The Contra Rotor Wind Turbine (CRWT) is an interesting concept promoted by a company called Wind Turbine Systems Pvt. Ltd, in India. In a CRWT, instead of one turbine with three blades mounted on a supporting tower, two turbines with six blades are mounted on a single tower. One turbine rotates in the clockwise direction and the other rotates in the anti-clockwise direction. Play the above embedded video to see a Contra Rotor Wind Turbine in action.
While the CRWT gives almost 40% more power than a normal wind turbine, the cost of the second turbine and generator (if applicable) are additional. But, to get the same power output from a normal wind turbine, its blade size and generator size needs to be increased, which also results in additional cost and transportation/installation challenges.
So, instead of increasing the size of wind turbines to increase their efficiency, can we look at having two turbines - one behind the other, sharing the same supporting tower, as in CRWT? If enough space is available or if larger turbines can be installed, can we just install two separate turbines instead?
Since I don't have the cost/efficiency figures, I am not able to answer that question. But, the absence of an entire tower will result in cost savings & mounting two turbines on a single tower will result in space savings. If you think that two turbines will result in additional strain on the tower - no, that will not happen. According to this analysis, the bending stress on the tower actually reduces because the torque produced by the two rotors counterbalance each other!
This is such a simple idea, but none of the large wind turbine manufacturers seem to have tried it. I appreciate Wind Turbine Systems Pvt. Ltd, for having pioneered this interesting concept and thinking unconventionally. These out-of-the-box ideas are much required in the alternate energy industry. Anyone else up to the challenge?
This is such a simple idea, but none of the large wind turbine manufacturers seem to have tried it. I appreciate Wind Turbine Systems Pvt. Ltd, for having pioneered this interesting concept and thinking unconventionally. These out-of-the-box ideas are much required in the alternate energy industry. Anyone else up to the challenge?
