Follow Slashdot blog updates by subscribing to our blog RSS feed

 


Forgot your password?
Close
typodupeerror
×
Science Technology

Solar Power Put to Good Use 254

Posted by Zonk from the better-than-frying-ants dept.
Current Shunts writes "Teams from all over the U.S. and Canada will be competing this summer over a 2,500 mile course from Austin, Texas in the United States to Calgary Alberta Canada for the 2005 North American Solar Challenge. The purpose of this event is to promote renewable energy technologies, integrate science and engineering disciplines, and give competitors an opportunity to showcase their technical and creative abilities." At the same time, zestyalbino writes "Construction on the world's largest solar tower [RMIT] may begin next year in Mildura, Australia. In a nutshell, "An ever present large mass of air under an expansive transparent collector (seven kilometres in diameter) is heated by solar radiation (greenhouse effect) providing a continuous flow of hot air to drive electricity generating turbines located around the base of the one-kilometre tall central tower." There's also an article on Wired."
This discussion has been archived. No new comments can be posted.

Solar Power Put to Good Use More

Solar Power Put to Good Use

Comments Filter:

  • Yes (Score:3, Insightful)

    by pyth ( 87680 ) on Friday February 25, 2005 @09:40PM (#11784539)
    Let's just ignore the chemical costs of making solar collectors.

    • Re:Yes (Score:3, Insightful)

      by nyekulturniy ( 413420 )
      As long as the cost of the energy obtained is higher than the cost of the chemicals, go for it. Besides, the Australian system looks as if it is more reflectors.

      • Re:Yes (Score:2, Interesting)

        by Eccles ( 932 )
        The Australian system is simply a greenhouse that powers turbines, no solar cells at all.

        Given low reserves of oil, relatively remote location, first world technology, and lots of sunshine, Australia seems a country with big incentives and resources to develop solar power.

      • Re:Yes (Score:2, Informative)

        by Farmer Tim ( 530755 )
        "Besides, the Australian system looks as if it is more reflectors."

        If you'd even read the article summary, you'd have noticed that it is in fact a huge greenhouse channelling hot air into a tall funnel with a turbine mounted in it...no reflectors whatsoever, and the ground underneath is still usable.

    • Re:Yes (Score:5, Informative)

      by Anonymous Monkey ( 795756 ) on Friday February 25, 2005 @09:55PM (#11784640)
      "The Solar Tower concept operates on a simple rule of physics - hot air rises" The Solar Tower project uses hot air generated in a big green house to spin a wind turbine. It looks like a cool idea if you ask me. Aneway, the point is, not every form of solar power uses photovoltaic cells. But you do have a point, the chemical cost for photovoltaics right now is very high.

      • That depends (Score:3, Interesting)

        by WindBourne ( 631190 )
        there have been some very cheap processes recently for doing cells. These are cheap, clean to manufactuer, and supposedly have ~30 % efficiency. Right now, they are doing studies to make sure that cell does not break down quickly.

      • Re:Yes (Score:3, Interesting)

        by w42w42 ( 538630 )
        Hot air rises - and it also expands, adding to the effect. It's too bad this type of generator cannot be incorporated into existing structures but on a smaller scale - i.e. office buildings, blacktop streets to heat air, etc.
      • But you do have a point, the chemical cost for photovoltaics right now is very high.I cannot understand how anyone on the net can keep pointing this out - the process to purify silicon for the wafers that make CPUs is the same as that for the silicon solar cells - and other techniques have been developed over the past twenty years that allow us to use multicrystalline silicon and other materials. Industrial processes have a cost, and in the case of the silicon cells that people rant about it is a large ene

    • Re:Yes (Score:2, Insightful)

      by Phanatic1a ( 413374 )
      Oh, it's better than that.

      So far, the main impediment to building the tower has been the cost, with estimates ranging from $500 million to $750 million. Davey won't say how much the project will ultimately cost but said the company is considering two new engineering innovations that will reduce construction costs and improve efficiency.

      Let's assume they don't hit any overruns and go with their minimum estimate of a half billion dollars. That's for 200 megawatts of generation capacity.

      That breaks down

      • Re:Yes (Score:5, Insightful)

        by ErikZ ( 55491 ) on Friday February 25, 2005 @10:14PM (#11784758)
        Yeah, but all you have to do is build a big greenhouse and put a wind turbine in it. Great for countries with low tech and some useless land.

        • I don't know how much of that initial number is real estate - though in some countries it is obviously easier to come by. I also suspect that when one or two of these things are built, their cost would have to come down relative to the power output as risk decreases. I also agree with the original posters point on the relative cost though - the physical generator is gonig to cost the same whether your Kenya or Japan - you still have to buy from the same vendors.

          Where I think this might have interesting p

      • Re:Yes (Score:3, Insightful)

        by ArbitraryConstant ( 763964 )
        While your arugments are true, nothing like this has ever been built before. I think the next biggest solar tower was a little 20 kW thing. This is a prototype. However much it costs, it's safe to assume they will get cheaper in the future.

      • Re:Yes (Score:3, Interesting)

        by grqb ( 410789 )
        These solar towers sound pretty cheap to me. At $2.5-$3.75/watt, they're far cheaper than solar pannels which go for about $8/watt [thewatt.com]. And, nuclear has had subsidies out of the wazoo. Nobody's subsidizing this thing at all (this is mentioned in the Wired article).

      • Re:Yes (Score:2)

        by Rei ( 128717 )
        And I'm sure they'll need a big team of nuclear technicians, fuel produced in a long and expensive refining process, difficult waste disposal regulations, and huge public opposition to deal with.....

        Honestly, for first generation tech, and with what one would expect to be minimal upkeep, this isn't bad. Plus, it acts as a greenhouse to the land beneath it.
      • How much did the comparable (IE: first) nuclear power plant cost per megawatt?

        You can't straight-out compare a mature technology's costs with an experimental prototype's cost.

        • Re:Yes (Score:2, Insightful)

          by SidV ( 800332 )
          "How much did the comparable (IE: first) nuclear power plant cost per megawatt?"

          "That breaks down to 125 acres and $2.5 million dollars per megawatt."

          60MW for 72.5 million dollars or about 1.25 million dollars per megawat in 1954-7 in Shippingport PA.
      • Comment removed based on user account deletion

        • Re:Yes (Score:2, Insightful)

          by SidV ( 800332 )
          I don't know. the 1 Billion (with a "B") + square feet of plastic, and the metal framework to support it, might have something to do with it.

      • Good maths... (Score:5, Insightful)

        by Farmer Tim ( 530755 ) on Saturday February 26, 2005 @12:39AM (#11785442) Journal
        ...but you're only looking at the inital costs, not total cost of operation. A nuclear reactor is far more expensive to run and maintain, contains more moving and pressurized parts requiring higher standards of engineering expertise, reactors produce nuclear waste which is expensive to transport and store (and the waste from the tiny, 45 year old research reactor we have in Sydney is politically volatile enough, thank you), and at the end of the working life there's still the problem of decommissioning with the associated clean-up and disposal costs.

        By comparison, this takes a lot of land (but considering Australia is a largely arid continent with a population not much more than 20 million mostly living on the coastal fringe, appropriate land isn't hard to come by), but requires relatively little maintenance, no expensive and hazardous fuel, little to no full-time supervision, and can be repaired by glaziers rather than expensive nuclear technicians; an entire installation could be run by a staff you could count on one hand. It also wouldn't require the same degree of security, which is another saving.

        Oh, and $1,300 per kW = $1.3 million per MW...slightly more than 50% of what this tower is projected to cost (hardly WAY out of line, nice try at slewing the figures though), so with the overall savings in operational and maintenance costs over an average lifespan of (conservatively) 30 years, the solar tower *still* comes out in front.

      • Re:Yes (Score:2, Informative)

        by dbIII ( 701233 )

        could be build in the US for $1300/kilowatt

        Then why aren't they built then? Perhaps the economic figures are as true as the advertising claim of "clean" which defies reality. You don't call any industrial process "clean" unless you are trying to con people. Also, if you think thermal power generation of any kind scales in a linear fashion then you are misinformed - plus it is worth checking whether those numbers include containment, which is a major expense in nuclear power. Anyone who tells you that n

      • Re:Yes (Score:2)

        by SJ ( 13711 )
        This is all well and good but you left out the rest of the comment.

        With the reactor, you still need fuel, and it produces waste. Both of which are radioactive. Then, there is the cost of containing and disposing of that waste.

        If there is one thing that Australia has lots of, it's dry, hot generally useless land. 125 acres is nothing. We only have 20 million people (the population of New York State) on a land mass about the size of the continental USA.

        Even if it does cost 2.5 million per megawatt, it has
      • Does your cost estimate include nuclear waste handling and storage (for the next few million years)? I guess not. Does it account for the cost of nuclear fuel over a period of 40 years? Environmental problems? Nope. Your guesstimate is just about *building* a nuclear reactor, not maintaining it and cleaning up afterwards.

        This solar tower will not pollute [b]ever[/b] and will not leave our children and grandchildren (and so on) dealing with lethal byproducts. I think it's worth paying a little more at first
      • ... but at least the US won't accuse you of getting ready to build nuclear weapons and hence have to invade you. Only very bad people and the very righteous have nuclear weapons and all the righteous god-chosen seats have been taken... ;-)

    • Re:Yes (Score:5, Informative)

      by Squirmy McPhee ( 856939 ) on Friday February 25, 2005 @10:24PM (#11784803)
      Let's just ignore the chemical costs of making solar collectors.

      What chemical costs might those be? For solar cells, they're quite low -- nothing at all like integrated circuits, if that's what you had in mind. Last I looked, the only chemical waste that the larger plants in the US produced in large enough quantities to report to the EPA was a bit of sodium hydroxide. The plants are larger now than they were then, but the only other chemicals that are commonly used in significant quantities are glycol, sometimes hydrofluoric acid, phosphoric acid (or in some plants POCl3), silane, aluminum, silver, and silicone. Solvents are used only in very small quantities.

      Chemical safety specialists generally regard silane as the most problematic chemical in a PV plant, and even then it is more of an occupational safety issue than a pollution or "chemical cost" issue.

      • Ok - it's not solar cells they're using - they're making a big green house [eden-project.co.uk].

        Currently the best way to make big green houses is with an extruded plastic called ETFE [3m.com]. Sheets of ETFE are welded together to form inflatable pillows. The pillows are clamped together with aluminium extrusions.

        Now ETFE and aluminium have extremely high embodied energy (that's the cost of energy used to make the finished material). They are very light materials, which does offset the embodied energy cost somewhat (as you're using l

    • Re:Yes (Score:5, Informative)

      by Rei ( 128717 ) on Friday February 25, 2005 @10:59PM (#11784978) Homepage
      Let's just ignore the chemical costs of making solar collectors

      Which don't approach the cost of the power that they generate unless you factor in the time for return on profit compared to other forms of power.

      Hu and White in 1983 published the results of a study on Solarex panels; energy payback was 6.4 years, with panels that had 12.4% efficiency. This was from 1977 cells. Nowadays, the numbers are generally 1-3 years. Amorphous pay back the fastest - some even under 1 year.

      The rest of the time, they're just generating power. Dollar payback time is usually 4-10 years.
  • Considering I'm alumni at UofC, AND a graduate of their Engineering program, I wish the hosts all the best. I hope they DESTROY everybody else.

    =)
    • And by destroy, do you mean like what happend to the poor UofW student that was driving their solar car last year, just as it veered outta control head on into a minivan killing him? These damned vehicles prove nothing, they're just dangerous...

      • Re:Good luck to U of C (Score:3, Interesting)

        by miratrix ( 601203 ) *
        It was a University of Toronto student who was involved in the unfortunate accident [utoronto.ca].

        Yes, there are some safety concerns with the solar cars, but the biggest safety concern stems from the simple law of physics - conservation of momentum - the solar cars are just not heavy enough. However, the same safety concerns apply also to any motorcycles on the road, or the those Smart cars.

        Solar cars already travel in a convoy consisting of a lead and chase vehicle with amber warning lights. With extensive driver t
  • They've been doing these races for years... what's the point?
    • People perform and achieve so much more if you give them a challenge. These races are the breeding grounds for new technology that can eventually find its way into future cars.

      What I would like to see is an electric Formula 1 type competition, I would bet that it would only be a few years before we would have electric cars with performance and range to match current Formula 1 cars. With developments in electric motors and battery technology that can then flow on into domestic cars, just like disc brakes
    • They get a little better every time. This summer's race will be considerably longer than the usual race. 2500 miles is nothing to snuff at for these vehicles.

      Two big factors in determining the leaders in the race are the reliability of the vehicle, and the driving strategy. That reliability is a factor is pretty obvious, you break down, you loose time. In a race of this length teams should design their cars so that things like changing a tire are not major headaches. Strategy is important because the

  • "put to good use" (Score:5, Funny)

    by mickyflynn ( 842205 ) on Friday February 25, 2005 @09:44PM (#11784565)
    as opposed to all those evil uses for solar power?

  • Save the world... (Score:2, Interesting)

    by mark0 ( 750639 )
    ... one 7km environmental dead zone at a time.
    • "... one 7km environmental dead zone at a time."

      The idea is that this operates like a very large greenhouse...you know, the things they grow plants in?

      Mildura is in the middle of farming country anyway, affected by soil erosion and salination as it is. A large area like this left fallow will actually improve the environment.
      • At temperatures up to 70 C beneath the greenhouse, nothing is going to grow there and soil moisture will be lost rapidly. It may be possible to use this land to extract salts for industrial use, but given the rather low height of the tower any water evaporated is not going to re-condense before being exhausted and thus contribute nothing to the power output. From this I gather that, as a first approximation, energy expended to evaporate water will be lost (water vapor is lighter than air and will contribute

        • Re:Improve the environment? (Score:5, Informative)

          by Farmer Tim ( 530755 ) on Friday February 25, 2005 @11:27PM (#11785141) Journal
          "At temperatures up to 70 C beneath the greenhouse, nothing is going to grow there and soil moisture will be lost rapidly."

          The highest temperatures will be in the center of the array, and closest to the ceiling. The temerature at ground level and around the rim will be lower, thanks to the very convective effect that makes the whole proposition feasible, but by how much will depend on the ceiling height. Remember thermal gradients; it may not be possible to use the entire area, but a good portion of it will never come close to70 C. I have to point out that growing plants under it is actually part of the proposal, it isn't my idea. If you don't think it's possible, tell the people planning it, I'm sure they'll appreciate the advice.

          "It may be possible to use this land to extract salts for industrial use"

          Not really, it's common sodium chloride, and much more readily available in commercially attractive deposits elsewhere; desalination plants along the nearby Murray River, for example.

          "From this I gather that, as a first approximation, energy expended to evaporate water will be lost"

          Two points: (1) Mildura receives little rainfall (irrigation is vital), so surface water isn't as much of an issue as you might think, and (2) this has probably been included in the effciency calculations.

          "I doubt that a large expanse of even more highly salinated land is going to contribute much to the local environment."

          You don't understand the mechanism behind land salination (in .au, at least). Salt is carried to the surface by the water table rising. Anything that causes a lowering of the water table prevents further salination, so accellerated surface evaporation is as good as revegitation. Again, this has all been taken into account.
      • Mildura is in the middle of farming country anyway
        I read it's going furthur west than there - near "little desert" national park - but there are no other large towns between there and the border.
  • The route is South to North over several days. It should be interesting to see how the milage/day changes as the sunlight amount changes due to their location.
  • There seems to be more and more articles of this nature on slashdot these days. Search for "peak oil" and today and you'll get twice as many results as yesterday.

    Are we in a bit of a state of emergency, or is just something to fill in the news until the next war/economic crisis/natural disaster?

    (p.s. I'm not taking any chances. I'm learning the important survival skillz [webeisteddfod.com])
    • Has it occured to you that maybe it's already happened? After all, oil prices rose to substantial new highs last year, about twice what they were only a few years ago. Welcome to the post-oil world, where oil costs twice what it did back in the long-long ago.

      Not quite as dramatic as you thought it would be, is it?
  • The chart on the web site gives a speed of 49 feet p/s, which is too slow to pick someone straight up. I wonder if the speed in the shaft is higher?

    If this thing is built, it'll show up in Hollywood movie real quick.

    • At 49 fps updraft and 70 C (158 F) shaft temperatures, you could have combination sauna sessions and up-and-down parachute rides. Just be careful not to break the glass you come back down on!

  • Good Use (Score:5, Funny)

    by Oscar_Wilde ( 170568 ) on Friday February 25, 2005 @09:52PM (#11784621) Homepage
    Solar Power Put to Good Use

    Excellent! I was getting tired of all the bad uses it is put to.
  • Wasn't someone going to come out with better solar panels, like five times better? Anyone remember that?

    --grendel drago

  • solar car challenge (Score:4, Insightful)

    by Zapraki ( 737378 ) on Friday February 25, 2005 @09:58PM (#11784653)
    "The purpose of this event is to promote renewable energy technologies, integrate science and engineering disciplines, and give competitors an opportunity to showcase their technical and creative abilities."

    What? I thought the purpose of this event was for the various Engg departments at all the competing schools to have a general good time, fostered by healthy rivalry and no doubt a few unspeakable antics along the way! That is why we have these competitions isn't it? I mean, who really cares about solar power? Especially in Calgary, the Fossil Fuel Capital of Canada.

    Hold on, before you mod this post (+5: flamebait) let me continue.

    I'm in the department of Electrical and Computer Engineering at the University of Calgary, and although I'm not actually on the Solar Car Team (yet... they're recruiting like mad), they did steal our study room to use for their club room. So it's almost like I'm a part of it... sort of. In fact, there's a whole bunch of leftover crap from their wooden prototype crowding the hallways here right now.

    But ya, all joking aside, I think it's a really cool challenge and we here at the UofC look forward to competing alongside other great academic institutions. (And having a good time besides! I tell you, if UofC wins this thing, there's gonna be a party in Calgary the likes of which we haven't seen since our precious Flames almost won the Stanley Cup....)

    Ok, now feel free to mod this (+5: flamebait) for shamelessly bringing up the NHL.. or lack thereof (sigh)

    • This got me thinking. Maybe my school was different, but there wasn't any good software development competitions. Maybe universities should host some software competitions. I'm not talking about the kind where they give you 3 hours, and 10 problems, and see if you can solve them. Have a contest where you turn in a finished product at the end of the year. Program whatever you want. Best program wins. Have different prizes for different categories. This is the reason people aren't that good at program
    • Now all we need is for them to stop treating undergrads like scum.
      • but they are :)
        now go clean the beakers, I have to just get this experiment to go right just one time out of a thousand, and I'll be able to base my entire thesis on that one data point.

  • The original patent on solar chimneys (Score:5, Informative)

    by Brad Lucier ( 547713 ) on Friday February 25, 2005 @10:02PM (#11784677)
    My father invented and patented [purdue.edu] this idea; the US patent, granted in 1981, was originally filed in 1975. He never got a dime out of it, and the patents, in Canada, Australia, Israel, and the US, have all expired. I guess he was ahead of his time. More information here [purdue.edu].
    • For some reason they didn't build them back then. I wonder if the patent was part of the reason. Maybe your dad's patent is a wonderful example of why the current intellectual property rights laws don't really help much with innovation.

      Either way, kudos to him! I hope his name gets mentioned lots whenever there is a press release about these machines. Some how i doubt it though.
    • "My father invented and patented this idea;"

      Whoah.. what just came over me? For a moment, I really hated your dad!
    • Just having a patent does not mean riches. And it shouldn't.

      If you invent something and sit on the idea, you don't deserve to make money.

      Personally, I'd like to see a condition on patents that the idea has to be marketed within 5 years or the patent expires.

      Fucking asshats coming up with a good idea then waiting on the world to beat a fucking path. It doesn't happen like that.

      If anyone ever had a truly revolutionaly idea that they had faith in, they'd go batshit crazy trying to get the world to listen

  • Honestly? I'd rather build a Windmill. I'm not sure if I'll ever own a house where the neighbors won't be upset by that though.
  • there was an article in New Scientist about the solar tower months ago. they talked about the possibility of using it as an actual greenhouse too. the main problem was thought to be keeping it clean.

  • Here is a 10MB torrent of an Animation from the acticle.

    SolarTower-Metric-Short.mpg.torrent [simplecache.com]

  • price of solar chimny and solar panels (Score:5, Insightful)

    by grqb ( 410789 ) on Friday February 25, 2005 @10:15PM (#11784768) Homepage Journal
    I'm surpised that the solar chimny is actually cheaper than solar panels [thewatt.com]. Basic calculations show that the solar chimny costs between $2.5-3.75/watt but solar panels cost about $8/watt. I would have expected the solar chimny to be much more expensive, considering that it's going to be twice the height of the tallest structure today (the CN Tower in Toronto).


    One cool thing about the solar chimny though is that apparently it can generate power 24hrs/day, unlike wind that fluctuates. Basically the solar chimny generates electricity from the same type of turbine that a wind turbines use.

    • It can continue to generate electricity at night because heat energy is stored at the bottom, and as the environment cools at night (as it does fairly quickly in cloudless environments like that) the stored heat can allow the cooler air to rise.

    • Repricing at Kwh (Score:3, Interesting)

      by jmichaelg ( 148257 )
      It may be cheaper than solar panels but it's not cheaper than a gas-powered plant. The price of a gas turbine powerplant runs between $500/Kwh to $1000/Kwh. The chiminey's $2.5/watt figure works out to $2500/Kwh, at a minimum, to build the tower and associated infrastructure.

      "But," you say, "the energy is free..."

      But it's not. Just because the incoming energy is free, it's not free to capture and convert it to electricity. There's a maintenance expense to account for. Remember, this tower is huge, the colle

      • Re:Repricing at Kwh (Score:5, Insightful)

        by grqb ( 410789 ) on Friday February 25, 2005 @11:45PM (#11785239) Homepage Journal
        Sure, there are other costs...but everything has other costs. Can you put a price on the fact that coal spits out 100 times the amount of radioactive material into the air than a similar sized nuclear plant? How do you even clean that up? Also, everything in the energy sector is subsidized. No nuclear power station has EVER broken even in North America...but still our energy bills are cheap...why? Because our energy is subsidized. Maybe you don't need a subsidy to build a coal power plant, but your tax dollars sure do go to paying for environmental damages, health damages and other things associated with the coal power plant.

    • I'm surpised that the solar chimny is actually cheaper than solar panels.

      Solar panels don't scale, they have linear costs - thermal solutions can improve with scale. According to trolls nuclear is linear in cost when it suits them, and not when it suits them - but reality should be considered in all cases.

      With panels you buy another one when you need it - but it costs. With thermal solutions it is a big engineering project with big capital costs that requires planning - in the end you get cheap electrici

  • Promote technologies? (Score:4, Insightful)

    by ctr2sprt ( 574731 ) on Friday February 25, 2005 @10:16PM (#11784771)
    I remember when I was younger first hearing about these races and getting excited. It sounded very high-tech and neat, and plus it was a car race - who doesn't like car races? I was, naturally, very disappointed when I learned how slow these things go. My parents explained to me that they couldn't go faster because they didn't have enough energy to do so. At that point I just thought, "Then why are we wasting time on this?"

    So I'm not sure these guys are really promoting anything. I strongly suspect their races are having the exact opposite effect, in fact: convincing people that solar technology is nowhere near ready for prime-time. Instead of showcasing stuff solar tech can do that nothing else can, they're showcasing the stuff it does really, really poorly.

    As an academic project, I think this is great. I'd love to be involved in it and I'm sure I'd learn a lot just from following it closely. But as PR? Not even close.

    • What are you smoking? The current solar cars can go well over 80 miles per hour. It's done through weight reduction and increases in efficiency. I think at those speeds, it is definitely an interesting race.

  • The 2005 World Solar Challange - Sep 25 - Oct 2... (Score:3, Informative)

    by |>>? ( 157144 ) on Friday February 25, 2005 @10:16PM (#11784772) Homepage
    ...runs from Darwin to Adelaide over 3000km in the Australian Outback. http://www.wsc.org.au/

  • Ha! (Score:3, Funny)

    by Anonymous Coward on Friday February 25, 2005 @10:19PM (#11784775)
    Solar Tower my ass.

    Where's the rollercoaster built around it with the bungy jumpers streaming to and fro? Where the Rush Limbaugh Ride where you can ride a vent of hot air to the top while sucking down pain killers? Where's the naked acrobat midget dancers? I mean, this is Austraila. Can't we at least put a huge magnifying glass at the top to fry tourists like ants? No? And where's the fucking beer?

  • These challenges are useless. (Score:4, Insightful)

    by Insanity ( 26758 ) on Friday February 25, 2005 @10:19PM (#11784777)
    Every year we're subjected to media coverage of a number of these solar-powered races, and with each one, it gets less and less interesting.

    It's not a big surprise that you can take thousands of dollars worth of carbon fiber and build an extremely light and impractically fragile vehicle with a design lifespan of a few dozen hours. No real science is being done in these races, just incremental advancements in the application of computational fluid dynamics and power control circuitry. Reduce the drag coefficient by 0.5% over last year's design, cut the weight by two kilograms... it's a complete waste of time.

    This will *NEVER* result in a practical vehicle, for the simple reason that the theoretical maximum power you can get out of solar cells is on the order of 1000W/m^2. These solar races are not baby steps toward a future in which we'll all be driving solar cars, they are just a dicksizing event between university engineering departments.

    Even as such, they're a waste - there are far more impressive things upon which a group of talented young engineers could focus their efforts.
    • ... the theoretical maximum power you can get out of solar cells is on the order of 1000W/m^2.
      Fine. Suppose that you can get 30%, and that car's effective area is 7 square meters. That's 1000 W/m^2 * 7 * .3 = 2100 W = ~3 HP, which is a fair fraction of a car's cruising requirements and would supply many miles-worth of energy requirements if you charged batteries while the car was parked during the day.

    • Re:These challenges are useless. (Score:5, Insightful)

      by alienw ( 585907 ) <alienw@slashdot.gmail@com> on Saturday February 26, 2005 @12:29AM (#11785411)
      It's not very useful as an everyday car. However, it's a fine example of engineering at its best. That's exactly what, mechanical and electrical engineers are trained to do. A Formula 1 car is not practical for everyday driving, either. But it is an example of advanced engineering. I think you do not exactly understand what engineering is all about.

  • ive beem watching the solar tower site for... (Score:3, Interesting)

    by distantbody ( 852269 ) on Friday February 25, 2005 @10:38PM (#11784867) Journal
    many many months now, and i have scanned it thoroughly for construction dates, and its closer to 2~3 years until the design is even finalised, so 1 year sounds pretty optimistic to me. "worlds largest solar tower"? its will also be the worlds first non-prototype solar tower, 1km tall. i'll be travelling down there from Sydney to monitor its progress. -5 Troll modifier, well at least i got my opinion out :P

  • Wouldn't a solar tower mess up the atmosphere? (Score:2, Interesting)

    by Anonymous Coward
    It just doesn't seem like heating up a bunch of air and blasting it out the top of a 1km high tower can be good for the atmosphere...

    Wouldn't this possibly cause some some kind of weather effect?
  • A better site for it would be over Canberra...... thats where most of the hot air is produced - by politicians that wont support innovative technologies.
  • Um, you have to have 25,000 acres to produce 200MW with that thing. You would have to sacrifice the entire SW US to produce enough energy for California alone.

    I'm sure this 25,000 acres has to be relatively flat as well, making the SW US impossible to use as it is spotted with all sorts of mountains, and the bottom of the tube has to be the highest point under that skirt of solar panels to maximize air flow, so in most places you're talking about a tube sitting at least 200 or 300 feet above the ground.

    I
  • Here in the Netherlands, that solar plant would never work (real well).
    However, having a 7 km in diameter plastic shield out somewhere in a flat field, could potentially collect so much rainwater that it would be enough to power miniature generators!
    The water falling down through holes in the shield could drive small generator blades which should yield massive amounts of energy from the ever falling rain! :)
    I think Seattle might be the first licensee for the technology! Not to mention Asian countries!

  • South Texas to North Texas (Score:3, Funny)

    by Citizen of Earth ( 569446 ) on Saturday February 26, 2005 @11:49AM (#11787528)
    from Austin, Texas in the United States to Calgary Alberta Canada

    Hmmm, from South Texas to North Texas. You'll swear they are exactly the same pickup-truck gun racks!

Slashdot Top Deals

Whoever dies with the most toys wins.

Close