Hoover dam as giant battery

[cRiPpLe_rOoStEr]

Originally Posted by Angel And The Wolf

It would be better to just add the solar created electricity to the grid. The conversion of electricity into mechanical energy nets a loss in efficiency.

Sure. Well, even though the idea sounded somewhat interesting, it didn't seem practical at all.

When it comes to storage of that solar energy, lead-acid batteries still seem to be the most cost-effective option, even though I'd probably prefer spiral-plate ones such as those Optima instead of conventional ones.

[freebeard]

Originally Posted by oil pan 4

What batteries?
If battery resources are diverted to grid storage then there won't be enough battery materials to build electric vehicles.
A big, heavy, low density, cheap, common material, thats also efficient like a lithium battery needs to be developed.

https://duckduckgo.com/?q=wood-tin+battery&t=h_&ia=web

[California98Civic]

Originally Posted by NeilBlanchard

I learned more about this Hoover Dam as pumped hydro storage proposal - and it is wrong headed. It might sound good, but we can do much better, for less money, and with almost no downsides - with battery storage.

Graphene to the rescue! But seriously... what did you read on the dam project?

[redpoint5]

Graphene (and carbon nanotubes) is supposed to make everything in the future thousands of times better than now, but what is holding it up?

Where are the super strong carbon nanotubes capable of ridiculous tensile strength (space elevator)?

Where are the graphene batteries that prevent dendrite growth and create a puncture-safe cell?

Where are the "warm" superconducting wires?

Supposedly every area of life should be improving due to graphene and carbon nanotubes, but so far all I've got is very expensive supercapacitors.

[oil pan 4]

Those sound pretty good.
But has anyone built a full size battery. I'm not talking grid storage scale but maybe big enough to use for an off grid house, in the dozens of kwh range?

Lead acid could work because lead acid batteries are the most recycled item on earth. Reliably is good but their efficiency kind of sucks.
If I went off grid tomorrow I would be ordering some sort of lead acid batteries.

[jjackstone]

Originally Posted by redpoint5

Graphene (and carbon nanotubes) is supposed to make everything in the future thousands of times better than now, but what is holding it up?

Where are the super strong carbon nanotubes capable of ridiculous tensile strength (space elevator)?

Where are the graphene batteries that prevent dendrite growth and create a puncture-safe cell?

Where are the "warm" superconducting wires?

Supposedly every area of life should be improving due to graphene and carbon nanotubes, but so far all I've got is very expensive supercapacitors.

All these things are in the same place as nuclear powered flying cars, home nuke plants, and living on the moon were 60 years ago. Only 50 to 100 years away. JJ

[jamesqf]

Originally Posted by oil pan 4

But has anyone built a full size battery. I'm not talking grid storage scale but maybe big enough to use for an off grid house, in the dozens of kwh range?

Yes. Tesla Powerwall, 13.5 kWh

[redpoint5]

I'm always a fan of smallish tweaks to something that enable them to be dual use.

Putting power walls in every home seems inefficient.

However, if EVs really catch on, we could incentivize owners to have them grid connected to absorb excess renewable generation, and to supply the grid when demand is greater than production capacity.

Would be neat if someone would do a study on the feasibility of a system like this, along with projected costs, and the amount of EVs that would be necessary for a robust grid buffer.

[Piotrsko]

Problem with powerwalls is they use lipo technology, so we are back to the use of rare metals with no recycling.

I believe the study with vehicle packs was done, but the source was biased IIRC and the conclusions suspect. Kinda big losses going back & forth between wall and pack.

There are many homes with whole house lead acid batteries in the 20+ kwh range in use right now.

[oil pan 4]

The vehicle to grid thing is dead as far as I can tell.

If the power wall uses these cheap sodium tin wood batteries why is it just about the most expensive way to get 13kwh of storage anyone has yet devised?
Plus I thought I read that the power wall uses some traditional Li-ion chemistry, which means it uses cobalt.
I made a post about cobalt in the fossil fuel free forum a fee days ago about all the problems with cobalt.

Plus 13kwh is kind of useless for off grid. I would be looking at installing at least 100kwh if I were to go off grid.