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    • CommentAuthorKosmopolit
    • CommentTimeApr 15th 2009
     (2422.21)
    GI, I looked at that article and I'm a little skeptical.

    Satellites in geosynchronous orbit need to orbit around the equator, leaving aside all the other risks, placing the ground antenna in Fresno will mean a big reduction in power received compared with somewhere on or near the equator.
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      CommentAuthorOsmosis
    • CommentTimeApr 18th 2009
     (2422.22)
    $5bn for 200MW capacity is ... kinda pricey.
  1.  (2422.23)
    $5bn for 200MW capacity is ... kinda pricey.

    Yes, but if it can be done it offers a way to create new power stations without the NIMBY issues that make wind, coal, wave, and nuclear such a PITA. More importantly, it also offers a way to send power right down into a large city as opposed to building one of these theoretical twenty-first century electricity grids that politicians and futurists pretend will pop into being an obviate the laws of physics that make transmitting electric current over long distances so inefficient. To countries like China and India this would be a godsend—they provide power and create jobs without having to seize more farms to build polluting coal plants, while justifying space programs that are increasingly unpopular with the restless and disenfranchised lower classes. If the costs can be brought down to a profitable level over time the businesses building and maintaining them stand to make even more money than the companies doing nuke plants now.
    • CommentAuthorKosmopolit
    • CommentTimeApr 18th 2009 edited
     (2422.24)
    @Osmosis - it's a prototype. And running costs should be low.

    Although you have to wonder what allowance has been made for ground gear maintenance and for in-space repairs and maintenance.
    • CommentAuthorKosmopolit
    • CommentTimeApr 18th 2009 edited
     (2422.25)
    "...these theoretical twenty-first century electricity grids that politicians and futurists pretend will pop into being an obviate the laws of physics that make transmitting electric current over long distances so inefficient...."

    No, the laws of physics say that long distance transmission of high voltage DC is far more efficient than AC and we have real world examples of 1,000-mile plus HVDC lines to back that up.
    • CommentAuthorKosmopolit
    • CommentTimeApr 18th 2009
     (2422.26)
    HVDC is a mature technology.

    For example:

    Swiss power and automation technology group ABB said that it has won an order worth around $140 million to deliver transformers to the State Grid Corporation of China for a high-voltage power corridor that will strengthen the Chinese electricity network and help meet rising demand in the Shandong coastal region.

    According to the company, the power link will transmit 4,000MW of electricity at 660kV over 1,350km, from the Ningxia province to Shandong. The corridor will use high-voltage direct current (HVDC) technology to maximize transmission efficiency.


    link
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      CommentAuthorOsmosis
    • CommentTimeApr 19th 2009
     (2422.27)
    I understand that prototype != commercial version, and that every technology must begin somewhere. I certainly see the benefits that James points out, and don't get me wrong, I'll be cheering Solaren et al if they can make this work. My main problem with the concept is that I wonder, with orbital lift costing what it does, whether this will ever be cost-effective versus ground-based tech we have now.
    • CommentAuthorKosmopolit
    • CommentTimeJun 25th 2009
     (2422.28)
    Interesting take on the problem:

    1. A modular system with multiple satellites transmitting power to a single transmitter which then beams it to Earth - makes the whole thing more viable because you can build it in stages and use existing rockets to put up all or msot of the components.

    2. In the first instance, rather than beaming the power ti Earth beam it to satellites in LEO with ion engines to propel them to GEO.

    link
    • CommentAuthor256
    • CommentTimeJun 26th 2009
     (2422.29)
    @Kosmo
    Although you have to wonder what allowance has been made for ground gear maintenance and for in-space repairs and maintenance.

    Other than manned space stations, the only thing that ever gets repaired in space is Hubble. Maybe if your power installation is a single entity, and the problem has put it completely offline, then it might make financial sense to go and repair it but it would have to cost a whole hell of a lot.
    • CommentAuthorlooneynerd
    • CommentTimeJun 26th 2009
     (2422.30)
    You also have a serious problem with space debris. Satellites get hit and pinged by stuff all the time. I can't imagine the fragile solar panels surviving terribly long, at least not without losing a ton of efficiency as the panels are scratched and cracked to hell by pieces of earth junk and meteorites.