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Thread: i had this idea for energy storage

  1. #1 i had this idea for energy storage 
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    i was having a discussion with others about renewable energy and how batteries are the biggest pain in the rear when discussing off the grid production and storage of electricity.. so i had this idea and id like to know what others here think

    electric motors simply act as a device to convert electricity into mechanical energy, but mechanical energy can be put into an electric motor and be converted into electricity.. and with water turbines and wind turbines this is what happens

    so my idea is about storing the energy you create to use at a later time.. batteries are expensive, they degrade, they weigh a ton, and they can be dangerous and realistically are only needed when mobility or size constraints are necessary.. you can power electrolysis to create hydrogen gas from water and burn that in an ICE engine or fuel cell to get electricity back, but my idea uses gravity

    my idea is to generate the electricity by whatever means, it doesnt really matter be it wind turbines, solar panels, whatever.. but have that energy turn an electric motor which will actually turn a winch, this winch will lift a massive weight.. maybe a big barrel filled with concrete, and lock the weight in place at its apex.. then when power is needed back, the weight is released and begins to fall, turning a couple gears which in turn spins the generator to power your house.. obviously gears would be needed so the electric motor could provide the winch with enough torque to lift the barrel, but at a much slower rate

    now, for this to work a few things would need to be determined.. how much power you want produced at once, how fast the generator would have to turn to produce that amount of power, how heavy the weight is, and then you can determine the gears necessary to make it work, and how far the weight has to fall.. so theres obviously a bit of math here, and youre never going to get a 100% return on your investment (due to electric motors not being 100% efficient, though neither are batteries).. but in the end i think it could work..

    likely youd need atleast SOME batteries to be used as a buffer since your power consumption is going to fluctuate, itll never be a constant, but your really small battery bank can store maybe 6 hours worth of energy you could probably automate it so that when those batteries reach 20% level, a break is released to let the barrel fall another couple feet to recharge them before stopping again, allowing those batteries to work as a buffer

    what do you guys think of this idea?


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  3. #2  
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    Quote Originally Posted by justin22885 View Post
    my idea is to generate the electricity by whatever means, it doesnt really matter be it wind turbines, solar panels, whatever.. but have that energy turn an electric motor which will actually turn a winch, this winch will lift a massive weight.. maybe a big barrel filled with concrete, and lock the weight in place at its apex.. then when power is needed back, the weight is released and begins to fall, turning a couple gears which in turn spins the generator to power your house.. obviously gears would be needed so the electric motor could provide the winch with enough torque to lift the barrel, but at a much slower rate
    . . .
    what do you guys think of this idea?
    No theoretical problems provided you have enough weight, distance etc. But you need a lot of both. For example, if you want 10 kilowatt-hours of storage (which is what a really efficient house uses in a day) you need 14,000,000 foot-pounds of storage. Let's say you have a barrel with 10,000 pounds of concrete in it; you would have to lift it 1500 feet in the air.

    I'll go you one better. Buy a few electric locomotives, find a deserted track up the side of a mountain and get a train full of gravel. Use power to drive the train up the mountain, then allow it to descend and generate power. Same basic idea but everything is off the shelf. A Bombardier IORE 101, for example, will give you 10 megawatts per locomotive.


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  4. #3  
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    yeah.. i just ran some calculations myself.. the average household runs on 40 kilowatt hours a day, even if your house is super efficient running on 20 kilowatt hours a day it translates into 50 million foot pounds of energy.. realistically such a weight could only drop maybe 50 feet if you dug a hole for it youd still need 500 tons of weight.. concrete is 150 pounds per cubic foot, this would require 6,666 cubic feet of concrete, which lets say a 10x10 foot mass was created it would have to be 66 feet tall and need an absolutely massive crane to lift it

    any other ideas for an alternative to batteries for renewable energy storage?
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  5. #4  
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    any other ideas for an alternative to batteries for renewable energy storage?
    Better batteries? New technologies.

    Reposting: Don Sadoway on Energy Storage | Climate Denial Crock of the Week
    "Courage is what it takes to stand up and speak; courage is also what it takes to sit down and listen." Winston Churchill
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  6. #5  
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    Quote Originally Posted by justin22885 View Post
    any other ideas for an alternative to batteries for renewable energy storage?
    Supercapacitors, and they are already being used.
    Supercapacitor - Wikipedia, the free encyclopedia
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  7. #6  
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    i looked into supercapacitors though but the cost negates any benefits

    another idea is the fabrication of some large fuel cells dipped in water.. when electricity is supplied the water splits into hydrogen and oxygen.. when the current is removed the hydrogen and oxygen recombine into water and generate electricity.. what i would need to determine is what kind of fuel cells can i purchase and for how much, how much power will actually be lost on the round trip to determine how much energy a renewable energy system would have to generate to make up for it.. also, i should probably try my hand at making some homemade fuel cells
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