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(Solar) Power to the Masses 471

D3 writes "This report on a solar power tower (pdf) looks extremely interesting. Maybe one day we can have international power lines where all the countries with lots of sunshine provide power to the rest of the world? How cool would that be?" The NY Times has a good article on solar power in Japan.
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(Solar) Power to the Masses

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  • Google link / Mirror (Score:4, Informative)

    by mjmalone ( 677326 ) * on Tuesday July 29, 2003 @02:15PM (#6562813) Homepage
    Google link [nytimes.com]

    PDF Mirror [fuckingpimp.com]
    • by EvilTwinSkippy ( 112490 ) <yoda@NosPAM.etoyoc.com> on Tuesday July 29, 2003 @02:24PM (#6562957) Homepage Journal
      Hey, they looks like the solar plant from Sim City!

      So does that mean I can buy one for $40,000?

  • At last.... (Score:2, Funny)

    by mummers ( 253129 )
    ...a use for global warming :-)
    • Re:At last.... (Score:5, Informative)

      by Frymaster ( 171343 ) on Tuesday July 29, 2003 @02:25PM (#6562966) Homepage Journal
      no! you mean ozone depletion:

      global warming: increase in heat-retaining gasses reduce dissipation of energy from the plaent/atmosphere. since the input of energy from the sun remains constant, mean temperatures rise.

      ozone depletion: stratospheric ozone (o3) blocks high-frequency solar radiation on its way to the earth's surface. less o3 means more high-frequency radiation.

      since solar panels (photovoltaics) are more effective with high-frequency radiation, ozone depletion increases their output.

      global warming just sucks

      • Re:At last.... (Score:3, Informative)

        by Anonymous Coward
        > solar panels (photovoltaics) are more effective with high-frequency radiation

        No, as a matter of fact, they are not. When the frequency is higher, the excess energy is wasted
        as heat. Not only is it not used, but it heats the panels and makes them even less effective.
        Work has been going on for some time on panels that can use the full spectrum, or at least a wider
        swath of it.
      • Well, There's always a chance someone on Slashdot doesn't know this, but... Global Warming / Cooling is junk science. The proponents have blocked appropriate measures of earth's temperatures, which involve measuring the ocean's aggregate temperature, and have done so for about a decade now. The measurement would have involved a solitary underwater explosion, and the sound wave would determine the ocean's temperature (although salinity has an effect, it is far from a trivial science). This would be a t
    • Re:At last.... (Score:2, Interesting)

      by slughead ( 592713 )
      global warming will increase crop yields, provide more rain in some fertile but drought-ridden areas, and increase the usefulness of the currently useless solar power?

      And, of course, there's always the fear of global cooling, which would put us into another iceage and take out tons of inland cities not prepared to deal with the barren landscape. Not to mention the fact that europe would be decimated if another ice age happened, they'd have to take over africa again and live amoungst their ancient mistakes
  • Discover Magazine just did a story [discover.com] on something like this. Unfortunately the full story is only available in dead tree format. If you wait until next month the older article will be available. You can probably check it out at your Dentist's office like I did if you feel like getting a filling.

    EnergyInovations [energyinnovations.com] is working on a small version. From the Discover article it discusses how they refined the stirling engine [howstuffworks.com] with the best tradeoffs [energyinnovations.com] of manufacturing costs to effiency. IIRC they are also making this small enough to make it fit on a roof top.

    Geek fact of the day: A stirling engine is an external combustion engine that runs off the pressure created when one side of its engine gets very hot while the other side stays cool. The greater the temperature difference, the greater the pressure, the greater the energy generated.
    • by Anonymous Coward on Tuesday July 29, 2003 @02:27PM (#6562993)
      Another obvious stirling use is as part of your home heating plant.

      British Gas to launch individual CHP boiler for homes [edie.net]

      British Gas has announced that it is developing a household boiler that generates both heat and electricity, which will increase energy efficiency and cut costs for customers, allowing them to sell excess electricity back to the Grid.

      The new combined heat and power (CHP) boilers, developed by MicroGen Energy

      Think about it. You burn gas to stay warm. (if you don't have a heating season....then you don't) Why not burn the gas to do work? You still get your heat. And the work can make electricity.
    • There's much talk of the technology behind this - but how about the cost? How much would it cost to fit an existing house with a solar panel - and how long would it take to recoup that cost in electricity savings? What kind of running costs do these solar panels have?
      • The idea was that they would get the cost efficiency down to $1/watt with 200 watt systems. Ie, if you wanted to be able to run your PC with a 200 watt P/S off solar, you'd need one of their 6'x9' units, and it would only cost you $200.
        The trouble I see with the units described in the Discover article were space efficiency (need a big roof, just to power my computers) and heat danger (oops, just ignited that pigeon that tried to land on my solar power unit, now I've got a flaming pigeon on my shake roof).
      • Try here [energy.gov]. They have all sorts of goodies on their website. Guides to energy efficient housing, appliances, calculators, and links to other resources.
      • by gaijin99 ( 143693 ) on Tuesday July 29, 2003 @03:14PM (#6563621) Journal
        How much would it cost to fit an existing house with a solar panel - and how long would it take to recoup that cost in electricity savings? What kind of running costs do these solar panels have?

        Very good questions, as it happens, I have answers!

        In California it costs around $15-$20K to refit a house with solar panels. Due to recent legislation the power company MUST pay the wholesale price to any of their customers who generate power. It takes around 20 years for the cost of the panels to be recouped.

        Note that these numbers assume that the cost of power stays stable, which is fairly unlikely. If the cost per kilowatthour increases then it will take proprotionately less time for the panels to pay for themselves. A long term investment, but ultimately worthwhile.

        In terms of pure energy costs (neverminding money) it takes a typical solar panel about three years to generate the amount of energy it took to produce. Some panels are made from recycled wafers (typically wafers which were rejected for chip manufacture) these take about 3 months to make the electricity that went into their production.

        • by Once&FutureRocketman ( 148585 ) <otvk4o702@nOsPAM.sneakemail.com> on Tuesday July 29, 2003 @06:29PM (#6565710) Homepage
          Just a couple of notes, from someone who is currently selling solar for a living in California:


          - a "typical" residential system (2.4kW AC peak output) is going to run $9000-12000 after the state rebate
          - there's also a 15% state tax credit
          - the utility buyback of power is called "net metering" and they actually pay the retail price for the power (i.e. they credit you for power you produce at the same rate they charge you for what you use)

          As to one of the original, unaswered questions: if you don't have batteries (and you don't need them if you are grid connected), the only maintenance required is hosing off the panels a couple of times a year. The panels are warranteed for 25 years, and generally good for much longer.

    • by Lumpy ( 12016 ) on Tuesday July 29, 2003 @02:29PM (#6563022) Homepage
      Home power [homepower.com]

      is a better solution...

      I have my cabin on the lake heated and powered without buying heatoil or electricity... and it's in northern michigan.

      you can do it. and you can do it now. you just need to have a desire that outweighs the convience of simply paying a bill.
    • SHEC Labs [shec-labs.com] in Canada is also working on small(er) units, and potentially catalytic hydrogen generation! You can see videos of their prototype in action here. [sheclabs.com]
  • by xNoLaNx ( 653172 ) on Tuesday July 29, 2003 @02:18PM (#6562850)
    then more power to 'em!
  • by dschuetz ( 10924 ) * <david&dasnet,org> on Tuesday July 29, 2003 @02:18PM (#6562860)
    Maybe one day we can have international power lines where all the countries with lots of sunshine provide power to the rest of the world?

    Great idea, but power simply can't be distributed over that great a distance.

    To make up for losses due to resistance in wires, they up the voltage to absurd levels -- decreasing the current level, and, in the process, the voltage drop over a long distance. However, this can only be taken so far, and towers supplying electricity to the rest of the planet is way too far.

    In fact, I'm pretty sure that the continental US is too wide for coast-to-coast power sharing (that is, power generated in, say, New York, can only be "shipped" as far west as Indiana, or so).

    On the other hand, replace today's wires with some kind of high-current, high-temperature superconductor, and you're golden.

    • Time to come up with cheap room-temperature superconducting wire :)
    • The point is to generate power on the spot so you don't have to ship it!
    • In fact, I'm pretty sure that the continental US is too wide for coast-to-coast power sharing (that is, power generated in, say, New York, can only be "shipped" as far west as Indiana, or so).

      In many parts of the world, you could reach twenty countries at that distance.

    • Great idea, but power simply can't be distributed over that great a distance.

      oh no? as far as I can tell, Canada (where I live) sells power to the US quite frequently, and vice-versa, depending on the month, and whose reactors are up/down.

      the whole power grid allows for this type of 'sharing', but it co$t$ to buy it.....
      (mainly because you need it, and we got it , economy.)

    • This is why superconductor technology is so important. The problem is a general lack of high temperature superconductors. We need them for two reasons. One is power transmission, and the other is heat transmission. A high temperature superconductor with sufficient surface area makes the ultimate heat sink. These two purposes make superconductors indispensible and necessary for the next evolutionary step in technology, which demands greater power storage (or generation) and greater power transmission.
    • Hydrogen pipelines are nearly lossless, also hydrogen allows you to timeshift your production and use of electricity.

      Hydrogen fuel cells are being oversold by many people, but this is one thing that they would be great for.
    • by vkg ( 158234 ) on Tuesday July 29, 2003 @03:14PM (#6563612) Homepage
      Small is Profitable [smallisprofitable.org] by Amory Lovins [google.com] of the Rocky Mountain Institute [rmi.org] is about the benefits of generating your electricity using small, modular power systems where you need them. It turns out that grid infrastructure is often well over 50% of the cost of providing power, and that if you simply install systems like microturbines or small-scale combined wind/solar installations (explained below), you can significantly outperform the grid in terms of end-user price and capital requirement.

      That's not a big deal here, where we already have a grid, but it's a huge, huge deal in the third world.

      The combined solar/wind thing works like this. Electricity demands have a thing called a "load shape" - basically demand graphed against time. It turns out that solar energy supplies match the load shape of things like air conditioners pretty well, but when the clouds come out, your solar supply goes to hell.

      However, wind systems work best when there's a sudden change in temperature, causing new low or high pressure areas, so usually cloudy days have ample wind. If you combine local solar and wind systems in a single "local area grid" you get a hybrid system which produces power in almost exactly the same loadshape as your actual demand, reducing expensive overcapacity, and with excellent availability in all weather conditions.

      Renewable energy requires a lot more smarts than "this is a huge factory which produces megawatts a day" - you don't see nearly the full benefit unless you actually take advantages of the full range of renewable solutions, using factors like their modularity, size, loadshape matching, low capital requirements, grid independence and many other subtle factors.

      Small is Profitable [smallisprofitable.org] is a hard read: about 400 pages of really densely argued financial and technical analysis, but it's pretty much the definitive work in the area. If you want to know more, it's the book to get.
  • but then (Score:5, Funny)

    by crow976 ( 244247 ) on Tuesday July 29, 2003 @02:18PM (#6562861)
    ...the US would takeover those sunny countries.
    • Re:but then (Score:4, Funny)

      by DogIsMyCoprocessor ( 642655 ) <dogismycoprocessor.yahoo@com> on Tuesday July 29, 2003 @02:33PM (#6563081) Homepage
      And protesters would have signs that say "It's all about the sun".
    • Not to worry. They are the same countries. The Middle East will still be a prime location for the worlds energy.
    • Re:but then (Score:4, Insightful)

      by Anonymous Coward on Tuesday July 29, 2003 @02:39PM (#6563172)
      I know it was just a joke. But I just wanted to point out that the US has a rather large desert area that rarely sees clouds.
    • Re:but then (Score:4, Insightful)

      by ocelotbob ( 173602 ) <ocelot.ocelotbob@org> on Tuesday July 29, 2003 @03:00PM (#6563437) Homepage
      Sorry. The US already has enough sunny areas that if solar power were to gain widespread feasability, there would be little to no need to import any energy. There are huge parts of Arizona, Utah, New Mexico, etc that would be perfect for solar generation as they're sunny locations pretty much year round, and would be perfect for generatint power.

      So quit your US baaaad sheepspeak and get your head out of your ass, mmmmkay?

      • Re:but then (Score:3, Interesting)

        by bbc22405 ( 576022 )
        First, the grandparent post was obviously humor, and good humor at that. Parent poster needs to acquire a sense of humor.

        Second, when you said "feasible", you meant "profitable". Certainly such a power plant is feasible; it has already been done!

        Third, regarding the profitability, just how many of these solar tower power plants do you think we could be building with the $5,000,000,000 per month that the USA is spending to be in Iraq? Not to mention the $100,000,000,000 that we already spent getting t

  • by w42w42 ( 538630 ) on Tuesday July 29, 2003 @02:19PM (#6562867)
    I don't know the percentages, but if you were to transfer power from say Mexico to Canada under this scenario, your energy losses would be huge.
    • I don't know the percentages, but if you were to transfer power from say Mexico to Canada under this scenario, your energy losses would be huge.

      if one was to transfer energy from Mexico to Canada (and only God knows why we would do this), it would be transfered from the Mexican border, to the American border. The American border would then sell it up the chain. In the end, it would be an American Border state, that would sell to Canada...the idea of the power is that it is the same, but in reality, it
    • Maybe that's why the prices were so high when British Columbia sold power to California 2-3 years ago? News Story [canada.com]

      Sure price fixing and all that (seperate discussion in possible flame war below), but I wonder if this is a factor? BC to California isn't the shortest distance.
  • by EvilTwinSkippy ( 112490 ) <yoda@NosPAM.etoyoc.com> on Tuesday July 29, 2003 @02:19PM (#6562878) Homepage Journal
    It would be nice to use the energy baking my roof rather than expend energy to pump it out.

    • That does sound interesting. Now all I can think abour are solar powered heat pump.

      > Back in my day I had to write games in BASIC, on a 4.7Mhz computer with no hard disk and 128K of RAM. And I was grateful.

      So did I, but for the first year I did it without dos or a tape drive, meaning I couldn't save.
    • See absorption cooling. Sun-> hot water + electricity + heat + cooling.

      This isn't really big in the US right now, but it's big in Japan. For a US practitioner see Solargenix (just one example).
  • by amorico ( 40859 ) on Tuesday July 29, 2003 @02:20PM (#6562879)
    Will the sunshine nations (OSEC) collude to create artificial shortages and drive up prices in the sunless nations. Rolling blackouts, $700 power bills. The best part will be when they say its the fault of the sunless nations for having draconian environmental laws.

    I'm really not this bitter in person.
  • by Gibble ( 514795 ) on Tuesday July 29, 2003 @02:20PM (#6562892) Homepage
    If governemnts subsidized people to install these instead of new shingles, this would severely cut down energy concerns.

    Of course electric companies would complain, but they will still be needed, solar power won't provide enough power.

    hmm...actually then my electric company would just charge more for less so they don't lose profits...damn
    • by HarveyBirdman ( 627248 ) on Tuesday July 29, 2003 @02:37PM (#6563146) Journal
      If governemnts subsidized people to install these instead of new shingles, this would severely cut down energy concerns.

      Why take the money in the form of taxes, pass it through the government mess, and then dole it back out again? Why not just make the solar panels deductible? Then you avoid a wasteful bureaucracy to manage the subsidies. 100% of the cost goes into the panels. As people buy them, competition heats up, and they become affordable to an increasing number of people.

    • -1, didn't read the article. The PDF is talking about a large solar install that uses mirrors to heat molten salt from 230C (!) to 650C (!!), store it in tanks, then as needed use the heat from the molten salt to flash water to steam to power a 'normal' generator. It's not something you could mount to your roof with any ease :-)
  • solar energy. (Score:5, Insightful)

    by garcia ( 6573 ) * on Tuesday July 29, 2003 @02:20PM (#6562893)
    ok so these people have a 17% electricity bill drop (from what to what in Japan?) after buying an 1100 sq. ft. home that has solar panels...

    How much did having the solar panels on the home add to the price of an already expesive home? How much will the 17% save over the life of the home?

    Are electric rates in Japan like they are here? 17% of my last electric bill (mind you, it's the summer and I have the A/C on at least 8 hours a day and a box fan in the bedroom on at least 10 hours a day) is $4.20 (granted my apt. is 720 sq. ft. instead of 1100).
    • Re:solar energy. (Score:2, Informative)

      by shakah ( 78118 )
      The article's a little short on data to answer your question, but using the article:

      When she, her husband and son lived in a Tokyo apartment, the family paid 16,000 yen ($135) a month for electricity. Now, their bill has fallen by half and they receive about 2,000 yen from Tokyo Electric Power in return for the surplus electricity they generate.

      and assuming that the electricity bill in Yoshikawa would resemble that of their old apartment in Tokyo, it looks like they could be saving about $85/month (~$1K

    • Insulated Concrete Forms [bobvila.com] provide significant (~70%) energy savings for homes in extreme climates.

      Plus, they greatly reduce fire risk, termite risk, and wind damage risk.

      Now, if you combine solar with ICF, you end up with a house that would require very little power from the grid.

    • Re:solar energy. (Score:5, Interesting)

      by maynard ( 3337 ) on Tuesday July 29, 2003 @02:41PM (#6563207) Journal
      According to http://www.humboldt1.com/~michael.welch/pvpayback. pdf [humboldt1.com] photovoltaic payback in all energy costs associated with manufacture is anywhere from 3-7 years, depending on photovoltaic type (CIS or SC-SI) and assuming 5 hours/day of direct sunlight. Interesting read. --M
    • by GuyMannDude ( 574364 ) on Tuesday July 29, 2003 @03:37PM (#6563888) Journal

      You're missing the important point here. It's not that solar power is going to save the Japanese a lot of money. They're desperate to ween themselves off nuclear power using any means necessary. After all, if you had to contend with these three [godzilla.co.jp] smashing your reactors on a yearly basis, wouldn't you be damn anxious to do something -- anything -- to stop relying on nuclear power?

      GMD

  • by Jonsey ( 593310 ) on Tuesday July 29, 2003 @02:20PM (#6562896) Journal
    International Power Sharing/Leasing/Selling is all well and good. However, I truely doubt that the large scale implied by the poster would ever happen. All cables are lossy. Pushing power along cables has energy lost, dependent mostly on how far you're pumping the juice. (Also, voltage, current, resistance of the wire, local EMFs, and all sorts of minor things too)

    While it would rock to have clean energy finally adopted... Carting it across long distances still sucks.

    Gimme Wind, Gimme Solar, hell, I'll even take Geothermal, just make it clean, unobtrusive, and if you'd like, I can sell you some good land in my back yard. *me mutters about pretentions NIMBY asses*
  • *snicker* (Score:4, Funny)

    by somethingwicked ( 260651 ) on Tuesday July 29, 2003 @02:21PM (#6562907)
    I'm sorry, I can't help but smirk and snicker when I think about the Japanese and their

    "Solah Powah Towahs!"

    *smile*
  • by thomas.galvin ( 551471 ) <slashdot@@@thomas-galvin...com> on Tuesday July 29, 2003 @02:21PM (#6562916) Homepage
    We don't really need lines carrying solar power from sunny areas to the rest of the world. There are plenty of environment-friendly ways to generate power; solar in the sunny areas, hydro-electric in areas with lots of waterfalls, etc, windmills in the plains...

    Availability of methods isn't slowing down alternative fule sources; people just see no reason to invest the necessary capital to change over, when burning dead dinosaurs is working quite happily.
    • And remember; it's always sunny in space...
    • Availability of methods isn't slowing down alternative fule sources; people just see no reason to invest the necessary capital to change over, when burning dead dinosaurs is working quite happily.

      Which is why I don't really care about "conserving" gasoline. The gasoline-consuming cars I buy from now on will have decent pollution controls in them. The quicker we use up the dead dinosaurs, the quicker the renewable energy and clean energy sources become cost effective to use.

  • by Anonymous Coward
    OK, we'll let Grapple build it, but if any Decepticons ask if they can help, just say NO.
  • by Lumpy ( 12016 ) on Tuesday July 29, 2003 @02:26PM (#6562971) Homepage
    It requires a complete re-think of the utilities infrastructure and removal of idiots that run them.

    If a normal neighborhood had 2 stationary panels on each home's roof pointed south that backfed to the utility power and they did the storage, it could be a reality right now.

    but it's easier to keep that 1929 Coal plant running and those power commisioners that have no fricking clue or care outside their pocket or circle of power than to change to current technology.

    Anyone here can easily reduce their power consumption to 1/10th of what they use now. Couple that with a city wide solar network with some wind plants like in Macinaw city or out west and you can easily have clean power.

    it's changing government, and the wasteful companies (running 1500 horse power pumps from 1955-1957 instead of buying noew high efficency pumps) that will be nearly impossible...

    Changing to non polluting power will be more difficult than getting bill gates to embrace and use linux.
    • get together in an undeveloped area, far outside the limits of the nearest city, and build something like this from the ground up? Not only will we have a working example of a radically different electric power structure, but think of the implications of a whole town populated with /. readers!

      ...

      Umm... wait. Nevermind. Don't think of that.
    • Big house (Score:5, Interesting)

      by Convergence ( 64135 ) on Tuesday July 29, 2003 @02:51PM (#6563332) Homepage Journal
      Solar insolation is about 1kW/m^2.. Well, except for the earths rotation. Assuming a non-tracking system, we have to divide by a factor of pi, so thats 300 W/m^2.. Well, except that the average efficiency of solar cells is under 15%, so thats 45W/m^2. Now, the average home has what? 2 people in it, and the per-capita electrical usage, averaged over the course of a year is 1kW. So, you need 2kW for that home, and only get 45W/m^2. So, you need 50 square meters of solar cell, correctly angled south. And this is the best case.

      Now account for clouds and dirty cells. Unless you clean the cells every few days and pressure wash them biweekly, better increase the square meters of solar cells another 50%. So, thats 60-80 square meters of cell/house..

      Now the next question. Where do you store all the energy you'll use at night? If you don't store it, where does it come from? Fancy burying a few ton flywheel in your backyard? How about aa closet filled with lead and sulpheric acid batteries? If you're going to use hydrogen to store it, better double or triple the square meters of solar cell for those inefficiencies.

      The same problem applies to 'Solar 2'. You need about 1000 of them to equal the average energy of a nuclear power plant. And another 299000 to equal the mean energy used by the US. To replace all energy used in the US requires about a million Solar 2's.

      • Re:Big house (Score:3, Interesting)

        by doinky ( 633328 )
        You store the power in the grid; the power company maintains the gigantic flywheels. Keep in mind that in sunny climates, the power consumption at 5:00 PM is overwhelmingly higher than at midnight (air conditioning); so the power you need to "save" for nighttime is nowhere near as large as you imply.
    • Luckily most home devices are becoming more efficient. Monitors are even lower power than they used to be, inch for inch, and of course costly LCD displays available today use less power, and supposedly OLED displays will be inexpensive and low power. A topic close to the hearts of geeks.

      Hell, even washing machines are now being sold based on being low-power. We're on our way.

      It's true that more homeowners should be thinking about solar and/or wind, but that's more easily said than done in this time whe

    • If a normal neighborhood had 2 stationary panels on each home's roof pointed south that backfed to the utility power and they did the storage, it could be a reality right now.

      That might work in some areas of the country... it certainly won't work worth a damn in any area of the country that experiences hail or severe winds (like, oh say, virtually the entire southeastern US). Hail utterly destroys solar panels, and it'll happen often enough that it'll ruin your cost return on them. High winds tend to caus
    • For utility installation, you need capitalizations of at most $2000/kW (comparable to hydro and nuclear power plant capital investment requirements) - wind is there now, but solar has some distance to go to be usable as a utility power source. Currently solar photovoltaic systems go for about $2.00/PEAK Watt at best; given night time, solar angle, weather effects etc. and costs beyond the PV cells themselves, that translates to a $8000 to $10,000/kW capitalization requirement right now. PV systems have bee
  • Would it be worth the cost covering subequatorial deserts with solar panels and ship the electricity to the rest of the world? Of course we would lose a lot of electricity because of the transport, we would have to replace the broken panels every once in a while, but wouldn't this still be cheaper than all the petrol, natural gas, uranium we are using for our computers and our cars?

    I suppose that we can build solar panels for significantly cheaper if we are going to cover a whole desert with them. Training
  • Retro (Score:5, Insightful)

    by Euphonious Coward ( 189818 ) on Tuesday July 29, 2003 @02:28PM (#6563010)
    These power tower things are disappointingly retro. Thousands of moving parts, big temperature fluctuations, difficult materials handling problems.

    Australia is building big convection towers. They are just a big (big!) greenhouse sloping up in the center, so the hot air runs up what amounts to a chimney there, and drives a big windmill -- really, a bunch of them -- in the chimney. It has only a few moving parts, and is easy to build with mature technology.

    Simple might not help employ physicists, but it's the right way to build.

    • Re:Retro (Score:4, Insightful)

      by re-geeked ( 113937 ) on Tuesday July 29, 2003 @05:39PM (#6565237)
      But, unlike the tower described, the convection tower does not provide the means to store the energy and throttle production up and down at will -- that is what keeps solar off the radar screen of the big utilities.

      As for the simplicity, you're saying that a humongous enclosure and a kilometer-high chimney (I'm sure you build those in your back yard all the time) is somehow simpler than a bunch of swivelling mirrors? And that gearing a fan to handle spikes and drops and still efficiently work as a turbine is easier than just pumping hot sat through a boiler?

      Finally, "retro" means "we've done this before, we know what we're doing."
  • Bad idea. (Score:2, Funny)

    by grub ( 11606 )

    How short our memories are.. When we get all that solar power the machines will start a war. We'll have to destroy the skies and move the survivors underground to Zion.
  • Line Loss (Score:2, Interesting)

    by Omega1045 ( 584264 )
    I am not a EE, but having a power Co-Op as a major client I know there is a significant line loss (power loss) associated with transmitting power over long distances. There are also major financial, political and citizen factors to overcome when building new transmission lines. The technology looks cool. I think getting the power from a to b will be a bigger issue.
  • http://www.eere.energy.gov/csp/csp_tech.html Sandia actually did quite a bit of research on solar power towers. When Bush got into power, alot of the funding was taken away. Israel's Weizmann institute actually has a working power tower that is more advanced than the ones made at Sandia. http://wis-wander.weizmann.ac.il/site/EN/weizman.a sp?pi=420&doc_id=731
  • all i'm asking is for some prudence and a reality check before ecstatically proclaiming "Maybe one day we can have international power lines where all the countries with lots of sunshine provide power to the rest of the world?"

    i think those sunny countries would rather exist than become giant solar panel farm fields for wasteful cloudy northerners

    current power demands versus current solar technology efficiency: wouldn't that necessitate something like covering the whole sahara desert with solar panels?

    nevermind the gargantuan investment in time and money to build the infrastructure to set this up... and wouldn't covering vast areas of the earth in solar panels have it's own environmental down side?

    i mean, don't get me wrong, hydro/ wind/ solar is wonderful, but isn't the power output from these technolgies miniscule compared to burning hydrocarbons, as environmentally unfriendly as that is?

    we need fusion man, pronto. i want my mr. fusion damnit! ;-)

    • by Waffle Iron ( 339739 ) on Tuesday July 29, 2003 @03:09PM (#6563536)
      current power demands versus current solar technology efficiency: wouldn't that necessitate something like covering the whole sahara desert with solar panels?

      Let's assume we want to provide all of the world's energy needs by solar power. If I recall correctly, the world currently uses about 500 exajoules of primary energy per year, or about 16 terawatts. The sun provides about 1000 watts/m^2 at our distance. However, the overall system efficiency would be somewhere around 1% of that (say 20% solar cell efficiency, 75% loss from night/day/latitude geometry , 40% weather loss, 70% storage conversion and transmission loss). That gives 10W/m^2 average output, so we need 1.6 million square kilometers, about the size of Alaska.

      That sounds bad, but it's actually only 0.3% of the earth's surface area. I would guess that the best way to implement that much collector would be to develop plastic based collectors in huge sheets that are floated on the oceans. Convert the energy to hydrogen on site and pipe it to the consuming countries. By eliminating fossil fuel usage, you free up huge sources of raw materials to make all of that plastic.

      You could argue that that much area would screw with the earth's climate by changing reflectivity. However, at least it's not generating a layer of greenhouse insulator. Moreover, current agriculture practices alter the reflectivity of a much larger percentage of the earth's surface.

      (Don't bother replying to suggest outer space collectors. Say they were 30X more efficient than earth-based systems. Nobody's going to launch satellites with a surface area 3% the size of Alaska. We've been trying to put up a space station the size of my back yard for 20 years now, and still haven't finished.)

  • by b-baggins ( 610215 ) on Tuesday July 29, 2003 @02:32PM (#6563061) Journal
    You know, the author of the article would have more crediblity if he quit using phrases like "Berlin Wall of Solar Power" in the article.

    Also buried in the article is the fact that this rig is so freakin' expensive to set up and so uneconomic to run, that only nations with massive subsidy programs are the ones looking at it. They are targeting Spain because they signed Kyoto and so the government (read taxpayer) is willing to underwrite the whole thing.

    So, who wants to take bets on how long before environmentalists scream that we are destroying the planet by planting hundreds of thousands of square miles of mirrors across the Southwestern desert?

    Have they figured in the cost of replacing sandblasted mirrors and the cost of trucking water in to clean the mirrors?
  • the missing concept behind solar power is that it doens't have to be distributed. As it is, power distribution system lose a bulk of their power on the way to your house. This is why solar panels are sucha good idea: the power loss is minimal when traveling from your roof to your AC inverter in the basement.

    The major problem with solar power is that it isn't economical to buy a solar power system: the cost of the solar cells, inverters, and batteries is too much compared to what the power company would cha
  • The problem with regular solar panels is that you only get power while the sun is shining, these new systems actually have a way of storing that energy using a super-heated substance.

    A system like this could really help equatorial regions that get lots of sunshine, and they wouldnt have nasty environmental damage... but places like Canada (ie where I'm writing from) which receive less sunlight in the winter would find it more difficult to implement this system (ie lower returns).

    OR you could just do wa

  • by jhiv ( 163029 )
    I always wondered what that facility out in the middle of Kirkland Air Base was. It's quite visible when flying into Albuquerque. I thought that they were exerimenting with a way to shoot down terrorist planes using sunlight. (Imagine burning up a terrorist's plane over New York by training all the mirrored windows of the skyscrapers on it.)

    Of course, burning up airplanes wouldn't work well at night.
  • by macshune ( 628296 ) on Tuesday July 29, 2003 @02:36PM (#6563135) Journal
    After reading the article, this plan to use sun-tracking mirrors to melt salt sounds a little more complicated than this [nsw.gov.au] Australian plan. Not only that, but the Australian plan scores more points in the coolness department as the project intends to build the world's tallest structure -- a tower 1 kilometer high. BTW, IANAA (I am not an australian)
  • by libertynews ( 304820 ) on Tuesday July 29, 2003 @02:38PM (#6563165) Homepage
    http://www.powersat.com -- solar power arrays in space (no attentuation by atmosphere or weather) beaming power back to Earth using microwaves. SF author Jerry Pournelle (http://www.jerrypournelle.com) has been advocating these for years.

    Brian
  • ....then why can't we? I mean they were robots bent on distruction and they used renewable sources....we're just people that want to watch TV. Shouldn't be that hard.
  • by ctid ( 449118 ) on Tuesday July 29, 2003 @02:40PM (#6563189) Homepage
    Does anyone else think that this is eventually going to end up as an imaginative way of killing James Bond? The villain will incarcerate Bond in the salt-melting room, give him a long, detailed lecture about his plans for world domination, make a sub-Bond witticism and then go away, explaining that Bond has until sunrise to live. Of course Bond will escape (using some sand-powered laser which Q has fortunately given to him) and the fat guy, sans cat we hope, will end up taking a bath in molten sand. Or is it just me who thinks like this?
  • Remember those articles that talked about a space elevator with a long cable extending to outerspace? What about if we put solar panels in space (LOTS OF THEM) on the backside of earth, still in range to pickup light that didn't fall on the earth.
  • One other thing that's going on right now is that a New York based environmentalist group has started the NY Energy Challenge [nyenergychallenge.org]. Basically, they're challenging people to pledge to consume less energy by replacing incandescent bulbs with compact flourescent bulbs, air dry dishes in dishwashers, replacing inefficient appliances with more efficient models, or by installing renewable energy systems in their homes.

    The primary goal is to show that New York doesn't need [closeindianpoint.org] the 2,000Mw of energy that is generated by I
  • by karlandtanya ( 601084 ) on Tuesday July 29, 2003 @02:44PM (#6563239)
    Oh, give me a locus where the gravitons focus
    Where the three-body problem is solved,
    Where the microwaves play down at three degrees K,
    And the cold virus never evolved.
    (chorus)

    We eat algea pie, our vacuum is high,
    Our ball bearings are perfectly round.
    Our horizon is curved, our warheads are MIRVed,
    And a kilogram weighs half a pound.
    (chorus)

    If we run out of space for our burgeoning race
    No more Lebensraum left for the Mensch
    When we're ready to start, we can take Mars apart,
    If we just find a big enough wrench.
    (chorus)

    I'm sick of this place, it's just McDonald's in space,
    And living up here is a bore.
    Tell the shiggies, "Don't cry," they can kiss me goodbye
    'Cause I'm moving next week to L4!
    (chorus)

    CHORUS: Home, home on LaGrange,
    Where the space debris always collects,
    We possess, so it seems, two of Man's greatest dreams:
    Solar power and zero-gee sex.

    --Home on Lagrange (The L5 Song)

    (c) 1978 by William S. Higgins and Barry D. Gehm

  • by capedgirardeau ( 531367 ) on Tuesday July 29, 2003 @02:44PM (#6563249)

    Possibly the best do it yourselfer magazine I have ever read is dedicated to renewable energy and guerrilla solar.

    Home Power Magazine [homepower.com]

  • by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Tuesday July 29, 2003 @03:01PM (#6563453) Homepage Journal
    Batteries degrade. Capacitors eventually degrade, and they cost a lot in any kind of useful form. The best ways I can see are A> a flywheel and B> electrolytic (is that right?) separation of water to get hydrogen and later burn it for power generation. The problem with the first one is, what do you make the flywheel out of, how do you house it so if it breaks it doesn't blow your house up, how do you keep it quiet, how do you put power into it, how do you take power out of it. The problem with the hydrogen plan is, how do you store it, how do you compress it, etc. Also how do you keep the engine quiet, how big does it need to be, etc.

    The problem is not and never has been generating the power, the problem is storing the power. The power companies barely buy power from individuals; It costs several thousand dollars for the required hardware, and even then they pay you much less than you pay them for power.

    So, how do I cheaply, safely, and non-annoyingly store electrical energy (in some form) and how do I get it back to being usable electrical power later? It's trivial to build wind generators using automotive generators, and build solar panels out of broken solar cells, and for that matter to build your own gas generators using alternators. They kick out 12V which is useful on its own, and you can always use inverters to spit out 110VAC or what have you.

    If you get slightly more uppity you can build your own three phase alternators and use them to drive three phase motors, which are commonly used in machine shop equipment.

  • by Mostly Monkey ( 454505 ) on Tuesday July 29, 2003 @03:30PM (#6563806)
    www.homepower.com is a great site That always offer their current magazine as a free PDF download. Most issues will show several complete setups including diagrams, results, and pictures of several different types of setups. Just in the past I've seen solar, hydroelectric, thermal water heating, and recipies for making bio-diesal from waste cooking oil.
  • Screw this (Score:3, Interesting)

    by Lord_Dweomer ( 648696 ) on Tuesday July 29, 2003 @03:32PM (#6563837) Homepage
    Once we can beam power from space to the surface, or just have a really long connecting tube (space elevator?) we just have to set up a MASSIVE solar array and we're all set.

  • A little reality (Score:4, Insightful)

    by Smallpond ( 221300 ) on Tuesday July 29, 2003 @03:34PM (#6563860) Homepage Journal

    Let's see. The article talks about 200 MW plant. At 1kW/m^2 and 17% efficiency this means we need about 300 acres of mirrors. Seems real practical.
  • by jordandeamattson ( 261036 ) <<moc.liamg> <ta> <mdnadroj>> on Tuesday July 29, 2003 @03:57PM (#6564102) Homepage
    Looking at our electrical bills over the last year averaging between $100 and $150 a month, I decided to look into putting in solar panels and here is what I found out.

    For 7K out of pocket (after tax credits, rebates, etc.), I can get a 2KW solar panel system with grid tie installed. This would give me, conservatively, about 496 KW hours a month in production. This would cut my usage by 2/3s. For 12K out of pocket, I can get a 3KW system which would give me about 720 KW hours a month in production and would completely clear my needs.

    With a grid tie system, I run my meter backwards when my production is greater than my demand. This means that any electricity that I generate is credited against my bill at the rate in play (I believe you also get peak pricing withi this setup) at the time I generate it.

    Bottom line, is that for a 12K investment, I can clear an average bill of $150 a month. This means that in a little over 6 1/2 years I have paid off the system. Or you can think of this as giving me an annual return of 12.5% on my initial investment. That is pretty damn good!
  • Too late (Score:3, Insightful)

    by riptalon ( 595997 ) on Tuesday July 29, 2003 @04:23PM (#6564376)

    But of course it is all far too late. If realistic [princeton.edu] predictions [mines.edu] are anything to go by, world oil production will peak in the next decade and then begin to fall at about 2 percent per year soon afterwards. Even if the US started building wind turbines (the most promising renewable energy source) at a rate of 20,000 a year right now, there would still be major problems. As it is, it looks like everyone is going to carry on as usual until the energy shortages begin, at which point there will not be enough spare energy available to undertake a massive renewable energy building program. Given that more than 4 billion of the worlds 6 billion people are only alive because of the energy subsidy of fossil fuels, which allows chemical fertilizers and mechanised agriculture, the resulting resource wars and famines are likely to be very bad.

  • by re-geeked ( 113937 ) on Tuesday July 29, 2003 @05:26PM (#6565126)
    Doesn't anyone get it? Forget what the submitter tossed in, and the sunny-country factor, this tech is potentially the real deal for one reason:

    STORAGE

    That is, the plant they describe makes it possible to generate electricity any time, day or night, rain or shine. The only limit is that you can't run more than 13 hours without sun at one go.

    This means you can throttle it up and down according to need like a real power plant.

    According to their numbers (which aren't explained, but I assume are based on the 4 years they've been running the prototype plant) they can produce at $.05/kWh, which is below the retail price of electricity in the US, and probably much cheaper than in oil-hungry places like Japan. Also, since those costs are largely (wholly local) construction, land, and maintenance, sunny countries with low labor costs and some desert (India, Pakistan, Brazil, Mexico, Egypt, etc.) would realize an even better price.

    Then there are circumstances they don't mention working in their favor, like:

    World oil production is levelling off and may decrease if more easy reserves aren't found.

    Natural gas supplies aren't as plentiful as hoped.

    No one is building power plants at anything like the rate needed to keep up with demand, and

    Nuclear is still politically untouchable.

    Throw it all together, and a new plant that can produce at that price is a steal.

    Now, if they could float the mirrors around an offshore platform, even the land costs would disappear...

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