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Thread: Using gravity for energy storage

  1. #1
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    Default Using gravity for energy storage

    Has anyone ever used a large weight to store energy instead of batteries?

    For example, install railroad tracks up a steep hill and put a railroad car filled with heavy boulders on the track. Use daytime solar to run a motor to slowly pull the car up the STEEP hill. Then, motion of the railroad car down the hill would be geared up and run a generator. It works in my Grandfather's clock.

    Since 1 HP is 550 ft-lbs/sec......

    If the railroad car weighed 550,000 pounds (275 ton) and descended 1 vertical foot every 100 seconds, it would generator 10 HP or 7 KW (not counting conversion losses)

  2. #2
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    Same thing as water tank or pump back lakes. There are so many losses and such huge volumes of weigh and area needed it is pointless. However works great with something like a grandfather clock.
    MSEE, PE

  3. #3
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    The amount of weight you need to move is too much for anything except that grandfather clocks.

    This has been studied for the past 100 years or more and is documented on the web.

    Kind of like the water storage thing - very large weights rather than very large volumes.

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    Quote Originally Posted by Perry View Post
    Since 1 HP is 550 ft-lbs/sec......

    If the railroad car weighed 550,000 pounds (275 ton) and descended 1 vertical foot every 100 seconds, it would generator 10 HP or 7 KW (not counting conversion losses)

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    [QUOTE=MarineLiner;20849]

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    Quote Originally Posted by Perry View Post
    Well it would take more than 7000 watts to pull the weight up (at the same rate) unless you don't believe in conservation of energy.

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    [QUOTE=MarineLiner;20849]

  8. #8
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    [QUOTE=MarineLiner;20849]
    MSEE, PE

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    Quote Originally Posted by Perry View Post
    It would take 1 watt to move 1 KG up one vertical foot in 100 seconds not including friction and conversion losses.

  10. #10
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    [QUOTE=MarineLiner;21038]

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