The influence of power density on the value chain
The power density of a wind turbine is defined as its rated power divided by its swept rotor area. Both are key design parameters that are to be chosen by the wind turbine designer. The underlying design considerations may typically include considerations on energy yield, wind climate, structural loads and component costs. It is recognized that power density also has an influence further down the value chain of wind energy. In order to investigate some of these effects, a case study has been made for an offshore case.
This work was part of the project ‘Dynamic Power Management’, supported by TenneT TSO, and by the Dutch research program ‘Far and Large Offshore Wind’ and was presented at the Wind Integration workshop 2015 held in Brussels, Belgium.
Conclusions
- The trend towards a lower power density, as seen in the onshore market, is not seen in the offshore market for wind turbines in recent years.
- A lower power density leads to a higher capacity factor, which translates directly to the utilization rate of the electrical infrastructure.
- The optimum combination of rotor diameter and rated power is influenced by the costs of the electrical infrastructure that are taken into account. More costs of electrical infrastructure leads to the preference of larger rotor diameters and lower power densities.
- Lower power density leads to reduced sensitivity for year-to-year wind speed variation, which leads to reduced risk for the investor, and reduced uncertainty in the energy markets.
The full paper from this workshop can be downloaded here: Paper_WIW-049_Jaap_de_Boer.pdf