There is a big difference in relative kinetic energy for the air in Chicago vs the air in Dallas due to the parcels being at different lattitudes on a spinning globe.

This Delta-E is not insignificant.

If the air in Chicago could displace to Dallas in a frictionless pipe, it would gain that net relative kinetic energy due to centripetal acceleration. It would then just depend on the orientation of the pipe as to the relative velocity of the air when it emerged in Dallas.

Trying to send the air to Chicago from Dallas is a pipe dream, but going the other way could be a reality depending upon friction.

Sorry, I was wrong on calducutt. But – your tunnel approach is like the an OTEC system, except you are using a delta T of maybe 15 Kelvin to drive the airflow – and all that is doing is creating a pressure differential. So its back to Bernoulli. You won’t be able to generate much electricity out of a single bore – and you have completely ignored the point of how expensive it is to bore that tunnel, crosspatch. You’re ROI is close to infinity. You’d be better off putting windmills on the santa clara hills, in the few areas you can actually get decent wind energy, or better yet, off the coast, where there is good wind power all the time.
http://www.energy.ca.gov/maps/wind/WIND_POWER_50M.PDF

A tunnel from the Santa Cruz coast to the Santa Clara valley would pull in a large amount of coastal air during Summer when the valley temperatures would rise during the day causing a thermal low. Cooler (and wetter) air would then be pulled in through the tunnel from the coast. At night in Summer the flow would probably reverse by morning with cold air in the valley blowing toward the coast in a sort of “offshore” breeze.

Two other side benefits would be an increase in moisture in the valley and a ventilation mechanism for air to circulate during a temperature inversion that would otherwise cap stagnant air in the valley. It wouldn’t even need to be one continuous tunnel, it could be a series of tunnels through the various ridges between the coast and the valley.

To get an idea of what I mean, have a look some time in the evening driving along I-280 South of San Francisco at around SR92. The fog just crests the hills. If there were a tunnel through that mountain to the other side, Crystal Spring Reservoir might be covered a good bit of the time with a layer of fog that would cut down on evaporation saving a good amount of water. I think there could be lots of uses for strategically placed tunnels to get air to flow in certain ways with energy production being only one benefit. But I would say that the notion of long distance pipes is silly because the atmosphere already acts as a pipe connecting the two places together. It only works where the pipe provides a path that would otherwise be blocked, like with several thousand feet of mountain in the way. Then a short tunnel could have a great impact.

http://pesn.com/2005/08/11/9600147_Edison_Stirling_largest_solar/

Thanks for the kind words from Frank and the nice update by Mr. Watt.

Don’t get disallusioned! Energy is a function of what the public will pay. There is a lot of potential energy out there. We will not run out – but we may have rough patches. What we will do is transition in such a way that our overall costs are minimized (I don’t believe solar electric is in that catagory, by the way – too damn expensive – check out this site… http://www.solarbuzz.com/SolarPrices.htm – By the way, don’t confuse their “Solar 3″ with what I mentioned above – its a catagory…) Solar electric is mind boggling expensive…

Solar thermal is much better from a cost perspective. That’s why you aren’t seeing plans for a 4500 acre solar electic site…

“To understand how this works, just remember your childhood summer days playing with the hose in the yard… What happens when you make a smaller hole by nearly plugging the hose with your thumb…. The water spurts out ten times faster and farther! Our technology works on the same scientific principles…by focusing a lot of wind through a very small hole, it just gets faster and faster!”

Lol….. nevermind the disparity that the water in the hose has nowhere else to go, and the air has a billion better pathways, and unlike the water, the air could just reverse direction if it had to (ie by hitting a ‘plug’, it would rather turn around than exert enough pressure to get through)

As a mechanical engineer I appreciate you bringing folks back to reality with some of these wacky ideas. And thanks too for summarizing the most viable alternative energy sources we have at present. I am reminded that most of the ideas I see floated today are not new – in fact we have been researching alternative energy in this country for the better part of 30+ years! How long has NREL been around? Having said that, the fruits of that research have been improvements in materials and processes to the point that these technologies may now be economically viable.

Unfortunately, we will be seeing more of these wacky ideas as the global warming industry continues the panic the public into funding these things via government subsidies or a “carbon tax”. And there appears to be no end to the scare tactics the global warming industry will employ. Just today I saw a “news” article on how someone is now blaming global warming for the “reduced intensity” of the fall colors! Well, I live in NH and the colors here are quite beautiful this year – very intense reds on the maple leaves.

tThere is a natural gradient between mountaintop air and valley air which doesn’t fluxuate or change direction. Most of the cost of the Spanish thermal tower would be due to making the thing structural and safely free standing.
Instead of that we would run the pipe on the ground up the side of a mountain. It doesn’t have to be free standing or support it’s own weight so this gives us leeway over the materials used in the construction. It could be plastic, concrete, treated paper – whatever is most cost effective and weather survivable.
And there are large areas particularly along the valley side of the California Coastal Range where the hill country is contaminated by asbestos, the EPA won’t approve the areas for human use or habitation. It’s just sitting there unused and unusable.
Perfect for a heat pipe electrical generating plant.
This heatpipe windmill design removes the hippy/greenpeace/save the butterflies lobby because the birds won’t be killed in the prop.