I am focused on this technology and believe central tower receivers with heliostats are the cheapest form of solar steam and power.  The technology deployed in Spain is old technology due to information inertia and consensus (like the IPCC.   Making the power via high-intensity pv instead of thermal turbines and using smaller mirrors with shorter towers, plus some clever mechanical redesign using the new low-cost abilities of micro controllers then the cost will indeed be three times cheaper, and cheaper than coal sans externalities around the world.

Littering acres with expensive and negative ROI producing solar panels
Thats Silicon solar.

Thinfilm CIGS panels are reaching a point which makes them look cheap compared to coal.

And if they could combine it with quantum dots, there'd be no holding it back.

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Lastly, an ROI doesn't make much sense if you're comparing it to burning Coal with Carbon Capture and Sequestration  AND IGCC.

Since the cost of that would make even silicon solar look cheap.

Is this really possible?:

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The vision is of the sun-blessed lands of the Mediterranean - even the Sahara desert - being carpeted with systems like this with the power cabled to the drizzlier lands of northern Europe. A dazzling idea in a dazzling location.
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If "cabling power" can be done, practically, well then, it should be observed that there are plenty of "sun-blessed" areas in the southern US where a concentrated-solar-power project might be tried.  E.g., Imperial Valley, CA, which would be much better off converted from being an agricultural center -- it requires obscene amounts of channeled Colorado River water in order to get anything to grow in that desert -- to being a CSP generator supplying, say, San Diego.

As a point of cultural trivia, we might remember that back in the early Middle Ages, Islamic civilization was at its height, Arab scholars and scientists were preserving the achievements of classical (Greek) scholars and scientists, and building on them, and Western Europeans were relatively backward.  One of the sciences that the Arabs advanced is astronomy; another is optics; another is the mechanics involved in the movement of water and the harnessing of water power.  And so it is quaintly appropriate that one of the most brilliant centers of Arab culture in Spain, Seville, should now become the site of this CSP project, which involves all those disciplines.

Chickens are our cousins! So are other sensitive animals! Enough is enough! No more factory farms!

Oddly, I'm less interested in CSP in warmer regions

And more interested in geothermal in colder regions.

The idea being you get easy access to really cold water to run the opposite side of the T-low + T-high engine.

Right, Grey Falcon, geo-thermal is in principle as promising as solar.  This planet's heat, beneath the surface, is immense.  But as with solar, the ways of collecting that energy, as currently understood, are obstructed by technological limitations.  Still, for those with vision, the ability to think outside the box, and the guts to make a huge initial investment, my feeling is they should go for it: "Build it, and they will come."

Chickens are our cousins! So are other sensitive animals! Enough is enough! No more factory farms!

Thanks, Grey Falcon, I did the CalEnergy virtual tour: not nearly so cute as the one in "Jurassic Park" -- but after all, John Hammond (Richard Attenborough) "spared no expense" -- , and yet very well done.

Probably people who understand these things, totally unlike myself, can comment on how sustainable it truly is, to be relying on drawing up the subsurface superheated water, then sending it back down again.

Whether or not this method of harnessing geothermal energy is sustainable, it illustrates what I mean when I say "in principle," vs. "inside-the-box thinking."  The heat is really there, the magma is really there (and that is in the mantle, I think, not the core, which is what the CalEnergy tour says).  The superheated water is as it were an accidental by-product of the conditions of Earth's crust and mantle, which happens to be currently utilizable.  And absolutely, that resource should be carefully managed and utilized.

But really, when we say "geothermal," we should not be restricting ourselves to talking about the superheated water.  We should be talking about the magma itself.  We should be engineering some energy collection device that can be thrown down the throats of volcanoes.

Chickens are our cousins! So are other sensitive animals! Enough is enough! No more factory farms!

Except that you can't combine a stirling dish with anything.

You'd need to make some sort of elaborate trough based solar.

And past that, you'd also need to get the snow off of the panels, which could easily break curved mirrors.