
170 Principles of Sustainable Energy Systems
© 2008 Taylor & Francis Group, LLC
C
p
= C
pmax
at all wind conditions. The CSVP runs at a variable C
p
. Since the turbine cannot
vary rotor speed, it cannot run at C
p
= C
pmax
at all conditions.
Note that both turbines eventually reach a rated power of 5 MW. However, the CSVP
reaches the 5 MW turbine rating at a higher wind speed, 15 m/s, while the VSVP turbine
reaches 5 MW rated power at 13.5 m/s. This is because the CSVP turbine is operating at a
lower C
p
and thus needs a higher wind speed to reach the higher 5 MW power rating. For
the purposes of this illustration, C
p
for the CSVP was assumed to be a ...