Energy Vault – Gravitational Batteries
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Energy Vault – Gravitational Batteries
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Re: Energy Vault – Gravitational Batteries
#2Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights.
I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000.
35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH.
I'm generous and assume that the tower is 100m high. I haven't seen a real number on the website.
It's possible that they are using a cheaper material mix but that's the entire problem. What materials are they using? They never say so on the website. This is not rocket science. We are merely talking about how to build the cheapest 35 ton rock on earth and yet these people are silent about that.
Re: Energy Vault – Gravitational Batteries
#3Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…
But each weight can be reused almost infinitely... The cost doesn't matter too much.
Re: Energy Vault – Gravitational Batteries
#4Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…
This was already busted by Thunderf00t:
https://www.youtube.com/watch?v=NIhCuzxNvv0
Re: Energy Vault – Gravitational Batteries
#5Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…
> This is not rocket science.
it is literally rock science ;)
Seriously, in Germany, concrete costs arount 100 EUR per cubic meter. So we would end up with around 150 EUR per kwh capacity. But they would not have to use concrete for the task. They could as well use 23 m^3 gravel (which goes down to 10EUR) and some steel scaffolding. Or even just plain water (35m^3).
Re: Energy Vault – Gravitational Batteries
#6Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…
> What materials are they using?
"Just Have a Think" put out a video about this recently [1]. The project he reports on claims 30MW with 4MW available within 3s for frequency stabilization and the weight is not solid concrete (emissions penalty), but rather compressed refuse that otherwise cannot be recycled (coal ash, demolition debris).
The friction would occur as long term tensile strength durability of lifting cables and high torque electrical hoists, which are the primary material penalties. But these things may be relatively cheap to produce and rotate out of service as their known operational lifetime approaches (Tesla has designated labor that changes out public charger cables within a reasonable buffer before they are expected to wear out).
Re: Energy Vault – Gravitational Batteries
#7Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…
But each weight can be reused almost infinitely... The cost doesn't matter too much.
That's not right. Refinforced concrete will suffer from environmental influences and have a durability from maybe 30 years. That means you have a cost overhead of 3-4% per year for the replacement value.
Water tanks certainly have a much worse life time, given that they will start lacking after a short time and you don't only have to repair the tanks but also provide liquid to refill.
Re: Energy Vault – Gravitational Batteries
#8This is the best thing, a lot of waste can be repurposed as well
Re: Energy Vault – Gravitational Batteries
#9This giant crane with three arms looks like something you would climb in a FPS stealth game (dishonored 2, deus ex series, etc). Of course it would be populated with various difficulty levels of private military company henchmen.
Re: Energy Vault – Gravitational Batteries
#10Building cranes is most the boring part of this project. It's far more interesting to know how they are going to make the 35 ton weights. I don't know anything about the construction industry but some googling showed that 1 m^3 of concrete weighs 2.4 tons. You will need 15 m^3 weights. 1 m^3 costs $200 so each weight costs $3000. 35000kg×9.81m/s^2×100m is 34335000 Joules or 9.5kWH. $3000 / 9.5kWH is $315 per kWH. I'm…
I wonder how they've calculated the costs of building this giant crane and concrete block system, vs building small scale pumped storage hydroelectricity. Not by the usual method of impounding a reservoir at the top of a hill, but putting a giant array of load-balancing medium sized water tanks at the top of a hill, running a pipe to the bottom where there's the pump/generator, and a similarly sized array of tanks.