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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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  • Obvious to me... (Score:5, Interesting)

    by Fishbulb ( 32296 ) on Friday November 10, 2006 @12:50PM (#16794946)
    Why all the talk of centralized power generation?

    Solar panels are the way to put power generation into the hands of the people. When I look out at all the rooftops in the area - houses, office buildings, Super S-Marts and their enormous un-covered parking lots, all I can think of is if every one of those surfaces had a single solar panel our energy demands from centralized (corporate :p) energy would a fraction of what it is now.

    Have we learned nothing from decentralized computing?

  • by majutsu ( 1018766 ) on Friday November 10, 2006 @12:50PM (#16794954)
    years. One of the major problems of concentrated solar power is the heat - normal photovoltaics would melt. The benefit is that concentrated light also has better efficiency than the normal ~10-22% of normal solar power. One of the traditional ways around the heat problem wasn't to use a photovoltacic as all. An energy farm in Australia uses dishes to focus the light and at the focal point places a stirling engine, with only the heat powering it. Interesting stuff. I hope to have my own workable solar power system power my property one of these days.
  • by abramsh ( 102178 ) on Friday November 10, 2006 @12:54PM (#16795020) Homepage
    That's an interesting comment because the price you quoted is roughly the cost of building a new 1 gigawatt nuclear power plant. How do you think the costs of nuclear qualified workers, nuclear fuel, insurance, long-term storage of spent fuel all compare with the labor costs of cleaning plastic mirrors once a year?
  • by maillemaker ( 924053 ) on Friday November 10, 2006 @01:00PM (#16795126)
    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.

    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.

    Same with solar. If they got efficient solar panels so you could be energy self-sufficient there are a lot of people in power with a lot of money who no longer would be in control of the show.

    Steve
  • by b0s0z0ku ( 752509 ) on Friday November 10, 2006 @01:04PM (#16795180)
    A lot of oil and other fossil fuel is expended heating homes. With proper design - like areas of south-facing insulated glass combined with materials that store and release heat (thermal mass) you can have a house that's at least partially self-heating in winter. This doesn't require expensive photovoltaic panels or thermal solar systems. This just requires a bit of thought when building or renovating a house. You can even use build the solar area of the house as a small greenhouse and use it to grow vegetables (far healthier than eating chemically-polluted stuff from the grocery IMHO) almost year round.

    What about in summer? The windows can be opened and replaced by screens or shaded.

    -b.

  • by b0s0z0ku ( 752509 ) on Friday November 10, 2006 @01:13PM (#16795304)
    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.

    Then again, they could just reorganize and move into the manufacturing and maintenance side of things. Someone will have to fix and maintain the solar homepower systems ultimately. The one major advantage of having a power distribution grid, though, is the ability to redistribute power. If Sunville, AZ is having a month of sun with no clouds, and it has been cloudy for a month in Bad Ass, MS, the energy can be redistributed so that all of the Badassian's batteries don't run down.

    -b.

  • thermovoltaics (Score:3, Interesting)

    by spankey51 ( 804888 ) on Friday November 10, 2006 @01:14PM (#16795308)
    One thing I really wish would happen is that the efficiency of thermovoltaic technology could somehow be improved... Think about how much energy is wasted as heat; eventually all of it, I suppose. I actually heat my bedroom in the winter with my PC. When I read about large scale solar facilities, I can't help but wonder at the losses in heat that are going on there. There are more efficient ways of utilizing solar power right now anyway: http://www.stirlingenergy.com/ [stirlingenergy.com] comes to mind... and they work pretty well. It would be nice, however, to move the technology to solid state like we have with photovoltaic cells; That way we could apply them to things like brake shoes on cars, the condensers on refrigerators and air conditioners, etc... -Photovoltaic paint has been invented, but is not realistic yet. I think that's where the future is: Objects that need electricity should become more efficient, and should have photo/thermovoltaic technology built right into them.
  • Durability (Score:4, Interesting)

    by Chas ( 5144 ) on Friday November 10, 2006 @01:19PM (#16795372) Homepage Journal
    Part of the problem is the durability of these panels. The affordable ones have relatively short lifespans (under 10 years, and at that point, still haven't saved enough to justify their cost). The ones that ARE durable enough to last longer are hideously expensive, and not the sort of thing most people have the cash for.

    Also, there's the fact that solar power is not a viable solution everywhere in the world. Sure, in Arizona, California, etc, it is a wonderful "free energy" thing.

    In Pacific Northwest, the northern Midwest, etc, especially during the winter months, solar power is a complete non-option.
  • by Martin Blank ( 154261 ) on Friday November 10, 2006 @01:26PM (#16795498) Homepage Journal
    The solar electricity is simply profitable.

    Not without tax breaks, it's not, at least for older tech. The Stirling generators that are intended for the SDG&E project (and which are also planned for a 500MW facility near Victorville) may change that, but we'll have to see how they handle the weather conditions here (as opposed to New Mexico) over the long term. And while the deal may be huge in terms of solar, it's really not that large when put in perspective with other plants, where 500MW-600MW plant construction is not terribly uncommon.

    The solar tower is interesting, but it's been years since they announced it, and they don't even have all of the permits yet. I question the efficiency of land use as well -- 9400 acres for 200MW, compared to 4500 acres for 500MW for the Victor Valley project I mentioned above and between 2500 and 1600 acres for 1000MW for the setup in TFA. They claim a construction cost of less than US$200M, but I would not be at all surprised if they miss their mark significantly.
  • Re:Obvious to me... (Score:2, Interesting)

    by lagunathed ( 1025578 ) on Friday November 10, 2006 @01:35PM (#16795658)
    I ran across some technology where a building can use its windows (with a clear / tinted film) to capture sunlight to generate power. It's not bleeding-edge new, but we may see some advancement fairly soon. Imagine self-sufficient office buildings or houses for that matter. XsunX [xsunx.com] is one of the businesses I have been following.
  • by Skapare ( 16644 ) on Friday November 10, 2006 @01:51PM (#16795890) Homepage

    We still need better inverters. These are the devices that convert DC into AC for use by common appliances and to power your home. The ones designed for home operation are wimpy, apparently intended for a home where people trim back on using energy in electrical form, already. The ones designed specifically for the wide range of voltage change from photovoltaic arrays/strings are big expensive commercial units intended for selling power to utilities, or for the utilities to buy for themselves (they shut down and night and can't run from batteries very well).

    I want to reduce my carbon footprint with emphasis on reducing use of fossil fuels in particular. I'm less concerned about burning wood than I am about burning gas (natural gas or liquified propane). So I'd like to run my kitchen from solar and wind generated electricity. That means I need on the order of 12 kW of power just for potential peak cooking. Add another 2 kW for microwave. Add some more watts for the blender, coffee maker, refrigerator, etc. It adds up.

    One of the big makers of home inverters for general DC conversion (e.g. batteries charged from various sources) is Xantrex. But their largest unit in this market segment is only 5500 watts. Two of the North American 120 volt units can be "stacked" to get 120/240 volts, but that's still only 11 kW. Some other companies offer as much as 6000 watts in a single unit, and do not even appear to be "stackable". What we need is a line of inverters, each specifically designed for the various world power systems so people can use their common domestic appliances, but with a variety of power levels in many steps all the way up to 100 kW or more.

    There is one technical issue with inverters, and this is not something that is easy to solve. It also exists to some extent with small generators. That issue is that under short circuit conditions, they produce only barely (about 15%) more current than their design rating. To many this might seem like a good thing. But it actually is a hazard. The reason is because short circuits will fail to trip home branch circuit breakers. A common circuit breaker rated for say 15 amps generally won't trip for a while under a 20 amp load, until its thermal element gets quite warm. For an instantaneous trip using its magnetic element, the current has to be significantly higher, like 150 amps or more. Utility power through a transformer can easily deliver several hundred amps under a short circuit condition. With hefty power lines and transformers these days, if you are close to the transformer, you could even get several thousand amps real close to the breaker panel. This is why if you have ever shorted out a power circuit, you get a nasty *POP*. That's some big amps followed by the breaker cutting the circuit off.

    I've found some inverters that have circuit breakers on the output AC side that are rated at a higher amperage than the maximum they could deliver under a short circuit condition. In other words, short out the AC right after the circuit breaker and you can't even get enough juice to cause the breaker to kick off. The inverter itself may very well detect the overload and soon shut off.

    Many appliances may not even work under this low fault current condition. Big motors can have trouble getting started if they can't pull 3 to 5 times the normal amperage for part or all of a second. And even some electronics wants that much power or more when you turn them on to charge up the power supply capacitors. One relative has found that his big screen TV, although using way less than the 5000 watts his generator can produce, just won't even turn on under the generator. When he turns it on with utility power, all the lights in the house dim significantly for just an instant as the monster sucks a huge number of amps.

    Ultimately, if you want to power you whole home with AC power through an inverter that converts the DC stored in your batteries charged up from your solar and/or wind power sources, you'll need some hefty

  • by MrMarket ( 983874 ) on Friday November 10, 2006 @02:09PM (#16796142) Journal
    Couldn't power companies get into the business of leasing the roof-top systems? The pricing structure could be based on how much power the customer consumes. The power company could also sell the surplus power through the grid.
  • by Anonymous Coward on Friday November 10, 2006 @02:18PM (#16796294)
    These guys aren't too clever to bring this up during such dark seasons for most of us in the northern hemisphere. Power from the sun isn't really what's on my mind this time of the year.
  • by b0s0z0ku ( 752509 ) on Friday November 10, 2006 @02:46PM (#16796616)
    1 - they are "ugly" to most people that want the cookie cutter that looks like the other 15 homes in the new subdivision.

    Not necessarily. Besides, the suburban houses that are being barfed up by builders there days are cheaply built and ugly. Yay for particleboard (not the good kind!) roof beams. How they get some of that stuff past the inspectors I can only guess.

    2 - They require more land than the typical suburbian/urban lot offers.

    Incorrect. We had a 1200 sq ft beach house on a *tiny* (read: a 15' x 15' patio in back and 6' on either side of the house) lot. It had a glazed front porce and lots of south-facing glass. The temp of the place didn't drop below 55-60F in winter without heat.

    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.

    Unfortunately true. Consumers are mostly retarded. A lot of builders are greedy SOBs that would build out of sawdust and ducttape if they could.

    6 - efficient designs are hard to get approved by the association... Any home that looks different is considered ugly.

    Fortunately, associations don't have power in all places. Some states have even legally curtailed their power pretty severely. Personally, if I own the land, I should be able to build whatever I want on it within the limits of zoning at the time when the land was purchased. Anyone who says otherwise deserves to get thrown into the swamps with a pair of concrete boots and no lifejacket :)

    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.

    Nah, they don't want to afford it. They'd rather pay $40000 for the latest monster truck or whatever the fad of the day is. And they'd also be able to have a more energy efficient home if they were willing to live in a smaller place. Say, 1200 or 1500 sq. ft., not the 3000 sq. ft. cardboard boxes that are going up now. I'm not talking about major changes here, BTW, just efficient use of glass and thermal storage materials (which can very well be concrete covered with a stone or brick facade, BTW).

    -b.

  • by spage ( 73271 ) <`moc.egapreiks' `ta' `egaps'> on Friday November 10, 2006 @03:23PM (#16797166)

    Energy Innovations [energyinnovations.com] has tried Fresnel and is working on mechanically steered 5x5 set of mirrors.

    Your box sounds promising but a grid of them requires an elaborate supporting frame? The Energy Innovations Sunflower 250 [energyinnovations.com] lies flat on the roof. Your water heat collector adds expense.

  • by Shannon Love ( 705240 ) on Friday November 10, 2006 @03:55PM (#16797704) Homepage
    The problem with solar power is never the efficiency of the collection system but rather with the fact that the power cannot used on demand. Without a staggeringly efficient means of storing the power, solar power will remain useless for all serious generation. There isn't a single factory, communication system, transportation system or any other important part of our civilization that runs off solar power and baring currently unforeseen breakthroughs in storage technology there never will be. We simply can't run a modern civilization off a power source that randomly disappears. Every solar power installation requires a 100% non-solar redundant system to take up the slack when the solar goes off line. Factor that cost in and solar power becomes an economic joke.

    Solar power isn't a solution. Its a distraction. It lets politicians and others pretend that they are doing something about serious energy questions instead of making unpopular, real-world choices.

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