At the Brave New Climate blog, there is a thread running on energy storage right now. One of the comments in that thread pointed to the “Energiespeicher” blog by German professor Eduard Heindl. I just added a permanent link to that blog (it is in German language).
“Energiespeicher” means energy storage, and professor Heindl has an interesting idea he calls “Lageenergiespeicher”, which might be translated as “Sysiphus” into English, or “statusenergystorage” for a more direct translation. He wants to cut out a VERY BIG ROCK out of a mountain and float it on water.
That would seem to get much more storage power per square meter of area used. A rock 500 meters in diameter and 1000 meters in depth would yield 1.7 TWh in storage capacity, using less than 1% of area and costing less than 10% compared to pumped hydro.
That blog has some other interesting information as well. The latest post points out that there now is a simulator running at David McKay’s “withoutthehotair” website where everyone can try to build their own energy system for the United Kingdom.
I don’t get this rock thing, it seems to me it just can’t work.
If the density is higher than water, then it won’t float and we can’t use water to move the rock around.
If the density is lower than water then it can float, but the mass is the same as the one of the volume of water it removes (just applying Archimedes’ principle here) so there’s no actual interest in doing that, the energy storage capacity of the rock (it’s mass) is the same as the one of the water you can’t store anymore in that reservoir because there’s no room anymore for it.
The rock does not float on or in water, but is pushed up, just like the shaft in a motor. Therefore, gravity will work to push the water out again, if the operator wants that to happen.
If they can pull that off, I assume they might get some interesting extra revenue from tourists who come to look at the moving mountain. Someone already suggested building a hotel on the rock…
I would built a Kitegen Carousel…like 2-3GW on top of it. When the rock raises you get to tap into even higher winds
A noflight zone would probably be required anyways.
Interesting, I never heard about that before. But I agree, it would be a good idea to have some wind generators on the top, as well as solar panels everywhere.
Maybe they could even get away with plastering the sides of the cylinder with solar panels, just for the hell of it.
[...] have blogged about this concept before, in November 2011. I like it. As Heindl explains in this talk, it is cheap (per kWh), has a high [...]
[...] have blogged about this concept before, in November 2011. I like it. As Heindl explains in this talk, it is cheap (per kWh), has a high [...]