This Stanford study is very exciting... as in.. exciting enough that it engendered for me an incredible Technicolor, vivid-dream, so real that it was a real drag (drogue) to awaken this morning.
Firstly, the study indicates that the many of the best sites, by far (considering all the factors), are in the ocean just offshore, especially off the Pacific west coast of the USA, which it seems has more reliable winds than the North Sea.
I had a vision (dream) of a beautiful "sailing ship" implementation for wind energy... I believe these ships can be aesthetically pleasing enough to be positioned all up and down the Pacific coastline, out about 10 km. but still barely visible because of their size. These sleek vessels could be more efficient and cost effective than fixed offshore windmills, will not need to be firmly anchored, which is basically impossible on the Pacific, due to the depth... and may observers might even imagine them to be beautiful, after getting accustomed to the novelty. They were certainly exquisite in my vision.
I would like to reduce this vision to a visual image eventually, but lacking that at the moment, here is the best verbalization I can muster.
Imagine a ocean-going catamaran large enough to handle rough seas. Lets say the aerodynamic twin hulls are each 200 meter-long slivers. They can be constructed of steel-clad ferrocement. Atop the hulls, and parallel to the ocean but 20 meters above the surface is a strong, open circular track, 150 meters in diameter. Riding on this track is your steerable, super-size-it, 70-story high wind-ladder.
From a distance, the rotating wind ladder looks like aFerris-wheel on a beam reach but with the wheel-edge, not the axis hub, pointing into the wind. It is extremely lightweight construction, so that the most visible thing one sees are the 12 wings which are positioned around the circumference. The wings mount between the two open-disks of the Ferris wheel, providing both lift and compression on one revolution. But the disks themselves are almost unseen from afar, as they are mostly Kevlar cable with some grided tubing going up to both-ends of the 12 wings, which span between the two open disks and two hulls, and are tiltable at the 90-degree joint with the wheel.
These ladder-wings individually are not unlike airplane wings, and each has 2 or more large spinning tractor propellers (mounted on trailing edge) driving generators, which in addition to the torque on the wheel itself, caused by the lift of the wings, supply the power. The wings are tiltable, just like the wind-ladder to present the proper angle of attack, and are constantly changing each revolution, for either normal lift on the upside, or tilting-down for compressive force on the downside. Robotic servo motors can take care of that constantly changing alignment-angle chore.
As mentioned, the ship itself does not need to be anchored at all, but can be held relatively stationary, in a controlled-drift mode, by large hybrid drogues... but here is the interesting thing. The sea-drogues themselves can have propellers in the vertex of each open cone to supply power as they are moving in a controlled drag/drift. They can do this for maybe 22 out of 24 hours of a day, with perhaps a 2 hour daily period (preferably low wind time) when the drogues are raised out of the water, and the ship then powers back to its original starting point. There is no "net movement" over time but perhaps a 40 mile (shuttle)movement per day.
Obviously with this arrangement, there is no undersea cable back to shore to carry electrical power... so what gives?
This is another grand feature (maybe) of the completed concept, as the energy product of these sailing factories is not electrical current at all, but instead is **liquid air** (enriched in O2). Whenever there is adequate wind, day or night, the generated power is used onboard to compress air and cool it in many stages till liquidified ... but when done in many stages using the ocean heat sink and with heat-pump efficiency, then we have a proven COP of about 4, just like the Linde method. The liquid air is stored in the hulls until a dedicated tender arrives to unload the "fuel" product and ferry it to shore. One tender could service perhaps a dozen production vessels spread over 100 miles of open sea, but not far offshore and lightly crewed.
Once ashore, the liquid air can be expanded through turbines in a dedicated power-plant, and especially done so during peak electrical demand periods, where the "value added" of the storable fuel is greatest. Since this diurnal demand cycle is also the hours between 10 AM and 6PM, when the sun is strong, the power plant can benefit from solar heat in the expansion equation, collected with mirrors, to boost the expansion efficiency of the liquid air... and/or, being enriched in O2, even a tiny amount of methane will push the expansion ratio way over the 100% "effective" Carnot level.
Consequently one has accomplished three desirable goals 1) Ecologically sound wind energy 2) Stored energy which can be used at peak demand 3) Aesthetics
...and possible the best of all, which is not easy to ascertain now, but looking good, and that is ROI...
Which is return-on-investment, Roy.
Jones
Le Roi d'lover n'est pas Mort, Vive Le Roi!
