Energiestro (store energy by inertia in concrete)

[ENERC]

What do you want to bail out the Titanic?

I was thinking about the reuse of ships that are going to scrap.
For example a small tanker of 50 000 tons. The tanks are cleaned, the attachment points are set and the 60 000 m3 are filled with non-recyclable recovery glass (too dark) or with dense rocks such as granite (density around 2,5).
The effective weight would be 60 000 * 2,5 - 50 000 (Archimedean thrust) = 100 000 tons.

With Uranium from the Hague (19 density), it's better, but I'm going out ....

The conversion efficiency will be very good, like 90% for a motor / pulley / cable system.

To avoid a depression of the ballasts due to friction when we go up the load, it is necessary to work at low speed 0,1 m / s, which is still 100 MW with my example of tanker recovery.

Side resource, in France we have only towards the Cote d'Azur with 500 1000 meters or further ratings in the Biscarosse pit https://www.geoportail.gouv.fr/donnees/ ... nds-marins

On lower depths, we have the old offshore oil wells that could be recycled.

[Remundo]

absolutely, an old boat filled with stones it will make tonnage

I still see a disadvantage, it will be necessary that these masses, whatever their natures, move slowly in the water, because the hydrodynamic friction could be very penalizing.

[Christophe]

that said, 10 kg of concrete, it must always be cheaper than 500 g of batteries.

Not at all if you count everything there is "around" the concrete and which allows to generate current ...

In addition, Archimedes' thrust must be taken into account: out of the 100 T of concrete for the project, which has a volume of 40m3, 40 Tons will therefore be "useless"!

The solution of the bell posted by Izentrop seems smarter (and nothing prevents to do it in concrete too) provided that the energy costs of pumping air to raise the bell are lower than those of a simple winch ... And here I still have no answer

[izentrop]

The solution of the bell is much smarter!

Yes it would be enough to moor the wreck upside down. A pipe connected to a liquid piston pump on the surface, it seems to me that installation costs should be much less, provided that the performance is at the rendezvous.

https://www.energiesdelamer.eu/publicat ... 6-stockage

[Christophe]

Yes, except that a "semi-rigid" solution is less resistant to storms ...

On the performance I always expect the energy cost of pumping 40 m3 to 200 bars
This will give us an interesting markup ...

If no one wants to stick to it ... Are there no divers here? How much does a dive compressor consume? How many € do dive clubs charge to compress L?

[Christophe]

I still see a disadvantage, it will be necessary that these masses, whatever their natures, move slowly in the water, because the hydrodynamic friction could be very penalizing.

Yes but they are pretty easy when you know the shape, viscosity and density of the medium and speed ...

A too slow speed would have no interest because the principle is to absorb the peaks (that it is with the storage or the destocking of energy) ... See my calculations of corner of table higher ...

In short, the more you think it looks like an FBI ...

[Remundo]

Yes, except that a "semi-rigid" solution is less resistant to storms ...

On the performance I always expect the energy cost of pumping 40 m3 to 200 bars
This will give us an interesting markup ...

If no one wants to stick to it ... Are there no divers here? How much does a dive compressor consume? How many € do dive clubs charge to compress L?

in coarse approximation, you can do P x V: 200. 10 ^ 5 x 40 m3 = 800 MJ = 222 kWh. In practice, it is less because the first volumes of compressed air are not "pushed" to 200 Bar. Maybe let's say 100 kWh

in comparison, 100 tons of concrete on 4000 m store 4 GJ = 1 111 kWh

we would be at 10%, it's significant.

[Christophe]

Oh no! At 4000 you have to compress 400 bars not 200 bars..if you swell nothing at all ...

And you do not take into account the buoyancy of Archimedes?!?

100T concrete (40m3) will only weigh 60T in the water ... either (see above) 330 kWh 2000m ... if it takes 222 kWh to go up with air then it's more interesting to inflate than to shoot with a winch ??

We earn 110 kWh each cycle and we invented a perpetual movement!

Good without laughing, would need a more precise formula ... normally it goes through an integral with possibility of recovering the bars (buffer tank) on the surface as the mass goes up ...

[ENERC]

We come back to the effectiveness of isothermal compression. We already had a lot of pages on it, did not we? (the post on liquid nitrogen ....).

It does not need any contact between the water and the air under pressure otherwise it will freeze to the relaxation - it is a well known problem of the divers: air a little wet = ice in the regulator.

[Bardal]

Just two or three thoughts around a problem that I confess I can not solve (the compression will it be adiabatic, or not, etc ...)

- at 400 bars, the air density is 400 times that at 1 bar, it weighs about 500 kg at m3

- it will therefore be necessary, to reassemble 100 tons of concrete (therefore 60 tons of force to be supplied) approximately 120 m3 of compressed air at least, or approximately 480 m000 of "atmospheric" air, which, over its 3 km route , will have had plenty of time to cool down ...

- on the ascent, this air will tend to resume its initial volume, and thus to escape the balloon, while cooling for simple reasons to understand; I hope it will not cool too quickly (at 4000 m, the water temperature is very close to 0 ° C), as this may cause some problems.

- in any case, the energy to be supplied to compress this air at 400 bars can not be less than the work it will provide at the ascent; as already said, the perpetual movement does not exist, and there is moreover multiple leaks of energy in this machinery, which seems to me astonishing, conceived by an engineer ...


I did not address the many questions posed by the aggressiveness of the marine environment, both physical and chemical, or biological (see pbs encountered by tidal turbines recently) ...