Abstract:
It is well established that the energy driving the winds on Earth is about 2.5 W/m2 in a global average. Wind farms are typically producing between 0.5 and 5 W/m2, depending on their location, size and installed capacity. This is of the same order of magnitude as the 2.5 W/m2 driving the winds, and suggest the possibility that the power production may be limited by the atmospheric input of energy.
Power generation per unit area is typically reduced with increasing area of wind farms. This is because, in large wind farms, winds are damped before they reach the interior of the farm. Power generation thus partially depends on the atmospheric conversion from potential to kinetic energy over the actual wind farm. Theoretical analysis of the atmospheric energy input to wind farms compares well with the observed power generation of wind farms in the North Sea. The results show that the power generation and the energy input both decrease similarly with area, suggesting that the atmospheric energy input is the main limiting factor.
For large (> 500 km2) wind farms the energy input is mainly given by the conversion from potential to kinetic energy, which is between 2-4 W/m2 in the North Sea, according to meteorological reanalysis data. Since wind farms also generate extra turbulence, only about 1/4 of this is possible to convert to electric power. This agrees well with the observed power generation, which indicates that large wind farms will produce 1 W/m2 or less. Thus, for offshore wind to play a major role in the energy transition in Europe, an area comparable to the entire North Sea is needed. Unfortunately, the limits to power production set by the atmospheric energy input is not always taken into account when estimating the power potential for offshore wind.
What is the Joint Oslo Seminar (JOS):
- Atmospheric and climate sciences have a stronghold in Oslo among the four institutions University of Oslo, the Meteorological Institute, CICERO and NILU.
- This joint seminar invites renowned international experts to contribute to an informal series of lectures, meant to create interaction with the Oslo atmospheric and climate science community on recent highlights and analysis in the field.
- All seminars will be held on Thursdays (12:15 pm -1 pm).