NREL’s Windturbine design cost & scaling model (I): Introduction
The document is free: http://www.nrel.gov/wind/pdfs/40566.pdf
SOURCES OF INFORMATION
The study is made using three different information sources:
1. The studies made by the University of Sutherland ordered by the Department of Trade & Industry of the UK.
2. The WindPACT studies (Wind Partnership for Advanced Component Technology) and LWST (Low Wind Speed Technology) ordered by the Department of Energy of the USA and developed by the NREL.
3. The studies made by private companies as LM Glasfiber or TPI Composites.
The main objective of this report is double. First, the report estimates reliably the masses and costs of the components of a windturbine of a particular configuration. Second, the study hopes to measure the influence of economic indexes like the GDP or the PPI (Producer Price Index) in the cost of the windturbine.
The study differentiates between land-based and offshore turbines.
In order to develop the model, the NREL assumes that the windturbine has the following characteristics:
- Located in a 500 MW wind farm
- With 3 blades
- Pitch controlled
- Variable speed electronics
The inputs of the model are:
- The machine rating
- The rotor diameter
- The materials for the tower and blades. Types: basic or advanced
- The drive train configuration. Types: Planetary-helical three stages gearbox coupled with a high speed generator, One-stage gearbox coupled with a permanent magnet generator (medium speed), Multiple generators and Direct drive.
- The capacity factor
Additionally, to develop the formulae for the offshore configuration, the report assumes the marine wind farm to produce 500 MW using 167 windturbines. The turbines are supposed to have 90 meters of diameter, 80 meters of hub height and to be installed 5 miles far from the coast and above a 10 meters deep sea bottom. The distance between turbines must be of 7 rotor diameters and they must be manufactured using basic materials (not advanced).