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Power

Solar Power Becoming More Affordable 355

prostoalex writes "With both startups and large companies such as Boeing working on solar power, the technology is becoming more affordable, MIT Technology Review says. Solar power concentrators are all in rage now: 'The thinking behind concentrated solar power is simple. Because energy from the sun, although abundant, is diffuse, generating one gigawatt of power (the size of a typical utility-scale plant) using traditional photovoltaics requires a four-square-mile area of silicon, says Jerry Olson, a research scientist at the National Renewable Energy Laboratory, in Golden, CO. A concentrator system, he says, would replace most of the silicon with plastic or glass lenses or metal reflectors, requiring only as much semiconductor material as it would take to cover an area the size of a typical backyard. And because decreasing the amount of semiconductor needed makes it affordable to use much more efficient types of solar cells, the total footprint of the plant, including the reflectors or lenses, would be only two to two-and-a-half square miles.'"
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Solar Power Becoming More Affordable

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  • by Nom du Keyboard ( 633989 ) on Friday November 10, 2006 @12:45PM (#16794872)
    Solar Power Becoming More Affordable

    This headline can be recycled and reused into perpetuity. Chances are with continuing advancements it will always become more affordable than it was last week, month, year, decade, or century.

    But when will it become truly affordable for the masses? That's what most of us want to know. Wake me when it's time to disconnect from the petroleum/nuclear fired grid.

  • Nitpick (Score:5, Insightful)

    by Rob T Firefly ( 844560 ) on Friday November 10, 2006 @01:08PM (#16795244) Homepage Journal
    Solar Power Becoming More Affordable
    Solar power has always been free. It's the gadgetry that can convert it to certain other kinds of power for us that are getting more affordable. </pedanticbastard>
  • by Vellmont ( 569020 ) on Friday November 10, 2006 @01:19PM (#16795380) Homepage

    Let's just say that it costs a super cheap 20$ a square foot. The cost of the mirrors alone would be $1,115,136,000.


    Wow. I can make up numbers too. Let's assume it was a "super cheap" $2 a square foot. That's only
    $115 million. Oh wait, let's assume it's only .20 a square foot, that's only 11.5 million dollars.

    Rather than pulling numbers out of your ass, maybe you should have real estimates of what it costs to make a plastic mirror. Considering you can make wood flooring for .68 a square foot, I'd say $20 a square foot for some plastic mirror material is totally ridiculous. Beyond that I have no idea how much it'd cost, but I don't think anyone would be talking about this seriously if it cost a billion dollars to just create the mirrors.
  • Re:thermovoltaics (Score:3, Insightful)

    by b0s0z0ku ( 752509 ) on Friday November 10, 2006 @01:22PM (#16795424)
    That way we could apply them to things like brake shoes on cars, the condensers on refrigerators and air conditioners, etc...

    Your idea about the computers and brake shoes would work -- in theory. However, with car and train braking, there's a better way to extract energy from braking - just use an electric motor running as a generator to slow the car. It's done in hybrid cars and the NYC subway.

    As far as the condensers in fridges and A/C units, it won't work, since you'll need more energy to run the thing. TiNSTaaFL. (There is No Such Thing as a Free Lunch.) Nor is there such a thing as perpetuum mobile.

    -b.

  • by Jerf ( 17166 ) on Friday November 10, 2006 @01:24PM (#16795484) Journal
    I truly believe that the #1 reason why distributed power systems like solar, hydrogen, etc, are not taking off are because the big energy companies don't WANT decentralized energy systems - because they can't control the profits as easily.
    Why hypothesize a gigantic multi-company conspiracy, apparently even extending into all the companies doing solar research (who evidently don't want to succeed), when It's been too expensive to be practical seems to cover the bases nicely?

    The problem with all these "The Big Bad Industry doesn't want X to succeed!" is the absolutely staggering number of X's that have nonetheless succeeded. Who cares what my power company "wants"? If I could buy cost-effective solar, I would. I can't. (And given that I live in cloudy Michigan it's going to be even longer for me than for some of you, but that's just a detail.)

    Good luck to any power company foolish enough to stand in the way of something with the PR power of solar power. Can you imagine the media bloodbath that would ensue if any power company executive even mumbled something about getting solar outlawed?

    Seriously, less emotion, more brain. It's the Universe making solar power hard, not a conspiracy of apparently-omnipotent "evil executives".
  • by necro81 ( 917438 ) on Friday November 10, 2006 @01:42PM (#16795754) Journal
    I've worked a lot with photovoltaics. They're really cool, but I recognize their limitations for utility-scale power generation. The primary limitation is that silicon-based photovoltaics currently convert only 10-23% or so of the incident solar power into useful electricity. Silicon solar cells cannot convert infrared light to electricity - the photons have too little energy. Higher energy photons (visible and UV light) are poorly utilized - a solar cell will get the same energy output from a red photon as a blue one, despite the fact that the blue photon has higher energy. Solar cells aren't very reflective (by design), so most of the remainder of the unconverted sunlight becomes heat in the cell.

    You can get higher efficiencies by going to other chemistries, like GaAs, and by layering different chemistries on top of one another. These are not cost effective, and won't ever be able to get above, say, 50% efficiency.

    But solar energy is not limited solely to photovoltaics. Probably the best way to use solar energy is solar thermal - capture all that 1000 W/m^2 of incident sunlight as heat. It can be used to heat a fluid up to fantastic temperatures, which can drive turbines, etc. This is the principle behind Solar One, Two, and Tres [wikipedia.org] and the Nevada Solar One [wikipedia.org] plants. These are, however, demonstration plants, not utility scale.

    The other major kind of solar energy is biomass. Photosynthesis is a pretty good way to capture sunlight and make it do something useful. Plants have had a looong time to get good at making use of sunlight, which we use to our benefit in many ways. When cellulosic ethanol comes around, you'll probably make better use of sunlight by planting crops and building a solar power station.
  • by Dunbal ( 464142 ) on Friday November 10, 2006 @01:44PM (#16795792)
    The cost of the mirrors alone would be $1,115,136,000.

    Ok I'm going to add around another billion to pay for cleaning equipment, staff, etc.

    Let me pull some numbers out of my butt.

    I'm also not a physicist so forgive me if I've made a basic mistake in my following assumption: For your $2B investment you get 1 gigawatt production. What is this - 1 watt = 1 Joule per second, if I remember. So 1 GW = per second. After 3600 seconds you are getting 1GW/hour. Dunno how much a KW/hr costs in your locale, but here it's about $0.12. 1 GW/hr = 1 M Kw/hrs = 1M x $0.12 = $120k worth of energy produced per sunshine hour. Does it pay the interest on the investment? Say you had 2 hours decent sunshine a day on average (because some days it will be cloudy and you won't get 100%) = $240k a day. That's about $87M a year. Hmm, dunno if it's worth it, actually, once you take out operating costs, depreciation, etc. For now. But it could be, someday, if the price of energy goes up much higher. It's not _that_ far off.
  • by dasimms ( 644188 ) on Friday November 10, 2006 @01:54PM (#16795948)
    run off of moonlight
    Wouldn't that also be sun light?
  • Cheaper Mirrors? (Score:2, Insightful)

    by Reidsb ( 944156 ) on Friday November 10, 2006 @02:04PM (#16796068)
    There has to be a HUGE stockpile of old AOL CDs still out there, lets put them to good use.
  • by Dunbal ( 464142 ) on Friday November 10, 2006 @02:13PM (#16796200)
    the desire for lighting when it's dark out.

          Yeah but now that we have clocks and almanacs and things, we know exactly WHEN it will be dark out. The sun rises every day. That's pretty reliable. Not the sun's fault this hulk of a planet gets in the way for half the day.
  • by Lumpy ( 12016 ) on Friday November 10, 2006 @02:30PM (#16796438) Homepage
    First building a proper and efficient home is extremely hard to do.

    1 - they are "ugly" to most people that want the cookie cutter that looks like the other 15 homes in the new subdivision.
    2 - They require more land than the typical suburbian/urban lot offers.
    3 - Actually paying for low-e glass + correct design + insulation is expensive! They would rather have cherry cabinets, stone fireplaces with a plasma TV above it than energy efficiency.
    4 - building from real materials is also insane expensive. I live in a all brick and Stone home now that is from the 1950's It's beautiful and would cost nearly $1,000,000 to build today. The stonework is real the brickwork is real my walls are 2X6 and then have the stonework on the outside giving me 10-12 inch thick walls, new mansions dont have real stone anymore, they have the faux or created stuff that is in reality only an inch or two thick even for their fireplace stonework (I have real marble and limestone) so building the home to have real thermal capabilities is not possible except for the rich.

    5 - efficient materials like adobe is illegal most places, an adobe home is incredibly efficient.
    6 - efficient designs are hard to get approved by the association... Any home that looks different is considered ugly. Domes are the absolutely most efficient. I had one that during some winters was self heating due to the sliders and skylights to the south. Paying $85.00 a year for propane for heat is really stinking nice(1999-2002)

    The common person cant have an efficient home, they cant afford it. Jsut like solar and alternative energy. No average joe can float $5000-8000 for a basic solar install that will pay back in 10 years saving few dollars here and there.
  • by dave1g ( 680091 ) on Friday November 10, 2006 @03:25PM (#16797200) Journal
    Being a frugal college student I hate to run the horrible electric heater that my apartment comes with. So what do I do? I take showers with the ceiling fan on to draw out the steam( heat+humidty feel very good in the dry/cold winter months in Austin Texas...yes i know it doesn tget extremely cold cut we still get below comfortable.) I also shower with the drain plug closed. I dont drain the bathtub until either the next shower or until I have noticed the water has returned to room temp. Thus assuring me that I didnt waste any of the heat used by the electric water heater either.

    This can have the effect of making showers alittle uncomfortable sometimes a cold draft will make it into the shower stall but for the most part it stay really warm in there.

    And of course the normal dress is pants, possibly sweaters or sweat pants to keep warm.
  • by maillemaker ( 924053 ) on Friday November 10, 2006 @04:52PM (#16798452)
    >That's not going to happen. The most plentiful source of hydrogen on the planet is water.
    >No one is going to be able to figure out a system that uses less engerdy to split the molecules
    >than you get in return by burning the hydrogen or using it in fuel cells.

    Man, there are a shit-load of things we buy and use every day that consumed more energy in their making than I get out of it in the end product.

    My reply to this is a big fat "so what"!

    Let's say it takes 100 times as much energy to make a volume of hydrogen than I get when I burn it in my car (I'm pulling this number out of my ass).

    If the hydrogen is cheap, compared to, say, gasoline, who cares how efficient it is?

    OK, so we need a nuclear reactor or giant solar concentrators to crack the water into hydrogen and oxygen. As long as the economies of scale make the end product (they hydrogen) cheap, I don't really care how inefficient the process is to produce it.

    The trick is to find a cost-effective, hopefully renewable way to produce hydrogen. Efficiency is secondary.

  • by greg_barton ( 5551 ) * <greg_barton@yaho ... m minus math_god> on Friday November 10, 2006 @04:57PM (#16798514) Homepage Journal
    The solar electricity is simply profitable.

    Not without tax breaks, it's not

    That's cool.

    So, maybe now that we have a Democratic congress, we can shift those gargantuan tax breaks the oil and gas industries got over to the solar industry?

    They claim a construction cost of less than US$200M, but I would not be at all surprised if they miss their mark significantly.

    Don't we spend about that much per day in Iraq? I think we can spare a bit to remove our reason for being there.
  • by smithmc ( 451373 ) on Friday November 10, 2006 @05:11PM (#16798682) Journal

      Take hydrogen. The day someone figures out how to easily produce hydrogen the days of energy monopolies are over - anyone with access to water (or whatever the raw material turns out to be) can do it.

    Making hydrogen isn't the problem. Storing it, transporting it, and keeping it from leaking out of every valve, seam, and fitting along the way, are the problems.

  • by NerveGas ( 168686 ) on Friday November 10, 2006 @07:22PM (#16800158)
    That doesn't mean that it's useless. More electricity is used during the day, when solar works best.

    Even if we kept the fossil-generators for surge and nighttime, if we managed to produce 35% of our electricity through solar, we'd have cut down our pollution rate considerably. Potentially even more than 35%, because generating 1 kilowatt at a home means that the power plant 20 miles away (or more) can reduce production my significantly more than 1 kilowatt.

    Even with the grid-tie, it isn't an economic joke. It's currently between "somewhat practical" and "not quite practical", and as time goes on, it gets more and more practical every year.

    I'm not one of the people who thinks that we should simply abandon all energy usage, I think that we need to find clean, environmentally sound ways of meeting our energy needs. While solar won't completely fill that need, it goes farther toward making that happen than *almost* anything else out there.

  • by trawg ( 308495 ) on Saturday November 11, 2006 @02:56AM (#16803228) Homepage
    While it is true that areas closer to the equator see more power generation capacity from solar, even areas farther away still benefit from solar's ability to mitigate peak demand in summer and winter.


    I think this is one of the biggest things about solar power that is sadly most often overlooked. Sure, it'd be hell nice to drop all our coal burning plants and replace them with PV panels or thermal Stirling engines or whatever - but noone really expects that to happen overnight.

    But dropping a few panels on rooves would make a massive difference - where I am in Australia we're having issues with power during summer because it's like 35 degrees celcius all day (dropping to like mid 20's if we're lucky at night), so everyone's firing up their air conditioners. Having solar power supplementing the grid during the middle of the day - when airconditioners are fired up the most to help deal with the summer heat - would be pretty awesome and reduce the peak demand.

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