GE's Risky Energy Research

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TR: Do you think it will be possible someday to apply this to aviation? Jet engines?

MI: Someday.

TR: What are the challenges?

MI: Weight. It will take a while. To stay in this business long-term, we have to take big bets. And that's a big bet.

TR: This will make existing power plants more efficient, and so reduce carbon emissions. What about renewable energy?

MI: We're going offshore, making large offshore wind turbines. Today offshore wind is much more expensive [than onshore wind] because the platform for the turbine is so expensive--basically you have to build an oil platform. [To bring down costs] you have to put together technologies that allow you to extract the most from wind.

TR: I've been told by some experts that wind turbines can't be made much more efficient than they are now. Can you make them much more efficient?

MI: Yes, you can. If you look at a wind turbine, there are a couple of things. One is the blade. The blade has to get larger. It has to be much more aerodynamic. It has to be able to take twist-bend coupling. It has to look more like a wing, although it's actually more complex than a wing, because your velocities vary from the hub to the tip. We believe there are a lot of opportunities in the next-generation wind blade. We are developing low-cost composites to be able to build a spar--the core of the blade--that handles the loads. And then we believe that the next generation of wind blades will have active flow control, to be able to shape the airfoil for the conditions, to get maximum power out of it.

TR: As in shapeshifting materials?

MI: There are many ways to get active flow control. One way is just to blow air from the leading and the trailing edge. We just need to find a way that will get us there at the lowest cost and the highest reliability, that can withstand lightning strikes and all the environmental considerations.

TR: So that's the blades. What else could you do?

MI: The generator. Today you go through the gearbox, to the generator, into the inverter to get to the right voltage, the right frequency. We believe in going to direct drive [without a gearbox]. That can lead to very big generators, 8 meters in diameter. We are working on changing the paradigm, making these generators smaller, to be able to handle low speed with a high efficiency. We are also developing better power electronics to produce higher voltage for transmitting the power to shore. We are working with a number of technologies to make the wind turbine out in the sea economical.