New Rechargeable Battery Uses Water

fergus07 writes "Scientists at Stanford have developed a battery that uses nanotechnology to create electricity from the difference in salt content between fresh water and sea water. The researchers hope to use the technology to create power plants where fresh-water rivers flow into the ocean. The new 'mixing entropy' battery alternately immerses its electrodes in river water and sea water to produce the electrical power."

Just think of the possibilities!

[naich]

We could use the generated electricity to power desalinisation plants.

Re:Just think of the possibilities!

[ShanghaiBill]

We could use the generated electricity to power desalinisation plants.

I think you are trying to be funny, but this actually makes sense, and there are proposals to do exactly this. Here is how it works:

• Step 1: Concentrate brine in large evaporation ponds
• Step 2: Generate electricity from the osmotic difference between this brine and normal seawater
• Step 3: Use the electricity to split seawater into fresh water and brine
• Step 4: Recycle the brine back into the evaporation ponds
• Step 5: Profit!

The reason this works is that you are effectively collecting the solar energy that shines on the evaporation ponds.

Re:ALready an energy shortage there.

[gr8_phk]

I think he's talking about taking water and sending it to Arizona where it then evaporates in the desert and doesn't actually make it to the end of the river. I'm guessing of course. But as for these "inexhaustible" supplies under ground, you should read about the supply in the midwest [wikipedia.org] which requires drilling to new depths because it is being depleted. Should you think going deeper is always an option, you may want to read the recent stuff of fracking to see how the deeper water is being deliberately contaminated. There are solutions to these, problems, but what we are doing vs what we could be doing don't really match.

Re:Just think of the possibilities!

[trout007]

Not that this would be ecologically feasible but what if you dug a tunnel from the pacific ocean to death valley (-300 feet). Then you could get some power out of the potential water drop. Then as the water floods the valley it's so hot it would evaporate and you could keep letting the water in. The evaporated water would rain on the next mountain down wind and create arable land.