Flutterby™! : Perpetual Motion and Transit 2014-05-07 03:35:43.582597+00

Perpetual Motion and Transit

2014-05-07 03:35:43.582597+00 by Dan Lyke 6 comments

How the @#$%^&*( are these people still employed? Did Los Angeles Metro spend $600k to build a perpetual motion machine?. Someone noticed that subways push a lot of air, and thought "maybe we can put in a turbine to take advantage of all of that air".

“Some people have asked, well, gee, aren’t you going to have to use more power to push the train past this thing because of the interference it’s going to cause? Our belief is the answer is ‘no,’ because the machine itself doesn’t create as much of a barrier as the existing signs and electrical boxes that are already in the tunnel,” he said. “But that’s something that presumably needs to be studied more carefully to make sure you’re not creating more problems than you’re solving.”

The article, giving this guy the benefit of the doubt, does go into the ways that such turbines could be selectively switched and placed to grab power that would otherwise be wasted as heat, but...

The original article that Streetsblog pursued: http://thesource.metro.net/201...metro-explores-new-green-energy/

Oh, looks like WWT Tunnel is an organization set up to funnel taxpayer dollars into bullshit consulting projects. I wonder if that's the same California State Assembly Republican Member Frank Bigelow from the 5th District (O'Neals CA)?

#Comment Re: made: 2014-05-07 17:49:15.080789+00 by: meuon [edit history]

This is why basic physics and math classes should be required. Archimedes, Newton, and smart 10 year old kids should understand this one.

As a side note: I get approached about every 3 to 6 months in Chattanooga by someone with an idea that is essentially a perpetual motion machine/system ala: Steorn or weirder variations.

Before HSC Rohnert Park closed their doors, the (fairly knowledgeable) staff many times expressed their gratitude that I was asking for suggestions and advice for something other than building quack medical devices or perpetual motion machines.

It's actually an interesting question... A lot of air is displaced and vented, which already saps some power from the train. Adding a turbine may increase the back-pressure, but might also absorb some additional energy that's otherwise lost.

I think not. The only thing you can do with the wind turbines is increase the back-pressure, as the existing systemic back-pressure does not change after adding the turbines. End result: trains now require more energy to move while you only capture back a portion of that extra energy via the turbines. This is because the turbines are not 100% efficient, so you have a net energy LOSS.

There is no way this can possibly be anything but an expensive boondoggle. Absolutely no way, short of attaching a generator to Newton as he spins in his grave.

Mind you, I'd love to hear a reasonable explanation of why I am wrong about this.

Yeah, think about it the other way: Would it improve the train efficiency to evacuate the tunnel in front of the train? Yep.

The only way this makes sense is if you could use it for braking, but if you're going to do that you just do regenerative braking, with a hell of a lot less new machinery and intervening energy loss.