spend funding on studies that they can hype to Congress to get them more funding. Every once in a while they follow through on a project if the right congresscritters get some pork out of it, but of course the engineering (and science, if any) suffers for it.
  • Solar cells pull 75W/m^2 and harness the proven energy of the sun. Side effects include sunburn.
  • The Canadian built CANDU reactor is another story however. As a heavy water reactor, neutrons are slowed to a point where the U-238 (the most abundant Uranium, especially since CANDU's use straight ore for fuel) is converted to Pt-239 through a short and fun nuclear reaction.

    Thanks to this reaction, CANDU reactors have a very high Plutonium output. Which I imagine the Canadian government exploited by selling the spent fuel rods (with all that nice Pt) to the states.

    This also explains how countries like India now have an ample supply of nuclear weapons. We sold 'em CANDU reactors.

    The lesson to be learned? Canucks are smart. We got electricity AND got to sell that pesky nuclear waste to the bombmakers. (I can't tell if I'm being sarcastic, sorry)
  • Wave power generators may not dump hot water, but they wind up making the water cooler, since they are extracting energy from the water. That energy will wind up somewhere else as heat.

    This leads to an interesting problem with the microwave issue: it changes the thermal balance. We'd be intercepting sunlight that would have otherwise missed the earth and sending it down to the earth where it will, ultimately, be turned into heat to be reradiated back into space. The result is to increase global warming.


    ...phil
  • I thought Las Vegas was like that already.


    ...phil
  • > As to your "super bacteria" resistant strains of bacteria crop up all the time, but its not due to radiation in any way. The more we use antibiotics, the more bacteria is exposed to them, which then evolve to be resistant.

    There was a really good article in Discover Magazine about a year ago about this. It was really interesting. I no longer use antibiotic products around the house.
  • This proposal would convert light into electricity into microwaves back into electricity, with power loss occuring at each step.

    Wouldn't it be more efficient to just put mirrors in orbit focused on a ground based solar array, or even a biomass farm? The mirrors would be cheaper, lighter, and less maintainence, and as new photovoltaic technology comes along the ground based equipment would be easier to upgrade.

    Of course, you would have to limit the intensity 2 or 3 x of normal daylight levels. Ask any ant what a focused light beam can do.
  • Wrong kind of radiation, dude. :)
    ---
    "'Is not a quine' is not a quine" is a quine.

  • Re:Radiation & Brains (Score:1)

    by Anonymous Coward
    the only part of your cheerful little story that I don't buy into is the "rocks are radioactive" part of it. Some rocks are more than others. Some air is more radioactive than other air. Was the lichen radioactive due to naturally occuring exposure, such that it would have been the same level a century ago?

    The world is full of many different phenomenon.

    It's also filled with anecdotes trumpeted by people with an agenda.
  • Or significant power stations that have to be shut down because of leaks and fires in Japan, Canada and the USA? Hmmm?

    If what I said is nonsense,
    I'm making a point with it.
    If what I said makes perfect sense,
    you obviously missed the point.

  • safe levels? (Score:3)

    by jetson123 ( 13128 ) on Thursday July 15, 1999 @10:04AM (#1800460)
    Even if it's designed to use "safe levels" during normal operations, whoever may put it up will be subject to suspicions that the satellite can be reconfigured for military purposes. In fact, any large power source in space, whether nuclear or solar, will suffer from that perception.

    Also, while a single power plant may not have a big impact, with global warming being a concern, collecting more solar energy and focussing it on earth is the wrong direction to go in.

    The solution to energy problems on earth seems to me not to beam in more energy from space but to conserve more energy at home. The US in particular is so wasteful of energy that the kind of money spent on those projects would be better spent on some simple, down-to-earth conservation programs.

    (I also wonder why this particular avenue is being pursued. Technically, it would seem that simple mylar reflectors in space for night time lighting of urban areas would be a much more logical first step. They could help conserve a lot of energy, would be technically much simpler, and couldn't be easily repurposed for military use. To me, that alternative makes the microwave-based approach suspiciously look like dual-use technology and a boondoggle for certain kinds of research.)

  • ...and it's anti-radiation damage effects, otherwise I might be really worried. Can everyone sing that BNL song about the "hydrofield in my backyard?"

    If what I said is nonsense,
    I'm making a point with it.
    If what I said makes perfect sense,
    you obviously missed the point.
  • I would like to find more about it but you have given the wrong address. I have been wondering for ages why this idea hadn't been pursued. I just assumed the microwaves would cook everything in it's way...
  • Of course, none of this invalidates his point. So he's a little off on his history of the Price-Anderson act, does that mean that his objections to it are any less valid?

    Note: I'm not familiar with the act, so I am not stating an opinion on it per-se. I'm only staing my opinion of this reply that is -- intentionally or not -- trying to change the subject without answering the actual challenge.

  • This is a great idea (Score:3)

    by Rayban ( 13436 ) on Thursday July 15, 1999 @09:14AM (#1800469) Homepage
    Microwave energy would be cheap and clean to harvest from space. I'm sure we all remember the Simcity 2000 disaster where the microwave beam went "off-target" and traced a path of destruction across the city, however. :)

    In real life, I don't believe we have to worry about such things.

  • with that much power, the birds wouldn't just start to cook, they'd explode...
  • Remember the microwave disaster in simcity? Can't wait till my roof get pierced by a beam of radiation -- maybe it will hit whatever I was about to put in the microwave oven and cook it for me!
  • Evidently Amazon is moving into this business. I was thinking about getting a few yottatons of topsoil, but the UPS service around here is lousy. Also I'd need a bigger shovel.
  • But what if the beam misses the power station here on earth? What if it blows up all the surrounding arcologies??
  • Y'all

    Experiment:

    Only tangential to all this fun and games but please [do|don't] try this at home.

    Open your trusty microwave oven and stick some duct tape over the air vents.

    Now take a candle, a really smokey one is best, light it and put it in the microwave.

    Shut door and nuke at full power.

    Expected result:

    Lots of buzzing noise and flickers of electrical activity show up in the candle flame, often starting in the wick. If you are lucky 'globs' of purple plasma will break loose from top of flame and exist as free floating fireballs in the microwave cavity for several seconds.

    Microwave oven may burst into flames, so may duct tape, this will probably invalidate your waranty.

    Candle will remarkably not melt during reasonable duration tests.

    Conclusions:

    Parafin wax has little interaction with microwaves and does not appear to heat up much.

    Carbon in burning wick and smoke from candle provides a conductive antena absorbing microwave energy, rapidly heating the carbon. In some conditions this can produce a conductive plasma that will continue to absorb microwave energy and make small burn marks on the inside of the case if it touches down.

    Duct tape can spontaneously combust when subjected to harsh microwave environments.

    Disclamer:

    Are you stupid ? This can fuck up your microwave, trip your circuit breakers or burn down your house, you do this at your own risk, bne ready to switch off the wall socket if it gets too scary ! fire extinguisher close by may also be a good idea. You do this at your own risk.

    Further experiment:

    If you can work out a way to pump microwaves into a magnetic containment field you may be able to produce a beautiful yet deadly microwave driven plasma sculpture floating in free air. Only view through several inches of lead glass, tight wire mesh or big fishtank.

    C Ya !
    Robin.

  • Re:Oh poo (Score:1)

    by Anonymous Coward
    Actually, well-run nuclear plants are the are one of CHEAPEST form of electricity generators available. Hyrdro/Wind is cheap too... Depending on the type of reactor, nuclear costs $0.02/kW to $0.03/kW while gas/oil/coal costs $0.03 - $0.04 per kW....Where nuke plants got screwed is back in the 70's the government planned for a nationwide disposal place in Nevada, but the states in fear bitched, (NIMBY syndrome over the transport), and thus now plants are stuck holding the waste locally in pools in concrete blocks....
    I consult for a local power company that runs several nuke plants, and if there are any how costs associated with nukes it's due to the NRC & other regulatory committees, but that's the price we pay to have safe Nuke plants (when was the "real" accident in the US? TMI - About 20 years ago?? (And that really got blown out of proportion)
  • You've said it better than I could have, but I did have one minor quibble about the "greenhouse effect."

    The "greenhouse effect" occurs on any planet with an atmosphere, be it oxygen, nitrogen, flourine, whatever. Light passes through the atmosphere, warms the planet's surface, and the atmosphere prevents the heat from escaping because it is more opaque to infrared than it was to visible light. This is a Good Thing: without it the earth could not support life; you'd get deadly temperature variations like on the surface of the moon.

    What you're referring to is runaway greenhouse effect, as seen on the planet Venus. Basically, the composition of the atmosphere determines how much heat it holds in. Venus' carbon dioxide atmosphere (and its closer proximity to the sun) cause it to hold in lots more heat, and thus the surface of Venus is a furnace.

    Like so many other things, the greenhouse effect is not bad in and of itself, unless it gets out of control.

    Please forgive my intrusion, but like misusing of "hacker," this just hits one of my buttons.

    Jon
  • I would think that the ignorance level about this field of science would be pretty low here on /., but 'nuclear' carries a deep stigma. Too bad, since it holds tremendous promise for plentiful energy. The U.S. will have to face a fossil crisis in the forseeable future, and by then, we will have to buy power from Canada, or beam it from space. Uranium is cheaper.

    I'm not a nuclear expert here so I'm very well likely to get schooled pretty hard (and I encourage it please) but what about the 'hot' waste from nuclear power plants? If I'm not mistaken the boron rods can be used in cancer treatment in hospitals but what about the spent fuel? Doesn't it have to be put somewhere for a very long time?

    I'd prefer fusion over fission but I think we're a ways from there yet.

    Andrew
  • cool...if they merged it with that electro-shock gun they could open an ionized stream to something and vaporize it by channelling the power of the sun to it...neat-o
  • These answers are not actual answers. I'd have to check my 'propaganda machine' in order to provide sources, references and hard numbers, but...

    1) How much fissionable fuel do we really have given _current_ technology?

    Essencially limitless. I say this because I've seen projections of consumption and demand (granted, from pro-nukes). These guys feel that nuclear power could supply all of the worlds power needs for thousands of years. Sans fossil, at linearly increasing demand.

    Also, I've heard that the fission power would provide enough juice to get fusion off the ground. There's enough hydrogen in them there oceans...

    2) Do you have a good waste disposal solution?

    I'd said in other posts that the only reason there even is a high-level waste problem, is the regulations imposed on nuclear facilities. The same tech that reburns waste down to an inert state can be used for making weapons, and the Fed doesn't like that being publically available. After all, if the TVA decided to sell Plutonium to the Contras, all hell would break loose.

    As for disposing of low-level waste, well, that's equivalently radioactive to the coal ash that comes out of a traditional fossil plant, if not less so. We use that crud to pave highways and fertilize fields.

    3) given that wind power is cheaper per kWh (yes, true go research it!), how can you justify the cost?

    Actually, here I agree with you. Renewable, 99.44% pure enrgy sources are preferable. There's no risk of accident - no matter how small. Sure, the tower might collapse and kill someone, but it won't render the landscape useless for millenia.

    But the wind dies down, the clouds roll in, rivers dry up now and again, and Greenland is so far away. Fission is much more... predictable.

    I think that the key to successful power management is the same as for financial investments. Diversification.

    Use fossil as the first level, hit-and-run power source to get new infrastructure established. Then put in the nuke plant to serve as rock bottom supply and take the fossils offline. Then, based on the geography and weather conditions of a region, install an enviromentally passive system.

    I grant you, a 'natural' system would suffice if there were a single entity responsible for transmission and distribution of thus generated power over an immense area, but you have to accept that it would be a government monopoly. Can't make it work in a deregulated industry.

    The other option is to have smaller, cooperating entities, that can supply their rock bottom need (nuclear) and provide their own spinning reserve for nominal use. Then deal with the T&D issues with their peers.
  • Subject says it all. I can't get the page, that was fast.

    Rich
  • ...Spent nuclear fuel is no more radioactive than the rocks from which the fuel was initally mined in hundreds, not thousands, of years...

    What A Relief! My great, great, great, great, great, great, great, great, great, great grandchildren will be safe!

    Sorry for the sarcasm, but that has got to be one of the stupidist things I've read today. 'Don't worry, it'll be safe 500 years from now!' Of course we'll all be dead. But, hey! Nuclear power was worth it, right?
  • Ever felt like flash-frying a blue whale?

    I sure hope they can keep these powerstations on target when they beam the power down the the planet's surface! Of course, this would work way better than a nuke, so now we've got to worry about other countries building these things!

    SaDan
  • I'm glad to see you're so informed on this topic.

    *cough*kneejerk*cough*
  • OK, so they want to build a structure 22 miles long, carrying thousands of large solar collectors. It will be in geosynchronous orbit, so it should be in the shadow of the Earth for at least part of the day.

    So my question is, why not just build it in the middle of a desert here on Earth? It would probably cost an order of magnitude less than putting it in space.

    Oh, wait, this idea is sponsored by NASA, so of course it has to be in space.


  • All very good questions that aren't answered in the article.
    As for keeping birds from flying in the area, well you can't keep them out so I guess they consider all of the cooked birds as reasonable losses.
  • My sister is one of those "microwaves are bad" people. Never mind the amount of solar radiation that we get every day. I am sure that the fringe lunatics will go off.

  • And in related news... (Score:4)

    by jabber ( 13196 ) on Thursday July 15, 1999 @10:13AM (#1800496) Homepage
    Just think of the benefits that could be realized with microwave irradiation.

    We could maintain a comfortable minimum temperature in some of the world's coldest areas. Imagine, Fargo in the middle of winter, at a balmy 75 degF. Weather forecasters could actually guarantee tomorrow's highs. Swimming pools and car engines would always be warm, as would be the toilet seats across the nation.

    If we can tighten the beam enough, and develop super-precise satellite navigation systems, we could use one of these puppies for snow removal on the nation's highways. We could even melt a few hundred thousand acres of the Sahara for use as the world's biggest mirror for the world's biggest telescope..

    Now everyone, from L.A. to Bangor Maine can have a nice tan. Just go out during the designated irradiation period (day or night) and stare up into the sky. Oh, and all the stylish tinfoil hats we'd all have to wear. And clothes would stay 'fresh-from-the-dryer' warm, all day.

    Remember how grandma would cool off freshly baked pies by setting them on the window sill? Well, now we'll be able to thaw the Thanksgiving turkey that way..

    Just think, no more mosquitoes! At 6:30 each night, get off the patio. Then ZAP! 30 seconds later, not a 'skeeter in a 500 mile radius. Just be sure to bring in the pets.

    We could aim the thing at the Antarctic, and make the world's biggest ice sculpture... Seriously though, maybe carve off a big iceberg and haul it to where there's a drought? Well, maybe not.

    On the down side, leaving a dog in a closed car on a hot summer day would be kinder than leaving him out on the lawn. Hot dogs anyone?
  • Sounds like you may have some issues, here, stevie. Take a deep breath... good. Now, let's have some rational discussion... Keep breathing...

    The environmentalists that I respect realize there needs to be a balance and that we should look at maintaining the balance of various of Earth's systems for the long term good of all who benefit from those systems.

    Hope that helps you feel a bit better.

    Jason Dufair
    "Those who know don't have the words to tell
  • What they should do is either put the array in geo-synchronus orbit and then tether it to the ground and pipe the power down through the tether

    or put the microwave reciever on the end of the tether and beam the microwaves UP to the reciever.

  • Imagine what would happen if some tiny piece of space junk were to knock the orbiting collector off course? The bean would be moved away from its recieving source...probably vaporizing everything that it touches...

    It would be like a magnifying glass is to an ant...except it would probably be a much larger beam and we'd be burned to a crisp in seconds...


  • Sorry for the confusion. No, the receiving end does not need to do that much concentrating. The problem is at the transmission end, where the designs that I've seen concentrate power at a single point to beam it down to earth. Multiple concentrators with multiple transmitters is a possibility, but you start to add a lot of weight.
  • Oops, quite right. The trouble with "stream of consciousness" writing.

    Indeed, I read once that the average temperature on the Earth's surface would be below the freezing point of water, without the greenhouse effect of the atmosphere, thus putting it outside a naive definition of the "habitable range" in the solar system.

    Thanks for the reminder.
  • Well, yes...since the speaker from the SSI talked about it, *and* the *two* Environmental Impact Statements already done, WHEN HE SPOKE AT THE MONTHLY PHILA. S.F. SOC. MEETING AROUND 1982.

    And no, we are *NOT* talking about broadcast power, we're talking about it being beamed to receivers in places like the desert, from whence it would be fed into the power grid. Also, the power levels being discussed back then were around a few watts/meter sq., not enough to cook a vulture. Again, we're *NOT* talking about SDI-style Power Beams (tm) here.

    It would be the least polluting source of the electric power that we can produce...and before anyone starts arguing, consider:
    a) nuclear wastes;
    b) acid rain;
    c) river and estuary water warming from
    coolants;
    d) mining;
    e) transporting oil (Exon Valdez) and
    natural gas (pipelines).

    So...let's *go* for it, already. They've been babbling about it for half my life. I'd be *ecstatic* to go up there to help build it.

    mark
  • Uhhh, actually there are quite a few technically geeky, scientifically literate people who have concerns about stuff like this. Luddites are against technology in general, people for technology in general are just as bad. People who find some technology frightning are just intelligent.
  • Power is *not* cheap in most places of the world. Nor is it very clean. Microwave transmission of space based solar collection IS the future. Couple that with wireless conduits and passive radiators for distribution of the energy and mankind will have *finally* achieved an important and historical goal - the harvesting of the suns rays to provide power for the majority. Once the initial infrastructure is up, then power will be cheap, clean AND safe. Very exciting.

  • Don't forget about Fusion! (Score:3)

    by [Zappo] ( 68222 ) on Thursday July 15, 1999 @12:45PM (#1800506)
    There's no need to spend money on this kind of science fiction for a while.

    Fusion research has been languishing for years, obtaining only small slices of the funding pie. Despite this fact, researchers have already developed fusion reactors that generate a controlled energy profit. Granted, there are cheaper ways to boil water today, but the price tag is shrinking.

    Fusion power plants would create no radioactive waste whatsoever. They take in deuterium (a Hydrogen isotope found in so-called "heavy water", which is easily mined right from the oceans), and put out energy, Helium, and other harmless by-products.

    As an aside, note that Helium is a "perishable" resource; the Earth was only born with so much, and it's light enough to escape into space. People laughed a few years back at the "waste" of money in maintaining a national Helium repository, but they shouldn't have. It's a very valuable element for research, and it's disappearing.

    Fusion power would utilize a plentiful resource, and provide energy at enormous efficiency (*much* greater than current fission-based nuclear power), without harming the environment. Yet, it continues to get scanty funding.

    Write your Congressman and encourage spending on a power supply that has already been developed and has no bad side effects. This microwave stuff might be quite helpful for supplying the moon with electricity (of course, so might simple aluminum foil reflectors that simply concentrate sunlight on lunar power cells), but we're still a ways off from needing it there. Perhaps the money that would be saved by replacing our current power plants with fusion-based counterparts could help pay for the next leap ahead in the space program.
  • Impressive numbers, aren't they? But suppose we halve the intensity and need 30,000,000 m^2. 1 km = 1,000 m., so one square kilometer is 1,000,000 m^2. We're talking about 30 square kilometers. Metropolitan Toronto, where I currently work and near where I currently live, covers 10 to 15 times this area. The Greater London Area in the UK covers several times more.

    Or to put it another way, the 401 highway in Ontario, Canada is over 600 km in length and averages over 20 m in width. That means it covers more than 12 square kilometers - in fact it probably covers over half the required area. Yes, replacing one terrestrial power station with an SPS is a large civil engineering project but we already do many bigger ones. It is by no means impossibly or even impractical.

    As I said before, the problems with SPSs are technical - to a certain degree, they look feasible on paper - and, to a far greater degree, economic. It's just not obvious that they could pay for themselves, although a carbon tax could sway that considerably.

    Of all the responses that I've seen here, the one about radio astronomy is by far the most serious and valid concern about SPSs.

    Anyway, it was fun to actually work some numbers here. Thanks for your response.
  • Take a geiger counter to your local nuclear power plant. Record the radiation levels. Do the same at your local coal power plant.

    Guess which one will come out higher?

    If you said "nuclear," you're wrong. Nuclear plants, at least in this country, are shielded to the point of rampant paranoia. You have a better chance of being killed hiding in your basement than you do sitting next to a nuclear plant. Higher levels of radiation there, too.

    The only plants that have succeeded in harming people are those badly-designed pieces of trash in Eastern Europe. Nuclear plants, when well-designed and maintained, are as safe as any other source of power.

  • The US in particular is so wasteful of energy that the kind of money spent on those projects would be better spent on some simple, down-to-earth conservation programs.

    I heard an estimate once that if we converted all incandescent lights in homes in the US to flurescent lights with motion sensors, the energy savings could be in the billions of dollars!

  • What the original poster is talking about is a massive sky hook, I think, which isn't a loop. Check out the link.


    The article that you cite does mention that there has to be a return path; this would mean either a loop or other more exotic methods (such as the plasma gun suggested in the article).


    The setup described is fundamentally different from what the original poster was suggesting, though - the sky hook generates power from the motion of the shuttle through the Earth's magnetic field. The original poster suggested stringing wires from the surface of the Earth upwards, which are stationary with respect to the Earth's magnetic field.


    Any method of power generation that taps motion with respect to a magnetic field is actually just drawing power from the kinetic energy implicit in that motion - i.e., as you generate power, you slow down with respect to that field. For something in low earth orbit, like the shuttle using a sky hook as described, this will eventually degrade your orbit and bring you back to earth. The kinetic energy that you're tapping is also just the kinetic energy that you gave the shuttle during liftoff - so using this kind of scheme for power generating satellites is not useful, as you are just getting back the energy that you put into the satellite in the first place to put it in orbit.


    There are other neat ways that you can use sky hooks, other neat things that you can do with extremely strong tethers, and ways of using tall towers to generate power on Earth, but these are beyond the scope of this discussion.

  • Actually, the best way I found was to build a one-square bump, put 8 waterfall tiles on the 8 sides of the bump, put hydroelectric plants on the 8 waterfall tiles, and put a water pump on top of the bump.

    The big advantage to this was that hydroelectric power plants never wear out, and the water pumps operate at maximum efficiency, because they are surrounded completely by water.

    Plus, no pollution.

    - John
  • Are you saying the problem is that you vaporize the recieving-end equipment, or is the "concentrator" on the sending side?

    If it's the recieving side, why not just heat water on the recieving end and use that for power generation? No doubt it's less efficient... but if it solves the "biggest problem", well...
  • There weren't any conspiracies in my article. All directly observables. You might choose to so label my speculation that the pattern for microwaves will follow the pattern for hydro and the pattern for nuclear. If you are in a mood for more quick ad-hominems.


    Cold fusion may not be "real" but then so far it is just as real as Tokomaks.


    Solar has been practically collected by trees since the Beginning. You may not get the energy density you think you need. Give some consideration to storage media to up the available density. For example, check into the economics and capacity of solutions of Glauber's salt.


    When they start talking about "safe" levels then we'll start hearing about "acceptable" risks. When Rocky Flats plutonium was discovered in backyards in Denver suburbs exceeding the "acceptible" dosage, the acceptable dosage was multiplied by ten. That solved that problem.


    You take a rational tack to discussion, but when you start saying "the only real option" you are backing into the rubric of industry propaganda. Another very real option is more conservation... there is massive room for improvement there. Do all our skyscrapers really need to be lit up at night? Ever seen a nighttime satellite photo of the US? Why are we beaming all those photons up there? How about all those TV tubes to be replaced by flat screens? and so on.


    I'm glad people are thinking of the future. But I wouldn't bet the future on any robots, thanks.

  • There seems to be a lot of controversy in the media and in scientific circles about the safety of exposure to electromagnetic fields. I did find one article online that seemed relatively well-informed (it was well-documented anyway). And it's fairly recent - 1995, iirc. Anyhow, you can check it out here [infobiogen.fr]. As always, try to keep in mind that correlation!=causation. :)
  • Officials at the Pentagon were heard to scream in agony as the installation was turned into a smoldering heap of molten slag.

    Now THAT one is improbable. . . the building is poured concrete. . .now, the PARKING LOTS, on the other hand. .

    Concrete will turn to slag, if you get it hot enough. Even if you don't melt it, you might be able to turn it into the world's largest stone oven. Just before the attack, they'll be wondering why three tractor-trailers full of Pillsbury Cinamon Rolls are being delivered.

  • That is a great solution, but wouldn't work due to atmospheric dispersion. As you recall, the reason why things tend to lose their color if viewed from a mile away, is because the atmosphere tend to bounce light all over the place. So bouncing beams of light from space to a solar collector isn't the answer. The simple truth is Microwave beams wouldn't fry everything in their path. If you all remember your High school physic's class, Radiation is not dangerous. Only certain wavelength are dangerous, because they interfere with certain molecules.

    For instance, when you see colored displays of gas or oil floating on a puddle of water. This is actually radiation interacting with the molecules of the gas, causing them to radiate colored light. The same thing happens to you when you walk too close to a rod of plutonium. The radiation's wavelength tends to be about the same distance apart as the molecules in your body. This causes friction, which causes you to get radiation burns.

    Now mutations is due to a different ball of wax. Mutations don't effect the person that is burned of effected by radiation. It usually will only effect the offspring. This is because the radiation causes damage to the parents DNA. The idea that "Safe levels" radiation would not harm a human, but would hurt a frog or bird is nonsense. Just because a frog lives in water, and a person doesn't has nothing to do with being different when it comes down to what we are both made out of. If radiation is harmful to humans, it's harmful to just about everything that is comparably made up with the same building blocks.

    The only question I have about all of this Microwave business, is where can I place my bag of popcorn to get the best popping action...?
  • There were experiements which showed that we could actually construct nuclear power plants which burned off all of the excess radioactive waste except for a very small amount which isn't even harmful.

    There were experiements which showed that we could have actually constructed nuclear power plants which used HALF as much water as current ones and STILL cool effectively.

    Of course, we can no longer construct new nuclear power plants, so they may end up going down in history as bad just because the older ones produce tons of harmful radioactive waste and we cannot build newer ones which wouldn't.


    Hopefully we can get the kind of power from microwave power plants that would could in SimCity 2000 and 3000. If not, we can always turn back to safe nuclear (The problem is convincing the rest of the world that this is possible.)

    Julian
    --
    eMail: x-virge@shafe.com
    icq: 1521358
    http://www.delanet.com/~jkmissig/ [delanet.com]

  • Re:Oh poo (Score:2)

    by Anonymous Coward
    It seems that when they were trying to get all those plutonium-producing power plants into production (so much for the "peaceful atom") ...
    Of all the topics I see regularly, gun control attracts the largest number of completely ignorant knee-jerk opposition reactions. Nuclear power is #2.

    First, bomb-grade plutonium was only made in Hanford, WA in a facility called the "N reactor", if memory serves. This was a special unit, which irradiated uranium very briefly before reprocessing it to extract the plutonium. Spent fuel from commercial nuclear plants has never been used to make bombs; most of it is still sitting in cooling pools at the plants where it was used. Conclusion 1: Commercial US nuclear power was never associated with bombs.

    Second: The requirement for bombs is that plutonium have very little of the troublesome 238, 240 and 241 isotopes. If you have very much, the bomb is far more likely to "fizzle" than explode. As soon as plutonium is created it begins to transmute from the neutron bombardment, so making bomb-grade Pu requires removing and reprocessing very frequently, on a schedule of weeks. Fuel in commercial US nuclear plants is left in the core, running at far higher power levels than the N reactor, for years. By the time it comes out, it's so chock-full of higher isotopes that no bomb designer would even think about using it. The rate of spontaneous fissions is so high that you can't get a supercritical mass assembled before it takes itself apart (without producing any significant bang). Conclusion 2: Commercial US nuclear power reactors cannot be used to make bomb materials (and still make power). Soviet RMBK's are another matter, but we don't use them.

    Now go, and FUD no more.

  • However, the nice conclusion exists, given this premise, that microwave radiation that misses the target and haphazardly strikes people will benefit the overall IQ level of the country. Maybe we should target some high schools and examine the effects.

    I'd just like it noted that the IQ level will remain exactly the same, with 100 being the median. It's a quotient. As everyone gets smarter, it stays the same. It just takes more to get a "high-IQ" than it used to. Intelligence may increase, and the IQ standard mayrise, but the IQ-level itself (unless no other countries benefit) should remain about the same.
    ~Anguirel (lit. Living Star-Iron)
    "Veni; Vidi; Vi C++"

  • Just in case you are wondering, one reason why environmentalists dislike nuclear power plants is because the water used in the plant for cooling and other purposes is deposited back into the river, or other water source that is used, but at a higher temperature. Now, small changes in temperature in water systems can cause problems in the ecology. Certain fish won't spawn when the temperature of the water changes by only a couple degrees. By dumping this hot water back into the environment can cause damage by increasing the temperature of the water.

    That and they don't like the word radiation.

  • Actually, Environmentalists might well like this idea.

    Burning coal, wood, etc, is not a good idea. For a start, it's not renewable as fast as it's consumed. Secondly, the early Earth atmosphere had no free oxygen. As no new oxygen or carbon has been created, since then, it can be assumed that burning -ALL- fossil fuels and forests, completely, would render the atmosphere to the same state.

    Nuclear fuel produces -enormous- amounts of highly radioactive waste, some of which can be reprocessed in places such as Selafield, England. Even after reprocessing, though, you are left with enormous amounts of extremely toxic, long-lived radioactive isotopes. There are no construction methods yet in existance which can produce a structure that lasts as long as these substances are dangerous.

    As another poster noted, it takes a high dose of radiation to affect you. This is true, for external sources. INTERNAL sources can be very deadly indeed. Wind-borne plutonium can easily be inhaled, as is believed to happen in Seascale, England. Your skin is reasonable protection from alpha particles, but there's no barrier between you and an alpha particle on the inside.

  • Top story tonight: (Score:3)

    by jabber ( 13196 ) on Thursday July 15, 1999 @10:28AM (#1800530) Homepage
    Washington D.C.: (AP)
    Hackers [yeah, I know, but it's a news story] took over the Eastern Seabord Microwave Generation Satellite earlier today, and threatened to redirect the beam at downtown D.C. if Kevin Mitnick was not released immediately.

    Al Gore, the inventor of microwave energy, who singlehandedly placed the aforementioned satellite in orbit, declined, to the dismay of the hackers.

    Officials at the Pentagon were heard to scream in agony as the installation was turned into a smoldering heap of molten slag.

    The hackers, subsequently, threaten to defrost Hillary Clinton; but assure that the Antarctic penguin habitat is not threatened in any way.
  • The ignorance level is very high when the topic of nuclear reactors come up. As an earlier post mentioned, it takes a special type of reactor to produce plutonium. This type of reactor is called a fast breeder, and is very popular in places like china. The CANDU reactor is NOT a fast breeder reactor and does not produce Plutonium. Contrary to the previous statement, the reactor produces radioactive cobalt with no plutonium. The Spent fuel cannot be used in bombs but it is used in radiation treatment for cancer patients. I know this because my father has worked in the pickering Nuclear Generating station, in ontario, for the last twenty years. I have had access to all the good text books.
  • with that much power, the birds wouldn't just start to cook, they'd explode...
    GIF! GIF! This is better than the bug zapper at a picnic!

    This is fscking great! Fried chickens falling out of the sky! Somebody invent a machine to make it rain beer!

    --

  • Heinlein's "Blowups Happen" was first published in Amazing Science Fiction, in 1940 and republished in 1950 in the collection The Man Who Sold the Moon.

    --
  • This is something of a problem not far away from where I live - in Cornwall, England, Radon poisoning is very commonplace, because many of the houses there have stone basements.
  • Guess not. I just went back over what had been written, and that was indeed there. So, ok, what I had thought was a really minor problem is even more minor.
  • look, when I say make the collectors flimsy, I mean like a plastic bag. so what if it gets some holes punched in it? it still retains almost all of it's structural integrity.

    The same goes for the transmitting array. The only reason that these arrays are so rigid on earth is beacause they have to maintain their shape in a gravitational field. In orbit, the transmitter can be as large and as flimsy as you like.
  • Blowups Happen was the first. I'm not even certain that it wasn't in the 30's (but that feels TOO early). It was definitely before '45 (it may have been during the war).
  • What the original poster is talking about is a massive sky hook [nasa.gov], I think, which isn't a loop. Check out the link.
  • "Last time I checked, the latest study on cellular radiation showed that people who used cell
    phones were more imaginative and intellectual than those who did not."

    All that means is that those who are "more imaginative" and "intellectual" earn more money than those who aren't and can afford (or require) mobile phones.

    Statistics can be very dangerous. Apply them with caution.
  • they might be well shielded but some does get through. As an experiment in my EM Fields and Waves class, we took LED's, put a diode across the leads and moved them around the outside of the microwave. guess what. they lit up!!! They were brightest in the upper left hand corner of the glass. That means that radiation does leak from a microwave oven. Maybe not much, but at least some.
    Now imagine this beam, it's going to spread and do similar only with a lot more power.
  • L. Ron (and NASA for that matter) stole the idea from Issac Asimov. One of the stories in "I, Robot" was about a station that collected solar energy and fed it back to earth in a tight beam. It even mentioned the effect it would have if the beam went off even by a fraction of an inch.

    This was written in the mid/late '40's, I believe.

  • But remember that radiation has a tendancy to mutate things, and that humans are not the only thing that can mutate. So can birds, frogs, and airborne bacteria.

    Not all radiation is the same. Unlike radiation from nuclear reactions, RF radiation is not annodizing radiation.

    If you put a frog in a microwave, you're less likely to get a mutant frog than French cuisinne.

    RF basically just bakes things; not much different than getting burned. The nasty thing is that, unlike a good 'ol fire-induced burn, RF heats tissue up from the inside out. So if you're subjected to a high degree of RF radiation, you're likely to be damaged by it before you begin to notice warnings. The amount of damage is deturmined by the power of the RF source, the distance from that source, and how long it took you to notice you're being radiated (length of time exposed to the source).

  • The Arthur D. Little (consulting) Company first championed this idea back in the 1970s, long before Sim City.

    Probably the best place to prototype microwave power transmision would be at the Straight of Belle Ilse, in Canada, between the Island of Newfoundland and Labrador. Vast quantities of hydro-electric power are going undeveloped in Labrador because there is no way to transfer it across the 20 miles of the Straight. Undersea cables won't work because icebergs drag across the bottom of the Straight in winter. Tunneling is prohibitavely expensive due to the hard rock.

    The biggest problem, however, relates to concentrating the power, from whatever source, just before creating the microwave beam. You have lots of megawatts all going through a single point. Any resistance at all -- and you quickly heat your concentrator and vaporize it.
  • Eliminate the Price-Anderson Act, and the civilian Nuclear Energy system would be shut down by the beancounters.

    I'd blame it more on the lawyers and public hysteria. Just as Dow-Corning has been bankrupted by breast implant suits despite the latest scientific evidence claiming no link between implants, the threat of lawsuits is enough to cripple development of further plants. Yet the ones that exist in the U.S. work cleanly and safely, as opposed to coal plants which result in coal miner deaths, hydroelectric plants which disrupt the whole water ecosphere, fuel-burning plants which lead to spills, etc. Maybe solar plants (using mirrors to concentrate the light, so the environmental impact of the collectors is low), wind-powered ones, or salinity or thermal-gradient plants could do better, but not by much.
  • (Imagine, what is the likelyhood that smacking my computer with a hammer will make it work **better**?)

    Accually in fact Microsoft and Intel are setting up a new test lab where they provide and infinate amount of monkeys and infinate amount of hammers and let them hammer out the bugs in computers. Microsoft was quoted as saying "Hey if they wrote Shakespear I bet they can create W2K." While Intel was quoted as saying, "Hey we've already surpassed the laws of physics getting computers to compute a instruction faster than light can travel across your motherboard."

    Oh btw.. I thought ball lighting was real and not just a myth?

  • Re:Radiation & Brains (Score:3)

    by jabber ( 13196 ) on Thursday July 15, 1999 @11:28AM (#1800593) Homepage
    study on cellular radiation showed that people who used cell phones were more imaginative and intellectual than those who did not

    The cause and effect are probably reversed there. I wonder how many intellectual people choose to use cell phones.. :)

    fellow came into the plant (the Nuclear Power Plant) a few years back and set off the alarms on the way in

    Amen! Due to the very vocal and hugely ignorant opposition to nuclear power, most people don't know the facts. FUD is rampant against nukes, and when people hear the word 'nuclear' they think Hiroshima and Chernobyl.

    The facts are:
    • You get more radiation exposure flying from N.Y. to L.A. (4 hours) than you do in 4 years of living next door to a Nuclear Power Plant.
    • You get more radiation getting your annual dental X-ray than you do in a year of living next to a nuclear plant.
    • You get more radiation living in Denver (altitude) than next door to Three Mile Island.
    • You get more radiation from the radon seeping into your (average) basement than you would working in a nuclear facility actually HANDLING the fuel.
    • The coal ash that comes out of conventional power plants as waste is more radioactive than the 'nuclear waste' that comes out of nuclear power plants. But, since the 'nuclear' waste is a product of fission, and not combustion, it is regulated, classified, and branded differently.
    • More people died in the week following the Union Carbide accident in India (early 80's) than will die as a tracable result of Chernobyl. Hereditary problems like Leukemia after three generations not withstanding.


    Nuclear can be very dangerous, when it goes bad. It's quite spectacular. But, it is so regulated, and the people involved are highly aware of the dangers, that the likelyhood of accidents is miniscule.

    I would think that the ignorance level about this field of science would be pretty low here on /., but 'nuclear' carries a deep stigma. Too bad, since it holds tremendous promise for plentiful energy. The U.S. will have to face a fossil crisis in the forseeable future, and by then, we will have to buy power from Canada, or beam it from space. Uranium is cheaper.
  • Remember when nuclear power was being deployed, the hype that surrounded it? The "killer app" of power turned out to be more of a killer than anybody had bargained for. Even if Simcity 2k style things don't happen, are there other things that might? For instance: It stated in the article that the levels of radiation will be "safe." I presume that means safe for humans, i.e. non-lethal dosages. But remember that radiation has a tendancy to mutate things, and that humans are not the only thing that can mutate. So can birds, frogs, and airborne bacteria. While it may seem farfetched, it is entirely possible that these moderately high-powered beams of radiation could create such a high level of mutation in airborne bacteria as to create a "super bacteria," resistant against antibiotics and, most importantly, already airborne. Just some food for thought.... Russell P.

  • I can see it clearly (Score:3)

    by Caktus ( 28195 ) on Thursday July 15, 1999 @09:35AM (#1800606)
    the NASA will be sued for patent infringment really soon by the makers of SimCity2000.

  • Better Source of Info (Score:4)

    by Zppr ( 22841 ) on Thursday July 15, 1999 @09:37AM (#1800612)
    There was an article in the Pittsburgh Post-Gazette earlier this week. Here is an online version:

    http://www.post-gazette.com/healthscience/199907 12solar1.asp

    It's much longer and more informative than the one on the CMU site...
  • Of course, if I really wanted to fry military bases or cities it'd make much more sense (and be much more practical) to buy an old soviet warhead off the black market and park a car a few miles from my target.

    ----

  • Um, hot water gets deposited back into the environment with all kinds of power plants, not just Nuclear ones. Coal burning, Gas burning, Geothermal, they all dump hot water back into the environment (or let it turn to steam, depending on the design). The only ones that don't are Windmills (which have very limited usefulness), Hydroelectric (which also mess up spawning patterns of fish), Solar (dang near useless unless you live in the desert), and Hydrodynamic (which havn't been built yet AFAIK). There might be some other types that don't dump hot water, but they're not practical (or at least not in use).
  • The whole thing has to be a joke! "Safe power levels?" You need a few megawatts to power a small manufacturing plant. A whole city requires thousands of times that. How is billions or trillions of watts going to be safe? Will it ionize the air on the way down? Safe power levels should be less than the intensity of our sun, otherwise imagine bugs under a magnifying glass. So, why not use solar cells? They are proven, yet still costly at about $20,000 to really do a house good.

    The thing would make a wonderful weapon to control the population that is so naughty with that internet porn, encryption, and terrorism. We can't have citizens get out of hand...
  • the only part of your cheerful little story that I don't buy into is the "rocks are radioactive" part of it. Some rocks are more than others. Some air is more radioactive than other air. Was the lichen radioactive due to naturally occuring exposure, such that it would have been the same level a century ago?


    Actually, many types of rocks are radioactive (though something like, say, a spent fuel rod is a few orders of magnitude _more_ radioactive). There is actually a significant health hazard if the bricks and concrete in your basement are made from stone that is high in Thorium. As a part of its decay chain, Thorium becomes Radon, which is a radioactive gas (the heaviest of the inert gasses). This tends to collect in basements, giving you dangerous radiation exposure if you are exposed to it for years.


    This has been happening for as long as rocks have existed on Earth.


    Now, I'm not saying that nuclear power is without its dangers; I'm just pointing out that many rocks are indeed radioactive :).

  • Only as clarification, for the benefit of the under-informed: not directed at the original poster.

    Old plants produce highly radioactive waste due to regulations, not inefficieny. The result of fission on U238 can be enriched, and reburned, repeatedly, until what remains is less readioactive than the granite under our feet.

    However, the process that does this, can also be used for producing weapons-grade fissionable materials, and the NRC/DoE/DoD don't want that tech to be in the public sector.

    It is NRC regulations that require that high level redioactive waste be burried in mountains, at significant cost, rather than used for fuel.

    Consider the analogy of pig farming. You grow corn to feed your pigs. Your pigs make waste.

    You can use the waste to fertilize your corn, and to produce methane. You can use the methane to power generators to make electricity. You can use the electricity to run lights, ventilators, water pumps and the like. You can deliver the water to the pigs, and to irrigate your corn crop. You can then sell excess corn to buy more pigs.

    But, the waste smells bad, so the government makes you bury it.
  • The site is slashdotted already, seconds after being posted here. That has left me with a ton of questions.

    I wonder how they are going to focus a beam with hundreds of megawatts of power in it down through the atmosphere. There are all kinds of engineering problems to overcome, such as dispersion of the beam in the atmosphere, reflections and deflections of parts of the beam by atmospheric winds, compensation for changes in the temperature and humidity of the air.

    How large a target will the beam be aimed at? Presumably a field several miles across full of receiving antennas. The antennas near the center of the beam will receive full power, while antennas at the edge would receive only a few percent.

    How do you keep birds from flying into the beam area, and what happens to people living near the receiver? Do you move all the citizens out of the area, and declare it a danger zone? How do you shield the operation engineers working near the site?

    I think NASA is hoping to get a small pilot program up and testing in the next 20 years or so. There is a lot of research left to be done.

    And the SimCity beam was one of the best. Bzzzzzzzzzzzzzzzzzzzzzzz.

    the AC

  • Radiation & Brains (Score:5)

    by debrain ( 29228 ) on Thursday July 15, 1999 @09:43AM (#1800642) Journal
    Last time I checked, the latest study on cellular radiation showed that people who used cell phones were more imaginative and intellectual than those who did not.

    That's somewhat interesting, but I've never seen the case study myself, and wonder what kind of control group they used -- maybe people who use cellular phones are simply more intelligent and imaginative and use phones because of that. My interpretation of what I was told (by an MD) was that the cellular radiation stimulates activity in regions of the brain where without the cell phones there would be none.

    However, the nice conclusion exists, given this premise, that microwave radiation that misses the target and haphazardly strikes people will benefit the overall IQ level of the country. Maybe we should target some high schools and examine the effects.

    Note: It has never been conclusively shown that cellular radiation increases the chances of brain tumours. I worked in a nuclear power plant -- the fear of radiation is greatly exaggerated, I assure you. Live in the average Ukranian basement for 8 months and you'll exceed legal Canadian doses of radiation (legal, not lethal :P).

    Radiation becomes a problem when it is in the form is acute doses -- high exposures in a short period of time. Just for the sake of a story: a fellow came into the plant (the Nuclear Power Plant) a few years back and set off the alarms on the way in. It was surprising to discover that the source of the radiation that set off the alarms was in his belly -- a result of him eating Caribou meat over the weekend when he went hunting. The Caribou were eating lichen off rocks, and rocks are radioactive, and hence the Caribou meat was releasing enough radioactivity to set off the alarms at our wonderful Nuclear Power Plant.

  • Not the arcos!!! Noooooo

    Oh well, I'll just go to SCURK and put them back, hehehe....
  • Anyways, the ideal power source would be to string up a very long conductor from the earths surface to 100 or 200 kilometers into space. Hook up a small weight on the end to keep it in geosyncronous orbit and then reap the electricity coming off it in droves as it cuts through the earths magnetic field.


    Um, no.


    Firstly, in order for your weight to pull the wire outward, it has to be at or above the altitude at which geosynchronous orbits are normally found - about 40,000 km (about 25,000 miles). That's more than 100 or 200 km. The _wieght_ of this wire will be very substantial - enough that the tensile strength on the wire is far greater than any material currently in use can sustain. Find materials that can take these kinds of stresses, and we will be able to do far more interesting things than generating power.


    Secondly, I think you mean the sun's magnetic field (carried outwards by the solar wind). The earth's magnetic field rotates with the earth - your wire will not be moving with respect to it, and so will generate no power from it. The sun's magnetic field will give you power, but it's open to question how much (could someone with the required numbers and background provide an estimate, please?).


    Thirdly, you need a loop of wire to generate power from a magnetic field in this manner, not just a single wire. If you had magical cable that could withstand the required stresses, this could be built in the manner you describe, but that's a pretty big "if".


    In summary, there are a lot of other methods that can be implemented _now_ that are more practical.

  • Nuclear fuel produces -enormous- amounts of highly radioactive waste


    A minor quibble here - the amounts of waste produced are actually quite small. The energy density in nuclear fuels, even when burned in conventional, inefficient fission plants, is between four and five orders of magnitude higher than the energy density of fossil fuels. Correspondingly _less_ fuel is needed, and so you wind up with between 10,000 and 100,000 times less waste material than with fossil fuel plants.


    Instead of a billion tonnes of coal burned to produce three billion tonnes of CO2, for instance, you'd get ten thousand tonnes of uranium oxide producing ten thousand tonnes of plutonium oxide and mixed nasty isotopes.


    This is still not negligeable, but you could store this in a gymnasium with room to spare. Compared to a _billion_ tonnes of coal.


    What we actually need is a reliable way of storing _small_ amounts of waste for very long periods of time. That, or transmuting it all into something with a shorter half-life (expensive).

  • >Just put the energy in a really big Tesla Coil.

    Cool! Now we're at C&C Red Alert! I REALLY liked the Tesla Coils's. ZAP!


    jf
  • He had ideas of placing a nuclear reactor in space, then beaming the energy down to the globe. I also seem to remember something about placing a black hole in orbit and harnessing the power generated by matter/antimatter collisions...

    Actually, there's more information about this at NASA, in an article entitled Integrated thin-film solar power satellite [nasa.gov]. It goes into more detail about the part we care about -- the satellite and its uses -- instead of the robot being developed at CMU to help construct the darn thing. It even has a couple of MacPaint-like pictures of what this thing might look like.

    What about (as someone else mentioned) flying objects which end up in the path of the beam? Even if it would pass through us, it would get absorbed by rain clouds (making it just as effective as those solar panels we were all promised in the late '70s), or worse yet, by birds, airplanes, and other flying objects... Certainly, the danger of the solar collector crashing to the ground is less than that of an orbiting nuclear reactor or black hole...but it still seems a bit unsafe. For this thing to be useful at all, it's got to transmit multi-megawatts of energy from point A to point B, and that energy will inevitably get absorbed by SOMETHING in the area. And if the levels are low enough to be "human-safe," then they're barely going to be able to light a bulb, let alone run something useful (like a section of a power grid).

    That's why NASA is looking at using these things more to transmit power to lunar bases, Mars missions, and the like. In these controlled environments, something like a giant orbiting solar panel make a heck of a lot of sense:

    However, it is quite likely that some of the most important applications, and certainly some of the initial applications, will be in space. Here atmospheric attenuation does not limit the frequency choices and transmission distances may be less. Further, because of the high total mass of the power systems (including storage, PMAD, thermal control and structures) and the high transportation costs, existing power sources for use in space provide power at a considerably higher effective price ($800/kW-hr) than terrestrial power sources ($.10/kW-hr)

    P.S. Anyone reading this remember when parts of your 'Net link were transmitted by microwave? Our link in college used to go down regularly, and a call to MIT confirmed that their microwave link to BU (or was it BC? I can never remember) was down due to rain. Sure adds another dimension to the concept of "Internet Weather Forecasting!" :)

  • It stated in the article that the levels of radiation will be "safe." I presume that means safe for humans, i.e. non-lethal dosages.


    There are different kinds of radiation. Just
    because people call microwave ovens "nukes"
    does not mean that they actually use nuclear
    radiation.


    Quick science review: There are two main types
    of "radiation" in this context: that caused by
    acclerated particles (alpha and beta radiation,
    produced by fission and to a lesser degree
    fusion) and electromagnetic radiation.


    Hopefully you know that all electromagnetic
    radiation is essentially the same thing. It's
    a vibrating electromagnetic wave, the only
    important things are the frequency and the
    intensity. High-frequency stuff (like gamma and
    x rays) are "ionizing"; even a little of it can
    knock an electron free of an atom. If this
    happens to DNA, presto, you have a mutation.


    Visible light and microwave radiation are "non-
    ionizing". Unless you have a lot of it,
    it won't do damage to individual molecules. You
    don't want to stand in front of a powerful
    antenna, but that's not because it's actually
    ionizing atoms in your body. It's just dumping
    energy into it, which shows up as heat. You can
    get cooked that way.


    Now, cells put under stress do spontaneously mutate from time to time. As I
    understand it, this is why sunburn can cause
    skin cancer; I don't think that ultraviolet light
    is considered ionizing.


    Bacteria might proliferate in a warm area (such
    as a proposed microwave power receiever would
    be) but that's no different from fish accumulating
    near nuclear power plants because they like the
    heat from the cooling water.

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