Decommissioning of world’s first offshore wind farm offers an opportunity to see how industry costs have changed over the past 25 years.
Guest essay by T. A. “Ike” Kiefer
Lifetime Performance of World’s First Offshore Wind Farm
The first offshore windfarm in the world has just been decommissioned and is now being torn down ( http://ift.tt/2mVgHNn ). Its lifetime performance specs are illuminating in comparison with recent wind industry data, and alternative generation options.
Decommissioning has started at the 26-year old Vindeby offshore project, one of the world’s first. The 4.95MW Vindeby offshore project was installed in 1991 using 11 Bonus 450kW turbines. It operated 1.5-3.0km off the southern Danish coast.
1991 Vindeby Offshore Wind Farm – Denmark
Years of Operation: 1991-2016 (25)
Capital Cost: 75M Kroner = $13M (1991USD) = $23M (2017USD)
Number of Turbines: 11 @ 450 kW
Lifetime Generation: 243 GWh
Nameplate Capacity: 4.9 MW
Average Power Output: 1.1 MW
Cost/Nampepate Capacity: $2.65/Watt (1991USD), $4.7/Watt (2017USD)
Lifetime Capacity Factor: 22%
Cost/Effective Output: $12/Watt (1991USD), $21/Watt (2017USD)
Levelized Capital Cost: $53/MWh (1991USD), $95/MWh (2017USD)
Levelized VOM Cost: $65/MWh (Estimated using $130/kw-hr industry figures for 2015)
Lower Bound of LCOE: $160/MWh (2017USD)
2015 Industry Performance Data for Offshore Wind (http://ift.tt/1Pp2qji ).
Cost/Nameplate Capacity: $5/Watt
Capacity Factor: 40%
Cost/Effective Output: $12.5/Watt
O&M Costs: $130/kW-yr
Lower bound of LCOE: $150/MWh (2015USD), $154/MWh (2017USD)
Conclusions:
1. While turbines are getting larger, able to operate at lower wind speeds, and improving their capacity factors, the total lifecycle cost per unit of energy provided from offshore wind has not perceptibly decreased from 1991 to 2015. Higher costs of O&M for larger turbines farther offshore seems to consume savings from higher capacity factors.
2. As it is uncontrollably variable and weather dependent, offshore wind generation remains uncompetitive with gas and coal which are half the cost (~ $70/MWh LCOE) while providing fully dispatchable and weather-independent power that is of much higher value to a power grid.
