Evolution of Modern Wind Turbines Part B: 1988 to 2008 - Wind Turbine Technology: Fundamental Concepts of Wind Turbine Engineering - page 185

and cost competitive in terms of cost per kWh. This study also predicts that wind energy will
contribute 21 percent to 28 percent of the electricity demand in the European Union (EU),
and describes a long series of research and development improvements that will be necessary
to make wind cost competitive by 2030. The conclusions of the European study are similar
to those described previously for the United States.
No major technology breakthroughs are envisioned for wind turbine technology either
in the U.S. or European studies. Instead, many evolutionary steps executed over the next
two decades through incremental technology advances are seen to cumulatively bring about
a 30 to 40 percent improvement in the cost effectiveness of wind power, as has been achieved
over the past two decades.

Summary of Potential Future Turbine Technology Improvements

Several studies of advanced wind turbine concepts have been reported under the Wind-
PACT Project [1999] that identiied a number of areas where technology advances would
result in changes to the capital cost, annual energy production, reliability, and O&M. Many
of these potential improvements from a 2002 WindPACT study are summarized in Table
3-7. Also included in this table are estimates of the effects of the manufacturing learning-
curve , generated by several doublings of the turbine manufacturing output over the coming

Table 3-7. Areas of Potential Technology Improvement

Technical Area Potential Advances Increments from Baseline

(Best/Expected/Least)
Annual Energy
Production
(%)

Turbine Capital
Cost (%)

Advanced Tower
Concepts

* Taller towers in dificult locations
* New materials and/or processes
* Advanced structures/foundations
* Self-erecting, initial or for service

+11/+11/+11 +8/+12/+20

Advanced (En-
larged) Rotors

* Advanced materials
* Improved structural-aero design
* Active controls
* Passive controls
* Higher tip speed/lower acoustics

+35/+25/+10 -6/-3/+3

Reduced Energy
Losses and Im-
proved Availability

* Reduced blade soiling losses
* Damage tolerant sensors
* Robust control systems
* Prognostic maintenance

+7/+5/0 0/0/0

Drivetrain
(Gearboxes and
Generators and
Power Electronics)

* Fewer gear stages or direct drive
* Medium/low-speed generators
* Distributed gearbox topologies
* Permanent-magnet generators
* Medium-voltage equipment
* Advanced gear tooth proiles
* New circuit topologies
* New semiconductor devices
* New materials (GaAs, SiC)

+8/+4/0 -11/-6/+1

Manufacturing and
Learning Curve

* Sustained, incremental design and
process improvements
* Large-scale manufacturing
* Reduced design loads

0/0/0 -27/-13/-3

Totals +61/+45/+21 -36/-10/+21