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disco_tracy sent in a story about some fancy new power technology designed to tap energy from sound waves. Although the cell phone concept grabs the headline, they also talk about harvesting noise from traffic.

Comments

Lots of wasted energy

[bm_luethke]

There is a great deal of energy lost out there. Lots of heat, sound, inertia, etc that just bleeds away (well, at least with respect to forms we find useful). The question is can we *efficiently* gather it back up - not *can* we gather it back up. The same things goes with any recycling of "waste" products - it isn't always good to recycle them. Sometimes the wast products from capturing that energy is worse than letting that energy go away (I know for a long time the waste products from solar panel production/disposal were *significantly* worse than any carbon emissions you were saving) and sometimes it is cheap (and therefor mroe resources can go towards fixing the long term issue) to *not* recycle.

That's a good question for most "environmental" questions and it isn't easy. Lets take Corn based ethanol fuels - there are a number of studies out there that show it takes *more* energy to create them than if you just stayed with oil based products. The gains are probably not in that arena, they are either in emissions or dependence on a number of not so great human rights nations. Then we can take into account Wind Power - something that looks great in all these things. Well, that is, until you look at the impact on bird wildlife in those regions - is it worth the cost? Hard to say, if you are primarily worried about carbon emissions then very much so, if you are primarily worried about avian life then most assuredly not, if you want the best over all then all you pretty much get are both sides battling it out for which one is correct (and IMO neither one is).

So, if we cut carbon emissions by 50% but increase sulfur emissions by 15% to collect all this sound energy it isn't too good for us, though under certain people views that is a "win". I do not know and I'm not trying to say it is a good or bad (in this case there may be no downside whatsoever) idea - just that this article (along with the vast vast vast majority of environmental articles and studies out there) do not really address this well. In the long term we will bump against levels where we have to do this, but for right now we are still in an infantancy stage and we are better off looking for better processes than refining our current ones - unless our current ones are so bad that we need to refine them now (and energy loss to sound is minor compared to the rest of the system).