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Kite Power: The Latest In Green Technology (thebulletin.org)
New submitter Dan Drollette writes: The solution to producing energy without contributing to global warming may be to go fly a kite. Literally. Researchers in Switzerland and Italy — high-altitude places where the winds are strong, steady and predictable — have been working on ways to generate electricity from kites that fly hundreds or thousands of meters high. The scientists already have a prototype cranking out 27 megawatts; they expect to have a 100-megawatt plant big enough to power 86,000 households. And they say that they can produce electricity for less that 4 cents per kilowatt-hour, which is better than fossil fuel. Plus, the kites look really cool (as does the "Darrieus rotor vertical axis wind turbine" at the base of the St Bernard Pass, on the Swiss side, which I've seen in operation in person).
I think they forgot to google for the technology first: https://www.google.com/makani/
What happens if the wind stops?
The utility plant operators have to compensate by running backwards and pulling harder on the string.
This has been around a while; kites, windbelts, and laddermills were my area to cover for presentations when taking classes on sustainable energy in 2010, and they were a lot of fun. Anything that gives you an excuse to play footage of the Tacoma Narrows Bridge collapsing and demonstrating the awesome power of wind is pretty cool.
Kites hold a lot of promise; they're far safer for wildlife than any turbine, even the large slow ones that don't deserve their bad rap, and they produce up to a third of a turbine's power given similar operating area, for a tiny sliver of the material cost. Solar's cool and all, but wind power has become surprisingly diverse in its options tailored for different environments, and is becoming more so.
Most other countries have continously falling birth rates, even the so called poor ones. The average birth rate in the African countries for instance is close to 2.5 children per woman, not much higher than for instance the U.S..
Thus back to airbombing people with the condom: It won't affect the birth rate. Birth rates decline in all countries with rising female education levels and better health care, wether you carpet bomb them with condoms or not.
Not much? Seriously?
In the 2006-2010 five year plan the real improvements in China's energy usage came from two programs.
Firstly, in the Thousand Enterprises Program the government forced China's top 1000 companies to completely rethink their energy use. They were told to monitor energy efficiency, and redesign, upgrade, and / or replace industrial equipment and software with the aim of becoming more energy efficient, reducing the amount of power they used without denting their productivity. The other program was even more drastic. Thousands of small, inefficient, factory units and assembly lines across the country were simply closed down.
The above programs were so successful (a roughly 19% cut in their energy intensity) that they were extended and expanded for the current five year plan: smaller, inefficient units are continuing to close down, and the Thousand Enterprises Program has become the Ten Thousand Enterprise Program. Current indications suggest that China has met its target of a further 16% cut in their energy intensity.
In addition, China has more installed wind power than any other country in the world, and has the second largest installed solar power capacity. I've also read that they (the Chinese government) are actively looking at new nuclear power plant designs as well as thorium salt reactor designs, which is a direct contrast to pretty much every single western government.
If all this qualifies as "not much" I'm not sure what it would take to impress...
1) I've stood directly underneath a 1MW turbine in the middle of a large wind farm on a windy day. There wasn't much noise at all, just a light whoosh... whoosh... whoosh.... I don't know where this concept that wind turbines are "terribly noisy" comes from, but it doesn't at all match my experience.
2) You're concerned with noise about something that's hundreds of meters up? What about kite-based systems that operate at thousands of meters up, would you be worried about noise from them too?
He's the sort of person who would sell the Red Cross to Dracula.
The global wind resource is 72TW. You're going to have a hard time denting that. You might alter things locally - might - but not globally.
And besides that... if any evil greedy megacorp wants to move into my valley and setup something that will rob the wind of its energy... Please Do! Seriously, someone should really work on wind turbines specifically designed to act as windbreaks, in a manner that can be affordably mass produced and deployed in lieu of traditional manufactured windbreak systems.
(Before anyone says "just plant some trees..." I do, every year. They usually get killed by the weather, sometimes outright uprooted. I may have to start spending more time on each tree individually, encasing each one in its own individual PVC windbreak in addition to the broad rows of pallet windbreaks)
He's the sort of person who would sell the Red Cross to Dracula.
Even if China isn't exploring new fancy nuclear designs, they currently have 26GW of generation capacity, they are bringing a further 40GW online in the immediate future (plants already under construction many of which are nearly finished), and a further 50GW of generation capacity is already planned beyond that. That's a bigger push for CO2 free energy than a lot of other countries are currently making.
If I remember this company's tech correctly, the wind drags it out, turning a generator as it goes. They then switch it to a low-drag mode and reel it back in. So it cycles between high power generation and low power consumption. The concept being that you'd have many of them so that you'd get continuous net generation.
Slow and powerful drag out is going to have a massive, complicated, and hard to maintain gear box to run a generator. Generators run at hundreds of RPM. This is the same problem with big wind turbines, making power into RPM in a gear box is hard. If you have a wind farm around, look at the ones that are stopped they'll have black stains on them where the gear box failed.
On a tower, they are difficult to service.
On a floating, bobbing, need to use a boat to get to, they are probably going to have to un-hook them and bring them to shore to fix.
Those kite things are overly optimistic given the state of the gearbox technology used today.