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Focused Microwaves Could Enable Wireless Power Transfer

Soulskill posted more than 5 years ago | from the pushing-pinpoint-power-production dept.

Power 180

esocid alerts us to news out of the University of Michigan, where physics researchers have found a way to focus microwaves to a point 20 times smaller than their wavelength using a new 'superlens'. Such resolution was thought to be impossible until recent years, and it could bring about the capability to transfer power wirelessly. "No matter how powerful a conventional lens, it cannot focus light down to more than about half its wavelength, the 'diffraction limit'. This limits the amount of data that can be stored on a CD, and the size of features on computer chips. The new lens is a 127-micrometer-thick plate of teflon and ceramic with a copper topping. 'The beauty of these is that they're planar,' Grbic says, 'they're easy to fabricate.' The lenses can be made through a single step of photolithography, the process used to etch computer chips."

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We tried that (1)

zoomshorts (137587) | more than 5 years ago | (#23204056)

Back in the 1960's. Diode grid to rectify the beamed power. Bad idea.

Re:We tried that (5, Funny)

Kuukai (865890) | more than 5 years ago | (#23204100)

I know what you mean, messing with wireless power is a seriously bad idea. Tesla tried it too, and look what happened to him. He's DEAD!

Re:We tried that (1)

Cyberia (70947) | more than 6 years ago | (#23205318)

No, you have this all wrong! This is all a ploy by Orville Redenbacher to improve the bottom line.

1. Develop a more powerful microwave emitter
2. Add 30 extra seconds to cook time
3. Profit! (By people burning more popcorn faster)

    "But the bag said 2 1/2 nanoseconds... and now look at this charcoal..."

Re:We tried that (0)

Anonymous Coward | more than 5 years ago | (#23204110)

The potential growth for this technology is explosive.

Or maybe I'm just thinking of the people who wander in between the sender and reciever...

Re:We tried that (1, Insightful)

Anonymous Coward | more than 6 years ago | (#23204206)

Do you think perhaps that the power levels we are discussing here are somewhat lower? Just maybe things take less power these days? Rectennas were meant to deliver grid-power rectified from microwave masers in orbit... I think here we are talking about a few mW to power a gizmo. Sheez.

Re:We tried that (3, Interesting)

CRCulver (715279) | more than 6 years ago | (#23204248)

It's interesting to consider whether power beamed down from orbit even has much of a future. If space elevators ever become a reality, it seems much safer just to have power from orbital solar arrays wired back down the elevator than beam it, where anything passing through could be fried.

Re:We tried that (4, Insightful)

joto (134244) | more than 6 years ago | (#23204470)

Depends on how much the power is needed, and how soon. The space elevator seems like it's a long time away, still in need of new materials to be invented, and so on. On the other hand, solar power in space is feasible now, at least technically.

Without power people die. So the risks of catastrophic failure of microwave power transmission from space, must be weighted against the possibility of many people not getting electricity. It might be safer to build powerplants now, than to wait for a hypothetical space elevator.

Re:We tried that (3, Funny)

WaltBusterkeys (1156557) | more than 6 years ago | (#23204544)

Didn't we try this in Sim City? Look how well that worked out.

Re:We tried that (4, Interesting)

NeverVotedBush (1041088) | more than 6 years ago | (#23204534)

The issue with wires is that you will have IR drop and I^2R power losses. If you make the wires thicker to cut the resistance and losses, you have now made the wires heavier. Plus, you have to somehow support the weight of all that wire which means the tensile strength must be huge.

On the other hand, if you beam the energy down, you will have much lower losses provided the atmosphere is transparent at the wavelength you use to send the energy. All you will get from beam spread will be a lower energy density but the same total amount of energy (aside from absorption and scatter losses) will be available.

Beaming power down is probably a much more efficient way to go depending on conversion losses at the source, the scatter and absorption losses, and the conversion losses again at the receiver.

I don't know about the efficiencies and losses of beaming but would guess they would be much less than however many miles of cable would be required and would bet the cost would be lower as well.

You would just need to make damn sure you switch the beam off if it quits tracking the target receiver. Bu as the other person commented, I think this isn't intended to beam power from space.

Re:We tried that (2, Interesting)

Anonymous Coward | more than 6 years ago | (#23205092)

Actually, wire losses fall off as 1/e^(decay*r); it's free space where losses go as 1/r^2 when you get to the antennas' far field, but your overall point is still valid.

For *any* wire, even if it was made out of a really good conductor like gold, there is always some distance where the losses become greater than that of wireless transmission at the same distance.

Re:We tried that (4, Informative)

NeverVotedBush (1041088) | more than 6 years ago | (#23205236)

What I was referring to was current squared times resistance which equals power. The R was resistance and not radius. V = I * R, and W = I * V. Therefore, W = I * I * R.

Likewise, the IR drop is also just Ohm's law which equals voltage. The resistance will have some value per unit length and the longer the length, the more voltage drop.

The way to drop the current, so the I^2R (watts) losses can be reduced is to increase the voltage. But as you go to higher voltage, and higher altitude, where the air pressure starts getting low enough to support a plasma discharge, insulation starts getting important which just leads to more weight, etc.

Re:We tried that (2, Interesting)

beav007 (746004) | more than 6 years ago | (#23205470)

So. What about beaming it down the elevator umbilical cord, using optic fibre?

Re:We tried that (1)

Original Replica (908688) | more than 6 years ago | (#23204588)

It's interesting to consider whether power beamed down from orbit even has much of a future.

I'm not sure solar power from orbit is going to be that good an idea as a primary world power source, at least until global warming is already largely solved. I may well be over simplifying things, but isn't the basic problem of global warming a matter of too much energy in the biosphere? How is adding more energy to the equation going to do anything but make it worse? I know that ideally it would replace hydrocarbon fuels and greenhouse gas levels would plummet, but during the transition time where we would still have the greenhouse gases but adding additional power (heat) to the biosphere it would seem to be pushing us all too close or over a tipping point, like the release of undersea methane. [findarticles.com]

Re:We tried that (2, Funny)

NeverVotedBush (1041088) | more than 6 years ago | (#23204646)

I don't see how it is that different from burning carbon-based fuels or running nuclear power plants. Both of those release heat energy back into the atmosphere/biosphere as well.

Beaming the power in, where some of it (depending on efficiencies in transmission and use) would be turned into heat energy, would actually release less energy into the biosphere than nuclear or fossil fuels where the inefficiencies in power production itself, since it occurs in the biosphere, release additional heat energy.

Re:We tried that (1)

FooAtWFU (699187) | more than 6 years ago | (#23205020)

Carbon-based fuels such as oil and coal (and derivatives) release, um, carbon dioxide, rumored in certain circles to be some sort of a "greenhouse gas". This stuff apparently traps the daily dose of solar heat far in excess of the actual heat which is produced.

We're talking the Sun outputting ~174 petawatts here, people. Peta. (And not the "people eating tasty animals" PETA either). Fossil fuel waste heat is about 13 terawatts. .007% It really hardly matters at all next to changes in the thermal permittivity of the atmosphere.

(Also note that incoming solar energy tends to be of forms and frequencies that pass the atmosphere more readily than the outgoing so don't worry that the effects will cancel out or anything.)

Re:We tried that (1)

NeverVotedBush (1041088) | more than 6 years ago | (#23205282)

Um, I know that carbon-based fuels lead to carbon dioxide emissions.

The point I was replying to was that beaming energy down to the planet added energy to the biosphere.

The point I was making was that any method of producing energy terrestrially will have losses associated with it and that will release additional energy in the biosphere.

Collecting energy in outer space, and converting it to some beamable form of energy will have any inefficiencies in that process occur in outer space and the heat generated won't be added to the biosphere.

Obviously, the receiver conversion will have inefficiencies and that waste heat will be in the biosphere, as will all the inefficiencies in transmission and ultimate use.

In other words, I was saying that beaming in would add less heat than converting the same amount of end use energy as current methods. I never said anything about carbon dioxide - which as you say, just makes fossil fuels that much worse.

Re:We tried that (0)

Anonymous Coward | more than 6 years ago | (#23204652)

We aren't at the level of Puppeteers just yet.

Re:We tried that (3, Interesting)

node 3 (115640) | more than 6 years ago | (#23204684)

The energy in question is coming from the sun, and was going to enter the biosphere anyway.

To a certain extent, the effect will be the exact opposite of what you are thinking, as the sunlight would have most assuredly heated the land, sea and air, but beamed down to the electrical grid, it will be stored in other forms, such as the potential energy of a high-rise building, or in places where the increased warming isn't terribly important, like the area immediately around a ski lift.

Re:We tried that (3, Insightful)

Jeremi (14640) | more than 6 years ago | (#23204796)

I may well be over simplifying things, but isn't the basic problem of global warming a matter of too much energy in the biosphere?


No, the problem is that carbon dioxide is acting as a blanket, trapping too much heat beneath it.


How is adding more energy to the equation going to do anything but make it worse?


It's not a heat beam, it's a microwave beam. There's a big difference between the two. The amount of heat generated by the beam when it reaches the receiver would be insignificant, and it would generate no heat when going through the atmosphere, because the wavelength chosen would be one that is transparent with respect to air. So the net effect would be practically zero added heat. (Even if you count the heat generated by the motors powered by the resulting electricity, it's still insignificant compared to the heat trapped by CO2 in the atmosphere) And if we use that device to replace traditional fossil fuels, then its net effect would be a significant reduction in CO2 output.


There are good reasons why in-orbit solar power isn't a good idea at this time, but your reason isn't one of them.

Re:We tried that (1, Insightful)

Anonymous Coward | more than 6 years ago | (#23204830)

isn't the basic problem of global warming a matter of too much energy in the biosphere?

No. The total world energy consumption is roughly 15 TW per year. In comparison, the total solar energy striking the Earth is just over 150,000 TW. Therefore, replacing our entire energy consumption with external sources only increases the energy flux striking the Earth by about 0.01%.

Better than that. (3, Insightful)

Ungrounded Lightning (62228) | more than 6 years ago | (#23205234)

... replacing our entire energy consumption with external sources only increases the energy flux striking the Earth by about 0.01%.

Actually, replacing ground-generated electricity with space solar power REDUCES the heat load.

First: Ground generated electricity is made with big heat engines, limited by the carnot cycle. In addition to the heat released by using the energy, there's the heat released on the cold side of the heat engine. The total is a lot more than you bought and used.

But with space solar power the cold side of the heat engine is in space, radiating toward the sky (with it's black body temperature of 4 degrees absolute). The dumped heat misses the earth. All you heat with is the useful power and a few percent losses. (The sky-to-ground system is estimated to run in the range of 90% efficient and only part of its losses are on the ground.

But far more significant: Fuel-driven ground generators release carbon dioxide, which continuously traps solar power as heat until it's eventually scrubbed from the atmosphere decades or centuries later. That is a big multiple of the useful power actually delivered. No fuel burned on Earth, no CO2 pumping the greenhouse.

The main problem will be keeping us from sliding into an ice age over the next 400 to 1,200 years. (According to one model the current interglacial peaked at about the dawn of agriculture and we've been essentially regulating the earth's temperature as the "furnace" output has been curving down for the last 6,000 years or so, with a slight bump since industrialization. Stop the CO2 and we'd quickly crash back onto the steepening slope of the cooling curve.) But that takes decades to centuries. So we can decide what to do about it in a few generations, when we start to get below the old "regulated" temperature.

One nice thing: If we need to bring in more heat from space we'll have the infrastructure to do it. B-)

Re:We tried that (1)

khallow (566160) | more than 6 years ago | (#23205250)

Heat from human activity is an insignificant power source. It is many orders of magnitude lower than the solar influx. My take is the drop in albedo from dark roads, parking lots, and roofs are larger heat sources than heat from human activities.

Re:We tried that (1)

Ihmhi (1206036) | more than 6 years ago | (#23204932)

I don't see how a plane getting burned by a microwave beam is any different than a plane running into the tether of an orbital elevator. What, they can *see* the tether? Not in low visibility.

That particular danger is no risk to planes so long as warning beacons are established. That worst that is going to happen is that a flock of geese is going to get sauteed in 3 seconds.

If you think about it, this would actually be better for us anyway. I'm sure some idiot would get it into their head to try and run a plane into an orbital tether and take down the "Great Satan" that is clean solar energy. How are they going to take down an microwave array? I guess they could run a plane into the ground station, but they sure as hell aren't going to take a 747 up to a satellite in orbit.

Re:We tried that (0)

Anonymous Coward | more than 6 years ago | (#23204212)

I tried it too back in the 90s. Except that the damn rays kept on turning the neighborhoods into live BBQ sessions' locations.
 
I had to clear out a 5 tiles radius around the plant at the end.

Actually it was a very GOOD idea but NASA blew it. (5, Interesting)

Ungrounded Lightning (62228) | more than 6 years ago | (#23204364)

Back in the 1960's. Diode grid to rectify the beamed power. Bad idea.

Actually it was a very GOOD idea. But NASA blew it.

The plan was to site solar power satellites in geosync orbit and bring the power back via microwaves.

Unlike microwave ovens (which are tuned to a frequency that is strongly absorbed by water), these would be tuned to a frequency where water - clouds, rain, birds, cows, people - is essentially transparent. This is good both for getting the power through the atmosphere and avoiding rains of roast duck.

I could go into detail on why there's no problem from the millimeter waves, but that would take time. Short form: System failures defocus the beam so much it becomes just radio interference in directional antennas pointed at the satellites. Even when fully focussed it's not an issue for tissue: You can grow crops and graze cattle under the (rather spindly) rectennas, so they don't even use up the chunk of land they're on.

Benefits:
  - Enough power to completely replace fossil fuel AND nuclear plants and absorb forseeable energy use expansion for decades.
  - 'Way cheaper, too. (Even at '60s fuel prices.)
  - Essentially no pollution at ground level.
  - Bootstraps a space program that can then move other manufacturing processes, and THEIR pollution, off the planet as well.

NASA blew it by doing a study that purported to show it would be too expensive. But they did that by splitting the design teams for the rockets and the power plant. The power plant designers made a turbine very large to get a couple extra percent of efficiency. Then the rocket designers came up with a heavy lifter sized to take the biggest piece. Result: Enormous rockets with few trips to ammortize the design/construction costs, rather than moderate sized ones with many trips. Cost skyrockets versus a properly integrated design with a small turbine and a fleet of smaller lifters.

Re:Actually it was a very GOOD idea but NASA blew (0)

Anonymous Coward | more than 6 years ago | (#23204650)

Are you serious? You're smarter than a Nasa study?

I'm going to assume you are.

Then you can certainly explain how 1300 watts per square meter and putting it...IN FUCKING OUTERSPACE...is better than 1000 watts per m^2 on the ground.

Sounds fun doesn't it! Just like hyperdrive sounds fun on star trek, and I wish I had the force, but in reality it doesn't make a lot of sense.

Re:Actually it was a very GOOD idea but NASA blew (4, Insightful)

ZorbaTHut (126196) | more than 6 years ago | (#23204692)

I don't know if he's correct, but even a small amount of thought should show you a lot of possible ways.

* No exposure to the elements, thus reduced maintenance cost from wind/weeds/corrosion
* No land cost
* No clouds, no day/night cycle
* Cost is based on weight, not on land, potentially allowing for use of extremely large light cheap panels instead of smaller denser more expensive ones

Does it make up for the difference? I couldn't say. But there's four ways in which space beats land in terms of efficiency.

Re:Actually it was a very GOOD idea but NASA blew (1)

Ranzear (1082021) | more than 6 years ago | (#23204838)

I think space is much less habitable for delicate solar array than this cushy, climate-controlled rock with plenty of surface to spare.

Why not put solar arrays on the poles? Maintenance in the offseason.

Re:Actually it was a very GOOD idea but NASA blew (1)

ZorbaTHut (126196) | more than 6 years ago | (#23204904)

Wind. Daily drastic temperature shifts. I don't know if the poles snow at all, but if they do, you'll have to rig up a system to clear the snow off. Wipers have moving parts which tend to jam and break, heating coils would massively exacerbate the temperature-shift problem. Getting the power to someplace useful - are you going to run a giant cable to Canada? If so, what kind of maintenance is it going to need? Or are you going to bounce the power off a satellite, doubling transmission losses compared to the satellite-based systems and requiring a satellite launch anyway?

Space has its own set of problems, of course. Radiation, magnetic fields, and if you go into darkness at all, an entire new set of temperature-shift issues. But there's far less atmosphere, and therefore heating the entire spacecraft during "night" to eliminate temperature shift problems is much more feasible. (I don't know if it [i]is[/i] feasible, note. It's just less ridiculous.)

I'm not saying that either of these is better, again. I'm just saying that they involve different sets of challenges, and that without quite a lot of knowledge of the problem (which I certainly don't have) it's hard to say which is actually worse.

Re:Actually it was a very GOOD idea but NASA blew (1)

MikeBabcock (65886) | more than 6 years ago | (#23204918)

Two words: Space junk.

We'll be up there replacing solar panels regularly, guaranteed, because of space junk.

Geosynchronous satellites don't move out of the way of space junk so well, being well, relatively stationary (relatively) :-)

Re:Actually it was a very GOOD idea but NASA blew (2, Insightful)

ZorbaTHut (126196) | more than 6 years ago | (#23204956)

Three points. :)

First off, geosynchronous may or may not be a good idea. Geosynchronous orbit is painfully expensive, and in most cases it's far more cost-effective to launch a large number of low-orbit satellites. If receiver stations were placed in various locations, satellites could just lock on to a different receiver as they pass over the globe. (On top of this, it means that a lot of different countries could theoretically buy energy at various times from this - it might even be worth placing receiver stations in third-world countries, since it's not like the power would be doing anything useful if it wasn't getting sold.)

Second, space is really really big. Even with the space junk we have up there already, impacts are spectacularly rare. It's a factor, but it's not a huge factor.

Third, why fix the broken panels? I highly suspect it would turn out to be cheaper to simply launch more satellites, at least until we have some kind of orbital repair bots. As long as the core electronics are reasonably redundant, the thing can stay up there as long as it's got a single working panel.

Re:Actually it was a very GOOD idea but NASA blew (2, Insightful)

Ungrounded Lightning (62228) | more than 6 years ago | (#23205168)

Are you serious? You're smarter than a Nasa study?

I don't claim to be (though I did work on NASA projects and have some idea where I stand among the mind power of the rocket science community B-) ).

But I'm not talking from my own work. I'm summarizing what I heard from some of the braniacs who were paying attention to the problem.

Then you can certainly explain how 1300 watts per square meter and putting it...IN FUCKING OUTERSPACE...is better than 1000 watts per m^2 on the ground.

Well for starters:
  - No clouds, rain, or snow.
  - No atmospheric attenuation.
  - No night.
  - No seasons. ("It's always noon on midsummer's day.")
Those are good for about a factor of seven (depending on the earthbound site you're comparing).

More importantly:
  - No gravity (except tides).
  - No wind (except solar wind).
  - No oxidizing atmosphere.
  - No corroding water and waterborne ions.
This enormously reduces the structures required.

That would be an enormous reduction in the amount of material needed to make and mount solar panels. Most of their structure is to protect them from the elements and support them against gravity and wind.

But we're not talking photovoltaic solar panels here. We're talking a steam plant, with the steam generated in pipes and mirrors and condensed by pipes with black cooling fins in the mirrors' shade.

With no gravity, wind, and the like, building square miles of parabolic-cylinder solar mirrors is trivial. Making them of aluminized mylar "spaceblanket" material supported by glued-together toothpicks and cobwebs would be a massive overdesign. Virtually all of your mass is the boiler and condenser pipes and the wisp of structure that keeps them straight and properly arranged and oriented as they heat and cool unevenly.

Now it might prove even better to build some film solar panels - especially if you're doing it in space by vacuum deposition of films on some flimsy substrate with an unlimited supply of hard vacuum for free. But sending up bundles of pipe, rolls of wispy plastic, and a flimsy support structure to expand in space. wrap with the mirror film, and aluminize once it's in place is a well understood and (as space stuff goes) inexpensive process.

The power plant is a moderately small lump of machinery suitable for assembling in orbit and charging with a small amount of water.

The transmitter array gets deployed much like the mirrors - but more simply. (It doesn't have to be accurately, or even consistently, spaced. The transmitters are synchronized and the array is focussed by a pilot beam from the ground site, computing the complex-conjugate of the incoming carrier's waveform to focus the beam on the antenna surrounding the pilot transmitter. Lose the pilot and they go incoherent - spreading the energy about equally through the surrounding sky, of which the entire facing side of Earth is a small fraction. (And you can modulate the pilot with an encrypted spectrum-spreader so nobody can steal the power or redirect it to another target.)

Re:Actually it was a very GOOD idea but NASA blew (3, Insightful)

Jeremi (14640) | more than 6 years ago | (#23204706)

NASA blew it by doing a study that purported to show it would be too expensive.


Actually, NASA's study got it exactly right. The amount of solar-collecting material you'd need to place into orbit is large enough that you'd spend a lot more energy and money getting it into orbit then you'd ever get back from it once it was functional. Things may have improved since then (more efficient rockets, lighter solar panels, etc), but I doubt they've improved so much as to make the plane feasible yet. I'd re-do the feasibility studies after the space elevator is up and working, getting enough mass into orbit will be a lot cheaper then :^)

Re:Actually it was a very GOOD idea but NASA blew (0, Offtopic)

GeneralCC (1206630) | more than 6 years ago | (#23204852)

I have no problem with this idea. It is intriguing. My problem is with the energy system of America as a whole. The fossil fuel market is drawing quickly to a close. Now many people want to replace their gas with hydrogen. I completely disagree with hydrogen for three reasons. First hydrogen is more volatile than gasoline and it has serious storage problems (Ask the Hindenburg). Secondly, electricity is wasted in the electrolysis process (electrolysis is around 66% efficient). Lastly and most importantly it is exactly what oil companies want. They want an infrastructure they can control. A battery/ electric car is in my view undeniably the best option. Don't let any corporations catch you saying that though. I think renewable energy is a great idea in the short run. But growing energy needs will ultimately eclipse renewable energy. Or at least there will be some minimum that energy will always cost more than In 2005 a nuclear reactor in Arizona produced more energy than all solar and wind plants that year. About 10% of American power in nuclear power. In the United States for the past 30 year since Three Mile Island there has been a public schizophrenia of nuclear power. Only one new reactor has been approved since 1979. France is the world's leading energy exporter and about 75% of their energy is nuclear energy. They have employed new technology that reduces nuclear waste by 90%. Really nuclear waste is benign. The amount of toxic waste created by producing solar cells for renewable energy eclipses the amount of nuclear waste generated. As for nuclear meltdowns, the temperature of a uranium powered critical reactor regardless of design will never eclipse a certain temperature. The casings of the reactor can withstand this temperature. Persons living next door to a reactor encounter less radiation from the reactor each year than they do from continental plane flight. Contrary to popular belief nuclear power is both safe and economical. Ultimately nuclear power is the key especially when considering space travel within the solar system. If you are familiar with antimatter, it is not an available resource, but can be created. Eventually in many years antimatter will be the only viable option for interstellar travels. Space travel is something that would stimulate the economy. Every dollar spent by NASA makes seven times its value in GDP. There are trillions of dollars of natural resources on a single asteroid. The moon contains Tritium that is almost a purely burning nuclear fuel. So space is worth the effort. This is off topic. But replacing nuclear power I don't think is wise. I do believe that this satellite solar beam technology is worth pursuing.

Re:We tried that (1)

Rival (14861) | more than 6 years ago | (#23204648)

Of course -- Teflon and ceramic with a copper topping, to make capacitors that interact directly with electromagnetic waves -- it's all so simple!

Seriously, though, this is wild. Does this sound like something out of a sci-fi novel or what? And according to the article, one of these "lenses" has been successfully made.

Unbelievable. But very cool!

Ant colonies, beware! (2, Funny)

Bob(TM) (104510) | more than 5 years ago | (#23204074)

What is it with geeks and magnifying glasses?

Re:Ant colonies, beware! (4, Funny)

somersault (912633) | more than 5 years ago | (#23204144)

We're just trying to work out all the bugs :p

Misleading title (3, Insightful)

meatmanek (1062562) | more than 5 years ago | (#23204108)

While it's nifty that they can focus EM radiation to a smaller point now, I'm not following how this will enable wireless power transfer [wikipedia.org] .

Re:Misleading title (2, Informative)

Ungrounded Lightning (62228) | more than 6 years ago | (#23204388)

While it's nifty that they can focus EM radiation to a smaller point now, I'm not following how this will enable wireless power transfer.

Smaller rectennas. Higher efficiencies. Less land use for the receiving end. Lower cost as a result of all three.

Less power beam soaking into other things, too, which means you can find a receiving site closer to the load and shorten the transmission line.

Tesla, FTW! (-1, Redundant)

corifornia2 (1158503) | more than 5 years ago | (#23204118)

Tesla, FTW!

Superlens = spillover = irradiation (5, Informative)

G4from128k (686170) | more than 5 years ago | (#23204130)

What I remember from studying this technology 15 years ago was that it was possible to create a beam sharper than the diffraction limit, but the result was diffuse spill-over. That is, one could create an extremely sharp main lobe in the beam pattern, but one had to suffer higher side-lobes. That's OK for imaging and lithography applications -- the spill-over is diffuse enough not to cause too many problems. But for power applications it means both inefficiency (power lost to the side lobes) and irradiation for people who think they aren't in the beam.

Re:Superlens = spillover = irradiation (1, Informative)

DougBTX (1260312) | more than 5 years ago | (#23204164)

Here's what the diffraction pattern [sciencemag.org] looks like, quite impressive.

You may have forgotten... (3, Informative)

MichaelSmith (789609) | more than 6 years ago | (#23204230)

The content you requested requires a AAAS member subscription [...]

Re:You may have forgotten... (0)

Anonymous Coward | more than 6 years ago | (#23204422)

Go sign up for an account with your local public university library. Problem solved.

Re:You may have forgotten... (3, Funny)

Profane MuthaFucka (574406) | more than 6 years ago | (#23204984)

Problem: my local public university was invaded by physics theorists and is now non-localized. Now what?

Re:Superlens = spillover = irradiation (0)

Anonymous Coward | more than 6 years ago | (#23204318)

Geez, the least you could do is share your login.. :)

No registration required (2, Informative)

dietlein (191439) | more than 6 years ago | (#23205316)

Here's what the diffraction pattern [sciencemag.org] looks like, quite impressive.

Here is their other paper [arxiv.org] (no registration required) on the design of these near-field focusing plates. The results are quite impressive indeed; there are no sidelobes or spillover to speak of. The concept to understand here is that the final radiation pattern is designed (it's the starting point, in the math), and the required focusing plate geometry is the result of solving the equations in the paper.

Irradiation, perfect! (3, Funny)

node 3 (115640) | more than 6 years ago | (#23204766)

irradiation for people who think they aren't in the beam.
I don't see why this would be a problem. They can just make use of the irradiation. For example, they could shine the irradiation beam around Chernobyl and sop up all the radiation with the irradiation.

Re:Irradiation, perfect! (0, Troll)

Valdrax (32670) | more than 6 years ago | (#23204928)

I hope you realize that "irradiation" is a real word and that the parent poster was using it correctly. Please tell me you knew that.

Re:Irradiation, perfect! (0)

Anonymous Coward | more than 6 years ago | (#23205038)

It's unpossible he doesn't know it.

Re:Irradiation, perfect! (1)

Hadlock (143607) | more than 6 years ago | (#23205482)

Oh sure, it's like making use of inflammable liquids. For example, you could just inflammable liquid around a burning house and put out all the flames with the inflammable liquid.
 
Dons flame suit
 
+9, ingenious

Never mind the power thing (3, Funny)

jd (1658) | more than 5 years ago | (#23204136)

If the limits on a CD are because of conventional lenses, and this can get 10 times the best a lens can do, it follows that a superlens-based CD, DVD or Blu-Ray system could get 10 times the capacity per track and 10 times as many tracks (in other words, 100 times the capacity). That would be some serious storage space.

Re:Never mind the power thing (2, Interesting)

MichaelSmith (789609) | more than 6 years ago | (#23204236)

a superlens-based CD, DVD or Blu-Ray system could get 10 times the capacity per track
Maybe it could it improve resolution in integrated circuit manufacture as well.

Re:Never mind the power thing (2, Informative)

NeverVotedBush (1041088) | more than 6 years ago | (#23204682)

Circuit fabrication is already using x-rays for the really fine feature devices. The lens they made was for microwaves - much much longer (orders of magnitude longer) wavelengths, where the feature size is possible to construct the capacitors.

The feature size to be able to lens visible light will be much much smaller, and to lens x-rays, will be smaller still.

Since they are using photolithography to create these devices now, they are using a much shorter wavlength of light to make features that allow the lens to work with much longer wavelengths.

To be able to create features small enough to lens x-rays, they will need techniques that don't even exist now.

There could always be some other innovation that this new technique enables, though. Maybe it could eventually happen.

Re:Never mind the power thing (2, Funny)

dgatwood (11270) | more than 6 years ago | (#23204302)

And in 10 years when the price of the media drops to the point of affordability, 5 terabytes will still be too small to back up your hard drive without using a hundred of them.... :-)

Wireless power? (0)

Anonymous Coward | more than 5 years ago | (#23204202)

Cue jokes about batteries in 3...2...1...

Re:Wireless power? (1)

NeverVotedBush (1041088) | more than 6 years ago | (#23204564)

In Soviet Russia, I, for one, welcome our batteryless, microwave-beaming, imagine a beowulf cluster of them, overlords?

Re:Wireless power? (1)

genericpoweruser (1223032) | more than 6 years ago | (#23205196)

Uhm no. You must be new here.

That's great, (0, Redundant)

desierto (568467) | more than 6 years ago | (#23204216)

but where will I put the meter? J.P.M.

Slight Problem? (2, Funny)

Plekto (1018050) | more than 6 years ago | (#23204266)

Current proposed methods for space-based power transmission mean you need a several mile wide area to collect the energy. OTOH, it would be fairly safe. Like a day at the beach. You might get a sunburn but not much else unless you lived right in the path of the beam. And any hard surface, glass, or sunblock would negate almost all of it. But you need a really large area.

The downside of this, obviously, is that if the beam is made twenty times smaller, you would only need a half mile array of collectors, but anything caught underneath it would be fried in a few minutes. (do the math - 20x smaller is several orders of magnitude more powerful - like using a magnifying glass pointed at the sun at half an inch diameter versus a small dot)

Let's hope the aim never gets off.

It's Okay... (0)

Anonymous Coward | more than 6 years ago | (#23204626)

just network [slashdot.org] the computers that control it!

Re:Slight Problem? (1)

Bobb9000 (796960) | more than 6 years ago | (#23204914)

Just because the article says "microwave" doesn't mean they'd use the same frequency as a microwave oven. There are many frequency ranges within the microwave spectrum that don't interact strongly with water. Even setting aside safety concerns, it would be idiotic to use a frequency that couples with water because if you did, every passing cloud would absorb a lot of your energy.

Must...not...power...transfer (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#23204282)

power transfer go boom [memory-alpha.org]

Nothing new here; still not a good idea (3, Insightful)

Whuffo (1043790) | more than 6 years ago | (#23204336)

Beaming power via microwaves has been suggested many times over the years - and it's still not a good idea.

Firstly, it's horribly inefficient. There are significant losses over the signal path that hand waving won't make go away. And then there's the real show-stopper: high power microwave beams would be a hazard to aviation, shipping, or anything or anyone else who got in the way.

There'd be enough scattering of the beam to spread the danger around. Sure, this technology is possible - but there just don't seem to be any practical applications for it. Wire is much more efficient and airmen have a chance to see and avoid it. They'd never know that microwave beam was there until they entered it.

Beaming power in from space is a perennial favorite - but nobody ever seems to be able to get around the atmospheric effects. And I'd prefer to not have any randomly scattered ionizing radiation impinging on my home, thanks.

Re:Nothing new here; still not a good idea (1)

sticks_us (150624) | more than 6 years ago | (#23204476)

These are good points--I'm sure there are people who have weaponized this kind of thing based on the hazards you describe.

I've been fascinated with this topic ever since my "Gamma World" days, where broadcast power was used to provide energy to remote robots, computers, machine-gun emplacements, etc.

And, as for effeciency, I always thought a directed form of energy would avoid the incredible waste you'd find with a pure broadcast-type of power (which would probably decrease in strength proportional to the cube of the distance away from the source).

Re:Nothing new here; still not a good idea (1)

NeverVotedBush (1041088) | more than 6 years ago | (#23204604)

It might be more like the standard inverse square law...

Re:Nothing new here; still not a good idea (1)

sticks_us (150624) | more than 6 years ago | (#23204620)

It might be more like the standard inverse square law...

Yeah, you're probably right. Maybe that's why I don't play Gamma World anymore ;)

Re:Nothing new here; still not a good idea (0)

Anonymous Coward | more than 6 years ago | (#23204508)

spot-on, our school library has "future-tech" books from the 80s advocating the same thing.

Re:Nothing new here; still not a good idea (0)

Anonymous Coward | more than 6 years ago | (#23204616)

Anybody who thinks that microwaves are ionizing radiation is not qualified to comment on this subject.

Re:Nothing new here; still not a good idea (0)

Anonymous Coward | more than 6 years ago | (#23205018)

Anybody who doesn't know the difference between the near field and the far field deserves a red hot poker shoved in that dicksucker below his nose.

Re:Nothing new here; still not a good idea (1)

Jeremi (14640) | more than 6 years ago | (#23204678)

Wire is much more efficient and airmen have a chance to see and avoid it.


It seems to me that airmen see a line of tall towers with blinky red lights at the top, they should know not to fly between the towers whether they see wires between them or not. Even without the possibility of microwave death beams (tm), the wires might just be too small for them to see. Surely they teach this sort of thing in flight school?


That said, I wonder exactly what the consequences would be for an airplane that flew through a tightly focused microwave power beam? Sliced in half?

Re:Nothing new here; still not a good idea (1)

Verteiron (224042) | more than 6 years ago | (#23204734)

The microwaves would induce powerful currents in all the metal in and on the plane. I would say the result would be unpredictable but decidedly non-optimal for anyone on board.

Re:Nothing new here; still not a good idea (1)

NeverVotedBush (1041088) | more than 6 years ago | (#23204780)

"And I'd prefer to not have any randomly scattered ionizing radiation impinging on my home, thanks."

You already do. It's all around you, at varying levels depending on where you live, the altitude where you live, the things in your home, what it's made of, what you eat, etc.

"Cosmic rays" are everywhere and then you have radioactive decay of radon gas, the significant radioactive isotope of potassium (lite salt is slightly radioactive), thorium in lantern mantles, thorium in arc welding rods, traces of uranium and other radioactive materials in everything from granite to concrete, etc.

If you can get your hands on a Geiger counter, it's kind of fun just to roam around and see what gives off easily measurable levels of radioactivity / ionizing radiation. But just be aware that stuff like alpha particles don't register on a number of detector types so if anything, you might be measuring a bit low.

Don't blame the airmen.. (1)

rufusdufus (450462) | more than 6 years ago | (#23204790)

airmen have a chance to see and avoid it
This is not a problem. Pilots already have many many hazards they can't see already. These are marked on the charts as no-go zones.

In reality, most flights are done essentially 'blind' using IFR flight rules that require zero visibility. So this issue is a non-problem.

Re:Nothing new here; still not a good idea (1, Funny)

Anonymous Coward | more than 6 years ago | (#23204996)

Firstly, it's horribly inefficient



Goodness knows we have to be careful about wasting sunlight. It should be conserved; I mean, that's what daylight savings time is about right?

Re:Nothing new here; still not a good idea (1, Interesting)

Anonymous Coward | more than 6 years ago | (#23205162)

I'd prefer to not have any randomly scattered ionizing radiation impinging on my home, thanks.
Well it's a good thing microwave radiation isn't ionizing, then. This obvious mistake makes me less likely to believe every other part of your post. Do you have any actual data about the efficiency of beaming power through the atmosphere and whether it is so bad that it outweighs the advantages of 24/7 sun with no atmospheric attenuation in space, or are you just shooting your mouth off about your completely unfounded opinions?

Re:Nothing new here; still not a good idea (3, Informative)

khallow (566160) | more than 6 years ago | (#23205218)

What I hear is that you can get 85% efficiency on a pass through Earth's atmosphere (between ground and orbit) (which is about equivalent to maybe 8-10 km of sea level atmosphere). That's pretty good and it improves as you increase in altitude. At 18,000 feet (or a bit over 5000 meters) the inefficiency is halved (to I suppose 92-93%). And I'm dubious about your claim that wire is more efficient. Sure running a microwave along the ground is crazy. But bouncing it off an orbital reflector is pretty efficient (or starting with a solar powered satellite in the first place).

Re:Nothing new here; still not a good idea (3, Funny)

bendodge (998616) | more than 6 years ago | (#23205372)

But really! It's been done!
Wireless Extension Cords [thinkgeek.com]

Did we learn nothing from Sim City 2000? (1)

airencracken (993443) | more than 6 years ago | (#23204424)

I mean those microwave power plants have misfires all the time. Can we really afford to lose that arcology? It cost a ton.

Re:Did we learn nothing from Sim City 2000? (1)

smartaleq (905491) | more than 6 years ago | (#23204460)

tagged simcity2000

Tags (1)

dreamchaser (49529) | more than 6 years ago | (#23204486)

I've often bitched about the over use of the whatcouldpossiblygowrong tag, but if ever there was a time for it, this is it.

Re:Tags (1)

DragonTHC (208439) | more than 6 years ago | (#23204608)

fully agreed. people are going to walk around with microscopic holes burned into their bodies and wonder why. This is the dumbest idea ever.

what's wrong with induction for wireless power?

Re:Tags (1)

dreamchaser (49529) | more than 6 years ago | (#23204632)

What's wrong with wires and batteries and compact power plants or fuel cells? Sure, induction could be used for small load short range stuff.

I'm still laughing at the image of holes in people's bodies. I certainly didn't miss the humor.

Re:Tags (1)

NeverVotedBush (1041088) | more than 6 years ago | (#23204820)

Induction works great when you are tightly coupled. But induction occurs through an electromagnetic field and the strength falls off with the square of the distance and you just can't transfer that much energy. It gets really lossy.

It's why power transformers have some kind of core - to help increase the coupling between primary and secondary.

Use in photolithography for VLSI. (1)

bezenek (958723) | more than 6 years ago | (#23204590)

The ability to focus light is currently a limiting factor for reducing the feature size on VLSI chips below 0.45nm. Has this lens been discussed for this use? Thank you in advance for any pointers to write-ups or other information.

And a Miss fire can start a fire takeing the power (1)

Joe The Dragon (967727) | more than 6 years ago | (#23204674)

And a Miss fire can start a fire taking the power plant with it. Pay for the for safer fusion power plant.

Re:And a Miss fire can start a fire takeing the po (0)

Anonymous Coward | more than 6 years ago | (#23204866)

Down with nukes! Nuclear Free Zone!

Moore's Law Application! (1)

Technician (215283) | more than 6 years ago | (#23204688)

Much of the limitation on the speed and size of the newer generation of chips is related to the wavelength of light in the lithography process. The race is to use shorter and shorter wavelengths to make smaller and smaller transistors. If you can put this energy into a space 20 times smaller than the wavelength, then Moore's law lives on. Wow, think of the next generation of lithography and chip manufacturing. Anybody converted the tech from microwave to short wavelength light yet? If not, get busy. There is a patent for the first to demonstrate it in lithography.

Re:Moore's Law Application! (1)

NeverVotedBush (1041088) | more than 6 years ago | (#23204860)

There is another limit to Moore's law - as the feature size has shrunk to literally where you can count the atoms in a trace width, diffusion can cause real problems.

The circuit features literally blur over time and cause failure.

Another issue is leakage currents. As features get smaller, probabilities that electrons can jump around go up. You also have to lower the voltages used on chip because as things get smaller, the voltage gradients go up. Get them too high and you can literally have arcing inside the chip and device failure. As you lower voltages, the way charge gets herded becomes less efficient and leakage currents also go up.

Moore's law really is running out of steam...

Prior Art? (1)

xA40D (180522) | more than 6 years ago | (#23204696)

Okay I claim prior art on "Wireless Wire";

Been banging on about it for years;

But it's Heinlen who really gets the award;

Waldo and Magic inc.;

Me? I've got a problem with Dark Matter.

This unit cannot kill (1)

Dachannien (617929) | more than 6 years ago | (#23204710)

I'm reminded of the Star Trek episode where they power the M5 supercomputer with a high-intensity wireless power transfer beam at roughly shin level.

It's been done. (1)

gpinzone (531794) | more than 6 years ago | (#23204752)

It was called the Broadcast Energy Transmitter or B.E.T. COBRA-LA-LA-LA-LA-LA-LA-LA-LA-LA-LA-LA!

tesla (1)

Clay Pigeon -TPF-VS- (624050) | more than 6 years ago | (#23204848)

Why do I keep having visions of tesla dancing through my head?

So wait (1)

gcnaddict (841664) | more than 6 years ago | (#23204882)

So wait a second... instead of needing a dish that's 1km in diameter, we'll need a dish that's just 1.5cm in diameter?

yeah I know the SC2k jokes are old. I tried.

Catching up with me? (2, Informative)

slack-fu (940017) | more than 6 years ago | (#23204890)

I've had wireless wireless extension cords for YEARS. I can't believe you guys think this is new, here's the site i got mine from. BTW they work great! Wireless extension cords [thinkgeek.com]

This article has a blatantly false statement (1)

JoeBuck (7947) | more than 6 years ago | (#23205364)

It claims:

"No matter how powerful a conventional lens, it cannot focus light down to more than about half its wavelength, the 'diffraction limit'. This limits the amount of data that can be stored on a CD, and the size of features on computer chips."

Wrong. Modern processors are typically produced on a fab that uses 193 nanometer wavelength extreme ultraviolet light, yet cutting edge chips are using 45 nm feature sizes, about 1/4 the wavelength. According to the article this should be impossible.

The way it's done is with masks that compensate for the diffraction pattern, using techniques such as optical proximity correction and phase shift masking. The techniques have limitations, and this results in large numbers of design rules that have to be satisfied to have the process work.

So, why don't they use a smaller wavelength? The answer is because lenses no longer work as you start getting into the X-ray region.

I suspect that these people have inadvertently re-invented a form of phase shift masking. Too bad for them that it's already heavily patented.

Two Words (0)

Anonymous Coward | more than 6 years ago | (#23205410)

Liquid Karma

North American Energy Policy Anyone? (1)

TheNarrator (200498) | more than 6 years ago | (#23205416)

This tech will most likely be developed? Why? I mean there are 100s of other energy ideas blowing around out there.. Why would this one come to be the first significant major power source since nuclear power?

Please Google "North American Energy Policy" sometime.
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