June 12, 2012
We set out Tuesday for Seville. On the way we went by a large solar array. Hundreds of large mirrors (heliostats) are focused onto a single receiving area on a 50-story tower which is filled with water. The heat generated by the focused beam flash-vaporizes the water, and that steam turns the turbines to generate electricity. Disturbingly, it also seems to incinerate things that fly in front of the tower. We were hoping the puffs were insects and not small birds, but couldn’t really tell. Eeek. Luckily, a newer and more efficient design has large mirrored troughs or half-pipes with a tube of water inside the half-pipe. The whole structure isn’t much over 30 feet tall, and since the heat stays inside the pipe it should be much less risky to birds. This type of solar power generation is much more efficient than the first solar arrays and this facility generates enough power to supply all of Seville. That’s a lot of watts.
Next stop: Italica, a large Roman settlement which is currently being excavated about 9 KM Northwest of Seville. Once a thriving metropolis, the emperors Trajan and Hadrian were from Italica. Many streets and building foundations have been excavated, with their mosaic floors in various stages of completeness. Very nice to look at, and we were all thankful not to have been the poor slobs laying those thousands and thousands of tiny pieces of tile. Some walls still had plaster and paint on them, and you could see the remains of under-floor heating and interior plumbing. No wonder they conquered half the world! The amphitheater is very impressive even in this ruined state.