Query for Physicists and Engineers - Extracting Energy from Atmosphere

Atmospheric Cold Energy
Is it possible to extract meaningful amounts of electrical energy from the air pipeline conduit described in Patent No. US 6,696,766 B1 Feb. 24, 2004.

US 6,696,766 B1

The patent shows a pipeline about 200 miles long from the NW corner of Oregon across a portion of Nevada to a point on the border with Utah. Mountainous terrain, and differences in altitude to contend with.

Operation is dependent on a differential in atmospheric pressure between inlet(s) at higher elevations and that at the air turbine outlet at the lower/lowest elevation.

Having studied the patent can you prove that it is a viable design or prove it is not and why?
How would year around weather conditions affect the cost of design and construction? e.g. Solar insulation, snow loads. Others?

If they were trying to use a temperature difference, there’s a chance it might conceivably work. It’d be horribly inefficient, and there’d probably be no way to make it return even a fraction of the investment costs, but it might work.

But the pressure difference? There’s a difference in pressure between different elevations for a reason. The pressure differences are exactly enough to counteract gravity: If you try to move air uphill to even out the pressure, you’ll end up losing more energy to gravity than you gain from from the pressure (and vice-versa: If you try to move air downhill, you’ll lose more to the pressure than you’ll gain from gravity). If you build a pipleline from the bottom of a mountain to the top, the air in the pipe will (on average) just stay still, just like the air outside the pipeline (you’ll get some fluctuations, but you get that outside the pipe too: It’s called wind).

Windmills exploit the pressure differences that drive winds in open space. Such pressure differences exist and would drive air flow through pipes, too, but not very well.

But I didn’t study the patent.

Well yes. I’ve gone through all that. The inventor’s premise is that he can exploit the differences in barometric pressure at the inlet area some 200 miles away from the outlet. His expectation that this would supply a sufficient difference in pressure to drive the turbine to extract signifigant power. All based on historic weather bureau data. This data of course is likely averaged, and the vagaries of weather being what they are there is nothing stable nor continuous as far as the barometer or atmospheric pressure is concerned.
My conclusion is the the inventor was deluded, incompetent or a scammer deluxe.
A tall vertical pipe or one with little horizontal distance from inlet to outlet is of course a trivial and obvious case of non-operation.
Perhaps someone will post some additional solid reasoning as to its usefullness.

The pressure difference due to barometric pressure is real, and in (myopic) theory usable. That due to altitude is not. Essentially, air is piling up in the high pressure area.

In practice there will be no usuable pressure difference at any useful flow rate. Air flow in a duct is similar to current flow in a wire. At 200 miles length, the duct would require an impractically large diameter to avoid flow induced pressure drop. Electrical systems counter this effect by increasing the pressure and decreasing the flow using transformers which operate at highe effiency. There is no similarly efficient pneumatic analog to an electrical transformer.

On page 3, he shows that his power estimates are based on the assumption that pressure differences (which we can gnerously estimate to be on the order of 1 inch of mercury (25 mmHg or 3.4 kPa or 0.5 psi) will generate flows of 550 mph. this is like saying that if you put the engine and propeller from a very fast prop plane in a pipe connecting two chambers, it couldn’t generate nearly enough air velocity in the pipe to sustain a 0.5 psi difference. (The FAI lists the fastest standard propeller plane as falling just short of 370 mph).

Hurricanes don’t come close. The fastest wind ever recorded was [rl=http://www.mountwashington.org/about/visitor/recordwind.php]234 mph gust on Mount Washington in April 1934 (not, as some believe, “in the Marianas trench in 1960 for about 15 min”)

Sadly, any kid with a good set of lungs, a plastic bag and a barometer can disprove that assumption. So can any parent inflating party ballons. An ordinary soda can is estimated to have, not 0.5 psi net internal pressure, but 60-80 times as much. I’d be afraid to open one of those jet-engines-in-a-can, wouldn’t you, Jimbob? Why I shudder to think what would happen to anyone who let the air out of a tire (up to 100psi or more for bicycle tires!)

Basically if he was perfectly correct everywhere else, he needs to sanity check the actual pressure difference he’s working with. Even without the pipe, it’s diddly.

As others have stated this simply won’t work. I’ll add another reason. With a 200 mile pipe you are going to have significant temperature variations in the pipe due to the outside temperature. It’s likely that these variations will make it impossible to get any sort of useful flow on the pipe. Not that I think you could get useful flow even without temperature difference, but it’s another reason why it won’t work.

I don’t see thatr anyone else has tried inquiring further, but if you google up the inventor’s name you find some interesting websites. Evidently they’ve startede up a company devoted to implementing this. I don’t know if they really think this will work, or are a high-concept con game, but it’s interesting to see:

http://www.coldenergyllc.com/default.htm

http://pesn.com/2005/10/27/9600188_Atmospheric_Cold_Megawatts/

http://www.rhfweb.com/keeltytech.html

http://peswiki.com/index.php/Directory:Barometric_Pressure_Power

It was prior to issuance of “The Patent” that I first ran across the inventor and his claims of generating signifigant, read MegaWatts, of power from atmospheric pressure differences. Thought it was a crock then and current consensus indicates the same. Some of the links in the above sites have links to “free energy sites” which is another negative association.
An inquiry to ACM resulted in a brief and less that candid reply. They seem to rely heavily on having a patent for the system as a selling point.
Any patent, however, is only worth what it can be traded for in terms of financial gain else it it just a piece of expensive paper (legal fees etc.)