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Simcity Microwave Power by 2050?
Politburo writes "The Drudge Report supplies this interesting Senate testimony. Dr. David Criswell, director of the University of Houston's Institute for Space Systems Operations, proposes that we develop robots to assist in the construction of a lunar solar array. The power from this array would be beamed to recievers on Earth, either directly or via relay satellites. Dr. Criswell predicts that with this project, "the average American income could increase from today's ~$35,000/y-person to more than $150,000/y-person." He also attempts to put to rest the idea that microwave power is unsafe, saying, "Each power beam can be safely received, for example, in an industrially zoned area." I wonder if he's ever played SimCity 2000" And coming soon, Godzilla from a drop-down menu.
That this wasn't invented in SimCity. It's a real idea the game developers thought might be used one day.
Energy Conversion Devices has developed a 30 Megawatt solar machine the size of a football field. The device produces nine miles of solar cell at a time. The amorphous solar cells are not great in terms of ultimate conversion efficiency, but they are unique in that they will put out much more power over their life time than the energy used to produce them. They are great on a watt per dollar basis.
Life is the leading cause of death in America.
the average American income could increase from today's ~$35,000/y-person to more than $150,000/y-person
It better be a lot more than that. By 2050 inflation alone should push a $35,000/year income to $225,000/year (assuming the inflation rates of the last 47 years stay about the same over the next 47).
Never approach a vast undertaking with a half-vast plan.
For all those that are "too cool" for SimCity... Microwave power was a great way to provide good-level, affordable-cost power to the citizens of your city. An array in space would power your land-bound power-station nicely, but the downside to this was that every so often it would miss the power station (oops) and fry something in your city.
Maybe if they play Simcity for awhile, they'll realize that this invention might work much better if they do, in fact, build such a power plant with a few fire-stations nearby... but I'd imagine a real-world application would have some form of laser-alignment system that has the array blocked until it's properly aligned with the receiving station.
This site also has some interesting information on beamed-power research.
There are even competitions!
"Studies have shown that people who eat peanuts live longer than those who do not eat."
That hasn't been true for a long time now. Photovoltaics repay the engery invested in them in the first few years of their life, and everything after that is gravy.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
Yes it has - that statistic dates from ca. 1974, when solar cells were essentially hand-assembled from purpose-grown silicon crystals. The National Renewable Energy Laboratory did a study on this a few years back, estimating ca. 3 years' energy payback from hugely conservative assumptions - Here, in PDF form. However, current efficiencies are slightly better than they were at the time, and silicon production has improved as well...(check shellsolar for their latest.) Silicon being your major material and energy cost here, in most cases...the rest is just frames, glass, and wires. If, as it appears, Uni-Solar/ECD has finally got their production line unscrewed, they'll ahve even better efficiencies,a s they use a thin-film process.
The main problem would more likely be what if a cold current of air changes the refractivity of some part of the atmosphere just a little bit so that the beam goes just .1 of a degree off and cooks up a residential neighbourhood instead of providing it with electricity...
Lets check the math on this one. Air has an index of refraction of about 1.000292. The .000292 portion is roughly proportional to the density of the air, which is roughly proportional to the absolute temperature of the air. Assuming a 40,000 foot air column and a beam-to-atmosphere incidence angle of 50 degreees (power to a city in the far north or south from an equatorial-orbit power station), the deflection angle due to refraction is about 0.02 degrees or about 14 feet in total.
This 14 foot refraction is also roughly proportional to the absolute temperature of the air. Between summer (35 C) and winter(-35 C), we have a temperature range of about 23%. So the beam will wander about only about 3 feet over the most extreme temperature variations that are likely. (This calculation is only an approximation, but I am sure it is accurate enough to show that refraction is not a big deal.)
Others will have to comment on scattering.
Two wrongs don't make a right, but three lefts do.
Low beam density makes it a useless weapon.
The whole concept is that you could make a system with a beam density low enough that the focusing antenna is reasonably small, yet, with the beam density high enough that its not cheaper to just slap down solar cells on the ground.
Essentially you are getting more power from the cells in space, so as to offset the transmission and "shipping" (rocket launch) costs.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Uh, we bounce lasers from earth to the moon, all day long, every day. They are measuring the distance to the moon, using the speed of light. It doesn't diverge any practical distance at all.
Read here
We are hitting a reflectr 46cm^2 thats A LOT less than a mile deviation. the 46cm is just for things like vibration, and aiming issues.
BTW, this laster tells us the moon is drifting away from the earth, at 3.8cm per year!
After reading the article, it appears the max power of the beam that reaches individual substations is 20% of noon-time sunlight.
I think the FUD slashdot users have built into this system can now safely be ignored.
-Malakai
A Dragon Lives in my Garage
OK, here's my quick off-the-cuff calculations on this:
.6 seconds, as opposed to the approx 2 seconds rtt to luna)
/second. Worst-case, the beam travels the 2km in exactly the 2 seconds of rtt. The hundred meters of beam width will pass over any point along that path in approx .1 seconds, adding 10 watt-hr/sq meter, i.e., 10 watt-hr to our worst-case prostrate person. If I'm doing my calculations correctly, that's about 9000 calories. I occlude about 1 square meter, and mass about 100 kilos. One calorie raises one gram one degree celcius, so that energy would raise my body temperature by .09 degrees celsius, which I doubt I would notice.
.000001 seconds, and then stopped dead for 2 seconds. That would deliver 200 watt-hrs, elevating the temperature of prostrate people in the vicinity by about 1.8 degrees celsius, which would probably be noticable, but unlikely to be deadly (and extremely unlikely to melt the ground to a puddle of glowing magma...) (of course, all of this assumes that the person is absorbing 100% of the transmitted energy.) However, it seems to me that there are reasonably simple ways to make this sort of failure much more difficult (I'm thinking that the relay station is in two components, a transmitter and a colimator, tethered together with the center-of-gravity of the entire structure being in geosync and tidal forces providing tension on the tethers. Put a wave-guide assembly between the transmitter and the colimator so that mis-alignment will turn it from a wave guide into a reflector. That would mean that a drift off-target would require the entire assembly to move, so you've got a lot of inertia guaranteeing that drift will tend to be constant, as opposed to jerking far off target and then stopping suddenly)
assumptions:
the beam is 3.6Gw (which is a fairly large amount...)
collector is 100 M on a side (10,000 sq m)
nearest un-shielded habitation is 2km away
out-of-alignment condition will be noticed immediately, but will take one speed-of-light rtt to shut down (note, if the collector is on the lunar surface, but relay satellites are in geosync, then the rtt from the geosync satellites is about
worst-case scenario is a prostrate person occluding 1 sq. M of space.
calculations:
The beam is delivering 360 Kw/sq m, 100 watt-hrs/sq meter
Now, the *really* worst case scenario would be if the beam traveled the 2Km in
Pound! Bang! Bin! Bash! is this a shell script or a Batman comic?
I didn't say electronic, I said electric, though it will be both electronic (electrically controlled) and electric (electrically driven.)
I refer you to a Ford page on Hydrogen Internal Combustion which was the first link in a google search on "hydrogen supercharger gasoline"; hydrogen and supercharger for obvious reasons, gasoline because we're talking about gasoline engines. Ford is also using high compression pistons, but with the use of an electric supercharger, this should not be necessary, only a good idea. A set of high compression pistons for a 4 cylinder car costs approximately $500 (for forged pistons) plus another $100 in rings, so it's not all that expensive, but investing in the labor is pretty significant. Ford is also using coil on plug, which is also not necessary, but certainly makes the ECU program a lot simpler.
I direct you to the following paragraph:
Ford is using the same engine in which they ordinarily burn gasoline, but with higher compression and different fuel injectors.
As far as an "electronic supercharger" (if I put an electronic boost gauge in my turbo system, that's effectively an electronic supercharger, a meaningless term if I've ever seen one - again, you want the word electric or perhaps the phrase electrically driven) goes, the ones sold on ebay won't even provide 1.5PSI over regular. They can't compress air. They're just fans. However there are real live electric superchargers such as one from Visteon spoken of here.
Note that on some cars, the so-called electric superchargers such as e-Ram may improve power by improving the dispersion of fuel into the fuel-air mix by creating a vortex effect in the intake and thus in the combustion chamber, but they could also worsen it through the same effect, in the case of vehicles with a tuned intake. Most intakes are built for price and not performance, which is why intake porting alone can produce several horsepower, but on those which are designed for power, the e-Ram will likely decrease performance.
Also, the simple installation of an actual supercharger on a car without a MAP, or Mass Air Pressure sensor, will cause the car to run lean, thus likely leading to detonation. Most cars which do not use "speed density" methods for deciding how much air is entering (at such and such speed, so much air) use a MAF or Mass Air Flow sensor which determines airflow based on either the deflection of a reed or the difference in temperature of a hot wire not in the airflow, and one which is. Since denser air will carry away more heat, this system will work to a certain degree for supercharged systems, but in many cases they're not up to the task. I believe some modern Mustangs use pressure sensors.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"