Molecules Can Store Solar Energy Indefinitely

Mashable ^ | 04/16/2014 | TODD WOODY

[SeekAndFind]

The next big thing in solar energy could be microscopic.

Scientists at MIT and Harvard University have devised a way to store solar energy in molecules that can then be tapped to heat homes, water or used for cooking.

The best part: The molecules can store the heat forever and be endlessly re-used while emitting absolutely no greenhouse gases. Scientists remain a way's off in building this perpetual heat machine but they have succeeded in the laboratory at demonstrating the viability of the phenomenon called photoswitching.

"Some molecules, known as photoswitches, can assume either of two different shapes, as if they had a hinge in the middle," MIT researchers said in statement about the paper published in the journal Nature Chemistry. "Exposing them to sunlight causes them to absorb energy and jump from one configuration to the other, which is then stable for long periods of time."

To liberate that energy all you have to do is expose the molecules to a small amount of light, heat or electricity and when they switch back to the other shape they emit heat. "In effect, they behave as rechargeable thermal batteries: taking in energy from the sun, storing it indefinitely, and then releasing it on demand," the scientists said.

The researchers used a photoswitching substance called an azobenzene, attaching the molecules to substrates of carbon nanotubes. The challenge: Packing the molecules closely enough together to achieve a sufficient energy density to generate usable heat.

It appeared that the researchers had failed when they were only able to pack fewer than half the number of molecules needed as indicated by an earlier computer simulation of the experiment.

[dhs12345]

Bummer. Good point. Frustrating. Because it would solve our energy problems.

[samtheman]

I hope I’m wrong. Fusion would truly make electricity “too cheap to meter”. Actually, that phrase was originally used with fusion in mind and then got misappropriated to fission, where it doesn’t apply.

[dhs12345]

Me too — I hope you/we are wrong. Containment is the issue because of the heat generated. Maybe they could come up with a way “control” the process much like control rods slow down the Fission reaction. Inject the plasma with an inert material that is stable at the high temps. Just a layman's ideas and I am sure that they have already thought of that.

I am not current on the technology other than I heard a few months ago that they were able to produce a net gain of energy. I think that they are shooting high power lasers at the core and igniting the reaction that way.

Another possible improvement: the heat is used to boil water and turn turbines. Maybe they should consider a process that excites electrons in a conductor and eliminate the steam turbine process all together. Maybe something that produces a massive magnetic field and eliminates the heat conversion process — much less heat, no spinning turbines, much more efficient, etc. Steam power is so 19th century. :)

[samtheman]

I know, it was big news about the net gain a few months ago, very close to “ignition”, but the “net gain” was very narrowly defined, measuring the energy of the laser beams themselves versus the energy output of the fusion, and there was a gain if you just looked at that comparison, but it ignored the total electrical power consumption of the laser devices, which was much larger than the fusion output. So there was a breakthrough of sorts but still far away from actual commercial power generation.

But we’ll see. A lot of clever people are working on it.

[dhs12345]

They are still years and years away. If they are successful, the tough part (not that it hasn’t already been tough) will be to build a practical implementation; a working power plant.

But I am crossing my fingers. We are going to need a lot more juice if everyone is going to be driving around in electric cars.