Introduction to Modern Wind Turbines - Wind Turbine Technology: Fundamental Concepts of Wind Turbine Engineering - page 85

The recent development of cost models based on many wind turbines with three-bladed,
pitch-controlled, variable-speed rotors [Fingersh et al. 2006] permits estimates of component
cost contributions in more detail now than previously possible. For example, Table 2-4 is an
extended list of items to be considered when estimating the cost of a wind power station. In
this example, the station has a rated capacity of approximately 51 MW and is composed of
34 mature-design turbines rated at 1.5 MW each. Component costs have again been normal-
Table 2-4.
Recent Estimate of Relative Costs of Turbine and Site Components in a
51-MW Wind Power Station
Rotor Assemblies ............................................ . .............. 16.9 %
Blades............................................ 10.8 %
Hub.................................................3.1 %
Pitch Mechanism & Bearings ....................2.7 %
Spinner.............................................0.3 %
Nacelles and Power Trains ..................................................... . 46.4 % Turbine: 63.3 %
Gearbox.......................................... 10.8 %
Variable-Speed Electronics ......................8.4 %
Generator ..........................................7.0 %
Main Structure ....................................6.6 %
Electrical Connections............................4.3 %
Control, Safety, & Condition Monitoring.......2.5 %
Low-Speed Shaft..................................1.5 %
Nacelle Cover .....................................1.5 %
Yaw Drive and Bearing ..........................1.4 %
Hydraulic & Cooling Systems ...................1.3 %
Bearings ...........................................0.9 %
Mechanical Brakes, High-Speed Shaft, etc .....0.2 %
Towers ..................................................... . ....................... 10.5 %
Balance of Station ..................................................... . .......... 26.2 %
Electrical Interface & Connections ..............8.7 %
Roads, Civil Work, & Staging ...................5.6 %
Transportation.....................................3.6 %
Foundations .......................................3.3 %
Assembly & Installation..........................2.7 %
Permits, Engineering, & Site Assessment ......2.3 %
Initial Capital Cost of Wind Power Station ................................... 100.0 %
ized by the total installed capital cost. In this current estimate, the cost share of the rotor has
decreased while the nacelle and power train cost share has increased signiicantly, compared
with the 1988 estimate. This results in a net turbine share increase of about 12 percent, with
a comparable reduction in the balance of station share.
Fixed Charge Rate
The ixed charge rate in Equation (2-26) may be a composite of rates for different items
in Tables 2-3 and 2-4. It is sensitive to the cost of capital, method of capitalization, tax rates,
tax incentives, and the lifetime of the wind turbine system. Wind turbine economic stud-
ies have been made with ixed charge rates from 0.10 to 0.20. In their baseline cost model,
Fingersh et al. [2006] set the ixed charge rate at 0.116.