Page 174 - Fluid Power Engineering

CHAPTER8

Advanced Wind

Resource

Assessment

As far as the laws of Mathematics refer to reality, they are not certain,
and as far as they are certain, they do not refer to reality.
—Albert Einstein

Introduction
This chapter will cover advanced topics in resource assessment. The
first topic is extreme wind speed (EWS). EWS is an estimate of the
wind speed that is exceeded once every 50 years. As a part of resource
assessment, EWS is used to determine the Class of wind turbine and
used by the turbine manufacturer to determine if the turbine has the
capability to withstand loads associated with EWS. The second topic
is RIX, an enhancement to the WAsP model for rugged terrain. The
third topic is wake of turbines and the associated losses in energy
production. Alternate methods for modeling wake are presented. The
next section presents the definition of International Electrotechnical
Commission (IEC) Classes of wind turbines.
Investors in a wind project are keen to understand if all the losses
have been accounted for and the uncertainty of a project has been
modeled in a resource assessment. The final sections deal with losses,
uncertainty, and the role of uncertainty in a bankable wind resource
assessment.

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