OFFERING MEMORANDUM Global Offering of up to ... - Nordex

Glossary
Alternative energy sources Those sources of energy which renew themselves constantly and
are practically inexhaustible: solar energy, biomass, d wind
energy, ambient heat, etc. Contrast with d conventional energy
sources.
Asynchronous generator The rotation speed of the rotor of an asynchronous generator is
different to the d grid frequency (50 Hz in Europe Hertz). Due to
its construction it is very robust and does not require much
maintenance. The double-fed asynchronous generator has several
technical advantages. Due to the additional costs the decision to
use a double-fed asynchronous generator is a balancing of
economic and technical considerations. Double-fed asynchrouous
generators have been used for several years in conventional power
plants which means that it is possible to rely on operational knowhow.
Average annual wind speed The average wind speed over a year, measured in d m/s.
Blade pitch adjustment Turning the rotor blades of a d pitch-regulated turbine around
their longitudinal axis. In the case of a pitch-regulated wind
turbine, the turbine’s electronic controls constantly measures the
power output. When the power output is too high, the controller
sends a command to the blade pitch mechanism which
immediately pitches (turns) the rotor blades slightly out of the
wind. Conversely, the blades are turned back into the wind
whenever the wind drops again. The rotor blades thus have to be
able to turn around their longitudinal axis (to pitch). During normal
operation, the blades pitch a fraction of a degree at a time while
the rotor is continuing to turn.
Designing a pitch-regulated wind turbine requires sophisticated
engineering to make sure that the rotor blades pitch exactly the
amount required. On a pitch-regulated wind turbine, the
electronics control will pitch the blades every time the wind
speed changes, which ensures that the rotor blades are always at
the optimum angle in order to maximise output across all wind
conditions.
Certification Wind turbines are certified pursuant to certain regulations. This
ensures the correct planning and safety of operation of the wind
turbines. Germanische Lloyd (GL), based in Hamburg, is the
authoritative body for wind turbine certification in Germany.
Constant-speed wind turbine Turbine which can operate at only one or ^ in worst cases two fixed
rotation speeds. While technically far simpler, these turbines do not
permit optimal use of d wind energy (see d variable-speed wind
turbine).
Conventional energy sources All d fossil fuels as well as nuclear power and hydroelectric power.
Cut-out speed The wind speed at which the d wind turbine is shut down for
safety reasons (as a rule around 25 meters per second d m/s).
G-1