In 2005, wind turbines already supplied 5 per cent of gross electric power consumption. Although the installed power capacity was around 7 000 MW in 2000, it was already around 18 500 MW by the end of 2005. With the rapid technological development, German manufacturers and suppliers have become market leaders on the world market. According to calculations of the German Wind Energy Institute, more than 50 per cent of all wind turbines worldwide and their components are
1 2
3 4
Radiation
Transmitter SheathingOptical fibre substrate
Receiver
Connections 3,4
Connections 1,2
Input current IF Output current IC
Figure 7.84 Schematic of an optocoupler
Internal lightning protection system 423
produced in Germany. The export of wind power technologyamountsto60 percent of the overall turnoverof around five billion Euros of German manufacturers and safeguards therefore the most part of the 64 000 or so jobs in this industry.