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coastline, etc.), has been used to restrain the Five models of wind turbines have been used to
area allowable for the offshore wind turbines calculate the annual energy production at a
placement, as shown in Figure 4. place into the selected allowable sea area (Table
3). Two of them are of the present commercial
To identify a possible installation site a generation (Bonus and DeWind) and two
miminum distance of 3 km from the coastlines models are specific offshore turbines (Tacke and
and a maximum depth of 20-25 m below the Vestas): their power curves have been provided
sea level have been used. by the respective manufacturers on a
confidential basis. The fifth model is the
The estimated wind parameters for the site, at prototype of the Gamma 60 turbine, and has
an height of 80 m asl, are the following: been included to get a view of the technological
advances in the last years.
Weibull C: 7.6 m/s
Weibull k: 1.75
Annual Mean Wind Speed: 6.8 m/s
Rated Rotor
The analysis has been completed with the WTG Power diameter
calculation of the estimated annual energy [kW] [m]
output produced by a commercial wind turbine Bonus 1MW 1000 54.2
which could be potentially installed in the DeWind 60 1300 60.0
selected area. Tacke TW 2.0 2000 70.5
Vestas V80 2000 80.0
Several wind turbine manufactures have already Gamma 60 1500 60.0
or are very close to launch on the market their Table 3: Models of WTG used in simulation
machine models specifically designed for
offshore application. These turbines are large
sized (up to 2.0 MW of rated power), and have The same tower height of 80 m asl for all the
been developed with the aim of reducing to a models has been assumed to calculate the
minimum the impact of the expected high costs specific annual energy production, in kWh per
2
of installation and maintenance, due to the m of rotor swept area. On average for the four
particularly aggressive conditions characterising "modern" models the expected specific energy is
2
the environment of the offshore plants. equal to 1105 kWh/m /year, with single values
rather close each other. As expected, the value

4215000

4210000
Meteo Station

North Latitude [m] 4205000 10.0
7.2
7.1
7.0
6.9
6.8
6.7
6.6
4200000 Potential Allowable 6.5
Offshore Plant Area
6.4
6.3
6.2
Figure 4:Synopsis Wind Speed [m/s] 6.1
h=80m agl 6.0
4195000
0.0
260000 265000 270000 275000 280000 285000 290000
East Longitude [m]