This is for my italian readers. This morning I’ve seen a post reblogged several times, it is about a “MagLev Wind Turbine”. In the post are reported some data, and it seems that this is a new, higly efficent, wind turbine. But there’s something that sounds strange to me, for example that the post refers that this new technology was presented at Wind Power Asia 2007. Why 2007? 4 year ago… Then, if you clic on the link, it’s broken. The site of the project consist, in practice, of a unique promotional video… mmh… I’ve searched on the internet, there are a plenty of site that write over and over the same thing on this wind turbine… mmh… Then I’ve hopped on the NewScientist’s blog, here’s what I’ve found:
Could gigantic maglev wind turbines be the answer to the world’s energy problems? It’s a cool idea, but somehow I doubt it.
Still, that’s what an Arizona-based company called Maglev Wind Turbine Technologies is proposing. It wants to build enormous vertical axis turbines that would use magnetic levitation to reduce friction.
On paper, the idea seems to have some merit. After all, a group of Chinese scientists did demonstrate a “maglev” wind turbine at the 2007 Wind Power Asia Exhibition in Beijing. Instead of ball-bearings it has magnetically levitated components. Scientists from Guangzhou Energy Research Institute and Guangzhou Zhongke Hengyuan Energy Science & Technology say it was up to 20% more efficient than a normal turbine and can also utilise wind speeds as low as 1.5 metres per second.
Vertical-axis wind turbines also have advantages. The main benefit is that the turbine does not have to face into the wind and that the generator and gearbox can be placed on the ground. A company called Vertaxwind is even working on designs for very large off-shore vertical-axis turbines.
So far, so good. But Gordon Edge at the British Wind Energy Association thinks giant maglev turbines could be pretty difficult to build.
"My understanding is that [maglev] only works for very small turbines," he told me. "It’s not something that’s being investigated for large machines. You’re talking about levitating a rotor of tens of tonnes which is going to require some very big magnetic fields."
I guess we shouldn’t write the idea off completely, but I’ll reserve judgement before declaring the world’s energy problems solved just yet.
So, I continue to have my doubts. In these days there’s a great debate on nuclear energy, but maybe we should look for really attainable technologies.
[…] During a supernova, stellar temperatures can briefly rise far above 6 billion kelvin. In 1987, a star was seen exploding in the Large Magellanic Cloud, a satellite galaxy of our own Milky Way some 160,000 light years away from us. Neutrinos from its heart detected on Earth revealed an internal temperature of about 200 billion kelvin. That’s nothing, though, compared with whatever produces a gamma-ray burst. These brief flashes of ultra-high-energy light are spotted once or twice a day by specially tuned telescopes. CRBs are thought to mark the birth of black holes, either when a giant star’s core collapses or when two ultra-dense neutron stars collide. Somehow the gravitational energy is turned into a tight beam of gamma rays and other radiation. While the details of this process are currently unknown, it must involve a fireball of relativistic particles heated to something in the region of a trillion kelvin (1012 K). Closer to home is a place that is even hotter: not a natural inferno, but a detector cavity 100 metres or so beneath the generally temperate outskirts of Geneva in Switzerland. There, between 8 November and 6 December 2010, nuclei of lead atoms were smashed together for the first time at CERN’s Large Hadron Collider in an attempt to mimic some of the universe’s opening moments. The result was the highest temperatures ever recorded on Earth, a subatomic fireball registering several trillion kelvin. […]
[The article is free but registration is required.]