In search of alternate sources of power to the fossil fuels, solar energy got the biggest boost during the last 3 decades and to day this segment of energy business is growing at a frenetic pace because of heavy government subsidies and dramatic reduction in prices of solar panels. As sustainability is a major credential for alternate energy sources, there are other options like wind energy which has become predominant in some countries where strong winds are blowing during most times of the year, day and night. A serious limitation of solar energy is that sun shine on any day will depend on the weather and that too available only during day time. However high initial investment and logistics of maintenance pose some practical problems. Wind mills are also not considered environment friendly as the huge blades rotating due to wind impact invariably kill or maim birds. Recent innovations are encouraging in that blades are avoided in the design thereby making it an environment friendly technology. Here is a take on this new development which appears to be exciting.
Still, we'd be silly to assume that the current three-blade spinning turbine design is the pinnacle of achievement when it comes to wind energy. And the aforementioned commenter is right to suggest that researchers and entrepreneurs across the world are working on bladeless and otherwise bird-safe turbine designs. It's a pretty big stretch to suggest that these turbines are currently ready for prime time, making conventional turbines unnecessary, but advocates suggest these alternatives may offer significant improvements over their current, spinning wheel counterparts. Spanish company Vortex Bladeless is one of the companies that has been making headlines with its bladeless, gearless, bearingless vertical wind turbinethat its founders claim will, in addition to protecting birds and bats, significantly reduce the manufacturing and maintenance costs associated with conventional wind power (by 53 percent and 51 percent respectively). According to the MIT Technology Review, the company has already raised over $1 million in investor capital, and it also recently undertook a successful crowdfunding campaign to create a commercial pilot for its first product: A small scale bladeless turbine designed for use in developing countries. The company has generated a lot of interest in its concepts, thanks in part to coverage in publications like Wired. The buzz is due to the fact that Vortex Bladeless is designed to harness wind energy in an entirely different way to traditional turbines. Instead of using blades to capture the wind's energy through a spinning motion, the Vortex uses what's known as vorticity, an aerodynamic effect that happens when a fluid meets a solid structure —producing a pattern of spinning vortices. (The famed collapse of the Tacoma Narrows Bridge was an example of vorticity, and was actually the inspiration behind The Vortex.) In prototype form, the turbine consists of a fiberglass carbon fiber cone that vibrates when wind hits it. At the base are rings of repelling magnets that pull in the opposite direction to which the wind is pushing. Electricity is then produced via an alternator that harnesses the kinetic energy of the vibrations. Overall, its makers say the Vortex will produce less energy than a conventional turbine (about 30 percent less to be precise), but because you can fit twice as many in any given area, and because the costs are about half that of a traditional turbine, its hoped that the overall impact will be a net positive in terms of ROI, and that's before you take into account benefits like the lower cost of capital making it more accessible for individual installations, or the fact that bird and bat deaths would no longer need to be taken into account when siting such turbines.(Read further-http://www.technologyreview.com/news/537721/bladeless-wind-turbines-may-offer-more-form-than-function)
Whether the bladeless wind mills will answer all the issues that bedevil this sector is not certain but it has opened up future possibilities for spreading the concept of exploitation of wind energy with lesser investments and land requirement. One of the limitations cited by some critics is that capturing the wind and conversion into energy is significantly less by these contraptions compared to conventional turbines with blades. Probably this is more than offset by lesser investments and lesser land needs.