热度 17
2014-1-23 19:12
1749 次阅读|
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I'm always keen on follow ups to "next big thing" predictions that have come true, as well as the many that haven't. While some of these predictions are based mostly on wishful thinking and marketing hype (remember widespread 3D TV at home?), many are based on genuine, substantial technical advances—yet fall short for practical or implementation reasons. It's nothing to be embarrassed about, as many technical advances fall short in reality, while others go far beyond what was envisioned. (When the laser was first demonstrated, one writer said "it is a solution in search of a problem"—well, we all know how the laser turned out!) Media and press updates don't help much, as editors are under constant pressure to cover new things and not look back; thus, they tend to not do any sort of follow-up to what they were writing about last year. Which brings me to my question: What's the true status of superconducting power lines? A few years back, we heard that such lines, based on recent advances in high-temperature superconductivity (HTSC) and materials, would be used for some installations of power-grid infrastructure. We'd reached a tipping point, where the benefits of their near-zero IR loss outweighed the upfront cost of the special power lines and support equipment. There are even a few pilot commercial installations (see here and here ). Construction details of a medium-voltage superconducting cable (provided by Nexans S.A.). But beyond that, it doesn't seem that much is happening—or is it that the progress is not getting the attention it should? Is the harsh reality that the costs and real-world complexities of installing, running, and maintaining these lines and systems overwhelms the benefits? Or maybe there are genuine successes, but we're not hearing about them because the audience is more interested in the latest smartphones and trendy apps to help you find a better ethnic restaurant that is nearly equidistant from you and three friends (I'm not making that up!)? Certainly, superconductivity is now in widespread commercial use, primarily in MRI (magnetic resonance imaging) systems, where the magnetic fields need to be extremely powerful (several Tesla is now common), and losses in the coils are costly and severely diminish performance. But MRIs are fixed, highly localized installations, and so have fewer real-world issues than a broadly dispersed power line. Also, if there is a problem with the superconducting sub-system (yes, leaks and other issues do happen), the impact, while unpleasant, only affects the immediate patients and medical team, not the delivery of substantial grid power to a large area and its many users. Some publications and journalists used to do a regular "whatever happened to?" segment every year, where they looked at recent projections of what would be the next big thing(s), and assessed where those things actually stood. You don't see much of that look-back reporting anymore: It takes a lot of time, energy, and work to research, and I wonder if the broad audience really cares (although I am very interested). So, what's the reality on superconducting power lines? Are they a great idea whose time has come, will come soon, or maybe it has already passed? (One leading source of these lines and systems, American Superconductor Corporation, has seen modest revenue growth but also substantial on-going losses.) Is the increased use of wind/solar power farms a big opportunity for these lines, or not? Going beyond superconducting power lines, are there any other much-hyped "next big things" on which you'd like to see updates? My list is pretty long!