Wind turbines operate on a simple: the stronger the wind blows, the more power you get, so when the air is too still can complicate things. To combat this little problem, Apple has registered a patent for a system that stores excess energy when the wind is strong and uses it when it is weak.
There are similar models that store extra energy in batteries, but the idea of the apple is something different. Apple system makes use of rotating turbines to generate heat in a liquid by means of friction, then handles a heat exchanger transferring heat to a second liquid until it produces steam drives a steam turbine. When winds are strong the first liquid is heated more than necessary to evaporate the latter. Then, when the winds are calm, the stored heat can be used to generate steam without having to resort to direct action of the turbine.
Why Apple is working on a system of this kind is something we do not know as it moves away from its usual products, but since the company uses alternative energy in their data centers is likely to be signed up to use that infrastructure. We currently do not expect to see any MacBook with a small wind turbine mounted on top.
