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Gravitricity

gravitricity.com

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Re: Gravitricity

#141

Post by [deleted] »

bduerst wrote: post #139
jmadsen wrote: post #133

I love how every Tom, Dick & Harry with a bit of math & engineering thinks he can "dispel the myth" of HN Idea X with two minutes of off-the-top-of-his-head equations. Read about these two: http://www.gravitricity.com/#people Do they seem like complete morons? Do you think they haven't studied this just a little bit more than you have? It doesn't mean their idea is good or will work - just that you aren't going to ri…

You don't need to be a carpenter to tell if a house is built poorly.

[deleted]

Re: Gravitricity

#142

Post by jmadsen »

bduerst wrote: post #139
jmadsen wrote: post #133

I love how every Tom, Dick & Harry with a bit of math & engineering thinks he can "dispel the myth" of HN Idea X with two minutes of off-the-top-of-his-head equations. Read about these two: http://www.gravitricity.com/#people Do they seem like complete morons? Do you think they haven't studied this just a little bit more than you have? It doesn't mean their idea is good or will work - just that you aren't going to ri…

You don't need to be a carpenter to tell if a house is built poorly.

You don't need to be a carpenter to tell if the doors are hung straight.

You DO need to be one to actually assess the overall build and structure.

Re: Gravitricity

#144

Post by cdoxsey »

Coincoin wrote: post #59
mikeyouse wrote: post #30

Earlier quoted context omitted.

In 2011, we mined 0.2% of known lithium reserves.. This would provide over 350 years worth of lithium at current rates. Obviously usage is dramatically increasing but so will our known reserves as the overall level of demand increases. This is also without developing a method to pull the relatively abundant lithium from sea water and without recycling any lithium we're currently disposing of. Ambri is interesting fro…

"The greatest shortcoming of the human race is our inability to understand the exponential function."

Except all those dire predictions turned out be wrong. We didn't run out of food or resources, and birth rates have now declined in almost every country in the world. Population growth is basically now a complete non-issue. In retrospect, ignoring the Paul Ehrlichs of the world turned out to be the right move - a far cry from mankind's greatest shortcoming.

If we run out of lithium we'll figure something else out, just like we would for any other resource.

Re: Gravitricity

#145

Post by tempestn »

dgemm wrote: post #114
dools wrote: post #101

Earlier quoted context omitted.

It looks as though compressed air is a key component.

It's not.

It's not a key component, but it is a significant benefit of their system. The main reason though is that the primary benefit of this system is flexibility of placement. By locating grid storage close to where it's used most, you save significantly on transmission losses (and infrastructure). Finding sufficient vertical cliffs would be even more difficult than finding suitable locations for pumped hydro.

Also if you expose the weight to open air and wind the whole system would be much trickier than using an enclosed shaft.

Re: Gravitricity

#146

Post by notatoad »

bduerst wrote: post #139
jmadsen wrote: post #133

I love how every Tom, Dick & Harry with a bit of math & engineering thinks he can "dispel the myth" of HN Idea X with two minutes of off-the-top-of-his-head equations. Read about these two: http://www.gravitricity.com/#people Do they seem like complete morons? Do you think they haven't studied this just a little bit more than you have? It doesn't mean their idea is good or will work - just that you aren't going to ri…

You don't need to be a carpenter to tell if a house is built poorly.

There's a lot of things more complicated than building a house.

Re: Gravitricity

#147

Post by tempestn »

bequanna wrote: post #126
michaelbuckbee wrote: post #100

This is just rampant speculation - but what if they used depleted uranium as the weight? They could get paid to take the material off others hands (instead of buying lead) and it's almost 70% more dense.

Wouldn't the initial cost savings be offset by the ongoing challenges of dealing with a big moving chunk of hazmat?

Probably... but it's still an intriguing idea! Especially since their pressurized gas proposal already calls for a sealed cavity; maybe there actually is potential there. (Of course, there would probably be a significant PR cost too.)

That said, they can already get more weight by making the weight taller, so density likely isn't a huge benefit. Whatever's the cheapest cost/kg (and without the other issues of Uranium) would probably be best.

Re: Gravitricity

#148

Post by callmeed »

Funny, I just finished Peter Thiel's book. In the final chapters, he discusses the cleantech flame-out companies of the 2000's and how many were run by old suits. He contrasts them with true technology innovators (like Elon) who are "t-shirt and jeans" people.

Interesting to scroll down and see suits at this site.

Re: Gravitricity

#149

Post by HarryHirsch »

mikeyouse wrote: post #30
troymc wrote: post #17

Earlier quoted context omitted.

That's true. Unfortunately, current Tesla battery packs use lithium, which isn't super-abundant in Earth's crust. That's why companies like Ambri are looking at using other materials in the batteries they're developing for grid energy storage.

In 2011, we mined 0.2% of known lithium reserves.. This would provide over 350 years worth of lithium at current rates. Obviously usage is dramatically increasing but so will our known reserves as the overall level of demand increases. This is also without developing a method to pull the relatively abundant lithium from sea water and without recycling any lithium we're currently disposing of. Ambri is interesting fro…

For peak storage, vanadium accumulators are well established. Lithium cells give you an advantage in density, but for peak storage you are looking at capacity first, and then you consider the footprint. With vanadium you are only limited by the size of your electrolyte tank. The additional advantage is that vanadium reserves are much greater than lithium reserves.

Re: Gravitricity

#150

Post by jakobegger »

joering2 wrote: post #140

I have this idea in my mind for a while now and it seems great subject to share it with you. Imagine an elevator going kilometers into the oceans dept. A huge tank is mounted on the top of it. It gets filled in with pressurized air. Because its heavy it sinks to the bottom. Then an air is released. Air travels into the surface but on its way it is actually captured into a little traps. When enough air is trapped, the…

The deeper you go, the higher the pressure. The higher the pressure, the smaller the (trapped) air bubbles. The smaller the air bubbles, the lower the upward force.

As a result, the deeper you go, the more air you will need to pump into your tank.

Or in other words: with a given amount of air inside your tank, there's a maximum depth you can go. If you go deeper, the air bubbles will no longer lift the tank.

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