The Wind is Free!

How on earth do you/the electric board get it in phase with the national grid? Won't you lose a lot of energy converting it to the correct 50/60 Herts? I'm guessing transformers are involved somewhere...or maybe not!

Its basically an inverter, which yes, does lose some energy. And yes they generally use transformers to inclrease the voltage.

Some inverters (more expensive) can monitor the mains current, and invert the DC supply into a since wave which matches the phase of the mains.

Cheap inverters just invert to a square wave, or to a combination of square waves.

The system has a sine wave inverter built in which is in sync with the 50 Hz alternating mains. it then increases the voltage slightly in the system causing current to flow back into the mains as a load. Monitoring this very carefully and not allowing a phase shift to take place.
At the moment the systems in Europe some are as high as 97 percent efficient!